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Sample records for annual ryegrass lolium

  1. Allelopathic interference of alfalfa (Medicago sativa L.) genotypes to annual ryegrass (Lolium rigidum).

    Science.gov (United States)

    Zubair, Hasan Muhammad; Pratley, James E; Sandral, G A; Humphries, A

    2017-07-01

    Alfalfa (Medicago sativa L.) genotypes at varying densities were investigated for allelopathic impact using annual ryegrass (Lolium rigidum) as the target species in a laboratory bioassay. Three densities (15, 30, and 50 seedlings/beaker) and 40 alfalfa genotypes were evaluated by the equal compartment agar method (ECAM). Alfalfa genotypes displayed a range of allelopathic interference in ryegrass seedlings, reducing root length from 5 to 65%. The growth of ryegrass decreased in response to increasing density of alfalfa seedlings. At the lowest density, Q75 and Titan9 were the least allelopathic genotypes. An overall inhibition index was calculated to rank each alfalfa genotype. Reduction in seed germination of annual ryegrass occurred in the presence of several alfalfa genotypes including Force 10, Haymaster7 and SARDI Five. A comprehensive metabolomic analysis using Quadruple Time of Flight (Q-TOF), was conducted to compare six alfalfa genotypes. Variation in chemical compounds was found between alfalfa root extracts and exudates and also between genotypes. Further individual compound assessments and quantitative study at greater chemical concentrations are needed to clarify the allelopathic activity. Considerable genetic variation exists among alfalfa genotypes for allelopathic activity creating the opportunity for its use in weed suppression through selection.

  2. Cross-resistance to herbicides in annual ryegrass (lolium rigidum)

    International Nuclear Information System (INIS)

    Christopher, J.T.; Powles, S.B.; Liljegren, D.R.; Holtum, J.A.M.

    1991-01-01

    Lolium rigidum Gaud. biotype SLR31 is resistant to the herbicide diclofop-methyl and cross-resistant to several sulfonylurea herbicides. Wheat and the cross-resistant ryegrass exhibit similar patterns of resistance to sulfonylurea herbicides, suggesting that the mechanism of resistance may be similar. Cross-resistant ryegrass is also resistant to the wheat-selective imidazolinone herbicide imazamethabenz. The cross-resistant biotype SLR31 metabolized [phenyl-U- 14 C]chlorsulfuron at a faster rate than a biotype which is susceptible to both diclofop-methyl and chlorsulfuron. A third biotype which is resistant to diclofop-methyl but not to chlorsulfuron metabolized chlorsulfuron at the same rate as the susceptible biotype. The increased metabolism of chlorsulfuron observed in the cross-resistant biotype is, therefore, correlated with the patterns of resistance observed in these L. rigidum biotypes. During high performance liquid chromatography analysis the major metabolite of chlorsulfuron in both susceptible and cross-resistant ryegrass coeluted with the major metabolite produced in wheat. The major product is clearly different from the major product in the tolerant dicot species, flax (Linium usitatissimum). The elution pattern of metabolites of chlorsulfuron was the same for both the susceptible and cross-resistant ryegrass but the cross-resistant ryegrass metabolized chlorsulfuron more rapidly. The investigation of the dose response to sulfonylurea herbicides at the whole plant level and the study of the metabolism of chlorsulfuron provide two independent sets of data which both suggest that the resistance to chlorsulfuron in cross-resistant ryegrass biotype SLR31 involves a wheat-like detoxification system

  3. Phytoremediation of high phosphorus soil by annual ryegrass and common bermudagrass harvest

    Science.gov (United States)

    Removal of soil phosphorus (P) in crop harvest is a remediation option for soils high in P. This four-year field-plot study determined P uptake by annual ryegrass (ARG, Lolium multiflorum Lam.) and common bermudagrass (CB, Cynodon dactylon (L.) Pers.) from Ruston soil (fine-loamy, siliceous, thermic...

  4. Phosphorus status and microbial community of paddy soil with the growth of annual ryegrass (Lolium multiflorum Lam.) under different phosphorus fertilizer treatments*

    Science.gov (United States)

    Guo, Hai-chao; Wang, Guang-huo

    2009-01-01

    Annual ryegrass (Lolium multiflorum Lam.) was grown in paddy soil in pots under different phosphorus (P) fertilizer treatments to investigate changes of P fractions and microbial community of the soil. The treatments included Kunyang phosphate rock (KPR) applications at 50 mg P/kg (KPR50) and 250 mg P/kg (KPR250), mono-calcium phosphate (MCP) application at 50 mg P/kg (MCP50), and the control without P application. The results showed that KPR50, KPR250, and MCP50 applications significantly increased the dry weight of the ryegrass by 13%, 38%, and 55%, and increased P uptake by 19%, 135%, and 324%, respectively. Compared with MCP50, the relative effectiveness of KPR50 and KPR250 treatments in ryegrass production was about 23% and 68%, respectively. After one season of ryegrass growth, the KPR50, KPR250, and MCP50 applications increased soil-available P by 13.4%, 26.8%, and 55.2%, respectively. More than 80% of the applied KPR-P remained as HCl-P fraction in the soil. Phospholipid fatty acid (PLFA) analysis showed that the total and bacterial PLFAs were significantly higher in the soils with KPR250 and MCP50 treatments compared with KPR50 and control. The latter had no significant difference in the total or bacterial PLFAs. The KPR50, KPR250, and MCP50 treatments increased fungal PLFA by 69%, 103%, and 69%, respectively. Both the principal component analysis and the cluster analysis of the PLFA data suggest that P treatments altered the microbial community composition of the soils, and that P availability might be an important contributor to the changes in the microbial community structure during the ryegrass growth in the paddy soils. PMID:19817001

  5. Towards in vitro fertilization, gametosomatic cybridization and DNA transfer in perennial ryegrass (Lolium perenne L.)

    NARCIS (Netherlands)

    Maas, van der H.M.

    1994-01-01

    In this thesis, research towards invitro fertilization, gametosomatic cybridization andDNAtransfer in perennial ryegrass ( Loliumperenne L.), the most important forage

  6. Expressed sequence tag-derived microsatellite markers of perennial ryegrass (Lolium perenne L.)

    DEFF Research Database (Denmark)

    Studer, Bruno; Asp, Torben; Frei, Ursula

    2008-01-01

    An expressed sequence tag (EST) library of the key grassland species perennial ryegrass (Lolium perenne L.) has been exploited as a resource for microsatellite marker development. Out of 955 simple sequence repeat (SSR) containing ESTs, 744 were used for primer design. Primer amplification was te...

  7. Toxicity and uptake of cyclic nitramine explosives in ryegrass Lolium perenne

    International Nuclear Information System (INIS)

    Rocheleau, Sylvie; Lachance, Bernard; Kuperman, Roman G.; Hawari, Jalal; Thiboutot, Sonia; Ampleman, Guy; Sunahara, Geoffrey I.

    2008-01-01

    Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) are cyclic nitramines used as explosives. Their ecotoxicities have been characterized incompletely and little is known about their accumulation potential in soil organisms. We assessed the toxicity and uptake of these explosives in perennial ryegrass Lolium perenne L. exposed in a Sassafras sandy loam (SSL) or in a sandy soil (DRDC, CL-20 only) containing contrasting clay contents (11% and 0.3%, respectively). A 21-d exposure to RDX, HMX or CL-20 in either soil had no adverse effects on ryegrass growth. RDX and HMX were translocated to ryegrass shoots, with bioconcentration factors (BCF) of up to 15 and 11, respectively. In contrast, CL-20 was taken up by the roots (BCF up to 19) with no translocation to the shoots. These studies showed that RDX, HMX, and CL-20 can accumulate in plants and may potentially pose a risk of biomagnification across the food chain. - Cyclic nitramine explosives accumulate in perennial ryegrass and exhibit distinct uptake patterns

  8. Toxicity and uptake of cyclic nitramine explosives in ryegrass Lolium perenne

    Energy Technology Data Exchange (ETDEWEB)

    Rocheleau, Sylvie; Lachance, Bernard [Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, Quebec H4P 2R2 (Canada); Kuperman, Roman G. [Edgewood Chemical Biological Center, 5183 Blackhawk Road, Aberdeen Proving Ground, MD 21010-5424 (United States); Hawari, Jalal [Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, Quebec H4P 2R2 (Canada); Thiboutot, Sonia; Ampleman, Guy [Defense Research and Development Canada, 2459 Pie IX Boulevard, Val Belair, Quebec G3J 1X5 (Canada); Sunahara, Geoffrey I. [Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, Quebec H4P 2R2 (Canada)], E-mail: geoffrey.sunahara@cnrc-nrc.gc.ca

    2008-11-15

    Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) are cyclic nitramines used as explosives. Their ecotoxicities have been characterized incompletely and little is known about their accumulation potential in soil organisms. We assessed the toxicity and uptake of these explosives in perennial ryegrass Lolium perenne L. exposed in a Sassafras sandy loam (SSL) or in a sandy soil (DRDC, CL-20 only) containing contrasting clay contents (11% and 0.3%, respectively). A 21-d exposure to RDX, HMX or CL-20 in either soil had no adverse effects on ryegrass growth. RDX and HMX were translocated to ryegrass shoots, with bioconcentration factors (BCF) of up to 15 and 11, respectively. In contrast, CL-20 was taken up by the roots (BCF up to 19) with no translocation to the shoots. These studies showed that RDX, HMX, and CL-20 can accumulate in plants and may potentially pose a risk of biomagnification across the food chain. - Cyclic nitramine explosives accumulate in perennial ryegrass and exhibit distinct uptake patterns.

  9. Bale Location Effects on Nutritive Value and Fermentation Characteristics of Annual Ryegrass Bale Stored in In-line Wrapping Silage

    Directory of Open Access Journals (Sweden)

    K. J. Han

    2014-09-01

    Full Text Available In southeastern regions of the US, herbage systems are primarily based on grazing or hay feeding with low nutritive value warm-season perennial grasses. Nutritious herbage such as annual ryegrass (Lolium multiflorum Lam. may be more suitable for preserving as baleage for winter feeding even with more intensive production inputs. Emerging in-line wrapped baleage storage systems featuring rapid wrapping and low polyethylene film requirements need to be tested for consistency of storing nutritive value of a range of annual ryegrass herbage. A ryegrass storage trial was conducted with 24-h wilted ‘Marshall’ annual ryegrass harvested at booting, heading and anthesis stages using three replicated in-line wrapped tubes containing ten round bales per tube. After a six-month storage period, nutritive value changes and fermentation end products differed significantly by harvest stage but not by bale location. Although wilted annual ryegrass exhibited a restricted fermentation across harvest stages characterized by high pH and low fermentation end product concentrations, butyric acid concentrations were less than 1 g/kg dry matter, and lactic acid was the major organic acid in the bales. Mold coverage and bale aroma did not differ substantially with harvest stage or bale location. Booting and heading stage-harvested ryegrass baleage were superior in nutritive value to anthesis stage-harvested herbage. Based on the investigated nutritive value and fermentation characteristics, individual bale location within in-line tubes did not significantly affect preservation quality of ryegrass round bale silages.

  10. Allelopathic effect of ryegrass (lolium persicum) and wild mustard (sinapis arvensis) on barley

    International Nuclear Information System (INIS)

    Baziar, M.R.; Farahvash, F.; Mirshekari, B.; Rashidi, V.

    2014-01-01

    Most crop plants and weeds have allelopathic effects and analysis of these effects on plants in crop alteration and successive planting is very important. In this research the allelopathic ability of different parts and concentrations of two weeds, Lolium Persicum (Ryegrass) and Sinapis arvensis (wild mustered), on growth characteristics of two barley varieties was studied in the greenhouse using a completely randomized design with four replications. Test factors consisted of two barley varieties (Valfajr and Rehane), three weed organs (root, stalk, leaf) and four concentrations of extracts of weed organs (25, 50, 75 and control or distilled water). After the preparation of extracts of different weed organs with different concentrations, their effect on growth characteristics of barley plant was evaluated. Finally, seedling length, rootlet length caulicle length, wet weight of seedling, dry weight of seedling were measured. Also, the above two seeds had significant effects on the two strains of barley and could influence growth characteristics of barley. Based on the results of present study, one can argue that Ryegrass (Lolium Persicum) and wild mustard (Sinapis arvensis) can strongly affect germination, growth and performance of barley through production of chemical materials with allelopathic properties, leading unfavorable growth and product yield. (author)

  11. Inheritance patterns of the response to in vitro doubled haploid induction in perennial ryegrass (Lolium perenne L.)

    Czech Academy of Sciences Publication Activity Database

    Begheyn, R. F.; Roulund, N.; Vangsgaard, K.; Kopecký, David; Studer, B.

    2017-01-01

    Roč. 130, č. 3 (2017), s. 667-679 ISSN 0167-6857 Institutional support: RVO:61389030 Keywords : Androgenesis * Androgenic capacity * Anther culture * Doubled haploid (DH) * Perennial ryegrass (Lolium perenne L.) Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Plant sciences, botany Impact factor: 2.002, year: 2016

  12. First Case of Glufosinate-Resistant Rigid Ryegrass (Lolium rigidum Gaud. in Greece

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    Ilias S. Travlos

    2018-03-01

    Full Text Available Repeated applications of the same herbicide(s, which are characterized by the same mode of action, increase selection pressure, which in turn favours the evolution of herbicide-resistant weeds. Glufosinate is a broad-spectrum non-selective herbicide being used for weed control for many years around the world. Rigid ryegrass (Lolium rigidum Gaud. is an economically important grass weed in Greece. Recent complaints by growers about control failure of rigid ryegrass with glufosinate require further investigation and have been the basis of this study. The objectives of this study were to confirm the existence of glufosinate-resistant L. rigidum in Greece and evaluate the effect of L. rigidum growth stage on glufosinate efficacy. Twenty populations of rigid ryegrass from Greece were sampled from five regions, and whole plant dose–response studies were conducted for five populations under controlled conditions with eight rates of glufosinate (0.0, 0.098, 0.187, 0.375, 0.75, 1.5, 3.0, and 6.0 kg a.i. ha−1. Glufosinate resistance was confirmed in three out of five populations with the level of resistance ranging from three-to seven-fold compared with the susceptible populations based on above-ground biomass reduction. Results also revealed that the level of glufosinate-resistance of rigid ryegrass was dependent on the growth stage at which it was applied.

  13. Genetic Loci Governing Androgenic Capacity in Perennial Ryegrass (Lolium perenne L.

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    Rachel F. Begheyn

    2018-06-01

    Full Text Available Immature pollen can be induced to switch developmental pathways from gametogenesis to embryogenesis and subsequently regenerate into homozygous, diploid plants. Such androgenic production of doubled haploids is particularly useful for species where inbreeding is hampered by effective self-incompatibility systems. Therefore, increasing the generally low androgenic capacity of perennial ryegrass (Lolium perenne L. germplasm would enable the efficient production of homozygous plant material, so that a more effective exploitation of heterosis through hybrid breeding schemes can be realized. Here, we present the results of a genome-wide association study in a heterozygous, multiparental population of perennial ryegrass (n = 391 segregating for androgenic capacity. Genotyping-by-sequencing was used to interrogate gene- dense genomic regions and revealed over 1,100 polymorphic sites. Between one and 10 quantitative trait loci (QTL were identified for anther response, embryo and total plant production, green and albino plant production and regeneration. Most traits were under polygenic control, although a major QTL on linkage group 5 was associated with green plant regeneration. Distinct genetic factors seem to affect green and albino plant recovery. Two intriguing candidate genes, encoding chromatin binding domains of the developmental phase transition regulator, Polycomb Repressive Complex 2, were identified. Our results shed the first light on the molecular mechanisms behind perennial ryegrass microspore embryogenesis and enable marker-assisted introgression of androgenic capacity into recalcitrant germplasm of this forage crop of global significance.

  14. EST-derived SSR markers used as anchor loci for the construction of a consensus linkage map in ryegrass (Lolium spp.

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    Studer Bruno

    2010-08-01

    Full Text Available Abstract Background Genetic markers and linkage mapping are basic prerequisites for marker-assisted selection and map-based cloning. In the case of the key grassland species Lolium spp., numerous mapping populations have been developed and characterised for various traits. Although some genetic linkage maps of these populations have been aligned with each other using publicly available DNA markers, the number of common markers among genetic maps is still low, limiting the ability to compare candidate gene and QTL locations across germplasm. Results A set of 204 expressed sequence tag (EST-derived simple sequence repeat (SSR markers has been assigned to map positions using eight different ryegrass mapping populations. Marker properties of a subset of 64 EST-SSRs were assessed in six to eight individuals of each mapping population and revealed 83% of the markers to be polymorphic in at least one population and an average number of alleles of 4.88. EST-SSR markers polymorphic in multiple populations served as anchor markers and allowed the construction of the first comprehensive consensus map for ryegrass. The integrated map was complemented with 97 SSRs from previously published linkage maps and finally contained 284 EST-derived and genomic SSR markers. The total map length was 742 centiMorgan (cM, ranging for individual chromosomes from 70 cM of linkage group (LG 6 to 171 cM of LG 2. Conclusions The consensus linkage map for ryegrass based on eight mapping populations and constructed using a large set of publicly available Lolium EST-SSRs mapped for the first time together with previously mapped SSR markers will allow for consolidating existing mapping and QTL information in ryegrass. Map and markers presented here will prove to be an asset in the development for both molecular breeding of ryegrass as well as comparative genetics and genomics within grass species.

  15. Comparison of the fatty acid composition of fresh and ensiled perennial ryegrass (Lolium perenne L.), affected by cultivar and regrowth interval

    NARCIS (Netherlands)

    Elgersma, A.; Ellen, G.; Horst, van der H.; Muuse, B.G.; Boer, H.; Tamminga, S.

    2003-01-01

    Two experiments were conducted to evaluate the effects of grass cultivar and regrowth stage on the fatty acid (FA) profile in fresh and ensiled perennial ryegrass (Lolium perenne L.). The Experiment 1 compared the composition of fresh grass with that of pre-wilted ensiled material of six cultivars,

  16. Spring nitrogen fertilization of ryegrass-bermudagrass for phytoremediation of phosphorus-enriched soils

    Science.gov (United States)

    Nitrogen fertilization of forage grasses is critical for optimizing biomass and utilization of manure soil nutrients. Field studies were conducted in 2007-09 to determine the effects of spring N fertilization on amelioration of high soil P when cool-season, annual ryegrass (Lolium multiflorum L.) is...

  17. Complete chloroplast genome sequence of a major allogamous forage species, perennial ryegrass (Lolium perenne L.).

    Science.gov (United States)

    Diekmann, Kerstin; Hodkinson, Trevor R; Wolfe, Kenneth H; van den Bekerom, Rob; Dix, Philip J; Barth, Susanne

    2009-06-01

    Lolium perenne L. (perennial ryegrass) is globally one of the most important forage and grassland crops. We sequenced the chloroplast (cp) genome of Lolium perenne cultivar Cashel. The L. perenne cp genome is 135 282 bp with a typical quadripartite structure. It contains genes for 76 unique proteins, 30 tRNAs and four rRNAs. As in other grasses, the genes accD, ycf1 and ycf2 are absent. The genome is of average size within its subfamily Pooideae and of medium size within the Poaceae. Genome size differences are mainly due to length variations in non-coding regions. However, considerable length differences of 1-27 codons in comparison of L. perenne to other Poaceae and 1-68 codons among all Poaceae were also detected. Within the cp genome of this outcrossing cultivar, 10 insertion/deletion polymorphisms and 40 single nucleotide polymorphisms were detected. Two of the polymorphisms involve tiny inversions within hairpin structures. By comparing the genome sequence with RT-PCR products of transcripts for 33 genes, 31 mRNA editing sites were identified, five of them unique to Lolium. The cp genome sequence of L. perenne is available under Accession number AM777385 at the European Molecular Biology Laboratory, National Center for Biotechnology Information and DNA DataBank of Japan.

  18. Perennial ryegrass for dairy cows: effects of cultivar on herbage intake during grazing

    NARCIS (Netherlands)

    Smit, H.J.

    2005-01-01

    Keywords:Perennial ryegrass, Lolium perenne , sward morphology, sward cutting, n-alkanes, herbage intake, selection, preference.Perennial ryegrass ( Lolium perenne L.) is the most important species for feeding dairy cows. The majority of the farmers in the Netherlands graze their

  19. The genus Lolium : taxonomy and genetic resources

    NARCIS (Netherlands)

    Loos, B.P.

    1994-01-01

    Several aspects of variation within the genus Lolium, and more in detail within Lolium perenne (perennial ryegrass) have been highlighted. As the results are extensively discussed in each chapter, the general discussion is focused on two aspects of

  20. A statistical mixture model for estimating the proportion of unreduced pollen grains in perennial ryegrass (Lolium perenne L.) via the size of pollen grains

    NARCIS (Netherlands)

    Jansen, R.C.; Nijs, A.P.M. den

    1993-01-01

    The size of pollen grains is commonly used to indicate the ploidy level of pollen grains. In this paper observations of the diameter of pollen grains are evaluated from one diploid accession of perennial ryegrass (Lolium perenne L.), which was expected to produce diploid (unreduced) pollen grains in

  1. Controle químico de azevém (Lolium multiflorum L. na cultura do trigo Chemical control of ryegrass (Lolium multiflorum L. in wheat

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    N.G. Fleck

    1978-09-01

    relativa seletividade ao trigo, exerceram inadequada atividade de pós-emergência sobre o azevém. O tratamento diuron mostrou comportamento insuficiente tanto em relação ao controle do azevém, quanto ao rendimento do trigo. Os herbicidas cianazina e terbutrina proporcionaram adequado controle do azevém; contudo, suas seletividades à cultura do trigo foram muito reduzidas, além de terem causado diminuição no poder germinativo das sementes de trigo colhidas das parcelas tratadas com estes herbicidas.A field experiment was conducted during 1977 in the Central Depression region of Rio Grande do Sul to evaluate herbicide treatments to selectively control ryegrass (Lolium multif lorum L. in wheat (line E-7414, as well as to establish the competition levels between both grasses. The herbicides chlorbromuron, chlortoluron, cyanazine, diclofop, diuron, metoxuron, and terbutryn were compared with the control treatments: wheat without ryegrass, wheat competing with ryegrass, and ryegrass alone. All the herbicides were applied in postemergence, when wheat plants in the stage of 3-4 leaves, and ryegrass presented 1-3 leaves. It was found that, when ryegrass infestation was not controled by any means, an average reduction of 52% occurred in wheat seed yield. On the other hand, the wheat population which competed with ryegrass plants, caused a decrease in the order of 42% on ryegrass dry matter production. It was observed that all the herbicides presented phytotoxicity, causing from light to very severe injuries to wheat plants, depending on the product used; and that seed yields resulting from the chemical treatments were lower than that of the check plot free of ryegrass. However, all the compounds tested presented significant post-emergence activity, showing potential for ryegrass control. As well as ryegrass dry matter production, also visual evaluation of ryegrass control were appropriate methods to measure the herbicide effect. Among the herbicides evaluated, diclofop was

  2. Validation of reference genes for quantitative RT-PCR studies of gene expression in perennial ryegrass (Lolium perenne L.

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    Thrush Anthony

    2010-01-01

    Full Text Available Abstract Background Perennial ryegrass (Lolium perenne L. is an important pasture and turf crop. Biotechniques such as gene expression studies are being employed to improve traits in this temperate grass. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR is among the best methods available for determining changes in gene expression. Before analysis of target gene expression, it is essential to select an appropriate normalisation strategy to control for non-specific variation between samples. Reference genes that have stable expression at different biological and physiological states can be effectively used for normalisation; however, their expression stability must be validated before use. Results Existing Serial Analysis of Gene Expression data were queried to identify six moderately expressed genes that had relatively stable gene expression throughout the year. These six candidate reference genes (eukaryotic elongation factor 1 alpha, eEF1A; TAT-binding protein homolog 1, TBP-1; eukaryotic translation initiation factor 4 alpha, eIF4A; YT521-B-like protein family protein, YT521-B; histone 3, H3; ubiquitin-conjugating enzyme, E2 were validated for qRT-PCR normalisation in 442 diverse perennial ryegrass (Lolium perenne L. samples sourced from field- and laboratory-grown plants under a wide range of experimental conditions. Eukaryotic EF1A is encoded by members of a multigene family exhibiting differential expression and necessitated the expression analysis of different eEF1A encoding genes; a highly expressed eEF1A (h, a moderately, but stably expressed eEF1A (s, and combined expression of multigene eEF1A (m. NormFinder identified eEF1A (s and YT521-B as the best combination of two genes for normalisation of gene expression data in perennial ryegrass following different defoliation management in the field. Conclusions This study is unique in the magnitude of samples tested with the inclusion of numerous field-grown samples

  3. The genus Lolium : taxonomy and genetic resources

    OpenAIRE

    Loos, B.P.

    1994-01-01

    Several aspects of variation within the genus Lolium, and more in detail within Lolium perenne (perennial ryegrass) have been highlighted. As the results are extensively discussed in each chapter, the general discussion is focused on two aspects of the research.

    Speciation
    It is clear that the genus Lolium is a very variable genus. The variation within the species reduces the clarity o...

  4. Ergot alkaloid intoxication in perennial ryegrass (Lolium perenne): an emerging animal health concern in Ireland?

    Science.gov (United States)

    Canty, Mary J; Fogarty, Ursula; Sheridan, Michael K; Ensley, Steve M; Schrunk, Dwayne E; More, Simon J

    2014-01-01

    Four primary mycotoxicosis have been reported in livestock caused by fungal infections of grasses or cereals by members of the Clavicipitaceae family. Ergotism (generally associated with grasses, rye, triticale and other grains) and fescue toxicosis (associated with tall fescue grass, Festuca arundinacea) are both caused by ergot alkaloids, and referred to as 'ergot alkaloid intoxication'. Ryegrass staggers (associated with perennial ryegrass Lolium perenne) is due to intoxication with an indole-diperpene, Lolitrem B, and metabolites. Fescue-associated oedema, recently described in Australia, may be associated with a pyrrolizidine alkaloid, N-acetyl norloline. Ergotism, caused by the fungus Claviceps purpurea, is visible and infects the outside of the plant seed. Fescue toxicosis and ryegrass staggers are caused by Neotyphodium coenophalium and N. lolii, respectively. Fescue-associated oedema has been associated with tall fescue varieties infected with a specific strain of N. coenophialum (AR542, Max P or Max Q). The name Neotyphodium refers to asexual derivatives of Epichloë spp., which have collectively been termed the epichloë fungi. These fungi exist symbiotically within the grass and are invisible to the naked eye. The primary toxicological effect of ergot alkaloid involves vasoconstriction and/or hypoprolactinaemia. Ingestion of ergot alkaloid by livestock can cause a range of effects, including poor weight gain, reduced fertility, hyperthermia, convulsions, gangrene of the extremities, and death. To date there are no published reports, either internationally or nationally, reporting ergot alkaloid intoxication specifically associated with perennial ryegrass endophytes. However, unpublished reports from the Irish Equine Centre have identified a potential emerging problem of ergot alkaloid intoxication with respect to equines and bovines, on primarily perennial ryegrass-based diets. Ergovaline has been isolated in varying concentrations in the herbage of a

  5. Effects of seeding ryegrass (Lolium multiflorum) on vegetation recovery following fire in a ponderosa pine (Pinus ponderosa) forest

    Science.gov (United States)

    Barclay, Angela D.; Betancourt, Julio L.; Allen, Craig D.

    2004-01-01

    Forty-nine vegetation transects were measured in 1997 and 1998 to determine the impact of grass seeding after the 1996 Dome Fire, which burned almost 6900 ha of ponderosa pine (Pinus ponderosa Lawson) forest in the Jemez Mountains of north-central New Mexico. High- and moderate-burned areas in Santa Fe National Forest were seeded with a mixture that included the exotic ryegrass (Lolium multiflorum Lam.). Adjacent burned areas of Bandelier National Monument were not seeded, and were used as a control in the post-seeding study. On the seeded plots, foliar cover of ryegrass declined from 1997 to 1998 due to self-inhibition and/or reduced precipitation from 1997 to 1998. Foliar cover and diversity of native forbs were greater in 1997 than 1998, probably due to a wet growing season in 1997. Cover, species richness, and diversity of native forbs were highest in non-seeded areas of moderate- and high-burn intensities. Regeneration and survivorship of conifer seedlings decreased as ryegrass cover increased, particularly in areas of high-burn intensity. Exotic plant cover, mostly horseweed [Conyza canadensis (L.) Cronq.], increased from 1997 to 1998 in non-seeded areas of moderate- and high-burn intensity. Both the initial success of seeding and the eventual impacts on native vegetation were strongly modulated by climate variability.

  6. Genetic and Environmental Variance Among F2 Families in a Commercial Breeding Program for Perennial Ryegrass (Lolium perenne L.)

    DEFF Research Database (Denmark)

    Fé, Dario; Greve-Pedersen, Morten; Jensen, Christian Sig

    2013-01-01

    In the joint project “FORAGESELECT”, we aim to implement Genome Wide Selection (GWS) in breeding of perennial ryegrass (Lolium perenne L.), in order to increase genetic response in important agronomic traits such as yield, seed production, stress tolerance and disease resistance, while decreasing...... of this study was to estimate the genetic and environmental variance in the training set composed of F2 families selected from a ten year breeding period. Variance components were estimated on 1193 of those families, sown in 2001, 2003 and 2005 in five locations around Europe. Families were tested together...

  7. Physiological effects of magnetite (Fe3O4) nanoparticles on perennial ryegrass (Lolium perenne L.) and pumpkin (Cucurbita mixta) plants.

    Science.gov (United States)

    Wang, Huanhua; Kou, Xiaoming; Pei, Zhiguo; Xiao, John Q; Shan, Xiaoquan; Xing, Baoshan

    2011-03-01

    To date, knowledge gaps and associated uncertainties remain unaddressed on the effects of nanoparticles (NPs) on plants. This study was focused on revealing some of the physiological effects of magnetite (Fe(3)O(4)) NPs on perennial ryegrass (Lolium perenne L.) and pumpkin (Cucurbita mixta cv. white cushaw) plants under hydroponic conditions. This study for the first time reports that Fe(3)O(4) NPs often induced more oxidative stress than Fe(3)O(4) bulk particles in the ryegrass and pumpkin roots and shoots as indicated by significantly increased: (i) superoxide dismutase and catalase enzyme activities, and (ii) lipid peroxidation. However, tested Fe(3)O(4) NPs appear unable to be translocated in the ryegrass and pumpkin plants. This was supported by the following data: (i) No magnetization was detected in the shoots of either plant treated with 30, 100 and 500 mg l(-1) Fe(3)O(4) NPs; (ii) Fe K-edge X-ray absorption spectroscopic study confirmed that the coordination environment of Fe in these plant shoots was similar to that of Fe-citrate complexes, but not to that of Fe(3)O(4) NPs; and (iii) total Fe content in the ryegrass and pumpkin shoots treated with Fe(3)O(4) NPs was not significantly increased compared to that in the control shoots.

  8. Phytoextraction of metals and rhizoremediation of PAHs in co-contaminated soil by co-planting of Sedum alfredii with ryegrass (Lolium perenne) or castor (Ricinus communis).

    Science.gov (United States)

    Wang, Kai; Huang, Huagang; Zhu, Zhiqiang; Li, Tingqiang; He, Zhenli; Yang, Xiaoe; Alva, Ashok

    2013-01-01

    A pot experiment was conducted to investigate the potential for phytoextraction of heavy metals and rhizoremediation of polycyclic aromatic hydrocarbons (PAHs) in co-contaminated soil by co-planting a cadmium/zinc (Cd/Zn) hyperaccumulator and lead (Pb) accumulator Sedum alfredii with ryegrass (Lolium perenne) or castor (Ricinus communis). Co-planting with castor decreased the shoot biomass of S. alfredii as compared to that in monoculture. Cadmium concentration in S. alfredii shoot significantly decreased when grown with ryegrass or castor as compared to that in monoculture. However, no reduction of Zn or Pb concentration in S. alfredii shoot was detected in co-planting treatments. Total removal of either Cd, Zn, or Pb by plants was similar across S. alfredii monoculture or co-planting with ryegrass or castor, except enhanced Pb removal in S. alfredii and ryegrass co-planting treatment. Co-planting of S. alfredii with ryegrass or castor significantly enhanced the pyrene and anthracene dissipation as compared to that in the bare soil or S. alfredii monoculture. This appears to be due to the increased soil microbial population and activities in both co-planting treatments. Co-planting of S. alfredii with ryegrass or castor provides a promising strategy to mitigate both metal and PAH contaminants from co-contaminated soils.

  9. Immunological cross-reactivity of the major allergen from perennial ryegrass (Lolium perenne), Lol p I, and the cysteine proteinase, bromelain.

    Science.gov (United States)

    Pike, R N; Bagarozzi, D; Travis, J

    1997-04-01

    Antibodies prepared in rabbits against the major allergen from ryegrass (Lolium perenne), Lol p I, cross-reacted with the cysteine proteinase bromelain from pineapple and vice versa. Deglycosylation of the proteins showed that the cross-reaction was based on recognition of the carbohydrate moiety of the allergen, but for bromelain the cross-reaction was most likely due to a combination of factors. The results indicate that the carbohydrate residues from these allergens play an important role in cross-reactions found between them and possibly those from other species.

  10. Genetic characterisation of seed yield and fertility traits in perennial ryegrass (Lolium perenne L.)

    DEFF Research Database (Denmark)

    Studer, Bruno; Jensen, Louise Bach; Hentrup, Stephan

    2008-01-01

    A population. Path analysis partitioned the direct and indirect effects of seed yield components on seed yield per plant. Seed yield per panicle showed the highest effect on total seed yield. The adjusted mean values of each trait and a genetic linkage map consisting of 97 anonymous and 85 gene associated DNA......Seed yield is a trait of major interest for the key grassland species Lolium perenne L. An F2 mapping population of perennial ryegrass (VrnA), recently characterised for vernalisation response, was assessed in a glasshouse for traits related to seed yield based on a lattice design with four...... replications over 2 years. The traits heading date, plant height, length of panicles, number of panicles per plant, seed yield per panicle, flag leaf length, flag leaf width and seed yield per plant revealed repeatabilities ranging from 41 to 76% and a considerable amount of genetic variation in the Vrn...

  11. Remediation of anthracene in mycorrhizospheric soil using ryegrass ...

    African Journals Online (AJOL)

    ... such as polycyclic aromatic hydrocarbons (PAHs), pesticides and radionuclides. ... In the present study, biodegradation of anthracene was studied using ryegrass in ... bioremediation, Lolium multiflorum, arbuscular mycorrhizal fungi, PAHs.

  12. Milk production potential of two ryegrass cultivars with different total ...

    African Journals Online (AJOL)

    The aim of the study was to compare a new Italian ryegrass (Lolium multiflorum) cultivar (Enhancer), bred to contain a high total non-structural carbohydrate content, with the cultivar, Dargle, in terms of dry matter (DM) production, nutritional value, carrying capacity and milk production. The ryegrass cultivars were sown (25 ...

  13. Seasonal Variation of Provitamin D2 and Vitamin D2 in Perennial Ryegrass (Lolium perenne L.)

    DEFF Research Database (Denmark)

    Jäpelt, Rie Bak; Didion, Thomas; Smedsgaard, Jørn

    2011-01-01

    Ergosterol (provitamin D(2)) is converted to vitamin D(2) in grass by exposure to UV light. Six varieties of perennial ryegrass (Lolium perenne L.) were harvested four times during the season, and the contents of vitamin D(2) and ergosterol were analyzed by a sensitive and selective liquid...... chromatography tandem mass spectrometry method. Weather factors were recorded, and a principal component analysis was performed to study which factors were important for the formation of vitamin D(2). The results suggest that a combination of weather factors is involved and that the contents of ergosterol...... and vitamin D(2) change more than a factor of 10 during the season. These results demonstrate that grass potentially can be a significant source of vitamin D for grazing animals and animals fed on silage and hay....

  14. Comparison of herbage yield, nutritive value and ensilability traits of three ryegrass species evaluated for the Irish Recommended List

    Directory of Open Access Journals (Sweden)

    Burns G. A.

    2015-06-01

    Full Text Available This study examined 169 of the newest varieties of three ryegrass species, perennial (Lolium perenne L., Italian (Lolium multiflorum Lam. and hybrid (Lolium boucheanum Kunth, from Recommended List trials in Ireland. The traits examined were yield, dry matter concentration, three nutritive value traits (in vitro dry matter digestibility, water-soluble carbohydrate on a dry matter basis and crude protein concentration and two ensilability traits (buffering capacity and water soluble carbohydrate concentration on an aqueous phase basis. Varietal monocultures of each species underwent a six cut combined simulated grazing and silage management in each of two years following sowing. Perennial ryegrass yielded less than both other species in one-year-old swards, but less than only Italian ryegrass in two-year-old swards, but generally had the higher in vitro dry matter digestibility and crude protein values. Italian ryegrass displayed the most favourable ensilability characteristics of the three species with perennial ryegrass less favourable and hybrid ryegrass intermediate. Overall, despite the high yields and favourable nutritive value and ensilability traits recorded, the general differences between the three ryegrass species studied were in line with industry expectations. These findings justify assessing the nutritive value and ensilability of ryegrass species, in addition to yield, to allow farmers select species that match farming enterprise requirements.

  15. Integrated assessment of air pollution by metals and source apportionment using ryegrass (Lolium multiflorum Lam.) in southern Brazil.

    Science.gov (United States)

    Illi, Júlia Carolina; Vancetta, Tafael; Alves, Darlan Daniel; Osório, Daniela Montanari Migliavacca; Bianchin, Liane; de Quevedo, Daniela Müller; Juchem, Fernando

    2017-01-01

    One of the biggest environmental problems existing today is air pollution, which is characterized by the presence of toxic gases and metal pollutants, the latter of which is generally associated with emissions of particulate matter (PM) from industries or automotive vehicles. Biomonitoring is a method that can be used to assess air pollution levels because it makes it possible to determine what effects these air pollutants cause in living organisms and their responses. The species Lolium multiflorum Lam., known as ryegrass, is considered a good bioindicator of metals, since it accumulates these substances during exposure. This study proposes to conduct an integrated assessment of air quality using two different monitoring methodologies: biomonitoring with L. multiflorum and active monitoring in areas with different levels of urbanization and industrialization. Concentrations found in ryegrass plants revealed high levels of Pb, Cr, Zn, and Cu, indicating that vehicular and industrial emissions were the main sources of pollution. Analysis of PM also revealed soot and biogenic particles, which can transport metals. Therefore, with the proposed method, the anthropogenic impact on air pollution in the investigated area could be clearly demonstrated.

  16. Comparative proteomic analyses reveal the proteome response to short-term drought in Italian ryegrass (Lolium multiflorum.

    Directory of Open Access Journals (Sweden)

    Ling Pan

    Full Text Available Drought is a major abiotic stress that impairs growth and productivity of Italian ryegrass. Comparative analysis of drought responsive proteins will provide insight into molecular mechanism in Lolium multiflorum drought tolerance. Using the iTRAQ-based approach, proteomic changes in tolerant and susceptible lines were examined in response to drought condition. A total of 950 differentially accumulated proteins was found to be involved in carbohydrate metabolism, amino acid metabolism, biosynthesis of secondary metabolites, and signal transduction pathway, such as β-D-xylosidase, β-D-glucan glucohydrolase, glycerate dehydrogenase, Cobalamin-independent methionine synthase, glutamine synthetase 1a, Farnesyl pyrophosphate synthase, diacylglycerol, and inositol 1, 4, 5-trisphosphate, which might contributed to enhance drought tolerance or adaption in Lolium multiflorum. Interestingly, the two specific metabolic pathways, arachidonic acid and inositol phosphate metabolism including differentially accumulated proteins, were observed only in the tolerant lines. Cysteine protease cathepsin B, Cysteine proteinase, lipid transfer protein and Aquaporin were observed as drought-regulated proteins participating in hydrolysis and transmembrane transport. The activities of phospholipid hydroperoxide glutathione peroxidase, peroxiredoxin, dehydroascorbate reductase, peroxisomal ascorbate peroxidase and monodehydroascorbate reductase associated with alleviating the accumulation of reactive oxygen species in stress inducing environments. Our results showed that drought-responsive proteins were closely related to metabolic processes including signal transduction, antioxidant defenses, hydrolysis, and transmembrane transport.

  17. The Perennial Ryegrass GenomeZipper – Targeted Use of Genome Resources for Comparative Grass Genomics

    DEFF Research Database (Denmark)

    Pfeiffer, Matthias; Martis, Mihaela; Asp, Torben

    2013-01-01

    (Lolium perenne) genome on the basis of conserved synteny to barley (Hordeum vulgare) and the model grass genome Brachypodium (Brachypodium distachyon) as well as rice (Oryza sativa) and sorghum (Sorghum bicolor). A transcriptome-based genetic linkage map of perennial ryegrass served as a scaffold......Whole-genome sequences established for model and major crop species constitute a key resource for advanced genomic research. For outbreeding forage and turf grass species like ryegrasses (Lolium spp.), such resources have yet to be developed. Here, we present a model of the perennial ryegrass...... to establish the chromosomal arrangement of syntenic genes from model grass species. This scaffold revealed a high degree of synteny and macrocollinearity and was then utilized to anchor a collection of perennial ryegrass genes in silico to their predicted genome positions. This resulted in the unambiguous...

  18. A DArT marker genetic map of perennial ryegrass (Lolium perenne L.) integrated with detailed comparative mapping information; comparison with existing DArT marker genetic maps of Lolium perenne, L. multiflorum and Festuca pratensis.

    Science.gov (United States)

    King, Julie; Thomas, Ann; James, Caron; King, Ian; Armstead, Ian

    2013-07-03

    Ryegrasses and fescues (genera, Lolium and Festuca) are species of forage and turf grasses which are used widely in agricultural and amenity situations. They are classified within the sub-family Pooideae and so are closely related to Brachypodium distachyon, wheat, barley, rye and oats. Recently, a DArT array has been developed which can be used in generating marker and mapping information for ryegrasses and fescues. This represents a potential common marker set for ryegrass and fescue researchers which can be linked through to comparative genomic information for the grasses. A F2 perennial ryegrass genetic map was developed consisting of 7 linkage groups defined by 1316 markers and deriving a total map length of 683 cM. The marker set included 866 DArT and 315 gene sequence-based markers. Comparison with previous DArT mapping studies in perennial and Italian ryegrass (L. multiflorum) identified 87 and 105 DArT markers in common, respectively, of which 94% and 87% mapped to homoeologous linkage groups. A similar comparison with meadow fescue (F. pratensis) identified only 28 DArT markers in common, of which c. 50% mapped to non-homoelogous linkage groups. In L. perenne, the genetic distance spanned by the DArT markers encompassed the majority of the regions that could be described in terms of comparative genomic relationships with rice, Brachypodium distachyon, and Sorghum bicolor. DArT markers are likely to be a useful common marker resource for ryegrasses and fescues, though the success in aligning different populations through the mapping of common markers will be influenced by degrees of population interrelatedness. The detailed mapping of DArT and gene-based markers in this study potentially allows comparative relationships to be derived in future mapping populations characterised using solely DArT markers.

  19. Arsenic extractability and uptake by velvetgrass Holcus lanatus and ryegrass Lolium perenne in variously treated soils polluted by tailing spills.

    Science.gov (United States)

    Karczewska, Anna; Lewińska, Karolina; Gałka, Bernard

    2013-11-15

    Phytostabilization should be considered as an appropriate phytoremediation technique to restore the area affected by tailing spills in Zloty Stok, where arsenic ores were mined and processed for several centuries. The study aimed to compare the suitability of velvetgrass (Holcus lanatus L.) and ryegrass (Lolium perenne L.) for development of plant cover in that area. Various treatments commonly applied to support phytostabilization were examined. A pot experiment was carried out to assess the effects of soil amendment with phosphate (P), sewage sludge (SS) and iron salts (Fe) on arsenic extractability and its uptake by grass. Four kinds of soil material, containing 356-5350 mg kg(-1) As, were examined. Velvetgrass proved to be more resistant than ryegrass to the toxicity of soil arsenic. Ammonium sulphate extractability of As in soils correlated well with As concentrations in the biomass of both grass species. In three of four tested soils, application of Fe failed to decrease As extractability and to reduce its concentrations in the aboveground parts of grasses. Application of P and SS resulted in increased As solubility in soils, but their effects on plant biomass and As uptake were ambiguous. SS had a strong beneficial influence on the growth of velvetgrass, while such an effect was not observed for ryegrass. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Transcriptional responses of Italian ryegrass during interaction with Xanthomonas translucens pv. graminis reveal novel candidate genes for bacterial wilt resistance

    DEFF Research Database (Denmark)

    Wichmann, Fabienne; Asp, Torben; Widmer, Franko

    2011-01-01

    Xanthomonas translucens pv. graminis (Xtg) causes bacterial wilt, a severe disease of forage grasses such as Italian ryegrass (Lolium multiflorum Lam.). In order to gain a more detailed understanding of the genetic control of resistance mechanisms and to provide prerequisites for marker assisted...... selection, the partial transcriptomes of two Italian ryegrass genotypes, one resistant and one susceptible to bacterial wilt were compared at four time points after Xtg infection. A cDNA microarray developed from a perennial ryegrass (Lolium perenne) expressed sequence tag set consisting of 9,990 unique...

  1. Effect of D2O on growth properties and chemical structure of annual ryegrass (Lolium multiflorum)

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Barbara R [ORNL; Bali, Garima [Georgia Institute of Technology, Atlanta; Reeves, David T [ORNL; O' Neill, Hugh Michael [ORNL; Sun, Qining [Georgia Institute of Technology, Atlanta; Shah, Riddhi S [ORNL; Ragauskas, Arthur [Georgia Institute of Technology, Atlanta

    2014-01-01

    In present paper, we report the production and detailed structural analysis of deuterium-enriched rye grass (Lolium multiflorum) for neutron scattering experiments. An efficient method to produce deuterated biomass was developed by designing hydroponic perfusion chambers. In preliminary studies, the partial deuterated rye samples were grown in increasing levels of D2O to study the seed germination and the level of deuterium incorporation as a function of D2O concentration. Solution NMR method indicated 36.9 % deuterium incorporation in 50 % D2O grown annual rye samples and further significant increase in the deuterium incorporation level was observed by germinating the rye seedlings in H2O and growing in 50 % D2O inside the perfusion chambers. Moreover, in an effort to compare the substrate characteristics related to enzymatic hydrolysis on deuterated and protiated version of biomass, annual rye grown in 50 % D2O was selected for detailed biomass characterization studies. The compositional analyses, degree of polymerization and cellulose crystallinity were compared with its protiated control. The cellulose molecular weight indicated slight variation with deuteration; however, hemicellulose molecular weights and cellulose crystallinity remain unaffected with the deuteration. Besides the minor differences in biomass components, the development of deuterated biomass for neutron scattering application is essential to understand the complex biomass conversion processes.

  2. Arbuscular mycorrhiza enhanced arsenic resistance of both white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.) plants in an arsenic-contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Dong Yan; Zhu Yongguan [Department of Soil Environmental Science, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Smith, F. Andrew [Soil and Land Systems, School of Earth and Environmental Sciences, Waite Campus, University of Adelaide, Adelaide, SA 5005 (Australia); Wang Youshan [Institute of Plant Nutrition and Resources, Beijing Academy of Agriculture and Forestry, Beijing 100089 (China); Chen Baodong [Department of Soil Environmental Science, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China)], E-mail: bdchen@rcees.ac.cn

    2008-09-15

    In a compartmented cultivation system, white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.), with their roots freely intermingled, or separated by 37 {mu}m nylon mesh or plastic board, were grown together in an arsenic (As) contaminated soil. The influence of AM inoculation on plant growth, As uptake, phosphorus (P) nutrition, and plant competitions were investigated. Results showed that both plant species highly depended on mycorrhizas for surviving the As contamination. Mycorrhizal inoculation substantially improved plant P nutrition, and in contrast markedly decreased root to shoot As translocation and shoot As concentrations. It also showed that mycorrhizas affected the competition between the two co-existing plant species, preferentially benefiting the clover plants in term of nutrient acquisition and biomass production. Based on the present study, the role of AM fungi in plant adaptation to As contamination, and their potential use for ecological restoration of As contaminated soils are discussed. - Both white clover and ryegrass highly depend on the mycorrhizal associations for surviving heavy arsenic contamination.

  3. Arbuscular mycorrhiza enhanced arsenic resistance of both white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.) plants in an arsenic-contaminated soil

    International Nuclear Information System (INIS)

    Dong Yan; Zhu Yongguan; Smith, F. Andrew; Wang Youshan; Chen Baodong

    2008-01-01

    In a compartmented cultivation system, white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.), with their roots freely intermingled, or separated by 37 μm nylon mesh or plastic board, were grown together in an arsenic (As) contaminated soil. The influence of AM inoculation on plant growth, As uptake, phosphorus (P) nutrition, and plant competitions were investigated. Results showed that both plant species highly depended on mycorrhizas for surviving the As contamination. Mycorrhizal inoculation substantially improved plant P nutrition, and in contrast markedly decreased root to shoot As translocation and shoot As concentrations. It also showed that mycorrhizas affected the competition between the two co-existing plant species, preferentially benefiting the clover plants in term of nutrient acquisition and biomass production. Based on the present study, the role of AM fungi in plant adaptation to As contamination, and their potential use for ecological restoration of As contaminated soils are discussed. - Both white clover and ryegrass highly depend on the mycorrhizal associations for surviving heavy arsenic contamination

  4. A transcriptome map of perennial ryegrass (Lolium perenne L.

    Directory of Open Access Journals (Sweden)

    Studer Bruno

    2012-04-01

    Full Text Available Abstract Background Single nucleotide polymorphisms (SNPs are increasingly becoming the DNA marker system of choice due to their prevalence in the genome and their ability to be used in highly multiplexed genotyping assays. Although needed in high numbers for genome-wide marker profiles and genomics-assisted breeding, a surprisingly low number of validated SNPs are currently available for perennial ryegrass. Results A perennial ryegrass unigene set representing 9,399 genes was used as a reference for the assembly of 802,156 high quality reads generated by 454 transcriptome sequencing and for in silico SNP discovery. Out of more than 15,433 SNPs in 1,778 unigenes fulfilling highly stringent assembly and detection parameters, a total of 768 SNP markers were selected for GoldenGate genotyping in 184 individuals of the perennial ryegrass mapping population VrnA, a population being previously evaluated for important agronomic traits. A total of 592 (77% of the SNPs tested were successfully called with a cluster separation above 0.9. Of these, 509 (86% genic SNP markers segregated in the VrnA mapping population, out of which 495 were assigned to map positions. The genetic linkage map presented here comprises a total of 838 DNA markers (767 gene-derived markers and spans 750 centi Mogan (cM with an average marker interval distance of less than 0.9 cM. Moreover, it locates 732 expressed genes involved in a broad range of molecular functions of different biological processes in the perennial ryegrass genome. Conclusions Here, we present an efficient approach of using next generation sequencing (NGS data for SNP discovery, and the successful design of a 768-plex Illumina GoldenGate genotyping assay in a complex genome. The ryegrass SNPs along with the corresponding transcribed sequences represent a milestone in the establishment of genetic and genomics resources available for this species and constitute a further step towards molecular breeding

  5. Annual ryegrass toxicity in Thoroughbred horses in Ceres in the Western Cape Province, South Africa

    Directory of Open Access Journals (Sweden)

    J.D. Grewar

    2009-05-01

    Full Text Available An outbreak of annual ryegrass toxicity occurred on a Thoroughbred stud in Ceres in the Western Cape Province of South Africa. This is the 1st report of annual ryegrass toxicity in horses in South Africa, although the condition has been reported in cattle and sheep populations in the past. Annual ryegrass toxicity is characterised by a variety of neurological signs including tremors, convulsions, recumbency and in many cases death. The description of the outbreak includes the history, clinical presentation and treatment protocol administered during the outbreak. Various epidemiological variables and their influence in the outbreak are also considered.

  6. Arbuscular mycorrhizal fungi enhance both absorption and stabilization of Cd by Alfred stonecrop (Sedum alfredii Hance) and perennial ryegrass (Lolium perenne L.) in a Cd-contaminated acidic soil.

    Science.gov (United States)

    Hu, Junli; Wu, Shengchun; Wu, Fuyong; Leung, Ho Man; Lin, Xiangui; Wong, Ming Hung

    2013-10-01

    A greenhouse pot experiment was conducted to compare the phytoextraction efficiencies of Cd by hyper-accumulating Alfred stonecrop (Sedum alfredii Hance) and fast-growing perennial ryegrass (Lolium perenne L.) from a Cd-contaminated (1.6 mg kg(-1)) acidic soil, and their responses to the inoculations of two arbuscular mycorrhizal (AM) fungal strains, Glomus caledonium 90036 (Gc) and Glomus mosseae M47V (Gm). Ryegrass and stonecrop were harvested after growing for 9 and 27 wk, respectively. Without AM fungal inoculation, the weekly Cd extraction by stonecrop (8.0 μg pot(-1)) was 4.3 times higher than that by ryegrass (1.5 μg pot(-1)). Both Gc and Gm significantly increased (P soil acid phosphatase activities, and available P concentrations, and thereby plant P absorptions (except for Gm-inoculated ryegrass), shoot biomasses, and Cd absorptions (except for Gm-inoculated stonecrop), while only Gc-inoculated stonecrop significantly accelerated (P soil pH. The results suggested the potential application of hyper-accumulating Alfred stonecrop associated with AM fungi (notably Gc) for both extraction and stabilization of Cd in the in situ treatment of Cd-contaminated acidic soil. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Plant growth-promoting Burkholderia species isolated from annual ryegrass in Portuguese soils.

    Science.gov (United States)

    Castanheira, N; Dourado, A C; Kruz, S; Alves, P I L; Delgado-Rodríguez, A I; Pais, I; Semedo, J; Scotti-Campos, P; Sánchez, C; Borges, N; Carvalho, G; Barreto Crespo, M T; Fareleira, P

    2016-03-01

    To search for culturable Burkholderia species associated with annual ryegrass in soils from natural pastures in Portugal, with plant growth-promoting effects. Annual ryegrass seedlings were used to trap Burkholderia from two different soils in laboratory conditions. A combined approach using genomic fingerprinting and sequencing of 16S rRNA and recA genes resulted in the identification of Burkholderia strains belonging to the species Burkholderia graminis, Burkholderia fungorum and the Burkholderia cepacia complex. Most strains were able to solubilize mineral phosphate and to synthesize indole acetic acid; some of them could produce siderophores and antagonize the phytopathogenic oomycete, Phytophthora cinnamomi. A strain (G2Bd5) of B. graminis was selected for gnotobiotic plant inoculation experiments. The main effects were the stimulation of root growth and enhancement of leaf lipid synthesis and turnover. Fluorescence in situ hybridization and confocal laser microscopy evidenced that strain G2Bd5 is a rhizospheric and endophytic colonizer of annual ryegrass. This work revealed that annual ryegrass can naturally associate with members of the genus Burkholderia. A novel plant growth promoting strain of B. graminis was obtained. The novel strain belongs to the plant-associated Burkholderia cluster and is a promising candidate for exploitation as plant inoculant in field conditions. © 2015 The Society for Applied Microbiology.

  8. The perennial ryegrass GenomeZipper: targeted use of genome resources for comparative grass genomics.

    Science.gov (United States)

    Pfeifer, Matthias; Martis, Mihaela; Asp, Torben; Mayer, Klaus F X; Lübberstedt, Thomas; Byrne, Stephen; Frei, Ursula; Studer, Bruno

    2013-02-01

    Whole-genome sequences established for model and major crop species constitute a key resource for advanced genomic research. For outbreeding forage and turf grass species like ryegrasses (Lolium spp.), such resources have yet to be developed. Here, we present a model of the perennial ryegrass (Lolium perenne) genome on the basis of conserved synteny to barley (Hordeum vulgare) and the model grass genome Brachypodium (Brachypodium distachyon) as well as rice (Oryza sativa) and sorghum (Sorghum bicolor). A transcriptome-based genetic linkage map of perennial ryegrass served as a scaffold to establish the chromosomal arrangement of syntenic genes from model grass species. This scaffold revealed a high degree of synteny and macrocollinearity and was then utilized to anchor a collection of perennial ryegrass genes in silico to their predicted genome positions. This resulted in the unambiguous assignment of 3,315 out of 8,876 previously unmapped genes to the respective chromosomes. In total, the GenomeZipper incorporates 4,035 conserved grass gene loci, which were used for the first genome-wide sequence divergence analysis between perennial ryegrass, barley, Brachypodium, rice, and sorghum. The perennial ryegrass GenomeZipper is an ordered, information-rich genome scaffold, facilitating map-based cloning and genome assembly in perennial ryegrass and closely related Poaceae species. It also represents a milestone in describing synteny between perennial ryegrass and fully sequenced model grass genomes, thereby increasing our understanding of genome organization and evolution in the most important temperate forage and turf grass species.

  9. Agronomic behavior of annual ryegrass (Lolium multiflorum lam. in Rio Grande do Sul State

    Directory of Open Access Journals (Sweden)

    I. F. Conterato

    2016-09-01

    Full Text Available The objective of this study was to evaluate forage production and number of days to flowering in 15 common ryegrass populations, one population of the KLM 138 (Uruguay and Fepagro São Gabriel cultivars, and one local population in order to select germplasm with production potential. A randomized block design consisting of three replicates and repeated measures over time (cuts was adopted. Forage production was evaluated by cutting samples of 2 linear meters per plot. The forage samples of each plot were dried and weighed for the determination of total dry matter. A total dry matter subsample of each plot, in each cut, was used to estimate leaf percentage. The data were submitted to analysis of variance using mixed models and means were compared by the Tukey test (P0.05, indicating little variability for this trait in the populations studied during the growth cycle. The populations differed significantly in terms of leaf dry matter percentage (P=0.0002. The highest leaf percentages during the growth cycle were observed for cultivar KLM 138. However, populations of the common Uruguayan, Dom Pedrito and Vacaria cultivars also exhibited good leaf production and may be used for initial selection of new promising materials, considering that a higher percentage of leaves promotes better quality feed offered to animals. The variation in the number of days to flowering permits selection for different maturation cycles of common ryegrass.

  10. Cultivar by environment effects of perennial ryegrass cultivars selected for high water soluble carbohydrates managed under differing precipitation levels

    Science.gov (United States)

    Historic results of perennial ryegrass (Lolium perenne L.) breeding include improved disease resistance, biomass, and nutritional quality. Yet, lack of tolerance to water stress limits its wise use. Recent efforts to increase water soluble carbohydrate (WSC) content in perennial ryegrass may incre...

  11. Impacts of endophyte infection of ryegrass on rhizosphere metabolome and microbial community

    DEFF Research Database (Denmark)

    Wakelin, S.; Harrison, Scott James; Mander, C.

    2015-01-01

    37, within a genetically uniform breeding line of perennial ryegrass (Lolium perenne cv. Samson 11104) on the rhizosphere metabolome and the composition of the fungal, bacterial, and Pseudomonas communities. There were strong differences in the rhizosphere metabolomes between infested and non......-infested ryegrass strains (P=0.06). These were attributed to shifts in various n-alkane hydrocarbon compounds. The endophyte-associated alteration in rhizosphere metabolome was linked to changes in the total bacterial (P

  12. The genome and transcriptome of perennial ryegrass mitochondria

    DEFF Research Database (Denmark)

    Islam, Md. Shofiqul; Studer, Bruno; Byrne, Stephen

    2013-01-01

    Background: Perennial ryegrass (Lolium perenne L.) is one of the most important forage and turf grass species of temperate regions worldwide. Its mitochondrial genome is inherited maternally and contains genes that can influence traits of agricultural importance. Moreover, the DNA sequence...... and annotation of the complete mitochondrial genome from perennial ryegrass. Results: Intact mitochondria from perennial ryegrass leaves were isolated and used for mtDNA extraction. The mitochondrial genome was sequenced to a 167-fold coverage using the Roche 454 GS-FLX Titanium platform, and assembled...... of mitochondrial genomes has been established and compared for a large number of species in order to characterize evolutionary relationships.Therefore, it is crucial to understand the organization of the mitochondrial genome and how it varies between and within species. Here, we report the first de novo assembly...

  13. Water-soluble carbohydrates and in vitro digestibility of annual ryegrass (Lolium ridigum Gaudin) sown at varying densities

    NARCIS (Netherlands)

    Smouter, H.; Simpson, R.J.; Pear, G.R.

    1995-01-01

    An experiment is described in which the tiller density of microswards of Lolium rigidum was varied by altering planting density. The treatments were expected to alter the interplant competition for light and thus affect the concentration of water-soluble carbohydrates (WSC) of the grass swards.

  14. The Perennial Ryegrass GenomeZipper: Targeted Use of Genome Resources for Comparative Grass Genomics1[C][W

    Science.gov (United States)

    Pfeifer, Matthias; Martis, Mihaela; Asp, Torben; Mayer, Klaus F.X.; Lübberstedt, Thomas; Byrne, Stephen; Frei, Ursula; Studer, Bruno

    2013-01-01

    Whole-genome sequences established for model and major crop species constitute a key resource for advanced genomic research. For outbreeding forage and turf grass species like ryegrasses (Lolium spp.), such resources have yet to be developed. Here, we present a model of the perennial ryegrass (Lolium perenne) genome on the basis of conserved synteny to barley (Hordeum vulgare) and the model grass genome Brachypodium (Brachypodium distachyon) as well as rice (Oryza sativa) and sorghum (Sorghum bicolor). A transcriptome-based genetic linkage map of perennial ryegrass served as a scaffold to establish the chromosomal arrangement of syntenic genes from model grass species. This scaffold revealed a high degree of synteny and macrocollinearity and was then utilized to anchor a collection of perennial ryegrass genes in silico to their predicted genome positions. This resulted in the unambiguous assignment of 3,315 out of 8,876 previously unmapped genes to the respective chromosomes. In total, the GenomeZipper incorporates 4,035 conserved grass gene loci, which were used for the first genome-wide sequence divergence analysis between perennial ryegrass, barley, Brachypodium, rice, and sorghum. The perennial ryegrass GenomeZipper is an ordered, information-rich genome scaffold, facilitating map-based cloning and genome assembly in perennial ryegrass and closely related Poaceae species. It also represents a milestone in describing synteny between perennial ryegrass and fully sequenced model grass genomes, thereby increasing our understanding of genome organization and evolution in the most important temperate forage and turf grass species. PMID:23184232

  15. Effect of ryegrass (Lolium perenne L.) roots inoculation using different arbuscular mycorrhizal fungi (AMF) species on sorption of iron-cyanide (Fe-CN) complexes

    Science.gov (United States)

    Sut, Magdalena; Boldt-Burisch, Katja; Raab, Thomas

    2016-04-01

    Soils and groundwater on sites of the former Manufactured Gas Plants (MGPs) are contaminated with various complex iron-cyanides (Fe-CN). Phytoremediation is a promising tool in stabilization and remediation of Fe-CN affected soils, however, it can be a challenging task due to extreme adverse and toxic conditions. Phytoremediation may be enhanced via rhizosphere microbial activity, which can cooperate on the degradation, transformation and uptake of the contaminants. Recently, increasing number of scientist reports improved plants performance in the removal of toxic compounds with the support of arbuscular mycorrhizae fungi (AMF). Series of batch experiments using potassium hexacyanoferrate (II) solutions, in varying concentrations, were used to study the effect of ryegrass roots (Lolium perenne L.) inoculation with Rhizophagus irregularis and a mixture of Rhizophagus irregularis, Funneliformis mosseae, Rhizophagus aggregatus, and Claroideoglomus etunicatum on Fe-CN sorption. Results indicated significantly higher colonization of R. irregularis than for the mixture of AMF species on ryegrass roots. Sorption experiments revealed significantly higher reduction of total CN and free CN content in the mycorrhizal roots, indicating greater cyanide decrease in the treatment inoculated with R. irregularis. Our study indicates contribution of AM fungi in phytoremediation of Fe-CN contaminated soil.

  16. Effect of pre-grazing herbage mass on dairy cow performance, grass dry matter production and output from perennial ryegrass (Lolium perenne L.) pastures.

    Science.gov (United States)

    Wims, C M; Delaby, L; Boland, T M; O'Donovan, M

    2014-01-01

    A grazing study was undertaken to examine the effect of maintaining three levels of pre-grazing herbage mass (HM) on dairy cow performance, grass dry matter (DM) production and output from perennial ryegrass (Lolium perenne L.) pastures. Cows were randomly assigned to one of three pre-grazing HM treatments: 1150 - Low HM (L), 1400 - Medium HM (M) or 2000 kg DM/ha - High HM (H). Herbage accumulation under grazing was lowest (Ppastures required more grass silage supplementation during the grazing season (+73 kg DM/cow) to overcome pasture deficits due to lower pasture growth rates (Ppasture intake, although cows grazing the L pastures had to graze a greater daily area (Ppasture reduces pasture DM production and at a system level may increase the requirement for imported feed.

  17. Annual maize and perennial grass-clover strip cropping for increased resource use efficiency and productivity using organic farming practice as a model

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, Henrik; Johansen, Anders; Carter, Mette Sustmann

    2013-01-01

    A cropping system was designed to fulfill the increasing demand for biomass for food and energy without decreasing long term soil fertility. A field experiment was carried out including alternating strips of annual maize (Zea mays L.) and perennial ryegrass (Lolium perenne L.) – clover (Trifolium...

  18. Genetic linkage mapping in an F2 perennial ryegrass population using DArT markers

    Czech Academy of Sciences Publication Activity Database

    Tomaszewski, C.; Byrne, S. L.; Foito, A.; Kildea, S.; Kopecký, David; Doležel, Jaroslav; Heslop-Harrison, J. S.; Stewart, D.; Barth, S.

    2012-01-01

    Roč. 131, č. 2 (2012), s. 345-349 ISSN 0179-9541 Institutional research plan: CEZ:AV0Z50380511 Keywords : Lolium perenne * perennial ryegrass * genetic map Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.175, year: 2012

  19. Lambs Fed Fresh Winter Forage Rape (Brassica napus L.) Emit Less Methane than Those Fed Perennial Ryegrass (Lolium perenne L.), and Possible Mechanisms behind the Difference

    Science.gov (United States)

    Sun, Xuezhao; Henderson, Gemma; Cox, Faith; Molano, German; Harrison, Scott J.; Luo, Dongwen; Janssen, Peter H.; Pacheco, David

    2015-01-01

    The objectives of this study were to examine long-term effects of feeding forage rape (Brassica napus L.) on methane yields (g methane per kg of feed dry matter intake), and to propose mechanisms that may be responsible for lower emissions from lambs fed forage rape compared to perennial ryegrass (Lolium perenne L.). The lambs were fed fresh winter forage rape or ryegrass as their sole diet for 15 weeks. Methane yields were measured using open circuit respiration chambers, and were 22-30% smaller from forage rape than from ryegrass (averages of 13.6 g versus 19.5 g after 7 weeks, and 17.8 g versus 22.9 g after 15 weeks). The difference therefore persisted consistently for at least 3 months. The smaller methane yields from forage rape were not related to nitrate or sulfate in the feed, which might act as alternative electron acceptors, or to the levels of the potential inhibitors glucosinolates and S-methyl L-cysteine sulfoxide. Ruminal microbial communities in forage rape-fed lambs were different from those in ryegrass-fed lambs, with greater proportions of potentially propionate-forming bacteria, and were consistent with less hydrogen and hence less methane being produced during fermentation. The molar proportions of ruminal acetate were smaller and those of propionate were greater in forage rape-fed lambs, consistent with the larger propionate-forming populations and less hydrogen production. Forage rape contained more readily fermentable carbohydrates and less structural carbohydrates than ryegrass, and was more rapidly degraded in the rumen, which might favour this fermentation profile. The ruminal pH was lower in forage rape-fed lambs, which might inhibit methanogenic activity, shifting the rumen fermentation to more propionate and less hydrogen and methane. The significance of these two mechanisms remains to be investigated. The results suggest that forage rape is a potential methane mitigation tool in pastoral-based sheep production systems. PMID:25803688

  20. Allelopathic Potential of Switchgrass ( Panicum virgatum L.) on Perennial Ryegrass ( Lolium perenne L.) and Alfalfa ( Medicago sativa L.)

    Science.gov (United States)

    Shui, Junfeng; An, Yu; Ma, Yongqing; Ichizen, Nobumasa

    2010-10-01

    This study investigated allelopathy and its chemical basis in nine switchgrass ( Panicum virgatum L.) accessions. Perennial ryegrass ( Lolium perenne L.) and alfalfa ( Medicago sativa L.) were used as test species. Undiluted aqueous extracts (5 g plant tissue in 50 ml water) from the shoots and roots of most of the switchgrass accessions inhibited the germination and growth of the test species. However, the allelopathic effect of switchgrass declined when extracts were diluted 5- or 50-fold. Seedling growth was more sensitive than seed germination as an indicator of allelopathic effect. Allelopathic effect was related to switchgrass ecotype but not related to ploidy level. Upland accessions displayed stronger allelopathic potential than lowland accessions. The aqueous extract from one switchgrass accession was separated into phenols, organic acids, neutral chemicals, and alkaloids, and then these fractions were bioassayed to test for allelopathic potential. Alkaloids had the strongest allelopathic effect among the four chemical fractions. In summary, the results indicated that switchgrass has allelopathic potential; however, there is not enough evidence to conclude that allelopathic advantage is the main factor that has contributed to the successful establishment of switchgrass on China’s Loess Plateau.

  1. Genomics-Assisted Exploitation of Heterosis in Perennial Ryegrass (Lolium perenne L.)

    DEFF Research Database (Denmark)

    Islam, Md. Shofiqul

    ryegrass for the development of improved varieties. During his PhD studies, Mohammad Shofiqul Islam studied the feasibility of developing novel hybrid breeding schemes based on cytoplasmic male sterility (CMS) systems in perennial ryegrass. He successfully completed the assembly and annotation of a male......-fertile perennial ryegrass mitochondrial genome, and identified candidate genes responsible for the CMS phenotype by comparing male-fertile and male-sterile mitochondrial genomes. His findings constitute a good basis for continuing research to produce hybrid grass varieties to address the future needs......, breeding activities have been carried out to improve the population and develop synthetic varieties. This does not fully exploit the potential of heterosis, however. Hybrid breeding is an alternative strategy and provides opportunities to fully exploit the genetically available heterosis in perennial...

  2. Establishment techniques in under-sown perennial ryegrass for seed production

    DEFF Research Database (Denmark)

    Deleuran, Lise C; Boelt, Birte

    2009-01-01

    Establishment methods have proven to be of major importance for grass-seed production. The objective of this research was to test the effect of different sowing techniques on plant establishment and the subsequent seed yield. Perennial ryegrass (Lolium perenne L.) is used as the model grass due...... to its large importance in Danish agriculture. In a three-year trial six different methods of under-sowing of perennial ryegrass in a spring barley cover crop were employed. Perennial ryegrass was either sown directly at different depths within the spring barley (Hordeum vulgare L.) rows or placed 2, 6......, or 12 cm from the spring barley rows. Results of dry-matter yield indicate that the best establishment of the grass occurred when placing the grass 6 or 12 cm from the cover-crop row, and this is of importance in less vigorous grasses. Overall, no seed-yield difference has been observed for perennial...

  3. Herbicide Safeners Decrease Sensitivity to Herbicides Inhibiting Acetolactate-Synthase and Likely Activate Non-Target-Site-Based Resistance Pathways in the Major Grass Weed Lolium sp. (Rye-Grass

    Directory of Open Access Journals (Sweden)

    Arnaud Duhoux

    2017-08-01

    Full Text Available Herbicides are currently pivotal to control weeds and sustain food security. Herbicides must efficiently kill weeds while being as harmless as possible for crops, even crops taxonomically close to weeds. To increase their selectivity toward crops, some herbicides are sprayed in association with safeners that are bioactive compounds exacerbating herbicide-degrading pathways reputedly specifically in crops. However, exacerbated herbicide metabolism is also a key mechanism underlying evolved non-target-site-based resistance to herbicides (NTSR in weeds. This raised the issue of a possible role of safeners on NTSR evolution in weeds. We investigated a possible effect of the respective field rates of the two broadly used safeners cloquintocet-mexyl and mefenpyr-diethyl on the sensitivity of the troublesome global weed Lolium sp. (rye-grass to the major herbicides inhibiting acetolactate-synthase (ALS pyroxsulam and iodosulfuron + mesosulfuron, respectively. Three Lolium sp. populations were studied in three series of experiments. The first experiment series compared the frequencies of plants surviving application of each herbicide alone or in association with its safener. Safener co-application caused a net increase ranging from 5.0 to 46.5% in the frequency of plants surviving the field rate of their associated herbicide. In a second series of experiments, safener effect was assessed on individual plant sensitivity using vegetative propagation. A reduction in sensitivity to pyroxsulam and to iodosulfuron + mesosulfuron was observed for 44.4 and 11.1% of the plants in co-treatment with cloquintocet-mexyl and mefenpyr-diethyl, respectively. A third series of experiments investigated safener effect on the expression level of 19 Lolium sp. NTSR marker genes. Safeners showed an enhancing effect on the expression level of 10 genes. Overall, we demonstrated that cloquintocet-mexyl and mefenpyr-diethyl both reduced the sensitivity of Lolium sp. to their

  4. Herbicide Safeners Decrease Sensitivity to Herbicides Inhibiting Acetolactate-Synthase and Likely Activate Non-Target-Site-Based Resistance Pathways in the Major Grass Weed Lolium sp. (Rye-Grass).

    Science.gov (United States)

    Duhoux, Arnaud; Pernin, Fanny; Desserre, Diane; Délye, Christophe

    2017-01-01

    Herbicides are currently pivotal to control weeds and sustain food security. Herbicides must efficiently kill weeds while being as harmless as possible for crops, even crops taxonomically close to weeds. To increase their selectivity toward crops, some herbicides are sprayed in association with safeners that are bioactive compounds exacerbating herbicide-degrading pathways reputedly specifically in crops. However, exacerbated herbicide metabolism is also a key mechanism underlying evolved non-target-site-based resistance to herbicides (NTSR) in weeds. This raised the issue of a possible role of safeners on NTSR evolution in weeds. We investigated a possible effect of the respective field rates of the two broadly used safeners cloquintocet-mexyl and mefenpyr-diethyl on the sensitivity of the troublesome global weed Lolium sp. (rye-grass) to the major herbicides inhibiting acetolactate-synthase (ALS) pyroxsulam and iodosulfuron + mesosulfuron, respectively. Three Lolium sp. populations were studied in three series of experiments. The first experiment series compared the frequencies of plants surviving application of each herbicide alone or in association with its safener. Safener co-application caused a net increase ranging from 5.0 to 46.5% in the frequency of plants surviving the field rate of their associated herbicide. In a second series of experiments, safener effect was assessed on individual plant sensitivity using vegetative propagation. A reduction in sensitivity to pyroxsulam and to iodosulfuron + mesosulfuron was observed for 44.4 and 11.1% of the plants in co-treatment with cloquintocet-mexyl and mefenpyr-diethyl, respectively. A third series of experiments investigated safener effect on the expression level of 19 Lolium sp. NTSR marker genes. Safeners showed an enhancing effect on the expression level of 10 genes. Overall, we demonstrated that cloquintocet-mexyl and mefenpyr-diethyl both reduced the sensitivity of Lolium sp. to their associated ALS

  5. Genetic linkage mapping in an F2 perennial ryegrass population using DArT markers

    DEFF Research Database (Denmark)

    Tomaszewski, Céline; Byrne, Stephen; Foito, Alexandra

    2012-01-01

    Perennial ryegrass is the principal forage grass species used in temperate agriculture. In recent years, significant efforts have been made to develop molecular marker strategies to allow cost-effective characterization of a large number of loci simultaneously. One such strategy involves using DAr......T markers, and a DArT array has recently been developed for the Lolium-Festuca complex. In this study, we report the first use of the DArTFest array to generate a genetic linkage map based on 326 markers in a Lolium perenne F2 population, consisting of 325 genotypes. For proof of concept, the map was used...

  6. Effects of chicory/perennial ryegrass swards compared with perennial ryegrass swards on the performance and carcass quality of grazing beef steers.

    Directory of Open Access Journals (Sweden)

    Christina L Marley

    Full Text Available An experiment investigated whether the inclusion of chicory (Cichorium intybus in swards grazed by beef steers altered their performance, carcass characteristics or parasitism when compared to steers grazing perennial ryegrass (Lolium perenne. Triplicate 2-ha plots were established with a chicory/ryegrass mix or ryegrass control. Forty-eight Belgian Blue-cross steers were used in the first grazing season and a core group (n = 36 were retained for finishing in the second grazing season. The experiment comprised of a standardisation and measurement period. During standardisation, steers grazed a ryegrass/white clover pasture as one group. Animals were allocated to treatment on the basis of liveweight, body condition and faecal egg counts (FEC determined 7 days prior to the measurement period. The measurement period ran from 25 May until 28 September 2010 and 12 April until 11 October 2011 in the first and second grazing year. Steers were weighed every 14 days at pasture or 28 days during housing. In the first grazing year, faecal samples were collected for FEC and parasite cultures. At the end of the first grazing year, individual blood samples were taken to determine O. ostertagi antibody and plasma pepsinogen levels. During winter, animals were housed as one group and fed silage. In the second grazing year, steers were slaughtered when deemed to reach fat class 3. Data on steer performance showed no differences in daily live-weight gain which averaged 1.04 kg/day. The conformation, fat grade and killing out proportion of beef steers grazing chicory/ryegrass or ryegrass were not found to differ. No differences in FEC, O. ostertagi antibody or plasma pepsinogen levels of beef steers grazing either chicory/ryegrass or ryegrass were observed. Overall, there were no detrimental effects of including chicory in swards grazed by beef cattle on their performance, carcass characteristics or helminth parasitism, when compared with steers grazing ryegrass.

  7. Genetic markers for flowering in perennial ryegrass

    DEFF Research Database (Denmark)

    Paina, Cristiana; Byrne, Stephen; Andersen, Jeppe Reitan

    2011-01-01

    Perennial ryegrass (Lolium perenne L.) is the principal forage grass utilized in Danish agriculture and underpins the beef and dairy sectors. It is characterized as having high digestibility, high nutritional value, and high productivity during vegetative growth. However, at the reproductive growth...... genes will be converted to molecular markers and mapped in an existing mapping population previously characterized for flowering time and vernalization response. References: Amasino, R.M., Michaels S.D. (2010). The Timing of Flowering. Plant Physiology 154: 516–520 Greenup, A., W. Peacock, W.J., Dennis...

  8. Population structure, genetic variation and linkage disequilibrium in perennial ryegrass populations divergently selected for freezing tolerance

    Directory of Open Access Journals (Sweden)

    Mallikarjuna Rao eKovi

    2015-11-01

    Full Text Available Low temperature is one of the abiotic stresses seriously affecting the growth of perennial ryegrass (Lolium perenne L. Understanding the genetic control of freezing tolerance would aid in the development of cultivars of perennial ryegrass with improved adaptation to frost. A total number of 80 individuals (24 of High frost [HF]; 29 of Low frost [LF] and 27 of Unselected [US] from the second generation of the two divergently selected populations and an unselected control population were genotyped using 278 genome-wide SNPs derived from Lolium perenne L. transcriptome sequence. Our studies showed that the HF and LF populations are very divergent after selection for freezing tolerance, whereas the HF and US populations are more similar. Linkage disequilibrium (LD decay varied across the seven chromosomes and the conspicuous pattern of LD between the HF and LF population confirmed their divergence in freezing tolerance. Furthermore, two Fst outlier methods; finite island model (fdist by LOSITAN and hierarchical structure model using ARLEQUIN detected six loci under directional selection. These outlier loci are most probably linked to genes involved in freezing tolerance, cold adaptation and abiotic stress and might be the potential marker resources for breeding perennial ryegrass cultivars with improved freezing tolerance.

  9. Transpiration efficiency of three Mediterranean annual pasture species and wheat.

    Science.gov (United States)

    Bolger, T P; Turner, N C

    1998-06-01

    Attempts to improve water use efficiency in regions with Mediterranean climates generally focus on increasing plant transpiration relative to evaporation from the soil and increasing transpiration efficiency. Our aim was to determine if transpiration efficiency differs among key species occurring in annual pastures in southern Australia. Two glasshouse experiments were conducted with three key pasture species, subterranean clover (Trifolium subterraneum L.), capeweed [Arctotheca calendula (L.) Levyns] and annual ryegrass (Lolium rigidum Gaudin), and wheat (Triticum aestivum L.). Transpiration efficiency was assessed at the levels of␣whole-plant biomass and water use (W), leaf gas exchange measurements of the ratio of CO 2 assimilation to leaf conductance to water vapour (A/g), and carbon isotope discrimination (Δ) in leaf tissue. In addition, Δ was measured on shoots of the three pasture species growing together in the field. In the glasshouse studies, annual ryegrass had a consistently higher transpiration efficiency than subterranean clover or capeweed by all methods of measurement. Subterranean clover and capeweed had similar transpiration efficiencies by all three methods of measurement. Wheat had W values similar to ryegrass but A/g and Δ values similar to subterranean clover or capeweed. The high W of annual ryegrass seems to be related to a conservative leaf gas exchange behaviour, with lower assimilation and conductance but higher A/g than for the other species. In contrast to the glasshouse results, the three pasture species had similar Δ values when growing together in mixed-species swards in the field. Reasons for these differing responses between glasshouse and field-grown plants are discussed in terms of the implications for improving the transpiration efficiency of mixed-species annual pasture communities in the field.

  10. In-vitro assessment of the probiotic potential of Lactobacillus plantarum KCC-24 isolated from Italian rye-grass (Lolium multiflorum) forage.

    Science.gov (United States)

    Vijayakumar, Mayakrishnan; Ilavenil, Soundharrajan; Kim, Da Hye; Arasu, Mariadhas Valan; Priya, Kannappan; Choi, Ki Choon

    2015-04-01

    The aim of the present study was to determine the probiotic potential of the lactic acid bacteria Lactobacillus plantarum KCC-24 (L. plantarum KCC-24), that was isolated and characterized from Italian ryegrass (Lolium multiflorum) forage. The following experiments were performed to assess the probiotic characteristics such as antifungal activity, antibiotic susceptibility, resistance to low pH, stimulated gastric juice and bile salts, proteolytic activity, auto-aggregation, cell surface hydrophobicity, and in vitro antioxidant property. The isolated L. plantarum KCC-24 exhibited significant antifungal activity against the various fungal strains of Aspergillus fumigatus (73.43%), Penicillium chrysogenum (59.04%), Penicillium roqueforti (56.67%), Botrytis elliptica (40.23%), Fusarium oxysporum (52.47%) and it was susceptible to numerous antibiotics, survived in low pH, was resistant to stimulated gastric juices and bile salts (0.3% w/v). Moreover, L. plantarum KCC-24 exhibited good proteolytic activity. In addition L. plantarum KCC-24 showed potent antioxidant and hydrogen peroxide resistant property. In conclusion, the isolated L. plantarum KCC-24 exhibited several characteristics to prove it's excellent as a potential probiotic candidate for developing quality food for ruminant animals and human. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Depletion of carbohydrate reserves limits nitrate uptake during early regrowth in Lolium perenne L.

    Czech Academy of Sciences Publication Activity Database

    Guo, Q.; Turnbull, M.; Song, J.; Roche, J.; Novák, Ondřej; Späth, J.; Jameson, P. E.; Love, J.

    2017-01-01

    Roč. 68, č. 7 (2017), s. 1569-1583 ISSN 0022-0957 R&D Projects: GA ČR(CZ) GA17-06613S Institutional support: RVO:61389030 Keywords : Carbohydrate * Carbon * Cytokinin * Fructan * Lolium perenne * Nitrate transporter (NRT) * Nitrate uptake * Nitrogen * Nitrogen use efficiency (NUE) * Perennial ryegrass Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 5.830, year: 2016

  12. Path and correlation analysis of perennial ryegrass (Lolium perenne L.) seed yield components

    DEFF Research Database (Denmark)

    Abel, Simon; Gislum, René; Boelt, Birte

    2017-01-01

    Maximum perennial ryegrass seed production potential is substantially greater than harvested yields with harvested yields representing only 20% of calculated potential. Similar to wheat, maize and other agriculturally important crops, seed yield is highly dependent on a number of interacting seed...... yield components. This research was performed to apply and describe path analysis of perennial ryegrass seed yield components in relation to harvested seed yields. Utilising extensive yield components which included subdividing reproductive inflorescences into five size categories, path analysis...... was undertaken assuming a unidirectional causal-admissible relationship between seed yield components and harvested seed yield in six commercial seed production fields. Both spikelets per inflorescence and florets per spikelet had a significant (p seed yield; however, total...

  13. Delayed chlorophyll a fluorescence, MR 820, and gas exchange changes in perennial ryegrass under salt stress

    Energy Technology Data Exchange (ETDEWEB)

    Dąbrowski, P., E-mail: piotr_dabrowski@sggw.pl [Department of Environmental Improvement, Warsaw University of Life Sciences-SGGW, 159 Nowoursynowska St., 02-776 Warsaw (Poland); Kalaji, M.H., E-mail: hazem@kalaji.pl [Department of Plant Physiology, Warsaw University of Life Sciences-SGGW, 159 Nowoursynowska St., 02-776 Warsaw (Poland); SI TECHNOLOGY Sp. z o. o., Górczewska 226C/26, 01-460 Warsaw (Poland); Baczewska, A.H., E-mail: a.baczewska@obpan.pl [Polish Academy of Sciences Botanical Garden-Center for Biological Diversity Conservation in Powsin, 2 Prawdziwka St., 02-973 Warsaw (Poland); Pawluśkiewicz, B. [Department of Environmental Improvement, Warsaw University of Life Sciences-SGGW, 159 Nowoursynowska St., 02-776 Warsaw (Poland); Mastalerczuk, G., E-mail: grazyna_mastalerczuk@sggw.pl [Department of Agronomy, Warsaw University of Life Sciences-SGGW, 159 Nowoursynowska St., 02-776 Warsaw (Poland); Borawska-Jarmułowicz, B., E-mail: barbara_borawska_jarmulowicz@sggw.pl [Department of Agronomy, Warsaw University of Life Sciences-SGGW, 159 Nowoursynowska St., 02-776 Warsaw (Poland); Paunov, M. [Department Biophysics and Radiobiology, St. Kl. Ohridski Sofia University, 8 Dragan Tsankov Blvd., 1164 Sofia (Bulgaria); Goltsev, V., E-mail: goltsev@biofac.uni-sofia.bg [Department Biophysics and Radiobiology, St. Kl. Ohridski Sofia University, 8 Dragan Tsankov Blvd., 1164 Sofia (Bulgaria)

    2017-03-15

    Perennial ryegrass (Lolium perenne L.) is one of the more popular grass species in Europe. It is commonly used for starting lawns in urban areas, where plant growth is limited by many environmental conditions. The contamination of soils by salt is one of the major problems in urban green areas, as well as in natural areas. The basic aim of this study is to provide a detailed in vivo analysis of the changes in the delayed chlorophyll fluorescence and MR 820 signals (induced by salt stress) of two lawn varieties of perennial ryegrass, and to find out if there are correlations between these parameters and gas exchange. Two lawn varieties of Lolium perenne L. were used: Nira and Roadrunner. Salinization was performed at 8 weeks after sowing by adding NaCl in water solution (0, 0.15, and 0.30 M). There were 8 terms of measurement: 0 h, 24 h, 48 h, 96 h, 144 h, 192 h, 240 h, and 288 h after salinization. Our results showed that delayed fluorescence is a tool that can bring completely new opportunities for detecting stress in plants caused by salt. Our work allowed us to identify various limitation patterns in the photosynthetic efficiency of perennial ryegrass lawn varieties grown under salt stress conditions. Significant differences between the two tested varieties in response to salt stress were confirmed.

  14. Delayed chlorophyll a fluorescence, MR 820, and gas exchange changes in perennial ryegrass under salt stress

    International Nuclear Information System (INIS)

    Dąbrowski, P.; Kalaji, M.H.; Baczewska, A.H.; Pawluśkiewicz, B.; Mastalerczuk, G.; Borawska-Jarmułowicz, B.; Paunov, M.; Goltsev, V.

    2017-01-01

    Perennial ryegrass (Lolium perenne L.) is one of the more popular grass species in Europe. It is commonly used for starting lawns in urban areas, where plant growth is limited by many environmental conditions. The contamination of soils by salt is one of the major problems in urban green areas, as well as in natural areas. The basic aim of this study is to provide a detailed in vivo analysis of the changes in the delayed chlorophyll fluorescence and MR 820 signals (induced by salt stress) of two lawn varieties of perennial ryegrass, and to find out if there are correlations between these parameters and gas exchange. Two lawn varieties of Lolium perenne L. were used: Nira and Roadrunner. Salinization was performed at 8 weeks after sowing by adding NaCl in water solution (0, 0.15, and 0.30 M). There were 8 terms of measurement: 0 h, 24 h, 48 h, 96 h, 144 h, 192 h, 240 h, and 288 h after salinization. Our results showed that delayed fluorescence is a tool that can bring completely new opportunities for detecting stress in plants caused by salt. Our work allowed us to identify various limitation patterns in the photosynthetic efficiency of perennial ryegrass lawn varieties grown under salt stress conditions. Significant differences between the two tested varieties in response to salt stress were confirmed.

  15. Evaluación agronómica y nutricional del pasto Ryegrass perenne tetraploide (Lolium perenne producido en lecherías de las zonas altas de Costa Rica. II. Valor nutricional

    Directory of Open Access Journals (Sweden)

    Luis Villalobos

    2010-01-01

    Full Text Available Se determinó el valor nutricional del pasto ryegrass perenne tetraploide (Lolium perenne en 4 fincas comerciales de ganado lechero ubicadas en Chicuá de Oreamuno (latitud 09°59', longitud 83°52', altitud 3090 msnm, provincia de Cartago. Las muestras se tomaron cada 2 meses a una altura de cosecha de 10 cm sobre el suelo, simulando el pastoreo que realizan los animales durante un período de un año. La composición nutricional promedio anual fue de 25,21% PC, 46,26% FDN, 25,57% FDA, 3,29% lignina, 15,40% CNF y 77,95% DIVMS y su contenido energético, expresado como TND, ED, EM, ENL (3X y ENG, fue 61,95%, 2,92, 2,45, 1,53 y 0,92 Mcal.kg-1 de MS, respectivamente. El valor nutricional del pasto ryegrass perenne varió (p¿0,05 según la época del año y el manejo en finca, especialmente en lo referente al período de recuperación de las pasturas. Este pasto tiene un contenido alto de PC y CNF, que permite a nivel ruminal la producción de proteína microbial, la cual es la mejor proteína que puede consumir un rumiante. En general, el valor nutricional del pasto Ryegrass perenne producido a altitudes superiores a los 2500 msnm en Costa Rica es similar, al producido en zonas de clima templado de donde es originario.

  16. Genetic structure of annual ryegrass (Lolium multiflorum populations estimated by RAPD Estrutura genética de populações de azevém anual (Lolium multiflorum estimada por RAPD

    Directory of Open Access Journals (Sweden)

    Eduardo Alano Vieira

    2004-01-01

    Full Text Available Annual ryegrass is a temperate climate annual foraging grass, grown mostly in the South of Brazil, especially in the state of Rio Grande do Sul. Despite its importance, little is known about its genetic diversity, both within and among the populations cultivated. This knowledge is of fundamental importance for developing breeding and conservation strategies. The aim of this study was to characterize the genetic diversity and structure of four populations of annual ryegrass. Three of the populations were located in Rio Grande do Sul and the fourth in Uruguay. RAPD markers were used to study the genetic diversity and structure of these populations. Analysis of 375 individuals sampled from the populations, using six RAPD primers, generated a total of 82 amplified bands. They included 73 polymorphic bands (89,02%. The value of the total genetic diversity index obtained, (0,71 was high, indicating the presence of wide genetic diversity in the four populations. Genetic structure analysis revealed that 98% of total diversity is intrapopulational, whereas interpopulational genetic diversity was only 2%. These results suggest that before these populations separated, they had gone through a period of gene exchange and, even after the separation event, gene frequency stayed at levels similar to the original levels, with no differential selection for these genes in the different cultivation areas.O azevém anual é a gramínea anual forrageira de clima temperado de maior utilização no sul do Brasil, particularmente no Estado do Rio Grande do Sul. Apesar de toda a importância que a espécie apresenta, pouco se conhece a respeito da diversidade genética presente entre e dentro das populações cultivadas. Este conhecimento é de fundamental importância para o estabelecimento das estratégias de melhoramento genético e de conservação destes materiais. O objetivo deste estudo foi caracterizar a diversidade genética e a estrutura genética de quatro

  17. Effect of sewage sludge and sawdust in association with hybrid ryegrass (Lolium x hybrydum Hausskin. on soil macroaggregates and water content Efectos de lodos urbanos y aserrín en asociación con ballica (Lolium x hybrydum Hausskn. sobre los microagregados y contenido de agua del suelo

    Directory of Open Access Journals (Sweden)

    Marco Sandoval E

    2012-12-01

    Full Text Available Chilean soils degradation is a serious problem affecting directly the productivity of most of the crops. Some evidence indicates sewage sludge can improve soil physical properties, especially when combined with sawdust. The objective of this work was to evaluate the effect of different mixtures of sewage sludge (LU and sawdust (RA on water-stable aggregates and available water content of a degraded Alfisol cropped with hybrid ryegrass (Lolium x hybridum Hausskn., under greenhouse conditions. The experimental design was a completely randomized with a factorial arrangement of 2 x 9 (ryegrass x rates of sludge and sawdust. Treatments were 25 and 50 Mg LU ha-1 mixed with 10, 25, and 50 Mg RA ha-1. Ratio mixtures of LU/RA were set in pots with hybrid ryegrass. Soil available water content (AW, percentage of macroaggregates (MA and water-stable aggregates (AWD were evaluated. Ryegrass aboveground biomass was also measured. Mixtures of LU/RA amended to the soil increased MA and AWD, an effect that was most evident at 50 Mg ha-1. The AW value was greater when LU was amended to 50 Mg ha-1 mixed with RA at doses of 10, 25, and 50 Mg ha-1. There was greater aboveground biomass of hybrid ryegrass, directly related to increasing doses of LU and RA in the mixtures. The addition to soil of both organic residues combined, LU and RA, improved the physical parameters studied, especially in the presence of hybrid ryegrass.La degradation de los suelos chilenos es un serio problema que afecta directamente la productividad de la mayoría de los cultivos. Los lodos urbanos pueden mejorar las propiedades físicas del suelo, sobre todo si van acompanadas con aserrín. El objetivo fue evaluar el efecto de distintas mezclas de lodo urbano (LU y aserrín (RA sobre los agregados estables al agua y el contenido de agua disponible en un Alfisol degradado y cultivado con ballica híbrida (Lolium x hybridum Hausskn., bajo invernadero. El diseno experimental fue completamente al

  18. Genetic variation, population structure, and linkage disequilibrium in European elite germplasm of perennial ryegrass

    DEFF Research Database (Denmark)

    Brazauskas, Gintaras; Lenk, Ingo; Pedersen, Morten Greve

    2011-01-01

    Perennial ryegrass (Lolium perenne L.) is a highly valued temperate climate grass species grown as forage crop and for amenity uses. Due to its outbreeding nature and recent domestication, a high degree of genetic diversity is expected among cultivars. The aim of this study was to assess the extent...... of linkage disequilibrium (LD) within European elite germplasm and to evaluate the appropriate methodology for genetic association mapping in perennial ryegrass. A high level of genetic diversity was observed in a set of 380 perennial ryegrass elite genotypes when genotyped with 40 SSRs and 2 STS markers...... and occurred within 0.4 cM across European varieties, when population structure was taken into consideration. However, an extended LD of up to 6.6 cM was detected within the variety Aberdart. High genetic diversity and rapid LD decay provide means for high resolution association mapping in elite materials...

  19. Effect of in situ soil amendments on arsenic uptake in successive harvests of ryegrass (Lolium perenne cv Elka) grown in amended As-polluted soils

    International Nuclear Information System (INIS)

    Hartley, William; Lepp, Nicholas W.

    2008-01-01

    Several iron-bearing additives, selected for their potential ability to adsorb anions, were evaluated for their effectiveness in attenuation of arsenic (As) in three soils with different sources of contamination. Amendments used were lime, goethite (α-FeOOH) (crystallised iron oxide) and three iron-bearing additives, iron grit, Fe II and Fe III sulphates plus lime, applied at 1% w/w. Sequential extraction schemes conducted on amended soils determined As, Cu, Zn and Ni fractionation. Plant growth trials using perennial ryegrass (Lolium perenne var. Elka) assessed shoot As uptake. This was grown in the contaminated soils for 4 months, during which time grass shoots were successively harvested every 3 weeks. Goethite increased biomass yields, but clear differences were observed in As transfer rates with the various iron oxides. In conclusion, whilst Fe-oxides may be effective in situ amendments, reducing As bioavailability, their effects on plant growth require careful consideration. Soil-plant transfer of As was not completely halted by any amendment. - Arsenic attenuation is illustrated using Fe-based amendments, their efficacy providing different indicators of success

  20. Understanding Lolium rigidum Seeds: The Key to Managing a Problem Weed?

    Directory of Open Access Journals (Sweden)

    Kathryn J. Steadman

    2012-09-01

    Full Text Available The 40 million hectare southern Australian winter cropping region suffers from widespread infestation by Lolium rigidum (commonly known as annual or rigid ryegrass, a Mediterranean species initially introduced as a pasture plant. Along with its high competitiveness within crops, rapid adaptability and widespread resistance to herbicides, the dormancy of its seeds means that L. rigidum is the primary weed in southern Australian agriculture. With the individuals within a L. rigidum population exhibiting varying levels of seed dormancy, germination can be staggered across the crop-growing season, making complete weed removal virtually impossible, and ensuring that the weed seed bank is constantly replenished. By understanding the processes involved in induction and release of dormancy in L. rigidum seeds, it may be possible to develop strategies to more effectively manage this pest without further stretching herbicide resources. This review examines L. rigidum seed dormancy and germination from a weed-management perspective and explains how the seed bank can be depleted by control strategies encompassing all stages in the lifecycle of a seed, from development to germination.

  1. Transcriptional Profiling and Identification of Heat-Responsive Genes in Perennial Ryegrass by RNA-Sequencing

    Directory of Open Access Journals (Sweden)

    Kehua Wang

    2017-06-01

    Full Text Available Perennial ryegrass (Lolium perenne is one of the most widely used forage and turf grasses in the world due to its desirable agronomic qualities. However, as a cool-season perennial grass species, high temperature is a major factor limiting its performance in warmer and transition regions. In this study, a de novo transcriptome was generated using a cDNA library constructed from perennial ryegrass leaves subjected to short-term heat stress treatment. Then the expression profiling and identification of perennial ryegrass heat response genes by digital gene expression analyses was performed. The goal of this work was to produce expression profiles of high temperature stress responsive genes in perennial ryegrass leaves and further identify the potentially important candidate genes with altered levels of transcript, such as those genes involved in transcriptional regulation, antioxidant responses, plant hormones and signal transduction, and cellular metabolism. The de novo assembly of perennial ryegrass transcriptome in this study obtained more total and annotated unigenes compared to previously published ones. Many DEGs identified were genes that are known to respond to heat stress in plants, including HSFs, HSPs, and antioxidant related genes. In the meanwhile, we also identified four gene candidates mainly involved in C4 carbon fixation, and one TOR gene. Their exact roles in plant heat stress response need to dissect further. This study would be important by providing the gene resources for improving heat stress tolerance in both perennial ryegrass and other cool-season perennial grass plants.

  2. Ergovaline does not alter the severity of ryegrass staggers induced by lolitrem B.

    Science.gov (United States)

    Finch, S C; Vlaming, J B; Sutherland, B L; van Koten, C; Mace, W J; Fletcher, L R

    2018-03-01

    To investigate a possible interaction between lolitrem B and ergovaline by comparing the incidence and severity of ryegrass staggers in sheep grazing ryegrass (Lolium perenne) containing lolitrem B or ryegrass containing both lolitrem B and ergovaline. Ninety lambs, aged approximately 6 months, were grazed on plots of perennial ryegrass infected with either AR98 endophyte (containing lolitrem B), standard endophyte (containing lolitrem B and ergovaline) or no endophyte, for up to 42 days from 2 February 2010. Ten lambs were grazed on three replicate plots per cultivar. Herbage samples were collected for alkaloid analysis and lambs were scored for ryegrass staggers (scores from 0-5) weekly during the study. Any animal which was scored ≥4 was removed from the study. Concentrations of lolitrem B did not differ between AR98 and standard endophyte-infected pastures during the study period (p=0.26), and ergovaline was present only in standard endophyte pastures. Ryegrass staggers was observed in sheep grazing both the AR98 and standard endophyte plots, with median scores increasing in the third week of the study. Prior to the end of the 42-day grazing period, 22 and 17 animals were removed from the standard endophyte and AR98 plots, respectively, because their staggers scores were ≥4. The cumulative probability of lambs having scores ≥4 did not differ between animals grazing the two pasture types (p=0.41). There was no evidence for ergovaline increasing the severity of ryegrass staggers induced by lolitrem B. In situations where the severity of ryegrass staggers appears to be greater than that predicted on the basis of concentrations of lolitrem B, the presence of other tremorgenic alkaloids should be investigated.

  3. Cytogenetics of Festulolium (Festuca x Lolium hybrids).

    Science.gov (United States)

    Kopecký, D; Lukaszewski, A J; Dolezel, J

    2008-01-01

    Grasses are the most important and widely cultivated crops. Among them, ryegrasses (Lolium spp.) and fescues (Festuca spp.) provide high quality fodder for livestock, are used for turf and amenity purposes, and play a fundamental role in environment protection. Species from the two genera display complementary agronomic characteristics and are often grown in mixtures. Breeding efforts to combine desired features in single entities culminated with the production of Festuca x Lolium hybrids. The so called Festuloliums enjoy a considerable commercial success with numerous cultivars registered all over the world. They are also very intriguing from a strictly cytogenetic point of view as the parental chromosomes recombine freely in hybrids. Until a decade ago this phenomenon was only known in general quantitative terms. The introduction of molecular cytogenetic tools such as FISH and GISH permitted detailed studies of intergeneric chromosome recombination and karyotyping of Festulolium cultivars. These tools were also invaluable in revealing the origin of polyploid fescues, and facilitated the development of chromosome substitution and introgression lines and physical mapping of traits of interest. Further progress in this area will require the development of a larger set of cytogenetic markers and high-resolution cytogenetic maps. It is expected that the Lolium-Festuca complex will continue providing opportunities for breeding superior grass cultivars and the complex will remain an attractive platform for fundamental research of the early steps of hybrid speciation and interaction of parental genomes, as well as the processes of chromosome pairing, elimination and recombination. 2008 S. Karger AG, Basel

  4. Nutrients can enhance the abundance and expression of alkane hydroxylase CYP153 gene in the rhizosphere of ryegrass planted in hydrocarbon-polluted soil.

    Directory of Open Access Journals (Sweden)

    Muhammad Arslan

    Full Text Available Plant-bacteria partnership is a promising strategy for the remediation of soil and water polluted with hydrocarbons. However, the limitation of major nutrients (N, P and K in soil affects the survival and metabolic activity of plant associated bacteria. The objective of this study was to explore the effects of nutrients on survival and metabolic activity of an alkane degrading rhizo-bacterium. Annual ryegrass (Lolium multiflorum was grown in diesel-contaminated soil and inoculated with an alkane degrading bacterium, Pantoea sp. strain BTRH79, in greenhouse experiments. Two levels of nutrients were applied and plant growth, hydrocarbon removal, and gene abundance and expression were determined after 100 days of sowing of ryegrass. Results obtained from these experiments showed that the bacterial inoculation improved plant growth and hydrocarbon degradation and these were further enhanced by nutrients application. Maximum plant biomass production and hydrocarbon mineralization was observed by the combined use of inoculum and higher level of nutrients. The presence of nutrients in soil enhanced the colonization and metabolic activity of the inoculated bacterium in the rhizosphere. The abundance and expression of CYP153 gene in the rhizosphere of ryegrass was found to be directly associated with the level of applied nutrients. Enhanced hydrocarbon degradation was associated with the population of the inoculum bacterium, the abundance and expression of CYP153 gene in the rhizosphere of ryegrass. It is thus concluded that the combination between vegetation, inoculation with pollutant-degrading bacteria and nutrients amendment was an efficient approach to reduce hydrocarbon contamination.

  5. Nutrients Can Enhance the Abundance and Expression of Alkane Hydroxylase CYP153 Gene in the Rhizosphere of Ryegrass Planted in Hydrocarbon-Polluted Soil

    Science.gov (United States)

    Arslan, Muhammad; Afzal, Muhammad; Amin, Imran; Iqbal, Samina; Khan, Qaiser M.

    2014-01-01

    Plant-bacteria partnership is a promising strategy for the remediation of soil and water polluted with hydrocarbons. However, the limitation of major nutrients (N, P and K) in soil affects the survival and metabolic activity of plant associated bacteria. The objective of this study was to explore the effects of nutrients on survival and metabolic activity of an alkane degrading rhizo-bacterium. Annual ryegrass (Lolium multiflorum) was grown in diesel-contaminated soil and inoculated with an alkane degrading bacterium, Pantoea sp. strain BTRH79, in greenhouse experiments. Two levels of nutrients were applied and plant growth, hydrocarbon removal, and gene abundance and expression were determined after 100 days of sowing of ryegrass. Results obtained from these experiments showed that the bacterial inoculation improved plant growth and hydrocarbon degradation and these were further enhanced by nutrients application. Maximum plant biomass production and hydrocarbon mineralization was observed by the combined use of inoculum and higher level of nutrients. The presence of nutrients in soil enhanced the colonization and metabolic activity of the inoculated bacterium in the rhizosphere. The abundance and expression of CYP153 gene in the rhizosphere of ryegrass was found to be directly associated with the level of applied nutrients. Enhanced hydrocarbon degradation was associated with the population of the inoculum bacterium, the abundance and expression of CYP153 gene in the rhizosphere of ryegrass. It is thus concluded that the combination between vegetation, inoculation with pollutant-degrading bacteria and nutrients amendment was an efficient approach to reduce hydrocarbon contamination. PMID:25360680

  6. Fructan metabolism and changes in fructan composition during cold acclimation in perennial ryegrass

    DEFF Research Database (Denmark)

    Abeynayake, Shamila; Etzerodt, Thomas; Jonavičienė, Kristina

    2015-01-01

    . The ecotype ‘Falster’, adapted to cold climates, increased total fructan content and produced more fructans (DP˃7) in the roots than the variety ‘Veyo’, adapted to warmer climates suggesting that accumulation of fructans in roots, especially the high-DP fructans as an adaptive trait for plant recovery after......Perennial ryegrass (Lolium perenne L.) produces high levels of fructans as a mixture of oligomers with different degrees of polymerization (DP). The present study describes the analysis of the compositional changes in the full spectrum of fructan oligomers, fructan distribution between above ground...... biomass (top) and the roots, and the transcription of candidate genes involved in fructan metabolism during cold acclimation in perennial ryegrass variety ‘Veyo’ and ecotype ‘Falster’ from distinct geographical origins. We observed changes in fructan composition and induction of low-DP fructans...

  7. Nitrogen and Winter Cover Crop Effects on Spring and Summer Nutrient Uptake

    Science.gov (United States)

    Fertilization of bermudagrass [Cynodon dactylon (L.) Pers.] with swine-lagoon effluent in summer, April to September, does not match the period of productivity of the winter annual cover crops, annual ryegrass (Lolium multiflorum L.), cereal rye (Secale cereale), and berseem clover (Trifolium alexan...

  8. Dinitrogen fixation in white clover grown in pure stand and mixture with ryegrass estimated by the immobilized 15N isotope dilution method

    DEFF Research Database (Denmark)

    Jørgensen, F.V.; Jensen, E.S.; Schjørring, J.K.

    1999-01-01

    Dinitrogen fixation in white clover (Trifolium repens L.) grown in pure stand and mixture with perennial ryegrass (Lolium perenne L.) was determined in the field using N-15 isotope dilution and harvest of the shoots. The apparent transfer of clover N to perennial ryegrass was simultaneously...... assessed. The soil was labelled either by immobilizing N-15 in organic matter prior to establishment of the sward or by using the conventional labelling procedure in which N-15 fertilizer is added after sward establishment. Immobilization of N-15 in the soil organic matter has not previously been used...

  9. Allergenic fragments of ryegrass (Lolium perenne) pollen allergen Lol p IV.

    Science.gov (United States)

    Jaggi, K S; Ekramoddoullah, A K; Kisil, F T

    1989-01-01

    To facilitate studies on establishing the nature of structure/function relationships of allergens, ryegrass pollen allergen, Lol p IV, was cleaved into smaller fragments by cyanogen bromide (CNBr) and the resulting peptides were further digested with trypsin. The resulting peptides were then fractionated by high performance liquid chromatography (HPLC) on a C-18 reverse phase column. The allergenic activity of the HPLC fractions was evaluated in terms of their ability to inhibit the binding of 125I-Lol p IV to serum IgE antibodies of a grass-allergic patient. Many of these fractions inhibited the binding between the native allergen and IgE antibodies in a dose-dependent manner. The inhibitions were specific, i.e., the fractions did not inhibit the binding between 125I-Lol p I (a group-I ryegrass pollen allergen) and the IgE antibodies present in the allergic human serum. The possibility that the allergenic peptide fractions were contaminated by the native undegraded allergen, which might have accounted for the observed inhibition, was ruled out by the fact that the native allergen could not be detected by SDS-PAGE and the elution profiles of allergenically active peptides did not coincide with that of native allergen. One of the allergenic sites recognized by monoclonal antibody (Mab) 90, i.e., site A, was located in HPLC fractions 90-100 while another allergenic site B (recognized by Mab 12) appeared to be lost following the sequential digestion of Lol p IV with CNBr and trypsin.

  10. B chromosomes are associated with redistribution of genetic recombination towards lower recombination chromosomal regions in perennial ryegrass.

    Science.gov (United States)

    Harper, John; Phillips, Dylan; Thomas, Ann; Gasior, Dagmara; Evans, Caron; Powell, Wayne; King, Julie; King, Ian; Jenkins, Glyn; Armstead, Ian

    2018-04-09

    Supernumerary 'B' chromosomes are non-essential components of the genome present in a range of plant and animal species-including many grasses. Within diploid and polyploid ryegrass and fescue species, including the forage grass perennial ryegrass (Lolium perenne L.), the presence of B chromosomes has been reported as influencing both chromosome pairing and chiasma frequencies. In this study, the effects of the presence/absence of B chromosomes on genetic recombination has been investigated through generating DArT (Diversity Arrays Technology) marker genetic maps for six perennial ryegrass diploid populations, the pollen parents of which contained either two B or zero B chromosomes. Through genetic and cytological analyses of these progeny and their parents, we have identified that, while overall cytological estimates of chiasma frequencies were significantly lower in pollen mother cells with two B chromosomes as compared with zero B chromosomes, the recombination frequencies within some marker intervals were actually increased, particularly for marker intervals in lower recombination regions of chromosomes, namely pericentromeric regions. Thus, in perennial ryegrass, the presence of two B chromosomes redistributed patterns of meiotic recombination in pollen mother cells in ways which could increase the range of allelic variation available to plant breeders.

  11. Impact of no-till cover cropping of Italian ryegrass on above and below ground faunal communities inhabiting a soybean field with special emphasis on soybean cyst nematodes

    Science.gov (United States)

    Two field trials were conducted in Maryland to evaluate the ability of an Italian ryegrass (IR) (Lolium multiflorum) cover crop in a no-till soybean (Glycine max) planting to 1) reduce populations of plant-parasitic nematodes (i.e., the soybean cyst nematode, Heterodera glycines and lesion nematodes...

  12. Preliminary studies on allelopatic effect of some woody plants on seed germination of rye-grass and tall fescue.

    Science.gov (United States)

    Arouiee, H; Nazdar, T; Mousavi, A

    2010-11-01

    In order to investigation of allelopathic effects of some ornamental trees on seed germination of rye-grass (Lolium prenne) and tall fescue (Festuca arundinaceae), this experiment was conducted in a randomized complete block design with 3 replicates at the laboratory of Horticultural Sciences Department of Ferdowsi University of Mashhad, during 2008. In this research, we studied the effect of aqueous and hydro-alcoholic extracts of Afghanistan pine (Pinus eldarica), arizona cypress (Cupressus arizonica), black locust (Robinia psedue acacia) and box elder (Acer negundo) leaves that prepared in 1:5 ratio on seed germination percent and rate for two grasses. The results showed that all extracts decreased statistically seed germination in compared to control treatment. The highest germination percentage and germination rate of tested grass detected in control treatment. Hydro-alcoholic extracts of all woody plants (15, 30%) were completely inhibited seed germination of rye-grass and tall fescue. Also aqueous extract of arizona cypress was completely inhibited seed germination of tall fescue and had more inhibitory activity than other aqueous extracts on rye-grass. Between aqueous extracts, the highest and lowest seed germination of rye-grass was found in Afghanistan pine and arizona cypress, respectively.

  13. Photoperiodic regulation of flowering in perennial ryegrass involving a CONSTANS-like homolog

    DEFF Research Database (Denmark)

    Martin, J.; Storgaard, M.; Andersen, C.H.

    2004-01-01

    Photoperiod and vernalization are the two key environmental factors of the. oral induction of perennial ryegrass (Lolium perenne L.). Transition from vegetative to reproductive growth will only occur after an extended vernalization period, followed by an increase in day length and temperature. Here...... we report on the isolation and characterization of a L. perenne gene (LpCO) that is homologous to CONSTANS, and which is tightly coupled to the. oral inductive long day signal. Like other monocot CO-like proteins, the LpCO contains a zinc finger domain with a non-conserved B-Box2. Although the B-Box2...

  14. Nitrogen application in amenity-types of Lolium perenne L. grown for seed production

    DEFF Research Database (Denmark)

    Deleuran, Lise Christina; Boelt, Birte

    1998-01-01

    Three amenity-type perennial ryegrass (Lolium perenne) cultivars Elka, Taya and Pippin were undersown in 1991-93 in spring barley at Roskilde and Rnhave, Denmark, and given 0, 30 or 60 kg N ha-1 in autumn combined with 70, 100 or 130 kg N ha-1 in spring. Seed yield did not differ among cultiva......, and total seed yield was therefore not affected. The one exception was in 1991 when at one location dry matter production in autumn was low, and autumn N application resulted in increased N content, fertile tiller number and seed yield...

  15. Concentrate supplementation strategies in ryegrass pasture for productive performance in lambs

    International Nuclear Information System (INIS)

    Santos, S.K.; Falbo, M.K.; Sandini, I.E.; Pacentchuk, F.; Neumann, M.; Garbossa, G.

    2018-01-01

    This study evaluated the effect of two concentrate supplementation strategies on performance, metabolic profile and economic evaluation of suckling lambs and ewes in ryegrass (Lolium multiflorum) pasture. Twenty-seven ewes and 45 lambs were divided into three groups: (1) ryegrass pasture without supplementation - control (CON); (2) CON plus supplemented ewes and lambs at 1% of live weight (SEL), and (3) CON plus creep feeding supplemented lambs at 1% of live weight (CSL). Concentrate use increased (p<0.05) average daily gain (ADG) by 19.95% over CON (21.6 and 18.3% for SEL and CSL, respectively). Concentrate use contributed to minimizing forage quality fluctuation and provided greater ADG stability, mainly when ryegrass nutritional content and digestibility decreased. Blood metabolites profiles did not differ between groups, with exception of phosphorus which was higher for CON than SEL, and calcium which was higher for CSL than CON (p<0.05). Compared to CON, stoking rate values were greater to SEL (p<0.05). Compared to CSL, ewe and total stocking rate were greater (p<0.05) to SEL. Considering the control group as break even feed investment, SEL strategy had a positive economic return, while CSL showed economic losses. Concentrate use increased ADG of lambs and decrease the impact of nutrient quality changes of forage on daily gains, but must be considered that supplemental strategy used could affect negatively economic return.

  16. Medium-term response of microbial community to rhizodeposits of white clover and ryegrass and tracing of active processes induced by 13C and 15N labelled exudates

    DEFF Research Database (Denmark)

    Kusliene, Gedrime; Rasmussen, Jim; Kuzyakov, Yakov

    2014-01-01

    and actinomycetes was unaffected by plant species, but pool of Gram-negative and Gram-positive bacteria was greater under white clover at the 10 percent significance level. In the short term, microorganisms more actively utilised fresh exudates (13C-labelled) of ryegrass than of white clover. We expected ryegrass...... microbial groups in soil under white clover (Trifolium repens L.) and ryegrass (Lolium perenne L.) following leaf-labelling with 13C-bicarbonate and 15N-urea. In this way microbial N and 15N and the composition of PLFAs reflect the medium-term (two months) response of microorganisms to rhizodeposits......, whereas the 13C-label of the PLFAs reflects the short-term (one week) utilisation of root exudates following labelling of shoots. In the medium term, microbial biomass N and 15N were greater under the ryegrass, whereas total PLFA was higher under white clover. The relative abundance of fungi...

  17. Testing water-soluble carbohydrate QTL effects in perennial ryegrass (Lolium perenne L.) by marker selection

    NARCIS (Netherlands)

    Turner, L.B.; Farrell, M.; Humphreys, M.O.; Dolstra, O.

    2010-01-01

    Water-soluble carbohydrates (WSC) are an important factor determining the nutritional value of grass forage and development of genetic markers for selection of WSC traits in perennial ryegrass would benefit future breeding programmes. Quantitative trait loci (QTLs) for WSC have been published for an

  18. Comportamento agronômico de populações de azevém anual (Lolium multiflorum L. para cultivo invernal na região sudeste Agronomic behaviour of annual ryegrass (Lolium multiflorum L. populations for winter cropping in Southeast Region of Brazil

    Directory of Open Access Journals (Sweden)

    Antonio Vander Pereira

    2008-04-01

    Full Text Available Na Região Sudeste o período do inverno é caracterizado pela escassez e perda de qualidade das pastagens, sendo o azevém anual uma das forrageiras invernais mais recomendadas para suplementação da dieta dos rebanhos leiteiros nesta época do ano. Com este trabalho, buscou-se avaliar o comportamento de populações de azevém resultantes de coleta de germoplasma. Foram avaliadas 30 populações, sendo 22 resultantes de coletas recentes realizadas na Região Sul e oito pertencentes à coleção da Embrapa. Foi utilizado o delineamento experimental de blocos ao acaso com três repetições, sendo realizados sete cortes. Foram avaliados: altura da planta, porcentagem e produção de matéria seca, rebrota, número de dias até o florescimento e produção de sementes. Observou-se variação entre as populações para todas as características avaliadas. A estimativa da produção total de matéria seca variou de 3654 kg/ha (população LE 284 a 8544 kg/ha (CNPGL 164. Os resultados demonstraram elevado potencial de produção de forragem entre as populações de azevém coletadas, sendo que algumas delas podem ser recomendadas para cultivo invernal na Região Sudeste.In the Southeast Region of Brazil, the winter season is characterized by poor quality and low availability of the pastures. In that region the annual ryegrass is one of the most recommended winter forage to be used for dairy cattle diets. The objective of this study was to evaluate the behavior of ryegrass populations under the Mata Atlantica environment. From the 30 evaluated populations, 22 were collected and eight belong to Embrapa's collection. A randomized blocks design with three replications was used, and seven cuts were done. Plant height, percent and dry matter production, regrowth, days to flowering and seed production were recorded. For all these parameters there were differences between populations. Total dry matter production varied from 3654 kg/ha (LE 284 to 8544 kg

  19. Quantitative Trait Locus (QTL meta-analysis and comparative genomics for candidate gene prediction in perennial ryegrass (Lolium perenne L.

    Directory of Open Access Journals (Sweden)

    Shinozuka Hiroshi

    2012-11-01

    Full Text Available Abstract Background In crop species, QTL analysis is commonly used for identification of factors contributing to variation of agronomically important traits. As an important pasture species, a large number of QTLs have been reported for perennial ryegrass based on analysis of biparental mapping populations. Further characterisation of those QTLs is, however, essential for utilisation in varietal improvement programs. Results A bibliographic survey of perennial ryegrass trait-dissection studies identified a total of 560 QTLs from previously published papers, of which 189, 270 and 101 were classified as morphology-, physiology- and resistance/tolerance-related loci, respectively. The collected dataset permitted a subsequent meta-QTL study and implementation of a cross-species candidate gene identification approach. A meta-QTL analysis based on use of the BioMercator software was performed to identify two consensus regions for pathogen resistance traits. Genes that are candidates for causal polymorphism underpinning perennial ryegrass QTLs were identified through in silico comparative mapping using rice databases, and 7 genes were assigned to the p150/112 reference map. Markers linked to the LpDGL1, LpPh1 and LpPIPK1 genes were located close to plant size, leaf extension time and heading date-related QTLs, respectively, suggesting that these genes may be functionally associated with important agronomic traits in perennial ryegrass. Conclusions Functional markers are valuable for QTL meta-analysis and comparative genomics. Enrichment of such genetic markers may permit further detailed characterisation of QTLs. The outcomes of QTL meta-analysis and comparative genomics studies may be useful for accelerated development of novel perennial ryegrass cultivars with desirable traits.

  20. Improved fructan accumulation in perennial ryegrass transformed with the onion fructosyltransferase genes 1-SST and 6G-FFT

    DEFF Research Database (Denmark)

    Gadegaard, Gitte; Didion, Thomas; Foiling, Marianne

    2008-01-01

    Carbohydrate limitation has been identified as a main cause of inefficient nitrogen use in ruminant animals, which feed mainly on fresh forage, hay and silage. This inefficiency results in suboptimal meat and milk productivity. One important molecular breeding strategy is to improve the nutritional...... value of ryegrass (Lolium perenne) by increasing the fructan content through expression of heterologous fructan biosynthetic genes. We developed perennial ryegrass Lines expressing sucrose:sucrose 1-fructosyltransferase and fructan:fructan 6G-fructosyltransferase genes from onion (Allium cepa) which...... exhibited up to a 3-fold increased fructan content. Further, the high fructan content was stable during the growth period, whereas the fructan content in an elite variety, marketed as a high sugar variety, dropped rapidly after reaching its maximum and subsequently remained low. (c) 2007 Elsevier GmbH. ALL...

  1. Distribution of polycyclic aromatic hydrocarbons in subcellular root tissues of ryegrass (Lolium multiflorum Lam.)

    Science.gov (United States)

    2010-01-01

    Background Because of the increasing quantity and high toxicity to humans of polycyclic aromatic hydrocarbons (PAHs) in the environment, several bioremediation mechanisms and protocols have been investigated to restore PAH-contaminated sites. The transport of organic contaminants among plant cells via tissues and their partition in roots, stalks, and leaves resulting from transpiration and lipid content have been extensively investigated. However, information about PAH distributions in intracellular tissues is lacking, thus limiting the further development of a mechanism-based phytoremediation strategy to improve treatment efficiency. Results Pyrene exhibited higher uptake and was more recalcitrant to metabolism in ryegrass roots than was phenanthrene. The kinetic processes of uptake from ryegrass culture medium revealed that these two PAHs were first adsorbed onto root cell walls, and they then penetrated cell membranes and were distributed in intracellular organelle fractions. At the beginning of uptake (< 50 h), adsorption to cell walls dominated the subcellular partitioning of the PAHs. After 96 h of uptake, the subcellular partition of PAHs approached a stable state in the plant water system, with the proportion of PAH distributed in subcellular fractions being controlled by the lipid contents of each component. Phenanthrene and pyrene primarily accumulated in plant root cell walls and organelles, with about 45% of PAHs in each of these two fractions, and the remainder was retained in the dissolved fraction of the cells. Because of its higher lipophilicity, pyrene displayed greater accumulation factors in subcellular walls and organelle fractions than did phenanthrene. Conclusions Transpiration and the lipid content of root cell fractions are the main drivers of the subcellular partition of PAHs in roots. Initially, PAHs adsorb to plant cell walls, and they then gradually diffuse into subcellular fractions of tissues. The lipid content of intracellular

  2. Seed yield response to N fertilization and potential of proximal sensing in Italian ryegrass seed crops

    DEFF Research Database (Denmark)

    Vleugels, Tim; Rijckaert, Georges; Gislum, René

    2017-01-01

    Italian ryegrass (Lolium multiflorum L.) seed crops are often routinely fertilized with a predetermined amount of nitrogen (N) fertilizer in spring. However, nitrate leaching and increasing N fertilizer prices require rationalized fertilizer applications without compromises in seed yield....... The objectives of this study were (1) to determine the seed yield response to N fertilization, and (2) to evaluate if NDVI values can reliably predict the N status in Italian ryegrass seed crops. During eight years, field trials were conducted with two cultivars ‘Melclips’ and ‘Melquatro’, and seven N strategies...... applied after the forage cut as single or split application: 0, 60, 60 + 30, 90, 90 + 30, 120 and 150 kg N ha−1. NDVI values were obtained with a ‘GreenSeeker’ optical sensor. Maximum seed yield was attained at 141 kg N ha−1 total available N (92 kg N ha−1 fertilized). Higher fertilizations only increased...

  3. Efeito de métodos e intensidades de pastejo sobre a ressemeadura natural de azevém anual = Effect of grazing methods and intensities on annual ryegrass under natural reseedling

    Directory of Open Access Journals (Sweden)

    Cristina Maria Pacheco Barbosa

    2008-10-01

    Full Text Available Este trabalho foi conduzido na E.E.A da UFRGS/RS (30°05’S e 51°39’W com o objetivo de avaliar o efeito de métodos e intensidades de pastejo na dinâmica populacional de azevém (Lolium multiflorum Lam. em ressemeadura natural. Conduziu-se a pastagem em dois métodos de pastejo (lotação contínua e rotacionada e duas intensidades de pastejo (moderada e baixa, em um delineamento em blocos casualizados, em esquema fatorial com três repetições (2x2x3. No ano seguinte, após um ciclo de lavoura de soja no verão, foi contado o número de perfilhos de azevém estabelecidos via essemeadura natural. Os resultados demonstraram não ter havido interação (p > 0,05 entre os métodos e as intensidades de pastejo, e seus efeitos foram analisados de forma independente. Enquanto os diferentes métodos de pastejo não afetaram a ressemeadura do azevém (p = 0,4636, asdiferentes intensidades de pastejo a influenciaram significativamente (p = 0,0003. O número de perfilhos de azevém estabelecidos via ressemeadura natural, na intensidade de pastejo baixa, foi maior (6.776 perfilhos m-2 do que na intensidade de pastejo moderada(211 perfilhos m-2. O controle da intensidade de pastejo é um fator determinante para a manutenção do azevém em sistemas de produção baseados na persistência dessa forrageira via ressemeadura natural.This work was conducted at EEA/UFRGS, in Eldorado do Sul, RioGrande do Sul state, Brazil (30°05’S e 51°39’W, to evaluate the effects of different grazing intensities and methods on the population dynamics of ryegrass (Lolium multiflorum Lam. under natural reseedling. Two grazing intensities (moderate and low were used, under continuous and rotational grazing. The experimental design included randomized blocks with 2x2x3 factorial arrangements (2 grazing intensities x 2 grazing methods x 3 replicates.The following year, the fields were desiccated with herbicides and a soybean plant crop cycle was established during the

  4. Exogenous melatonin suppresses dark-induced leaf senescence by activating the superoxide dismutase-catalase antioxidant pathway and down-regulating chlorophyll degradation in excised leaves of perennial ryegrass (Lolium perenne L.

    Directory of Open Access Journals (Sweden)

    Jing Zhang

    2016-10-01

    Full Text Available Leaf senescence is a typical symptom in plants exposed to dark and may be regulated by plant growth regulators. The objective of this study was to determine whether exogenous application of melatonin (N-acetyl-5-methoxytryptamine suppresses dark-induced leaf senescence and the effects of melatonin on reactive oxygen species (ROS scavenging system and chlorophyll degradation pathway in perennial grass species. Mature perennial ryegrass (Lolium perenne L. cv. ‘Pinnacle’ leaves were excised and incubated in 3 mM 2-(N-morpholino ethanesulfonic buffer (pH 5.8 supplemented with melatonin or water (control and exposed to dark treatment for 8 d. Leaves treated with melatonin maintained significantly higher endogenous melatonin level, chlorophyll content, photochemical efficiency, and cell membrane stability expressed by lower electrolyte leakage and malondialdehyde (MDA content compared to the control. Exogenous melatonin treatment also reduced the transcript level of chlorophyll degradation-associated genes and senescence marker genes (LpSAG12.1, Lph36, and Lpl69 during the dark treatment. The endogenous O2- production rate and H2O2 content were significantly lower in these excised leaves treated with melatonin compared to the water control. Exogenous melatonin treatment caused increases in enzymatic activity and transcript levels of superoxide dismutase and catalase but had no significant effects on ascorbate peroxidase, glutathione reductase, dehydroascorbate reductase, and monohydroascorbate reductase. The content of non-enzymatic antioxidants, such as ascorbate and dehydroascorbate, were decreased by melatonin treatment, while the content of glutathione and oxidized glutathione was not affected by melatonin. These results suggest that the suppression of dark-induced leaf senescence by exogenous melatonin may be associated with its roles in regulating ROS scavenging through activating the superoxide dismutase-catalase enzymatic antioxidant

  5. Identificação de biótipos de azevém (Lolium multiflorum resistentes ao herbicida glyphosate em pomares de maçã Identification of glyphosate-resistant ryegrass (Lolium multiflorum biotypes in apple orchards

    Directory of Open Access Journals (Sweden)

    L. Vargas

    2004-12-01

    geral, evidenciam que o biótipo sensível é facilmente controlado com o herbicida glyphosate e pelos demais herbicidas pós-emergentes avaliados, independentemente do estádio vegetativo. Demonstram, ainda, que o biótipo resistente apresenta-se, igualmente ao biótipo sensível, altamente suscetível aos herbicidas com mecanismo de ação distinto daquele do glyphosate. No entanto, o biótipo resistente apresenta baixa resposta ao herbicida glyphosate, mesmo se este for empregado em altas doses, evidenciando ter adquirido resistência a esse produto.Glyphosate is a wide spectrum herbicide used for over 15 years in apple orchards in Vacaria-RS for weed control in rows of trees. Usually, 3 to 4 applications per year are made at a rate of 720 to 1080 g a.e. glyphosate ha-1 (2 to 3 L ha-1 of commercial product. Ryegrass (Lolium multiflorum is a common weed in orchards and traditionally sensitive to glyphosate. However, in the last years, some ryegrass plants have not been found to show significant toxicity symptoms after treatment with glyphosate, suggesting that they acquired resistance to this product. To evaluate the response of a ryegrass plant population to glyphosate, one field and two greenhouse experiments were carried out. The field experiment treatments had increasing rates of glyphosate (0; 360; 720; 1,440; 2,880; 5,760 and 11,520 g a.e. ha-1, in addition to the herbicides paraquat, glufosinate-ammonium, haloxyfop and diclofop-methyl as standards, sprayed at two different vegetative growth stages of ryegrass. The greenhouse experiments had increasing rates of glyphosate (0; 360; 720; 1,440; 2,880 and 5,760 g a.e. ha-1 plus the above listed check herbicides sprayed on biotypes considered resistant and on plants of one susceptible biotype. In the second greenhouse experiment, glyphosate rates (720; 1,440; 2,880; 720 + 720 and 720 + 1,440 g a.e. ha-1 were sprayed in single and sequential applications, in addition to the herbicides paraquat, glufosinate

  6. Qualidade de sementes de Lolium multiflorum tetraploide comercializadas em Santa Catarina

    Directory of Open Access Journals (Sweden)

    Ricardo Miotto Ternus

    2017-02-01

    Full Text Available Na região Sul do Brasil, no período do inverno o azevém (Lolium multiflorum Lam se torna fundamental para a formação de pastagens. No entanto, o uso e a comercialização de sementes de azevém tetraploide têm crescido em relação aos diploides, devido, principalmente, a qualidade superior de suas sementes. O objetivo do trabalho foi avaliar a qualidade das sementes de azevém tetraploide, comercializadas no Estado de Santa Catarina. Foram utilizados seis lotes de sementes de azevém tetraploide da cultivar Barjumbo, oriundos de diferentes estabelecimentos comerciais do Estado de Santa Catarina. Cada lote de semente foi obtido a partir de coleta oficial. Buscaram-se lotes de sementes da categoria certificada, sendo dois lotes de cada país produtor (Argentina, Brasil e Uruguai. Avaliou-se a qualidade física e fisiológica a partir dos testes de pureza física, massa de mil sementes, teste de germinação, primeira contagem de germinação, comprimento da parte aérea e da raiz e massa seca da área e da raiz. Os resultados demonstram que 100% dos lotes analisados atendem os padrões legais de pureza física e germinação para a comercialização de sementes, independente da origem. Para o teste de germinação os resultados obtidos foram 27% superiores ao padrão legal. Os lotes de sementes de azevém tetraploides nacionais comercializados em Santa Catarina, mesmo apresentando-se dentro dos padrões legais para os testes de pureza física e germinação, apresentaram menor vigor quando comparados aos lotes oriundos da Argentina e Uruguai.Quality of Lolium multiflorum tetraploide seeds marketed in Santa CatarinaAbstract: In the southern region of Brazil, during the winter period ryegrass becomes essential for pasture formation. The use and commercialization of tetraploid ryegrass seeds has grown in relation to diploids, mainly due to the superior quality of their seeds. The objective of this work was to evaluate the quality of tetraploid

  7. Enteric methane production and ruminal fermentation of forage brassica diets fed in continuous culture

    Science.gov (United States)

    The aim of the current study was to determine nutrient digestibility, VFA production, N metabolism, and CH4 production of canola (Brassica napus L.), rapeseed (B. napus L.), turnip (B. rapa L.), and annual ryegrass (Lolium multiflorum Lam.) fed with orchardgrass (Dactylis glomerata L.) in continuous...

  8. Accurate Determination of Platinum, Palladium, and Rhodium in Ryegrass using Collision Cell Inductively Coupled Plasma Mass Spectrometry with Xenon as Collision Gas

    International Nuclear Information System (INIS)

    Amr, M.A.

    2011-01-01

    Inductively coupled plasma mass spectrometry with an octupole collision cell was used for determination of Pt, Pd and Rh in ryegrass (Lolium multiflorum) which was grown hydroponically. Xenon was used as a collision gas to reduce serious polyatomic interferences formed by combination of matrix elements such as CI, Cu, Hf, Sr, Zn, Zr, Y and REE with O, N, C, and Ar. The detection limits for Pt, Pd and Rh in spiked ryegrass are 1.8, 4.2, and 0.8 ppt, respectively. The results for Pt, Pd and Rh in reference materials (NIST SRM 2557, recycled monolith auto catalyst) are in agreement with the certified values. The bioaccumulation of Pt, Pd and Rh by ryegrass grown hydroponically with nutrient solutions containing Pt, Pd and Rh was studied. The obtained results showed that most of the studied metals were accumulated in roots, and only a small fraction was metabolized and transported to leaves. The highest bioaccumulation factors were obtained for Pd and Rh in roots and for Pt in leaves

  9. New chloroplast microsatellite markers suitable for assessing genetic diversity of Lolium perenne and other related grass species.

    Science.gov (United States)

    Diekmann, Kerstin; Hodkinson, Trevor R; Barth, Susanne

    2012-11-01

    Lolium perenne (perennial ryegrass) is the most important forage grass species of temperate regions. We have previously released the chloroplast genome sequence of L. perenne 'Cashel'. Here nine chloroplast microsatellite markers are published, which were designed based on knowledge about genetically variable regions within the L. perenne chloroplast genome. These markers were successfully used for characterizing the genetic diversity in Lolium and different grass species. Chloroplast genomes of 14 Poaceae taxa were screened for mononucleotide microsatellite repeat regions and primers designed for their amplification from nine loci. The potential of these markers to assess genetic diversity was evaluated on a set of 16 Irish and 15 European L. perenne ecotypes, nine L. perenne cultivars, other Lolium taxa and other grass species. All analysed Poaceae chloroplast genomes contained more than 200 mononucleotide repeats (chloroplast simple sequence repeats, cpSSRs) of at least 7 bp in length, concentrated mainly in the large single copy region of the genome. Nucleotide composition varied considerably among subfamilies (with Pooideae biased towards poly A repeats). The nine new markers distinguish L. perenne from all non-Lolium taxa. TeaCpSSR28 was able to distinguish between all Lolium species and Lolium multiflorum due to an elongation of an A(8) mononucleotide repeat in L. multiflorum. TeaCpSSR31 detected a considerable degree of microsatellite length variation and single nucleotide polymorphism. TeaCpSSR27 revealed variation within some L. perenne accessions due to a 44-bp indel and was hence readily detected by simple agarose gel electrophoresis. Smaller insertion/deletion events or single nucleotide polymorphisms detected by these new markers could be visualized by polyacrylamide gel electrophoresis or DNA sequencing, respectively. The new markers are a valuable tool for plant breeding companies, seed testing agencies and the wider scientific community due to

  10. Nitrogen accumulation and residual effects of nitrogen catch crops

    DEFF Research Database (Denmark)

    Jensen, E.S.

    1991-01-01

    The nitrogen accumulation in Italian ryegrass (Lolium multiflorum Lam.), perennial ryegrass (Lolium perenne L.), white mustard (Sinapis alba L.) and tansy phacelia (Phacelia tanacetifolia L.), under- or aftersown as nitrogen catch crops to spring barley (Hordeum vulgare L.) and field pea (Pisum s...

  11. An arbuscular mycorrhizal fungus and Epichloë festucae var. lolii reduce Bipolaris sorokiniana disease incidence and improve perennial ryegrass growth.

    Science.gov (United States)

    Li, Fang; Guo, Yan'e; Christensen, Michael J; Gao, Ping; Li, Yanzhong; Duan, Tingyu

    2018-02-01

    Leaf spot of perennial ryegrass (Lolium perenne) caused by Bipolaris sorokiniana is an important disease in temperate regions of the world. We designed this experiment to test for the combined effects of the arbuscular mycorrhizal (AM) fungus Claroideoglomus etunicatum and the grass endophyte fungus Epichloë festucae var. lolii on growth and disease occurrence in perennial ryegrass. The results show that C. etunicatum increased plant P uptake and total dry weight and that this beneficial effect was slightly enhanced when in association with the grass endophyte. The presence in plants of both the endophyte and B. sorokiniana decreased AM fungal colonization. Plants inoculated with B. sorokiniana showed the typical leaf spot symptoms 2 weeks after inoculation and the lowest disease incidence was with plants that were host to both C. etunicatum and E. festucae var. lolii. Plants with these two fungi had much higher activity of peroxidases (POD), superoxide dismutase (SOD) and catalase (CAT) and lower values of malondialdehyde (MDA) and hydrogen peroxide (H 2 O 2 ). The AM fungus C. etunicatum and the grass endophyte fungus E. festucae var. lolii have the potential to promote perennial ryegrass growth and resistance to B. sorokiniana leaf spot.

  12. Pollen-Mediated Movement of Herbicide Resistance Genes in Lolium rigidum.

    Directory of Open Access Journals (Sweden)

    Iñigo Loureiro

    Full Text Available The transfer of herbicide resistance genes by pollen is a major concern in cross-pollinated species such as annual ryegrass (Lolium rigidum. A two-year study was conducted in the greenhouse, under favorable conditions for pollination, to generate information on potential maximum cross-pollination. This maximum cross-pollination rate was 56.1%. A three-year field trial was also conducted to study the cross-pollination rates in terms of distance and orientation to an herbicide-resistant pollen source. Under field conditions, cross-pollination rates varied from 5.5% to 11.6% in plants adjacent to the pollen source and decreased with increasing distances (1.5 to 8.9% at 15 m distance and up to 4.1% at 25 m in the downwind direction. Environmental conditions influenced the cross-pollination both under greenhouse and field conditions. Data were fit to an exponential decay model to predict gene flow at increasing distances. This model predicted an average gene flow of 7.1% when the pollen donor and recipient plants were at 0 m distance from each other. Pollen-mediated gene flow declined by 50% at 16.7 m from the pollen source, yet under downwind conditions gene flow of 5.2% was predicted at 25 m, the farthest distance studied. Knowledge of cross-pollination rates will be useful for assessing the spread of herbicide resistance genes in L. rigidum and in developing appropriate strategies for its mitigation.

  13. INGESTIVE BEHAVIOR OF GOATS IN RYEGRASS AND BLACK OAT PASTURES IN PURE OR MIXTURE CULTURE COMPORTAMENTO INGESTIVO DE CAPRINOS EM PASTAGEM DE AZEVÉM E AVEIA PRETA EM CULTIVO PURO E CONSORCIADO

    Directory of Open Access Journals (Sweden)

    Alda Lúcia Gomes Monteiro

    2009-07-01

    Full Text Available The experiment was realized in Campo Largo, PR, where the ingestive behavior of goats was evaluated under ryegrass (Lolium multiflorum Lam. and black oat (Avena strigosa Schreb pastures in pure or mixture culture, in the period of 04/07/2004 to 05/08/2004. The grasses were applied in poles of 630 m² each, and the experimental design was placed in randomized blocks with three treatments and three repetitions. Twelve female goats were distributed in three experimental poles with four goats each for grazing evaluations. Previously to the evaluations of the animals the measurements of the pasture were obtained, which included height, total mass of forage and of the compounds leaf and steam. The goats were evaluated by preference and ingestion rate. The averages of pastures height was higher (p>0.05 in ryegrass and mixture, and in other pastures evaluations ryegrass was superior (p<0.05 to the others treatments. The grazing time of goats in ryegrass and black oat was superior (p<0.05 to the mixture. The bite rate per minute was higher (p<0.05 in black oat. The goats demonstrated preference for ryegrass and black oat in pure culture.
     
    KEY WORDS: Avena strigosa Schreb, bite, goats, Lolium multiflorum Lam, preference. The experiment was realized in Campo Largo – PR, where the ingestive behavior of goats was evaluated under ryegrass (Lolium multiflorum Lam. and black oat (Avena strigosa Schreb pastures in pure or mixture culture, in the period of 04/07/2004 to 05/08/2004. The grasses were applied in poles of 630 m² each, and the experimental design was placed in randomized blocks with three treatments and three repetitions. Twelve female goats were distributed in three experimental poles with four goats each for grazing evaluations. Previously to the evaluations of the animals the measurements of the pasture were obtained, which included height, total mass of forage and of the compounds leaf and steam. The goats were evaluated by

  14. Effect of Winter Cover Crops on Soil Nitrogen Availability, Corn Yield, and Nitrate Leaching

    OpenAIRE

    Kuo, S.; Huang, B.; Bembenek, R.

    2001-01-01

    Biculture of nonlegumes and legumes could serve as cover crops for increasing main crop yield, while reducing NO3 leaching. This study, conducted from 1994 to 1999, determined the effect of monocultured cereal rye (Secale cereale L.), annual ryegrass (Lolium multiflorum), and hairy vetch (Vicia villosa), and bicultured rye/vetch and ryegrass/vetch on N availability in soil, corn (Zea mays L.) yield, and NO3-N leaching in a silt loam soil. The field had been in corn and cover crop rotation sin...

  15. Producción de biomasa y costos de producción de pastos estrella africana (Cynodon nlemfuensis, kikuyo (Kikuyuocloa clandestina y ryegrass perenne (Lolium perenne en lecherías de Costa Rica

    Directory of Open Access Journals (Sweden)

    Luis Villalobos

    2013-01-01

    Full Text Available Se evaluó la producción de biomasa, los costos de producción y el costo del kilogramo de materia seca en los pastos kikuyo (Kikuyuocloa clandestina, ryegrass perenne (Lolium perenne y estrella africana (Cynodon nlemfuensis, a lo largo de un año, en 8 fincas comerciales ubicadas en las provincias de Cartago (2, San José (2 y Alajuela (4. La producción de biomasa promedio por ciclo para los 3 pastos fue de 3395 kg.ha-1 MS; la producción anual se ve influenciada por los días de recuperación de cada especie, mostrando valores de 40 170, 38 731 y 28 995 kg.ha-1 de MS para los pastos estrella africana, kikuyo y ryegrass perenne, respectivamente. La producción de biomasa varía durante el año y en las épocas de mayor producción de esa biomasa, los animales tienen un menor aprovechamiento de la pastura en términos porcentuales, debido a que la carga animal, los períodos de permanencia y las áreas de pastoreo no se ajustan a la disponibilidad de forraje. Los costos anuales de mano de obra, insumos y tierra promedio fueron de 72.433, 505.515 y 18.760 colones.ha-1, respectiva- mente; siendo los insumos el rubro con un peso relativo mayor en la estructura de costos de las fincas en pastoreo. Los costos del kg de MS producido y consumido, para los 3 pastos evaluados, fueron de 16,6 y 44,4 colones respectivamente, siendo el aprovechamiento que los animales hacen de las pasturas el determinante del costo del material consumido. Las fincas con mayor inversión anual en pasturas, mostraron un mayor retorno en kg.ha-1 leche.

  16. Effect of silage from ryegrass intercropped with winter or common vetch for grazing dairy cows in small-scale dairy systems in Mexico.

    Science.gov (United States)

    Hernández-Ortega, Martha; Heredia-Nava, Darwin; Espinoza-Ortega, Angelica; Sánchez-Vera, Ernesto; Arriaga-Jordán, Carlos M

    2011-06-01

    The objective was to determine the effect of including silages of annual ryegrass (Lolium multiflorum) intercropped with winter vetch (Vicia villosa) (ARG-VV) or with common vetch (Vicia sativa) (ARG-VS) compared with maize silage (MS) on milk yield and milk composition of dairy cows grazing cultivated perennial ryegrass-white clover pastures with supplemented concentrate during the dry season. Six Holstein dairy cows with a mean yield of 19.0 kg/cow/day at the beginning of the experiment were randomly assigned to a 3 × 3 repeated Latin square. Treatments were: 8 h/day intensive grazing, 3.6 kg of dry matter (DM) per cow per day of concentrate plus MS, and ARG-VV or ARG-VS ad libitum at a stocking rate of 3.0 cows/ha for three experimental periods of 3 weeks each. Milk yield (MY) and milk composition, live weight and body condition score as well as silage and concentrate intakes were recorded during the third week of each experimental period, and pasture intake was estimated indirectly from utilised metabolisable energy. Economic analysis was obtained by preparing partial budgets. There were no statistical differences (P > 0.10) in MY, milk fat or protein content nor for live weight, but there was significant difference (P dairy production systems in the dry season as it is comparable to MS in animal performance and slightly better in economic terms.

  17. A comparative study of molecular and morphological methods of describing relationships between perennial ryegrass (Lolium perenne L.) varieties

    NARCIS (Netherlands)

    Roldán-Ruiz, I.; Eeuwijk, van F.A.; Gilliland, T.J.; Dubreuil, P.; Dillmann, C.; Lallemand, J.; Loose, De M.; Baril, C.P.

    2001-01-01

    A sample set of registered perennial ryegrass varieties was used to compare how morphological characterisation and AFLP® (AFLP® is a registered trademark of Keygene N.V.) and STS molecular markers described variety relationships. All the varieties were confirmed as morphologically distinct, and both

  18. Cultivar identification by means of isoenzymes 2. Genetic variation at 4 enzyme loci in diploid ryegrass lolium-spp

    DEFF Research Database (Denmark)

    Nielsen, G.; Østergaard, H.; Johansen, Henrik

    1985-01-01

    gel electrophoresis. Cultivars were pairwise compared by means of allelic frequencies assuming Hardy-Weinberg proportions. At first, the comparisons were carried out for each locus separately. The 2 loci Pgi-2 and Got-3 distinguished perennial ryegrass cultivars fairly well, but the discrimination...

  19. Analysis of DNA methylation of perennial ryegrass under drought using the methylation-sensitive amplification polymorphism (MSAP) technique.

    Science.gov (United States)

    Tang, Xiao-Mei; Tao, Xiang; Wang, Yan; Ma, Dong-Wei; Li, Dan; Yang, Hong; Ma, Xin-Rong

    2014-12-01

    Perennial ryegrass (Lolium perenne), an excellent grass for forage and turf, is widespread in temperate regions. Drought is an important factor that limits its growth, distribution, and yield. DNA methylation affects gene expression and plays an important role in adaptation to adverse environments. In this study, the DNA methylation changes in perennial ryegrass under drought stress were assessed using methylation-sensitive amplified polymorphism (MSAP). After 15 days of drought stress treatment, the plant height was less than half of the control, and the leaves were smaller and darker. Genome-wide, a total of 652 CCGG sites were detected by MSAP. The total methylation level was 57.67 and 47.39 % in the control and drought treatment, respectively, indicating a decrease of 10.28 % due to drought exposure. Fifteen differentially displayed DNA fragments in MSAP profiles were cloned for sequencing analysis. The results showed that most of the genes involved in stress responses. The relative expression levels revealed that three demethylated fragments were up-regulated. The expression of a predicted retrotransposon increased significantly, changing from hypermethylation to non-methylation. Although the extent of methylation in two other genes decreased, the sites of methylation remained, and the expression increased only slightly. All of these results suggested that drought stress decreased the total DNA methylation level in perennial ryegrass and demethylation up-regulated related gene expressions and that the extent of methylation was negatively correlated with expression. Overall, the induced epigenetic changes in genome probably are an important regulatory mechanism for acclimating perennial ryegrass to drought and possibly other environmental stresses.

  20. Olivine weathering in soil, and its effects on growth and nutrient uptake in Ryegrass (Lolium perenne L.: a pot experiment.

    Directory of Open Access Journals (Sweden)

    Hein F M ten Berge

    Full Text Available Mineral carbonation of basic silicate minerals regulates atmospheric CO(2 on geological time scales by locking up carbon. Mining and spreading onto the earth's surface of fast-weathering silicates, such as olivine, has been proposed to speed up this natural CO(2 sequestration ('enhanced weathering'. While agriculture may offer an existing infrastructure, weathering rate and impacts on soil and plant are largely unknown. Our objectives were to assess weathering of olivine in soil, and its effects on plant growth and nutrient uptake. In a pot experiment with perennial ryegrass (Lolium perenne L., weathering during 32 weeks was inferred from bioavailability of magnesium (Mg in soil and plant. Olivine doses were equivalent to 1630 (OLIV1, 8150, 40700 and 204000 (OLIV4 kg ha(-1. Alternatively, the soluble Mg salt kieserite was applied for reference. Olivine increased plant growth (+15.6% and plant K concentration (+16.5% in OLIV4. At all doses, olivine increased bioavailability of Mg and Ni in soil, as well as uptake of Mg, Si and Ni in plants. Olivine suppressed Ca uptake. Weathering estimated from a Mg balance was equivalent to 240 kg ha(-1 (14.8% of dose, OLIV1 to 2240 kg ha(-1 (1.1%, OLIV4. This corresponds to gross CO(2 sequestration of 290 to 2690 kg ha(-1 (29 10(3 to 269 10(3 kg km(-2. Alternatively, weathering estimated from similarity with kieserite treatments ranged from 13% to 58% for OLIV1. The Olsen model for olivine carbonation predicted 4.0% to 9.0% weathering for our case, independent of olivine dose. Our % values observed at high doses were smaller than this, suggesting negative feedbacks in soil. Yet, weathering appears fast enough to support the 'enhanced weathering' concept. In agriculture, olivine doses must remain within limits to avoid imbalances in plant nutrition, notably at low Ca availability; and to avoid Ni accumulation in soil and crop.

  1. Cool-season annual pastures with clovers to supplement wintering beef cows nursing calves

    Directory of Open Access Journals (Sweden)

    Gunter Stacey A

    2012-07-01

    Full Text Available Abstract In December of 3 years, 87 beef cows with nursing calves (594 ± 9.8 kg; calving season, September to November at side were stratified by body condition score, body weight, cow age, and calf gender and divided randomly into 6 groups assigned to 1 of 6 cool-season annual pastures (0.45 ha/cow that had been interseeded into a dormant common bermudagrass (Cynodon dactylon [L.] Pers./bahiagrass (Paspalum notatum Flugge sod. Pastures contained 1 of the following 3 seeding mixtures (2 pastures/mixture: 1 wheat (Triticum aestivum L. and ryegrass (Lolium multiflorum Lam., WRG, 2 wheat and ryegrass plus red clover (Trifolium pretense L., WRR, or 3 wheat and ryegrass plus white (Trifolium repens L. and crimson clovers (Trifolium incarnatum L., WRW. All groups had ad libitum access to grass hay (12% crude protein; 58% total digestible nutrients. The second week in December, cow estrous cycles were synchronized and artificially inseminated. In late December, a bull was placed with each group for 60-d. Data were analyzed with an analysis of variance using a mixed model containing treatment as the fixed effect and year as the random effect. Body weight and condition scores did not differ (P ≥ 0.27 among cows between February and June. Calf birth weights or average daily gain did not differ (P ≥ 0.17 among treatments; however, calves grazing pastures with clovers did tend (P = 0.06 to weigh more than calves grazing grass only. Weaning weight per cow exposed to a bull was greater (P = 0.02 for WRR and WRW than WRG. Cows grazing winter-annual pastures containing clovers tended to wean more calf body weight per cow exposed to a bull than cows grazing the grass only pastures.

  2. Initial characterisation of low and high seed dormancy populations of Lolium rigidum produced by repeated selection.

    Science.gov (United States)

    Goggin, Danica E; Emery, R J Neil; Powles, Stephen B; Steadman, Kathryn J

    2010-10-15

    The physiological and biochemical bases of seed dormancy in Lolium rigidum (annual ryegrass) are largely unknown, and study of this process is complicated by the outcrossing nature of the species and the strong influence of environment on seed dormancy. In order to identify heritable biochemical factors contributing to seed dormancy in L. rigidum, seeds from a field-collected population were used to select sub-populations with consistently low or high seed dormancy over four generations. Low-dormancy seeds showed constitutive alpha-amylase activity prior to imbibition, higher concentrations of polyphenols and cis-zeatin, and lower abscisic acid and cis-zeatin riboside concentrations than high-dormancy seeds. Selection for high dormancy was associated with a reduction in response to dark-stratification for 21d at 20 degrees C (an effective means of releasing dormancy in the original, unselected population) over successive generations, but fluridone remained effective in breaking dormancy. Crossing of low- and high-dormancy populations indicated that dormancy level was not dependent upon the maternal genotype of the seed, and that the constitutive alpha-amylase activity and high seed anthocyanin concentrations characteristic of the low-dormancy populations were not correlated to high basal germination ability. Copyright (c) 2010 Elsevier GmbH. All rights reserved.

  3. Forage yield and quality response of annual ryegrass ( Lolium ...

    African Journals Online (AJOL)

    The dry matter (DM) content, in vitro organic matter digestibility (IVOMD), crude protein (CP) and metabolisable energy (ME) were higher in the treatments being irrigated once every two weeks. These results conclude that higher irrigation coupled with high N application significantly improved the dry matter yield, while water ...

  4. A Simple and Fast Kinetic Assay for the Determination of Fructan Exohydrolase Activity in Perennial Ryegrass (Lolium perenne L.)

    Czech Academy of Sciences Publication Activity Database

    Gasperl, A.; Morvan-Bertrand, A.; Prud'homme, M. P.; van der Graaff, E.; Roitsch, Thomas

    2015-01-01

    Roč. 6, dec (2015), s. 1154 ISSN 1664-462X R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : 1-FEH * enzymaticactivity * fructanexohydrolase * fructandegradation * kinetic assay * perennial ryegrass Subject RIV: EH - Ecology, Behaviour Impact factor: 4.495, year: 2015

  5. Predicting seed yield in perennial ryegrass using repeated canopy reflectance measurements and PLSR

    DEFF Research Database (Denmark)

    Gislum, René; Deleuran, Lise Christina; Boelt, Birte

    2009-01-01

    with first year seed crops using three sowing rates and three spring nitrogen (N) application rates. PLSR models were developed for each year and showed correlation coefficients of 0.71, 0.76, and 0.92, respectively. Regression coefficients showed in these experiments that the optimum time for canopy...... reflectance measurements was from approximately 600 cumulative growing degree-days (CGDD) to approximately 900 CGDD. This is the period just before and at heading of the seed crop. Furthermore, regression coefficients showed that information about N and water is important. The results support the development......Repeated canopy reflectance measurements together with partial least-squares regression (PLSR) were used to predict seed yield in perennial ryegrass (Lolium perenne L.). The measurements were performed during the spring and summer growing seasons of 2001 to 2003 in three field experiments...

  6. Comparative sequence analysis of VRN1 alleles of Lolium perenne with the co-linear regions in barley, wheat, and rice

    DEFF Research Database (Denmark)

    Asp, Torben; Byrne, Stephen; Gundlach, Heidrun

    2011-01-01

    Vernalization, a period of low temperature to induce transition from vegetative to reproductive state, is an important environmental stimulus for many cool season grasses. A key gene in the vernalization pathway in grasses is the VRN1 gene. The objective of this study was to identify causative...... polymorphism(s) at the VRN1 locus in perennial ryegrass (Lolium perenne) for variation in vernalization requirement. Two allelic Bacterial Artificial Chromosome clones of the VRN1 locus from the two genotypes Veyo and Falster with contrasting vernalization requirements were identified, sequenced...

  7. Investigation the Kinetic Models of Biological Removal of Petroleum Contaminated Soil Around Oil Pipeline Using Ryegrass

    Directory of Open Access Journals (Sweden)

    Elham Ghaheri

    2014-04-01

    Full Text Available The industrial revolution of the past century has resulted in significant damage to environmental resources such as air, water and soil. Petroleum contamination of soil is a serious problem throughout the oil producer countries. Remediation of petroleum contamination of soils is generally a slow and expensive process. Phytoremediation is a potentially less-damaging, cost-effective, but needs longer-term for remediation of contaminated land compared to the alternative methods. In this study the kinetics of petroleum hydrocarbon contaminated soils in Khozestan were investigated. For this paper Ryegrass (Lolium perenne plant selected and the decline of total petroleum hydrocarbon (TPH was analyzed after growth stage, every 10 days up to 90 days. The results of TPH concentration was fitted with zero-order kinetic, first-order kinetic and Higuchi model. The result indicated that degradation of TPH with presence of plants as a function of time was well fitted with the first-order kinetic model. The first-order rate constants (K and half-lives (T1/2 for TPH degradation were 0.0098 1/day and 71 day; respectively. The results of phytoremediation showed that there were 65% decreases in TPH concentration with Ryegrass during the 17 weeks.

  8. EST-derived SSR markers used as anchor loci for the construction of a consensus linkage map in ryegrass (Lolium spp.)

    NARCIS (Netherlands)

    Studer, B.; Kolliker, R.; Muylle, H.; Asp, T.; Frei, U.; Roldan-Ruiz, I.; Barre, P.; Tomaszewski, C.; Meally, H.; Barth, S.; Skot, L.; Armstead, I.P.; Dolstra, O.; Lubberstedt, T.

    2010-01-01

    Background: Genetic markers and linkage mapping are basic prerequisites for marker-assisted selection and map-based cloning. In the case of the key grassland species Lolium spp., numerous mapping populations have been developed and characterised for various traits. Although some genetic linkage maps

  9. Exogenous Classic Phytohormones Have Limited Regulatory Effects on Fructan and Primary Carbohydrate Metabolism in Perennial Ryegrass (Lolium perenne L.)

    Czech Academy of Sciences Publication Activity Database

    Gasperl, A.; Morvan-Bertrand, A.; Prud'homme, M. P.; van der Graaff, E.; Roitsch, Thomas

    2016-01-01

    Roč. 6, jan (2016), s. 1251 ISSN 1664-462X R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : enzymatic activity * fructan exohydrolase * fructan metabolism * fructosyltransferase * perennial ryegrass * phytohormones * primary carbohydrate metabolism Subject RIV: ED - Physiology Impact factor: 4.298, year: 2016

  10. Effects of coal spoil amendment on heavy metal accumulation and physiological aspects of ryegrass (Lolium perenne L.) growing in copper mine tailings.

    Science.gov (United States)

    Chu, Zhaoxia; Wang, Xingming; Wang, Yunmin; Liu, Guijian; Dong, Zhongbing; Lu, Xianwen; Chen, Guangzhou; Zha, Fugeng

    2017-12-21

    Copper mine tailings pose many threats to the surrounding environment and human health, and thus, their remediation is fundamental. Coal spoil is the waste by-product of coal mining and characterized by low levels of metals, high content of organic matter, and many essential microelements. This study was designed to evaluate the role of coal spoil on heavy uptake and physiological responses of Lolium perenne L. grown in copper mine tailings amended with coal spoil at rates of 0, 0.5, 1, 5, 10, and 20%. The results showed that applying coal spoil to copper mine tailings decreased the diethylenetriaminepentaacetic acid (DTPA)-extractable Cd, Cu, Pb, and Zn contents in tailings and reduced those metal contents in both roots and shoots of the plant. However, application of coal spoil increased the DTPA-extractable Cr concentration in tailings and also increased Cr uptake and accumulation by Lolium perenne L. The statistical analysis of physiological parameters indicated that chlorophyll and carotenoid increased at the lower amendments of coal spoil followed by a decrease compared to their respective controls. Protein content was enhanced at all the coal spoil amendments. When treated with coal spoil, the activities of superoxide dismutases (SOD), peroxidase (POD), and catalase (CAT) responded differently. CAT activity was inhibited, but POD activity was increased with increasing amendment ratio of coal spoil. SOD activity increased up to 1% coal spoil followed by a decrease. Overall, the addition of coal spoil decreased the oxidative stress in Lolium perenne L., reflected by the reduction in malondialdehyde (MDA) contents in the plant. It is concluded that coal spoil has the potential to stabilize most metals studied in copper mine tailings and ameliorate the harmful effects in Lolium perenne L. through changing the physiological attributes of the plant grown in copper mine tailings.

  11. Herbage Production, Nutritive Value and Grazing Preference of Diploid and Tetraploid Perennial Ryegrass Cultivars (Lolium perenne L. Producción de Fitomasa, Calidad Nutritiva y Preferencia de Pastoreo de Cultivares Diploides y Tetraploides de Ballica Perenne (Lolium perenne L.

    Directory of Open Access Journals (Sweden)

    Oscar A Balocchi

    2009-09-01

    Full Text Available The objective of this study was to determine, under the soil and climatic conditions of Southern Chile, the effect of the ploidy of perennial ryegrass (Lolium perenne L. cultivars on herbage production, nutritive value, grazing preference and utilization of pasture produced. This study was conducted in southern Chile, Valdivia Province, and was evaluated for 3 years. The tetraploid cultivars used were Quartet (4n, Gwendal (4n, Pastoral (4n and Napoleon (4n. The diploid cultivars were Anita (2n, Jumbo (2n, Aries (2n, and Yatsyn 1 (2n.When the average sward height reached 20 cm, all plots were simultaneously grazed by dairy cows for a period of 24 h. Before and after grazing, sward height, dry matter availability and nutritive value were evaluated. Grazing preference was visually assessed every 5 min for a period of 2.5 h after the afternoon milking. During the 3-year period 20 grazing events were evaluated. A randomized complete block design, with eight cultivars and three replicates, was used. Diploid cultivars showed greater herbage mass accumulation than tetraploid cultivars (P ≤ 0.05. No significant differences were obtained in the annual average crude protein content. Nevertheless, tetraploid cultivars showed a greater D value than diploid cultivars, except during the third year when the difference was not statistically significant. Dairy cows grazed more time on tetraploid cultivars. Considering, additionally, the residual herbage mass after grazing and the percentage of pasture utilization, diploid cultivars were less intensively grazed, suggesting a lower consumption by the cows.El objetivo de este estudio fue determinar, bajo las condiciones edafoclimáticas del sur de Chile, el efecto de la ploidía de cultivares de ballica perenne (Lolium perenne L. sobre el rendimiento de fitomasa, calidad nutricional, preferencia de pastoreo y porcentaje de utilización del forraje producido. El ensayo se realizó en el sur de Chile, provincia de

  12. Validity of accessible critical nitrogen dilution curves in perennial ryegrass for seed production

    DEFF Research Database (Denmark)

    Gislum, René; Boelt, Birte

    2009-01-01

    The objectives were to test if accessible critical nitrogen dilution curves (NDCs) in rapeseed, pea, alfalfa, tall fescue, wheat, annual ryegrass and linseed could be used in grass species for seed production and to develop a critical NDC especially in grass species for seed production. The criti......The objectives were to test if accessible critical nitrogen dilution curves (NDCs) in rapeseed, pea, alfalfa, tall fescue, wheat, annual ryegrass and linseed could be used in grass species for seed production and to develop a critical NDC especially in grass species for seed production...... the NDCs in tall fescue, alfalfa, pea and rapeseed. These findings should be used to continue the interesting and necessary work on developing a NDC in grass species for seed production....

  13. Induction of salicylic acid-mediated defense response in perennial ryegrass against infection by Magnaporthe oryzae.

    Science.gov (United States)

    Rahman, Alamgir; Kuldau, Gretchen A; Uddin, Wakar

    2014-06-01

    Incorporation of plant defense activators is an innovative approach to development of an integrated strategy for the management of turfgrass diseases. The effects of salicylic acid (SA), benzothiadiazole (BTH, chemical analog of SA), jasmonic acid (JA), and ethephon (ET, an ethylene-releasing compound) on development of gray leaf spot in perennial ryegrass (Lolium perenne L.) caused by Magnaporthe oryzae were evaluated. Gray leaf spot disease incidence and severity were significantly decreased when plants were treated prior to inoculation with SA, BTH, and partially by ET but not by JA. Accumulation of endogenous SA and elevated expression of pathogenesis-related (PR)-1, PR-3.1, and PR-5 genes were associated with inoculation of plants by M. oryzae. Treatment of plants with SA enhanced expression levels of PR-3.1 and PR-5 but did not affect the PR-1 level, whereas BTH treatment enhanced relative expression levels of all three PR genes. Microscopic observations of leaves inoculated with M. oryzae revealed higher frequencies of callose deposition at the penetration sites in SA- and BTH-treated plants compared with the control plants (treated with water). These results suggest that early and higher induction of these genes by systemic resistance inducers may provide perennial ryegrass with a substantial advantage to defend against infection by M. oryzae.

  14. Morphology and pollen viability of Lolium multiflorum Lam. Morfologia e viabilidade polínica de Lolium multiflorum Lam.

    Directory of Open Access Journals (Sweden)

    Renata de Castro Nunes

    2012-04-01

    Full Text Available Study and characterization of pollen grains are essential for different areas, especially taxonomy, genetic improvement, phylogeny, and paleobotany. As yet, there are no reports on pollen morphology of genotypes of naturalized Lolium multiflorum Lam., introduced cultivars or breeding populations, diploid or polyploid. Ten genotypes of annual ryegrass (L. multiflorum were evaluated for the viability of pollen grains using propionic carmine and Alexander's stains, while morphology was assessed by the acetolysis technique. Measures of polar axis (P, equatorial diameter (E, exine thickness, and analysis of pollen grains were obtained by scanning electron microscopy (SEM. All genotypes showed high rate of pollen viability (> 89% for both stains. There were differences between genotypes in the following quantitative traits: polar axis, equatorial diameter, exine, endexine, ektexine, and P/E ratio. Pollen grains were characterized as small, monoporates, with circular and non-prominent apertures. In addition to helping distinction of pollen grains, morphometric differences can be used later to compare ploidy levels, thus assisting in breeding programs of the species.O estudo e a caracterização do grão de pólen são fundamentais para diferentes áreas, em especial, para a taxonomia, o melhoramento genético, a filogenia e a paleobotânica. Para genótipos de Lolium multiflorum Lam., naturalizados no Brasil, cultivares introduzidas ou populações de melhoramento, diploides e poliploides, não existem relatos sobre a caracterização morfopolínica. Nesse trabalho foram analisados dez gentótipos de azevém anual (L. multiflorum. A viabilidade dos grãos de pólen foi verificada por coloração com os corantes carmim propiônico e Alexander e a morfologia por meio da técnica de acetólise, sendo obtidas medidas do eixo polar (P, do diâmetro equatorial (E, e da espessura da exina, e análise dos grãos de pólen por microscopia eletrônica de

  15. Identification of T-cell epitopes of Lol p 9, a major allergen of ryegrass (Lolium perenne) pollen.

    Science.gov (United States)

    Blaher, B; Suphioglu, C; Knox, R B; Singh, M B; McCluskey, J; Rolland, J M

    1996-07-01

    T-cell recognition of Lol p 9, a major allergen of ryegrass pollen, was investigated by using a T-cell line and T-cell clones generated from the peripheral blood of an atopic donor. The T-cell line reacted with purified Lol p 9, as well as with crude ryegrass pollen extract, but failed to cross-react with Bermuda grass pollen extract. All of six T-cell clones generated from this line proliferated in response to Lol p 9. Epitope mapping was carried out with a panel of 34 overlapping synthetic peptides, which spanned the entire sequence of the Lol p 9 12R isoform. The T-cell line responded to two of the peptides, Lol p 9 (105-116) and Lol p 9 (193-204), whereas reactivity with one or other of these peptides was shown by five T-cell clones. These two peptides contained sequences consistent with motifs previously reported for major histocompatibility complex class II-restricted peptides. HLA antibody blocking studies showed that presentation of peptide Lol p 9 (105-116) to one T-cell clone was HLA-DR-restricted; this clone expressed a T helper cell phenotype (CD3+, CD4+) and the T-cell receptor alpha beta. The identification of immunodominant T-cell epitope(s) on allergens is essential for devising safer and more effective immunotherapy strategies, which can interrupt the chain of events leading to allergic disease.

  16. Phenanthrene and Pyrene Modify the Composition and Structure of the Cultivable Endophytic Bacterial Community in Ryegrass (Lolium multiflorum Lam

    Directory of Open Access Journals (Sweden)

    Xuezhu Zhu

    2016-11-01

    Full Text Available This study provides new insights into the dynamics of bacterial community structure during phytoremediation. The communities of cultivable autochthonous endophytic bacteria in ryegrass exposed to polycyclic aromatic hydrocarbons (PAHs were investigated with regard to their potential to biodegrade PAHs. Bacterial counts and 16S rRNA gene sequence were used in the microbiological evaluation. A total of 33 endophytic bacterial strains were isolated from ryegrass plants, which represented 15 different genera and eight different classes, respectively. Moreover, PAH contamination modified the composition and structure of the endophytic bacterial community in the plants. Bacillus sp., Pantoea sp., Pseudomonas sp., Arthrobacter sp., Pedobacter sp. and Delftia sp. were only isolated from the seedlings exposed to PAHs. Furthermore, the dominant genera in roots shifted from Enterobacter sp. to Serratia sp., Bacillus sp., Pantoea sp., and Stenotrophomonas sp., which could highly biodegrade phenanthrene (PHE. However, the diversity of endophytic bacterial community was decreased by exposure to the mixture of PAHs, and increased by respective exposure to PHE and pyrene (PYR, while the abundance was increased by PAH exposure. The results clearly indicated that the exposure of plants to PAHs would be beneficial for improving the effectiveness of phytoremediation of PAHs.

  17. Forage grasses with lower uptake of caesium and strontium could provide ‘safer’ crops for radiologically contaminated areas

    Science.gov (United States)

    Beresford, Nicholas A.; Crout, Neil M. J.; Lovatt, J. Alan; Thomson, Russell; Broadley, Martin R.

    2017-01-01

    Substitution of a species or cultivar with higher uptake of an element by one with lower uptake has been proposed as a remediation strategy following accidental releases of radioactivity. However, despite the importance of pasture systems for radiological dose, species/cultivar substitution has not been thoroughly investigated for forage grasses. 397 cultivars from four forage grass species; hybrid ryegrass (Lolium perenne L. x Lolium multiflorum Lam.), perennial ryegrass (Lolium perenne L.), Italian ryegrass (Lolium multiflorum Lam.) and tall fescue (Festuca arundinacea Shreb.); were sampled from 19 field-based breeding experiments in Aberystwyth and Edinburgh (UK) in spring 2013 and analysed for caesium (Cs) and strontium (Sr) concentrations. In order to calculate concentration ratios (CRs; the concentration of an element in a plant in relation to the concentration in the soil), soils from the experiments were also analysed to calculate extractable concentrations of Cs and Sr. To test if cultivars have consistently low Cs and Sr concentration ratios, 17 hybrid ryegrass cultivars were sampled from both sites again in summer 2013 and spring and summer 2014. Tall fescue cultivars had lower Cs and Sr CRs than the other species. Three of the selected 17 hybrid ryegrass cultivars had consistently low Cs CRs, two had consistently low Sr CRs and one had consistently low Cs and Sr CRs. Cultivar substitution could reduce Cs CRs by up to 14-fold and Sr CRs by 4-fold in hybrid ryegrass. The identification of species and cultivars with consistently low CRs suggests that species or cultivar substitution could be an effective remediation strategy for contaminated areas. PMID:28459808

  18. Hydrocarbon degradation and plant colonization of selected bacterial strains isolated from the rhizsophere and plant interior of Italian ryegrass and Birdsfoot trefoil

    Science.gov (United States)

    Sohail, Y.; Andria, V.; Reichenauer, T. G.; Sessitsch, A.

    2009-04-01

    Hydrocarbon-degrading strains were isolated from the rhizosphere, root and shoot interior of Italian ryegrass (Lolium multiflorum var. Taurus), Birdsfoot trefoil (Lotus corniculatus var. Leo) grown in a soil contaminated with petroleum oil. Strains were tested regarding their phylogeny and their degradation efficiency. The most efficient strains were tested regarding their suitability to be applied for phytoremediation of diesel oils. Sterilized and non-sterilized agricultural soil, with and with out compost, were spiked with diesel and used for planting Italian ryegrass and birdsfoot trefoil. Four selected strains with high degradation activities, derived from the rhizosphere and plant interior, were selected for individual inoculation. Plants were harvested at flowering stage and plant biomass and hydrocarbon degradation was determined. Furthermore, it was investigated to which extent the inoculant strains were able to survive and colonize plants. Microbial community structures were analysed by 16S rRNA and alkB gene analysis. Results showed efficient colonization by the inoculant strains and improved degradation by the application of compost combined with inoculation as well as on microbial community structures will be presented.

  19. Componentes morfológicos e produção de forragem de pastagem de aveia e azevém manejada em diferentes alturas Morphological components and forage production of oat (Avena strigosa, Schreb and annual ryegrass (Lolium multiflorum, Lam pasture managed at different heights

    Directory of Open Access Journals (Sweden)

    Angelo Antonio Queirolo Aguinaga

    2008-09-01

    Full Text Available Avaliou-se a dinâmica de produção de forragem em pastagem de aveia-preta (Avena strigosa Schreb e azevém (Lolium multiflorum Lam manejada em diversas alturas de manejo com o objetivo de evidenciar as potencialidades dessa mistura em sistemas de integração lavoura-pecuária. Os tratamentos consistiram de quatro alturas de manejo da pastagem (10; 20; 30 e 40 cm, medidas com bastão graduado e avaliadas em blocos casualizados com três repetições. O método de pastejo foi contínuo, com taxa de lotação variável. Utilizaram-se bezerros de corte mestiços com 10 meses de idade e peso médio inicial de 210 kg, respectivamente. As características da pastagem estudadas foram: massa de forragem (MF; taxa de acúmulo de forragem (TAC; produção total de forragem (PTMS; e quantificação dos componentes morfológicos da pastagem (colmo, lâmina e material morto. A massa de forragem aumentou de forma linear de acordo com a altura do pasto, uma vez que, para cada cm de aumento na altura superior a 10 cm, a matéria seca aumentou aproximadamente 90 kg/ha. Não houve efeito das alturas da pastagem sobre a TAC ou sobre a PTMS, cujos valores médios foram de 66,8 kg/ha/dia de MS e 10.721 kg/ha de MS, respectivamente. A porcentagem de folhas de azevém foi maior que a de folhas de aveia nos três períodos de avaliação e, na altura de 10 cm, foi superior à obtida nas demais alturas na última avaliação (em torno de 20% da participação total da massa de forragem. A aveia apresenta rápido desenvolvimento inicial e diminuição na produção nos períodos posteriores de desenvolvimento.Forage growth dynamic in an Oat (Avena strigosa, Schreb + Ryegrass (Lolium multiflorum, Lam pasture managed at different grazing heights was evaluated in order to access the mixed-sward potential in a crop-livestock integrated system. Treatments were four sward grazing heights (10, 20, 30, and 40 cm, measured with a sward-stick. The experimental design was a

  20. Sheep numbers required for dry matter digestibility evaluations when fed fresh perennial ryegrass or forage rape.

    Science.gov (United States)

    Sun, Xuezhao; Krijgsman, Linda; Waghorn, Garry C; Kjestrup, Holly; Koolaard, John; Pacheco, David

    2017-03-01

    Research trials with fresh forages often require accurate and precise measurement of digestibility and variation in digestion between individuals, and the duration of measurement periods needs to be established to ensure reliable data are obtained. The variation is likely to be greater when freshly harvested feeds are given, such as perennial ryegrass ( Lolium perenne L.) and forage rape ( Brassica napus L.), because the nutrient composition changes over time and in response to weather conditions. Daily feed intake and faeces output data from a digestibility trial with these forages were used to calculate the effects of differing lengths of the measurement period and differing numbers of sheep, on the precision of digestibility, with a view towards development of a protocol. Sixteen lambs aged 8 months and weighing 33 kg at the commencement of the trial were fed either perennial ryegrass or forage rape (8/treatment group) over 2 periods with 35 d between measurements. They had been acclimatised to the diets, having grazed them for 42 d prior to 11 days of indoor measurements. The sheep numbers required for a digestibility trial with different combinations of acclimatisation and measurement period lengths were subsequently calculated for 3 levels of imposed precision upon the estimate of mean dry matter (DM) digestibility. It is recommended that if the standard error of the mean for digestibility is equal to or higher than 5 g/kg DM, and if sheep are already used to a fresh perennial ryegrass or forage rape diet, then a minimum of 6 animals are needed and 4 acclimatisation days being fed individually in metabolic crates followed by 7 days of measurement.

  1. EST-derived SSR markers used as anchor loci for the construction of a consensus linkage map in ryegrass (Lolium spp.)

    DEFF Research Database (Denmark)

    Studer, Bruno; Kölliker, Roland; Muylle, Hilde

    2010-01-01

    Background Genetic markers and linkage mapping are basic prerequisites for marker-assisted selection and map-based cloning. In the case of the key grassland species Lolium spp., numerous mapping populations have been developed and characterised for various traits. Although some genetic linkage maps...

  2. Synergistic Effects of Bacillus amyloliquefaciens (GB03) and Water Retaining Agent on Drought Tolerance of Perennial Ryegrass.

    Science.gov (United States)

    Su, An-Yu; Niu, Shu-Qi; Liu, Yuan-Zheng; He, Ao-Lei; Zhao, Qi; Paré, Paul W; Li, Meng-Fei; Han, Qing-Qing; Ali Khan, Sardar; Zhang, Jin-Lin

    2017-12-11

    Water retaining agent (WRA) is widely used for soil erosion control and agricultural water saving. Here, we evaluated the effects of the combination of beneficial soil bacterium Bacillus amyloliquefaciens strain GB03 and WRA (the compound is super absorbent hydrogels) on drought tolerance of perennial ryegrass ( Lolium perenne L.). Seedlings were subjected to natural drought for maximum 20 days by stopping watering and then rewatered for seven days. Plant survival rate, biomass, photosynthesis, water status and leaf cell membrane integrity were measured. The results showed that under severe drought stress (20-day natural drought), compared to control, GB03, WRA and GB03+WRA all significantly improved shoot fresh weight, dry weight, relative water content (RWC) and chlorophyll content and decreased leaf relative electric conductivity (REC) and leaf malondialdehyde (MDA) content; GB03+WRA significantly enhanced chlorophyll content compared to control and other two treatments. Seven days after rewatering, GB03, WRA and GB03+WRA all significantly enhanced plant survival rate, biomass, RWC and maintained chlorophyll content compared to control; GB03+WRA significantly enhanced plant survival rate, biomass and chlorophyll content compared to control and other two treatments. The results established that GB03 together with water retaining agent promotes ryegrass growth under drought conditions by improving survival rate and maintaining chlorophyll content.

  3. Comportamento ingestivo de ovinos no período diurno em pastagem de azevém anual em diferentes estádios fenológicos Diurnal ingestive behavior of sheep grazing annual ryegrass at different phenological growth stages

    Directory of Open Access Journals (Sweden)

    Renato Borges de Medeiros

    2007-02-01

    Full Text Available Este trabalho foi realizado com o objetivo de avaliar o comportamento ingestivo no período diurno de ovelhas Corriedale em final de gestação e início de lactação sob pastejo em uma área de 1,3 ha de azevém anual (Lolium multiflorum Lam. nos estádios vegetativo, pré-florescimento e de florescimento. Foram determinados o tempo de pastejo, a taxa de bocado, o tamanho de bocado, o teor de PB da forragem e os consumos de MS e PB. Os maiores tempos de pastejo e de consumo de MS e PB, para os três estádios do azevém, foram observados ao final da tarde. Nos estádios vegetativo e pré-florescimento, os tempos de pastejo e os consumos de MS e PB registrados no início da manhã (7 às 7h50 foram semelhantes aos verificados no final da tarde. No estádio pré-florescimento, registraram-se ainda nestes horários de pico de pastejo as maiores taxas de bocado e peso de bocado, as quais, associadas ao maior tempo de pastejo, determinaram os maiores consumos de forragem ao longo do dia. Os menores tempos de pastejo ocorreram das 8 às 9h50 durante o estádio vegetativo; das 8 às 8h50 e das 12 às 12h50 durante o pré-florescimento; e das 7 às 8h50 durante o florescimento. Conseqüentemente, nesses mesmos horários foram verificados os menores consumos de MS e PB para os três estádios fenológicos estudados.The objective of this trial was to evaluate the diurnal ingestive behavior of late pregnant-early lactating Corriedale ewes grazing annual ryegrass (Lolium multiflorum Lam. at different phenological growth stages (vegetative, pre-flowering and flowering. Animals were maintained in paddocks of 1.3 ha from July 21 to November 11 of 2000. Grazing time, bite rate, bite weight, crude protein (CP content per bite, and forage dry matter (DM and CP intakes were measured. The longest grazing time and the greatest forage DM and CP intakes were observed at late afternoon on all three phenological growth stages of annual ryegrass. Grazing time and

  4. Fructan metabolism and changes in fructan composition during cold acclimation in perennial ryegrass

    Science.gov (United States)

    Abeynayake, Shamila W.; Etzerodt, Thomas P.; Jonavičienė, Kristina; Byrne, Stephen; Asp, Torben; Boelt, Birte

    2015-01-01

    Perennial ryegrass (Lolium perenne L.) produces high levels of fructans as a mixture of oligosaccharides and polysaccharides with different degrees of polymerization (DP). The present study describes the analysis of the compositional changes in the full spectrum of fructans, fructan distribution between above ground biomass (top) and the roots, and the transcription of candidate genes involved in fructan metabolism during cold acclimation in perennial ryegrass variety “Veyo” and ecotype “Falster” from distinct geographical origins. We observed changes in fructan composition and induction of low-DP fructans, especially DP = 4, in both the top and the roots of “Veyo” and “Falster” in response to low-temperature stress. The accumulation of DP > 50 fructans was only apparent in the top tissues where the Lp1-FFT expression is higher compared to the roots in both “Veyo” and “Falster.” Our results also show the accumulation and depolymerization of fructans with different DP, together with the induction of genes encoding fructosyltransferases and fructan exohydrolases in both “Veyo” and “Falster” during cold acclimation, supporting the hypothesis that fructan synthesis and depolymerization occurring simultaneously. The ecotype “Falster,” adapted to cold climates, increased total fructan content and produced more DP > 7 fructans in the roots than the variety “Veyo,” adapted to warmer climates. This indicates that high-DP fructan accumulation in roots may be an adaptive trait for plant recovery after abiotic stresses. PMID:26029229

  5. Forage grasses with lower uptake of caesium and strontium could provide 'safer' crops for radiologically contaminated areas.

    Directory of Open Access Journals (Sweden)

    Beth Penrose

    Full Text Available Substitution of a species or cultivar with higher uptake of an element by one with lower uptake has been proposed as a remediation strategy following accidental releases of radioactivity. However, despite the importance of pasture systems for radiological dose, species/cultivar substitution has not been thoroughly investigated for forage grasses. 397 cultivars from four forage grass species; hybrid ryegrass (Lolium perenne L. x Lolium multiflorum Lam., perennial ryegrass (Lolium perenne L., Italian ryegrass (Lolium multiflorum Lam. and tall fescue (Festuca arundinacea Shreb.; were sampled from 19 field-based breeding experiments in Aberystwyth and Edinburgh (UK in spring 2013 and analysed for caesium (Cs and strontium (Sr concentrations. In order to calculate concentration ratios (CRs; the concentration of an element in a plant in relation to the concentration in the soil, soils from the experiments were also analysed to calculate extractable concentrations of Cs and Sr. To test if cultivars have consistently low Cs and Sr concentration ratios, 17 hybrid ryegrass cultivars were sampled from both sites again in summer 2013 and spring and summer 2014. Tall fescue cultivars had lower Cs and Sr CRs than the other species. Three of the selected 17 hybrid ryegrass cultivars had consistently low Cs CRs, two had consistently low Sr CRs and one had consistently low Cs and Sr CRs. Cultivar substitution could reduce Cs CRs by up to 14-fold and Sr CRs by 4-fold in hybrid ryegrass. The identification of species and cultivars with consistently low CRs suggests that species or cultivar substitution could be an effective remediation strategy for contaminated areas.

  6. Comparative Genome Analysis of Lolium-Festuca Complex Species

    DEFF Research Database (Denmark)

    Czaban, Adrian; Byrne, Stephen; Sharma, Sapna

    2015-01-01

    , winter hardiness, drought tolerance and resistance to grazing. In this study we have sequenced and assembled the low copy fraction of the genomes of Lolium westerwoldicum, Lolium multiflorum, Festuca pratensis and Lolium temulentum. We have also generated de-novo transcriptome assemblies for each species......, and these have aided in the annotation of the genomic sequence. Using this data we were able to generate annotated assemblies of the gene rich regions of the four species to complement the already sequenced Lolium perenne genome. Using these gene models we have identified orthologous genes between the species...

  7. Physiological Mechanism of Enhancing Salt Stress Tolerance of Perennial Ryegrass by 24-Epibrassinolide

    Directory of Open Access Journals (Sweden)

    Wenli Wu

    2017-06-01

    Full Text Available Brassinosteroids (BR regulate plant tolerance to salt stress but the mechanisms underlying are not fully understood. This study was to investigate physiological mechanisms of 24-epibrassinolide (EBR's impact on salt stress tolerance in perennial ryegrass (Lolium perenne L. The grass seedlings were treated with EBR at 0, 10, and 100 nM, and subjected to salt stress (250 mM NaCl. The grass irrigated with regular water without EBR served as the control. Salt stress increased leaf electrolyte leakage (EL, malondialdehyde (MDA, and reduced photosynthetic rate (Pn. Exogenous EBR reduced EL and MDA, increased Pn, chlorophyll content, and stomatal conductance (gs. The EBR applications also alleviated decline of superoxide dismutase (SOD and catalase (CAT and ascorbate peroxidase (APX activity when compared to salt treatment alone. Salt stress increased leaf abscisic acid (ABA and gibberellin A4 (GA4 content but reduced indole-3-acetic acid (IAA, zeatin riboside (ZR, isopentenyl adenosine (iPA, and salicylic acid (SA. Exogenous EBR at 10 nm and 100 nM increased ABA, and iPA content under salt stress. The EBR treatment at 100 nM also increased leaf IAA, ZR, JA, and SA. In addition, EBR treatments increased leaf proline and ions (K+, Mg2+, and Ca2+ content, and reduced Na+/K+ in leaf tissues. The results of this study suggest that EBR treatment may improve salt stress tolerance by increasing the level of selected hormones and antioxidant enzyme (SOD and CAT activity, promoting accumulation of proline and ions (K+, Ca2+, and Mg2+ in perennial ryegrass.

  8. Variation in the expression of ergot alkaloids between individual tillers of perennial ryegrass

    Science.gov (United States)

    Mace, Wade; Lunn, Kristy; Lloyd-West, Catherine

    2014-11-01

    Epichloë fungal endophytes of cool season grasses are well known to produce a range of alkaloids of benefit to the host. Some of these compounds are advantageous to agriculture due to qualities that promote pasture persistence (e.g. the loline class of alkaloids confer insect protection) while others are detrimental to the wellbeing of grazing livestock. The ergot alkaloids (e.g. ergovaline), produced in ryegrass and tall fescue associations, causes poor animal health in farming regions in many countries around the world and further study is required to improve our knowledge on this class of compounds. Here we present the application of a quantitative LC-MS/MS (liquid chromatography coupled to mass spectrometry) method measuring eight ergot alkaloids (chanoclavine, agroclavine, elymoclavine, lysergol, lysergic acid, ergine, lysergyl alanine, ergovaline) produced by endophyte infected grasses, to monitor levels in individual tillers from multiple plants of a single cultivar of perennial ryegrass (Lolium perenne cv. ‘Grasslands Samson’) infected with a common toxic endophyte strain (Epichloë festucae var. lolii). Monitoring the expression in individual tillers allows an estimation of the variability within a plant (between tillers) as well as between plants. The study showed that there is significant variation in the concentration of the ergot alkaloids between tillers of a single plant, at or exceeding the level of variation observed between individual plants of a population. This result emphasizes the fundamental importance of robust experimental design and sampling procedures when alkaloid expression assessment is required and these need to be rigorously tailored to the hypothesis being tested.

  9. Variation in the expression of ergot alkaloids between individual tillers of perennial ryegrass

    Directory of Open Access Journals (Sweden)

    Wade Jeffray Mace

    2014-11-01

    Full Text Available Epichloë fungal endophytes of cool season grasses are well known to produce a range of alkaloids of benefit to the host. Some of these compounds are advantageous to agriculture due to qualities that promote pasture persistence (e.g. the loline class of alkaloids confer insect protection while others are detrimental to the wellbeing of grazing livestock. The ergot alkaloids (e.g. ergovaline, produced in ryegrass and tall fescue associations, causes poor animal health in farming regions in many countries around the world and further study is required to improve our knowledge on this class of compounds. Here we present the application of a quantitative LC-MS/MS (liquid chromatography coupled to mass spectrometry method measuring eight ergot alkaloids (chanoclavine, agroclavine, elymoclavine, lysergol, lysergic acid, ergine, lysergyl alanine, ergovaline produced by endophyte infected grasses, to monitor levels in individual tillers from multiple plants of a single cultivar of perennial ryegrass (Lolium perenne cv. ‘Grasslands Samson’ infected with a common toxic endophyte strain (Epichloë festucae var. lolii. Monitoring the expression in individual tillers allows an estimation of the variability within a plant (between tillers as well as between plants.The study showed that there is significant variation in the concentration of the ergot alkaloids between tillers of a single plant, at or exceeding the level of variation observed between individual plants of a population. This result emphasizes the fundamental importance of robust experimental design and sampling procedures when alkaloid expression assessment is required and these need to be rigorously tailored to the hypothesis being tested.

  10. Impact of No-till Cover Cropping of Italian Ryegrass on Above and Below Ground Faunal Communities Inhabiting a Soybean Field with Emphasis on Soybean Cyst Nematodes.

    Science.gov (United States)

    Hooks, Cerruti R R; Wang, Koon-Hui; Meyer, Susan L F; Lekveishvili, Mariam; Hinds, Jermaine; Zobel, Emily; Rosario-Lebron, Armando; Lee-Bullock, Mason

    2011-09-01

    Two field trials were conducted between 2008 and 2010 in Maryland to evaluate the ability of an Italian ryegrass (IR) (Lolium multiflorum) cover crop to reduce populations of plant-parasitic nematodes while enhancing beneficial nematodes, soil mites and arthropods in the foliage of a no-till soybean (Glycine max) planting. Preplant treatments were: 1) previous year soybean stubble (SBS); and 2) herbicide-killed IR cover crop + previous year soybean stubble (referred to as IR). Heterodera glycines population densities were very low and no significant difference in population densities of H. glycines or Pratylenchus spp. were observed between IR and SBS. Planting of IR increased abundance of bacterivorous nematodes in 2009. A reverse trend was observed in 2010 where SBS had higher abundance of bacterivorous nematodes and nematode richness at the end of the cover cropping period. Italian ryegrass also did not affect insect pests on soybean foliage. However, greater populations of spiders were found on soybean foliage in IR treatments during both field trials. Potential causes of these findings are discussed.

  11. Removal and Burial of Weed Seeds by Ants (Hymenoptera: Formicidae) From the Soil Surface of a Cropped Area in Western Australia.

    Science.gov (United States)

    Minkey, D M; Spafford, H

    2016-10-01

    Although granivorous ants are known to collect weed seeds from cropping areas in Australia, the fate of these seeds has not been adequately investigated. Seeds of annual ryegrass (Lolium rigidum Gaud.) and wild radish (Raphanus raphanistrum L.) were placed around the nests of five native ant species (Iridomyrmex greensladei Shattuck, Rhytidoponera metallica Smith, Melophorus turneri Forel, Monomorium rothsteini Forel, and Pheidole hartmeyeri Forel) and tracked continuously over a 24-h period. Removal rates and seed preference of the ant species were evaluated. Ant nests were then excavated to determine the placement of seeds that were taken into each nest. Seed preference, seed removal efficiencies, activity, and seed storage all varied between the ant species. Annual ryegrass seed was collected by three species of ants and was removed from the soil surface more efficiently than wild radish seed. Most ant species stored seed below ground at a depth that is inhibitory to emergence, thereby potentially removing that portion of seed from the seed bank, but some seed was placed at germinable depths. Pheidole hartmeyeri was identified as a likely biological control agent for annual ryegrass seeds and wild radish, while Me. turneri and Mo. rothsteini have potential as biocontrol agents for annual ryegrass, but further research is needed. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Synergistic Effects of Bacillus amyloliquefaciens (GB03 and Water Retaining Agent on Drought Tolerance of Perennial Ryegrass

    Directory of Open Access Journals (Sweden)

    An-Yu Su

    2017-12-01

    Full Text Available Water retaining agent (WRA is widely used for soil erosion control and agricultural water saving. Here, we evaluated the effects of the combination of beneficial soil bacterium Bacillus amyloliquefaciens strain GB03 and WRA (the compound is super absorbent hydrogels on drought tolerance of perennial ryegrass (Lolium perenne L.. Seedlings were subjected to natural drought for maximum 20 days by stopping watering and then rewatered for seven days. Plant survival rate, biomass, photosynthesis, water status and leaf cell membrane integrity were measured. The results showed that under severe drought stress (20-day natural drought, compared to control, GB03, WRA and GB03+WRA all significantly improved shoot fresh weight, dry weight, relative water content (RWC and chlorophyll content and decreased leaf relative electric conductivity (REC and leaf malondialdehyde (MDA content; GB03+WRA significantly enhanced chlorophyll content compared to control and other two treatments. Seven days after rewatering, GB03, WRA and GB03+WRA all significantly enhanced plant survival rate, biomass, RWC and maintained chlorophyll content compared to control; GB03+WRA significantly enhanced plant survival rate, biomass and chlorophyll content compared to control and other two treatments. The results established that GB03 together with water retaining agent promotes ryegrass growth under drought conditions by improving survival rate and maintaining chlorophyll content.

  13. Improving the quality of perennial ryegrass (Lolium perenne L.) for dairy cows by selecting for fast clearing and/or degradable neutral detergent fiber

    NARCIS (Netherlands)

    Taweel, H.Z.; Tas, B.M.; Smit, H.J.; Elgersma, A.; Dijkstra, J.; Tamminga, S.

    2005-01-01

    Neutral detergent fiber (NDF) fractional clearance rate (Kcl) and fractional degradation rate (kd) of six varieties of perennial ryegrass were measured to examine the possibility of selecting for varieties with fast degradable NDF. The experiment was conducted in 2000 and repeated in 2001. In each

  14. Composição botânica e estrutural e valor nutricional de pastagens de azevém consorciadas Botanic and structural composition and nutritional value on intercropped ryegrass pastures

    Directory of Open Access Journals (Sweden)

    Fernando Reimann Skonieski

    2011-03-01

    Full Text Available Neste trabalho objetivou-se avaliar a influência de espécies em consórcio com azevém sobre a composição botânica e estrutural e o valor nutritivo dos pastos em um sistema de transição agroecológica. Foi avaliada a cultura do azevém (Lolium multiflorum Lam. consorciada com aveia-preta (Avena strigosa Schreb., trevo-branco (Trifolium repens L. e amendoim-forrageiro (Arachis pintoi Krapov. & Gregory. O delineamento experimental foi o inteiramente casualizado, com três tratamentos e três repetições. O primeiro pastejo foi realizado 21 dias após a emergência das plantas nas pastagens de azevém + aveia-preta e azevém + amendoim-forrageiro e 28 dias após a emergência na pastagem de azevém + trevo-branco. O segundo pastejo na pastagem de azevém + aveia-preta ocorreu 30 dias após o primeiro pastejo, enquanto nas demais pastagens ocorreu 37 dias depois. As taxas de acúmulo de matéria seca (MS do início do período de exclusão até o pico de produção de MS foram de 77,7; 75,0 e 71,3 kg/ha/dia de MS para as pastagens consorciadas com trevo-branco, amendoim-forrageiro e aveia-preta, respectivamente. A razão folha/colmo até o segundo pastejo foi elevada em todas as pastagens. A redução dos teores de PB conforme os dias de exclusão no pasto de azevém + aveia-preta é menor que nos pastos de azevém consorciado com trevo-branco ou amendoim-forrageiro.The objective of this work was to evaluate the influence of species intercropped with ryegrass on the botanical and structural composition and the nutritional values of pastures in an agroecological transition system. It was evaluated ryegrass (Lolium multiflorum Lam. intercropped with black oats (Avena strigosa Schreb., white clover (Trifolium repens L. and forage peanut (Arachis pintoi Krapov. & Gregory. It was used a complete random design with three treatments and three repetitions. The first grazing was done 21 days after emergence of the plants on the pastures with ryegrass

  15. [Effects of loess soil stabilization on Lolium perenne L. growth and root activity].

    Science.gov (United States)

    Liu, Yue-mei; Zhang, Xing-chang; Wang, Dan-dan

    2011-10-01

    Taking the loess soils with bulk density 1.2 g cm(-3), 1.3 g cm(-3), and 1.4 g cm(-3) from Ansai, Shaanxi Province as test objects, a pot experiment was conducted to study the effects of different amendment amount of soil stabilizer (EN-1 stabilizer) on the growth and root activity of ryegrass (Lolium perenne L.). Within the range of the bulk densities, the leaf chlorophyll content, root activity, root/shoot ratio, root biomass, and plant biomass of L. perenne all decreased with increasing soil bulk density, and were higher under the amendment of EN-1 stabilizer, as compared with the control. With increasing amendment amount of EN-1 stabilizer, the leaf chlorophyll content, root activity, root/shoot ratio, root biomass, and plant biomass had a trend of increased first and decreased then. Soil bulk density and stabilizer amendment amount had significant interactive effect on the root biomass and plant biomass. Overall, the values of the test indices were the highest under 1.3 g cm(-3) soil bulk density and 0.15% EN-1 stabilizer amendment amount.

  16. N transfer in three species grass-clover mixtures with chicory, ribwort plantain or caraway

    DEFF Research Database (Denmark)

    Dhamala, Nawa Raj; Rasmussen, Jim; Carlsson, Georg

    2017-01-01

    Background and aimsThere is substantial evidence that legume-derived Nitrogen (N) is transferred to neighboring non-legumes in grassland mixtures. However, there is sparse information about how deep rooted non-legume forage herbs (forbs) influence N transfer in multi-species grasslands. Methodology......Red clover (Trifolium pretense L.) was grown together with perennial ryegrass (Lolium perenne L.) and one of three forb species: chicory (Cichorium intybus L.), ribwort plantain (Plantago lanceolata L.) or caraway (Carum carvi L.) in a field experiment. During the first year after the establishment, red...... clover leaves were labeled with 15N-urea to determine the N transfer from red clover to companion ryegrass and forbs. ResultsOn an annual basis, up to 15 % of red clover N was transferred to the companion ryegrass and forbs, but predominantly to the grass. The forb species did not differ in their ability...

  17. Effect of rhamnolipids on the uptake of PAHs by ryegrass

    International Nuclear Information System (INIS)

    Zhu Lizhong; Zhang Ming

    2008-01-01

    A hydroponic experiment was conducted to investigate the effect of rhamnolipids, a biosurfactant, on the uptake of polycyclic aromatic hydrocarbons (PAHs) by ryegrass. Results showed that rhamnolipids could enhance the uptake of PAHs by ryegrass roots. With increasing concentration of rhamnolipids, the PAH content in ryegrass roots initially increased and then decreased, while the PAH content in ryegrass shoots did not change. Batch studies also showed that the sorption of phenanthrene by fresh ryegrass roots was dependent on rhamnolipid concentration and showed the same trends as the uptake experiment. The increase of permeability of ryegrass root cells with the increase of rhamnolipid concentration may lead to the initial enhancement of PAH content in ryegrass roots, and the decrease of PAH adsorption onto the root surface with further increase of rhamnolipids led to the decrease of PAH content in ryegrass roots. - Rhamnolipids, a biosurfactant, can promote the uptake of PAHs by ryegrass, which indicates a potential application of surfactant-enhanced phytoremediation

  18. Effect of rhamnolipids on the uptake of PAHs by ryegrass

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Lizhong [Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310028 (China); Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, Zhejiang University, Hangzhou, Zhejiang 310029 (China)], E-mail: zlz@zju.edu.cn; Zhang Ming [Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310028 (China)], E-mail: zhangming@zju.edu.cn

    2008-11-15

    A hydroponic experiment was conducted to investigate the effect of rhamnolipids, a biosurfactant, on the uptake of polycyclic aromatic hydrocarbons (PAHs) by ryegrass. Results showed that rhamnolipids could enhance the uptake of PAHs by ryegrass roots. With increasing concentration of rhamnolipids, the PAH content in ryegrass roots initially increased and then decreased, while the PAH content in ryegrass shoots did not change. Batch studies also showed that the sorption of phenanthrene by fresh ryegrass roots was dependent on rhamnolipid concentration and showed the same trends as the uptake experiment. The increase of permeability of ryegrass root cells with the increase of rhamnolipid concentration may lead to the initial enhancement of PAH content in ryegrass roots, and the decrease of PAH adsorption onto the root surface with further increase of rhamnolipids led to the decrease of PAH content in ryegrass roots. - Rhamnolipids, a biosurfactant, can promote the uptake of PAHs by ryegrass, which indicates a potential application of surfactant-enhanced phytoremediation.

  19. Structure-function analyses of a caffeic acid O-methyltransferase from perennial ryegrass reveal the molecular basis for substrate preference.

    Science.gov (United States)

    Louie, Gordon V; Bowman, Marianne E; Tu, Yi; Mouradov, Aidyn; Spangenberg, German; Noel, Joseph P

    2010-12-01

    Lignin forms from the polymerization of phenylpropanoid-derived building blocks (the monolignols), whose modification through hydroxylation and O-methylation modulates the chemical and physical properties of the lignin polymer. The enzyme caffeic acid O-methyltransferase (COMT) is central to lignin biosynthesis. It is often targeted in attempts to engineer the lignin composition of transgenic plants for improved forage digestibility, pulping efficiency, or utility in biofuel production. Despite intensive investigation, the structural determinants of the regiospecificity and substrate selectivity of COMT remain poorly defined. Reported here are x-ray crystallographic structures of perennial ryegrass (Lolium perenne) COMT (Lp OMT1) in open conformational state, apo- and holoenzyme forms and, most significantly, in a closed conformational state complexed with the products S-adenosyl-L-homocysteine and sinapaldehyde. The product-bound complex reveals the post-methyl-transfer organization of COMT's catalytic groups with reactant molecules and the fully formed phenolic-ligand binding site. The core scaffold of the phenolic ligand forges a hydrogen-bonding network involving the 4-hydroxy group that anchors the aromatic ring and thereby permits only metahydroxyl groups to be positioned for transmethylation. While distal from the site of transmethylation, the propanoid tail substituent governs the kinetic preference of ryegrass COMT for aldehydes over alcohols and acids due to a single hydrogen bond donor for the C9 oxygenated moiety dictating the preference for an aldehyde.

  20. Nitrogen utilization and transformation in red soil fertilized with urea and ryegrass

    International Nuclear Information System (INIS)

    Wu Gang; Zhang Qinzheng; Ye Qingfu; Zhu Zhujun; Xi Haifu; He Zhenli

    1998-01-01

    The influence of fertilization with urea and ryegrass on nitrogen utilization and transformation in red soil has been studied by using 15 N tracer method. When urea and ryegrass were applied alone or in combination, the percentage of N uptaken by ryegrass for labelled urea was 3 and 1.7 times that from labelled ryegrass for the application rate of 200 mgN·kg -1 and 100 mgN·kg -1 , respectively; combining application of ryegrass and urea reduced uptake of urea N and increased uptake of ryegrass N by ryegrass plant, but the percentage of N residue in soil increased for urea and decreased for ryegrass; when urea and ryegrass were applied alone, the percentage of N residue in soil from labelled ryegrass was more than 69% while that from labelled urea was less than 25%, and much more ryegrass N was incorporated into humus than urea N

  1. Behavior pattern of beef heifers supplemented with different energy sources on oat and ryegrass pasture

    Directory of Open Access Journals (Sweden)

    Luiz Angelo Damian Pizzuti

    2012-08-01

    Full Text Available The objective of this study was to evaluate behavior patterns of heifers grazing on black oat (Avena strigosa Schreb. and ryegrass (Lolium multiflorum Lam., fed supplementation with brown rice meal and/or protected fat. A total of 28 Charolais × Nellore crossbred heifers at average initial age of 18 months and with initial live weight of 274.9±4.97 kg were used in the experiment. Animals were kept in oat + ryegrass pastures and distributed in the following treatments: no supplementation; Megalac (MEG: protected fat supplementation; supplementation with brown rice meal (BRM; and supplementation with BRM + MEG. The neutral detergent fiber (NDF intake of pasture either in kg or in percentage of live weight was not changed by supply of supplement, but increased linearly (0.045 kg per day over grazing periods. Supplementation with BRM and BRM + MEG reduced grazing time, 49.63%, in relation to non-supplemented animals and animals supplemented with MEG, 63.13%. Feeding seasons per minute increased over the experimental period with reduction in time spent in each feeding station. The number of bites per feeding station decreased linearly, with a variation of 34.48% in the late grazing period. Heifers supplemented with BRM and BRM + MEG require less time for grazing and increase their idle time, with no modification in displacement patterns within the paddocks and pasture ingestion. Grazing and idle time does not change in the distinct periods of pasture use, but rumination time increases with days of pasture use and with increase in NDF intake.

  2. Effect of different pastures on CLA content in milk and sheep cheese

    Directory of Open Access Journals (Sweden)

    G. Piredda

    2011-03-01

    Full Text Available It is known that milk composition included conjugated linoleic acid (CLA is affected by animal feeding system (Cabiddu et al., 2001. In Sardinia dairy sheep feeding is mainly based on pastures. Most of them are characterised by self-regenerating species, like annual ryegrass (Lolium rigidum Gaudin and burr medic (Medicago polymorpha L.. Non conventional species belonging to the Compositae family such as (Chrysanthemum coronarium L. seem interesting for sheep feeding when other herbages decrease in quality (late spring- early summer...

  3. Enhanced phytoextraction of uranium and selected heavy metals by Indian mustard and ryegrass using biodegradable soil amendments

    Energy Technology Data Exchange (ETDEWEB)

    Duquene, L. [SCK-CEN, Biosphere Impact Studies, Boeretang 200, B-2400 Mol (Belgium); Vandenhove, H. [SCK-CEN, Biosphere Impact Studies, Boeretang 200, B-2400 Mol (Belgium)], E-mail: hvandenh@sckcen.be; Tack, F.; Meers, E. [Ghent University, Laboratory for Analytical Chemistry and Applied Ecochemistry, Coupure Links 653, B-9000 Gent (Belgium); Baeten, J. [Katholieke Hogeschool Kempen, Department of Health-Care and Chemistry, Kleinhoefstraat 4, B-2440 Geel (Belgium); Wannijn, J. [SCK-CEN, Biosphere Impact Studies, Boeretang 200, B-2400 Mol (Belgium)

    2009-02-15

    The applicability of biodegradable amendments in phytoremediation to increase the uptake of uranium (U), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb) and zinc (Zn) by Indian mustard (Brassica juncea) and ryegrass (Lolium perenne) was tested in a greenhouse experiment. Plants were cultivated during one month on two soils with naturally or industrially increased contaminant levels of U. Treatments with citric acid, NH{sub 4}-citrate/citric acid, oxalic acid, S,S-ethylenediamine disuccinic acid (EDDS) or nitrilotriacetic acid (NTA) at a rate of 5 mmol kg{sup -1} dry soil caused increases in soil solution concentrations that were up to 18 times higher for U and up to 1570 times higher for other heavy metals, compared to the controls. Shoot concentrations increased to a much smaller extent. With EDDS, 19-, 34-, and 37-fold increases were achieved in shoots of Indian mustard for U, Pb and Cu, respectively. The increases in plant uptake of Cd, Cr and Zn were limited to a factor of four at most. Ryegrass generally extracted less U and metals than Indian mustard. Despite a marked increase of U and metal concentrations in shoots after addition of amendments, the estimated time required to obtain an acceptable reduction in soil contaminant concentrations was impractically long. Only for Cu and Zn in one of the studied soils, could the Flemish standards for clean soil theoretically be attained in less than 100 years.

  4. Enhanced phytoextraction of uranium and selected heavy metals by Indian mustard and ryegrass using biodegradable soil amendments

    International Nuclear Information System (INIS)

    Duquene, L.; Vandenhove, H.; Tack, F.; Meers, E.; Baeten, J.; Wannijn, J.

    2009-01-01

    The applicability of biodegradable amendments in phytoremediation to increase the uptake of uranium (U), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb) and zinc (Zn) by Indian mustard (Brassica juncea) and ryegrass (Lolium perenne) was tested in a greenhouse experiment. Plants were cultivated during one month on two soils with naturally or industrially increased contaminant levels of U. Treatments with citric acid, NH 4 -citrate/citric acid, oxalic acid, S,S-ethylenediamine disuccinic acid (EDDS) or nitrilotriacetic acid (NTA) at a rate of 5 mmol kg -1 dry soil caused increases in soil solution concentrations that were up to 18 times higher for U and up to 1570 times higher for other heavy metals, compared to the controls. Shoot concentrations increased to a much smaller extent. With EDDS, 19-, 34-, and 37-fold increases were achieved in shoots of Indian mustard for U, Pb and Cu, respectively. The increases in plant uptake of Cd, Cr and Zn were limited to a factor of four at most. Ryegrass generally extracted less U and metals than Indian mustard. Despite a marked increase of U and metal concentrations in shoots after addition of amendments, the estimated time required to obtain an acceptable reduction in soil contaminant concentrations was impractically long. Only for Cu and Zn in one of the studied soils, could the Flemish standards for clean soil theoretically be attained in less than 100 years

  5. Enhanced phytoextraction of uranium and selected heavy metals by Indian mustard and ryegrass using biodegradable soil amendments.

    Science.gov (United States)

    Duquène, L; Vandenhove, H; Tack, F; Meers, E; Baeten, J; Wannijn, J

    2009-02-15

    The applicability of biodegradable amendments in phytoremediation to increase the uptake of uranium (U), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb) and zinc (Zn) by Indian mustard (Brassica juncea) and ryegrass (Lolium perenne) was tested in a greenhouse experiment. Plants were cultivated during one month on two soils with naturally or industrially increased contaminant levels of U. Treatments with citric acid, NH4-citrate/citric acid, oxalic acid, S,S-ethylenediamine disuccinic acid (EDDS) or nitrilotriacetic acid (NTA) at a rate of 5 mmol kg(-1) dry soil caused increases in soil solution concentrations that were up to 18 times higher for U and up to 1570 times higher for other heavy metals, compared to the controls. Shoot concentrations increased to a much smaller extent. With EDDS, 19-, 34-, and 37-fold increases were achieved in shoots of Indian mustard for U, Pb and Cu, respectively. The increases in plant uptake of Cd, Cr and Zn were limited to a factor of four at most. Ryegrass generally extracted less U and metals than Indian mustard. Despite a marked increase of U and metal concentrations in shoots after addition of amendments, the estimated time required to obtain an acceptable reduction in soil contaminant concentrations was impractically long. Only for Cu and Zn in one of the studied soils, could the Flemish standards for clean soil theoretically be attained in less than 100 years.

  6. Desempenho de cordeiras em pastagens de azevém e de milheto sob suplementação Performance of female lambs on Italian ryegrass and pearl millet pastures under supplement levels

    Directory of Open Access Journals (Sweden)

    Denise Adelaide Gomes Elejalde

    2010-04-01

    Full Text Available Avaliou-se o desempenho de cordeiras em pastagens de azevém (Lolium multiflorum Lam. e de milheto (Pennisetum americanum L. Leeke como alimento exclusivo ou com suplementação diária com ração comercial na proporção de 0,5; 1,0 e 1,5% do peso corporal (PC. O método de pastejo utilizado foi o de lotação contínua com taxa de lotação variável. As cordeiras em pastagem de azevém com suplementação nos níveis de 0,5 e 1,5% do PC apresentaram maior ganho médio diário. Independentemente do nível, a suplementação em pastagem de azevém promoveu o maior ganho de peso por área. Na pastagem de milheto, o ganho médio diário, o ganho de peso por área e o escore de condição corporal foram maiores nas cordeiras sob suplementação. A estrutura de pastagens de azevém e de milheto não é influenciada pela oferta de suplemento aos animais. A utilização da pastagem de azevém nos períodos pré e pós-desmama, associada à suplementação nos níveis de 0,5 a 1,5% do peso vivo em pastagem de milheto, permite que cordeiras apresentem peso e escore de condição corporal adequados para o acasalamento aos 9 meses de idade.It was evaluated the performance of female lambs on cultivated pastures of Italian ryegrass (Lolium multiflorum Lam. and pearl millet (Pennisetum americanum (L. Leeke as exclusive food or as daily supplementation with commercial feed at the ratio of 0.5, 1.0 and 1.5% of the body weight. The used grazing method was continuous with variable stocking. Female lambs on Italian ryegrass pasture supplemented with 0.5 and 1.5% of body weight presented greater average daily gain. Regardless to the level, supplementation on Italian ryegrass pasture promoted the highest weight gain per area. In pearl millet pasture, the daily weight gain, the weight gain per area and body condition score were higher for the lambs under supplementation. The structure of Italian ryegrass and pearl millet pastures is not affected by the offer of

  7. Forage seeding in rangelands increases production and prevents weed invasion

    Directory of Open Access Journals (Sweden)

    Josh Davy

    2017-07-01

    Full Text Available Increasing forage productivity in the Sierra foothill rangelands would help sustain the livestock industry as land availability shrinks and lease rates rise, but hardly any studies have been done on forage selections. From 2009 to 2014, in one of the first long-term and replicated studies of seeding Northern California's Mediterranean annual rangeland, we compared the cover of 22 diverse forages to determine their establishment and survivability over time. Among the annual herbs, forage brassica (Brassica napus L. and chicory (Cichorium intybus L. proved viable options. Among the annual grasses, soft brome (Bromus hordeaceus and annual ryegrass (Lolium multiflorum performed well. However, these species will likely require frequent reseeding to maintain dominance. Long-term goals of sustained dominant cover (> 3 years are best achieved with perennial grasses. Perennial grasses that persisted with greater than 50% cover were Berber orchardgrass (Dactylis glomerata, Flecha tall fescue (Lolium arundinaceum and several varieties of hardinggrass (Phalaris aquatica L., Perla koleagrass, Holdfast, Advanced AT. In 2014, these successful perennials produced over three times more dry matter (pounds per acre than the unseeded control and also suppressed annual grasses and yellow starthistle (Centaurea solstitialis L. cover.

  8. Effect of decabromodiphenyl ether (BDE-209) on a soil-biota system: Role of earthworms and ryegrass.

    Science.gov (United States)

    Feng, Mingbao; He, Qun; Shi, Jiaqi; Qin, Li; Zhang, Xuesheng; Sun, Ping; Wang, Zunyao

    2016-06-01

    In the present study, the toxic effect of decabromodiphenyl ether (BDE-209), an important brominated fire retardant, on soil was evaluated by amending with different concentrations (0 mg/kg, 1 mg/kg, 10 mg/kg, and 500 mg/kg dry wt) for 40 d. The activities of 3 soil enzymes (urease, catalase, and alkaline phosphatase) were measured as the principal assessment endpoints. Meanwhile, the effects of natural environmental factors, such as light conditions and soil biota, on BDE-209 intoxication were studied. For the latter, 30 earthworms (Metaphire guillelmi) with fully matured clitella or ryegrass (Lolium perenne) with fully matured leaves were exposed in soil amended with BDE-209. The activities of the soil enzymes were adversely affected by BDE-209, especially for the high-concentration treatments, with greater adverse effects in the dark than in the light. The presence of earthworms reduced toxicity to BDE-209, whereas ryegrass did not. The calculated integrated biomarker response index, which provides a general indicator of the health status of test species by combining different biomarker signals, further validated these findings. Moreover, the antioxidant status (oxidant-antioxidant balance) of these 2 biota was assessed. Results indicated that BDE-209 significantly affected the activities of antioxidant enzymes (superoxide dismutase and catalase) and enhanced the levels of malondialdehyde in both species. The present study may facilitate a better understanding of the toxicity of BDE-209 toward the soil environment. Environ Toxicol Chem 2016;35:1349-1357. © 2015 SETAC. © 2015 SETAC.

  9. Structure-Function Analyses of a Caffeic Acid O-Methyltransferase from Perennial Ryegrass Reveal the Molecular Basis for Substrate Preference[W][OA

    Science.gov (United States)

    Louie, Gordon V.; Bowman, Marianne E.; Tu, Yi; Mouradov, Aidyn; Spangenberg, German; Noel, Joseph P.

    2010-01-01

    Lignin forms from the polymerization of phenylpropanoid-derived building blocks (the monolignols), whose modification through hydroxylation and O-methylation modulates the chemical and physical properties of the lignin polymer. The enzyme caffeic acid O-methyltransferase (COMT) is central to lignin biosynthesis. It is often targeted in attempts to engineer the lignin composition of transgenic plants for improved forage digestibility, pulping efficiency, or utility in biofuel production. Despite intensive investigation, the structural determinants of the regiospecificity and substrate selectivity of COMT remain poorly defined. Reported here are x-ray crystallographic structures of perennial ryegrass (Lolium perenne) COMT (Lp OMT1) in open conformational state, apo- and holoenzyme forms and, most significantly, in a closed conformational state complexed with the products S-adenosyl-l-homocysteine and sinapaldehyde. The product-bound complex reveals the post-methyl-transfer organization of COMT’s catalytic groups with reactant molecules and the fully formed phenolic-ligand binding site. The core scaffold of the phenolic ligand forges a hydrogen-bonding network involving the 4-hydroxy group that anchors the aromatic ring and thereby permits only metahydroxyl groups to be positioned for transmethylation. While distal from the site of transmethylation, the propanoid tail substituent governs the kinetic preference of ryegrass COMT for aldehydes over alcohols and acids due to a single hydrogen bond donor for the C9 oxygenated moiety dictating the preference for an aldehyde. PMID:21177481

  10. Interannual variation in nitrous oxide emissions from perennial ryegrass/white clover grassland used for dairy production.

    Science.gov (United States)

    Burchill, William; Li, Dejun; Lanigan, Gary J; Williams, Micheal; Humphreys, James

    2014-10-01

    Nitrous oxide (N2 O) emissions are subject to intra- and interannual variation due to changes in weather and management. This creates significant uncertainties when quantifying estimates of annual N2 O emissions from grazed grasslands. Despite these uncertainties, the majority of studies are short-term in nature (Nitrous oxide emissions were measured from fertilized and grazed perennial ryegrass/white clover grassland (WC) and from perennial ryegrass plots that were not grazed and did not receive N input (GB), over 4 years from 2008 to 2012 in Ireland (52°51'N, 08°21'W). The annual N2 O-N emissions (kg ha(-1); mean ± SE) ranged from 4.4 ± 0.2 to 34.4 ± 5.5 from WC and from 1.7 ± 0.8 to 6.3 ± 1.2 from GB. Interannual variation in N2 O emissions was attributed to differences in annual rainfall, monthly (December) soil temperatures and variation in N input. Such substantial interannual variation in N2 O emissions highlights the need for long-term studies of emissions from managed pastoral systems. © 2014 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

  11. Effect of energy supplementation on intake and digestion of early ...

    African Journals Online (AJOL)

    Supplementation of early and mid-season Italian ryegrass (Lolium multiflorum cv. Midmar) with maize meal, maize meal with NaHC03 buffer, or maize meal plus combinations of slowly degradable protein was studied. Supplements were administered via a rumen fistula. The effect on intake and digestion of ryegrass was ...

  12. Atlantis Star – a new herbicide in cereals with efficacy against grasses and dicots

    Directory of Open Access Journals (Sweden)

    Kerlen, Dirk

    2016-02-01

    Full Text Available Atlantis Star (mesosulfuron-methyl; iodosulfuron-methyl-sodium; thiencarbazone-methyl; mefenpyr-diethyl is a new cereal herbicide to control blackgrass (Alopecurus myosuroides; sensitive and high infestation, brome grass (Bromus spec., ryegrass (Lolium spec., wild oat (Avena fatua, loose silky-bentgrass (Apera spica-venti L., annual meadow-grass (Poa annua L. and dicot weeds. Atlantis Star can be used in winter wheat, winter triticale, winter rye, winter durum wheat and spelt. The publication is based on efficacy trials from two years of spring application with Atlantis Star.

  13. Determination of microbial protein in perennial ryegrass silage

    NARCIS (Netherlands)

    Driehuis, F.; Wikselaar, van P.G.

    2001-01-01

    The microbial matter fraction was determined in perennial ryegrass silages of different dry-matter (DM) contents, ensiled with or without Lactobacillus plantarum. 15N-Leucine and the bacterial cell wall constituent diaminopimelic acid (DAPA) were used as markers for microbial-N. Perennial ryegrass

  14. Diffusive gradient in thin FILMS (DGT) compared with soil solution and labile uranium fraction for predicting uranium bioavailability to ryegrass.

    Science.gov (United States)

    Duquène, L; Vandenhove, H; Tack, F; Van Hees, M; Wannijn, J

    2010-02-01

    The usefulness of uranium concentration in soil solution or recovered by selective extraction as unequivocal bioavailability indices for uranium uptake by plants is still unclear. The aim of the present study was to test if the uranium concentration measured by the diffusive gradient in thin films (DGT) technique is a relevant substitute for plant uranium availability in comparison to uranium concentration in the soil solution or uranium recovered by ammonium acetate. Ryegrass (Lolium perenne L. var. Melvina) is grown in greenhouse on a range of uranium spiked soils. The DGT-recovered uranium concentration (C(DGT)) was correlated with uranium concentration in the soil solution or with uranium recovered by ammonium acetate extraction. Plant uptake was better predicted by the summed soil solution concentrations of UO(2)(2+), uranyl carbonate complexes and UO(2)PO(4)(-). The DGT technique did not provide significant advantages over conventional methods to predict uranium uptake by plants. Copyright 2009 Elsevier Ltd. All rights reserved.

  15. Diffusive gradient in thin FILMS (DGT) compared with soil solution and labile uranium fraction for predicting uranium bioavailability to ryegrass

    Energy Technology Data Exchange (ETDEWEB)

    Duquene, L. [SCK-CEN, Biosphere Impact Studies, Boeretang 200, B-2400 Mol (Belgium); Vandenhove, H., E-mail: hvandenh@sckcen.b [SCK-CEN, Biosphere Impact Studies, Boeretang 200, B-2400 Mol (Belgium); Tack, F. [Ghent University, Laboratory for Analytical Chemistry and Applied Ecochemistry, Coupure Links 653, B-9000 Gent (Belgium); Van Hees, M.; Wannijn, J. [SCK-CEN, Biosphere Impact Studies, Boeretang 200, B-2400 Mol (Belgium)

    2010-02-15

    The usefulness of uranium concentration in soil solution or recovered by selective extraction as unequivocal bioavailability indices for uranium uptake by plants is still unclear. The aim of the present study was to test if the uranium concentration measured by the diffusive gradient in thin films (DGT) technique is a relevant substitute for plant uranium availability in comparison to uranium concentration in the soil solution or uranium recovered by ammonium acetate. Ryegrass (Lolium perenne L. var. Melvina) is grown in greenhouse on a range of uranium spiked soils. The DGT-recovered uranium concentration (C{sub DGT}) was correlated with uranium concentration in the soil solution or with uranium recovered by ammonium acetate extraction. Plant uptake was better predicted by the summed soil solution concentrations of UO{sub 2}{sup 2+}, uranyl carbonate complexes and UO{sub 2}PO{sub 4}{sup -}. The DGT technique did not provide significant advantages over conventional methods to predict uranium uptake by plants.

  16. Diffusive gradient in thin FILMS (DGT) compared with soil solution and labile uranium fraction for predicting uranium bioavailability to ryegrass

    International Nuclear Information System (INIS)

    Duquene, L.; Vandenhove, H.; Tack, F.; Van Hees, M.; Wannijn, J.

    2010-01-01

    The usefulness of uranium concentration in soil solution or recovered by selective extraction as unequivocal bioavailability indices for uranium uptake by plants is still unclear. The aim of the present study was to test if the uranium concentration measured by the diffusive gradient in thin films (DGT) technique is a relevant substitute for plant uranium availability in comparison to uranium concentration in the soil solution or uranium recovered by ammonium acetate. Ryegrass (Lolium perenne L. var. Melvina) is grown in greenhouse on a range of uranium spiked soils. The DGT-recovered uranium concentration (C DGT ) was correlated with uranium concentration in the soil solution or with uranium recovered by ammonium acetate extraction. Plant uptake was better predicted by the summed soil solution concentrations of UO 2 2+ , uranyl carbonate complexes and UO 2 PO 4 - . The DGT technique did not provide significant advantages over conventional methods to predict uranium uptake by plants.

  17. Rumen degradation characteristics of ryegrass herbage and ryegrass silage are affected by interactions between stage of maturity and nitrogen fertilisation rate

    NARCIS (Netherlands)

    Heeren, J.A.H.; Podesta, S.C.; Hatew, B.; Klop, G.; Laar, van H.; Bannink, A.; Warner, D.; Jonge, de L.H.; Dijkstra, J.

    2014-01-01

    The objective of this experiment was to evaluate interaction effects between stage of maturity and N fertilization rate on rumen degradation characteristics determined with nylon bag incubations of ryegrass herbages and ryegrass silage. Grass herbage (n = 4) was cut after 3 or 5 weeks of regrowth

  18. Expression of alkane monooxygenase (alkB) genes by plant-associated bacteria in the rhizosphere and endosphere of Italian ryegrass (Lolium multiflorum L.) grown in diesel contaminated soil

    International Nuclear Information System (INIS)

    Andria, Verania; Reichenauer, Thomas G.; Sessitsch, Angela

    2009-01-01

    For phytoremediation of organic contaminants, plants have to host an efficiently degrading microflora. To assess the role of endophytes in alkane degradation, Italian ryegrass was grown in sterile soil with 0, 1 or 2% diesel and inoculated either with an alkane degrading bacterial strain originally derived from the rhizosphere of Italian ryegrass or with an endophyte. We studied plant colonization of these strains as well as the abundance and expression of alkane monooxygenase (alkB) genes in the rhizosphere, shoot and root interior. Results showed that the endophyte strain better colonized the plant, particularly the plant interior, and also showed higher expression of alkB genes suggesting a more efficient degradation of the pollutant. Furthermore, plants inoculated with the endophyte were better able to grow in the presence of diesel. The rhizosphere strain colonized primarily the rhizosphere and showed low alkB gene expression in the plant interior. - Bacterial alkane degradation genes are expressed in the rhizosphere and in the plant interior.

  19. Expression of alkane monooxygenase (alkB) genes by plant-associated bacteria in the rhizosphere and endosphere of Italian ryegrass (Lolium multiflorum L.) grown in diesel contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Andria, Verania [AIT Austrian Institute of Technology GmbH, Bioresources Unit, A-2444 Seibersdorf (Austria); Reichenauer, Thomas G. [AIT Austrian Institute of Technology GmbH, Unit of Environmental Resources and Technologies, A-2444 Seibersdorf (Austria); Sessitsch, Angela, E-mail: angela.sessitsch@ait.ac.a [AIT Austrian Institute of Technology GmbH, Bioresources Unit, A-2444 Seibersdorf (Austria)

    2009-12-15

    For phytoremediation of organic contaminants, plants have to host an efficiently degrading microflora. To assess the role of endophytes in alkane degradation, Italian ryegrass was grown in sterile soil with 0, 1 or 2% diesel and inoculated either with an alkane degrading bacterial strain originally derived from the rhizosphere of Italian ryegrass or with an endophyte. We studied plant colonization of these strains as well as the abundance and expression of alkane monooxygenase (alkB) genes in the rhizosphere, shoot and root interior. Results showed that the endophyte strain better colonized the plant, particularly the plant interior, and also showed higher expression of alkB genes suggesting a more efficient degradation of the pollutant. Furthermore, plants inoculated with the endophyte were better able to grow in the presence of diesel. The rhizosphere strain colonized primarily the rhizosphere and showed low alkB gene expression in the plant interior. - Bacterial alkane degradation genes are expressed in the rhizosphere and in the plant interior.

  20. Effect of seed rate and row spacing in seed production of Festulolium

    OpenAIRE

    Deleuran, L.C.; Gislum, R.; Boelt, B.

    2010-01-01

    Establishment methods have proven to be of major importance for grass seed production. The objective of this research was to test the effect of different sowing techniques on plant establishment and the subsequent seed yield. Perennial ryegrass (Lolium perenne L.) is used as the model grass due to its large importance in Danish agriculture. In a three-year trial six different methods of under-sowing of perennial ryegrass in a spring barley cover crop were employed. Perennial ryegrass was e...

  1. Atlantis FLEX (BAY 22010 H – a new herbicide in cereals with efficacy against grasses

    Directory of Open Access Journals (Sweden)

    Kerlen, Dirk

    2014-02-01

    Full Text Available Atlantis FLEX (Mesosulfuron-methyl; Propoxycarbazone-sodium; Mefenpyr-diethyl is a new cereal herbicide to control blackgrass (Alopecurus myosuroides, ryegrass (Lolium spec., brome grass (Bromus spec., wild oat (Avena fatua, loose silky-bentgrass (Apera spica-venti L, annual meadow-grass (Poa annua L. and dicot weeds. Atlantis FLEX can be used in winter wheat, winter triticale, winter rye, winter durum wheat and spelt. The publication is based on efficacy trials from two years of spring application with Atlantis FLEX. It will be shown, that Atlantis FLEX generates a good to excellent efficacy against grass-weeds.

  2. A potential role for endogenous microflora in dormancy release, cytokinin metabolism and the response to fluridone in Lolium rigidum seeds.

    Science.gov (United States)

    Goggin, Danica E; Emery, R J Neil; Kurepin, Leonid V; Powles, Stephen B

    2015-02-01

    Dormancy in Lolium rigidum (annual ryegrass) seeds can be alleviated by warm stratification in the dark or by application of fluridone, an inhibitor of plant abscisic acid (ABA) biosynthesis via phytoene desaturase. However, germination and absolute ABA concentration are not particularly strongly correlated. The aim of this study was to determine if cytokinins of both plant and bacterial origin are involved in mediating dormancy status and in the response to fluridone. Seeds with normal or greatly decreased (by dry heat pre-treatment) bacterial populations were stratified in the light or dark and in the presence or absence of fluridone in order to modify their dormancy status. Germination was assessed and seed cytokinin concentration and composition were measured in embryo-containing or embryo-free seed portions. Seeds lacking bacteria were no longer able to lose dormancy in the dark unless supplied with exogenous gibberellin or fluridone. Although these seeds showed a dramatic switch from active cytokinin free bases to O-glucosylated storage forms, the concentrations of individual cytokinin species were only weakly correlated to dormancy status. However, cytokinins of apparently bacterial origin were affected by fluridone and light treatment of the seeds. It is probable that resident microflora contribute to dormancy status in L. rigidum seeds via a complex interaction between hormones of both plant and bacterial origin. This interaction needs to be taken into account in studies on endogenous seed hormones or the response of seeds to plant growth regulators. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Optimized Use of Low-Depth Genotyping-by-Sequencing for Genomic Prediction Among Multi-Parental Family Pools and Single Plants in Perennial Ryegrass (Lolium perenne L.

    Directory of Open Access Journals (Sweden)

    Fabio Cericola

    2018-03-01

    Full Text Available Ryegrass single plants, bi-parental family pools, and multi-parental family pools are often genotyped, based on allele-frequencies using genotyping-by-sequencing (GBS assays. GBS assays can be performed at low-coverage depth to reduce costs. However, reducing the coverage depth leads to a higher proportion of missing data, and leads to a reduction in accuracy when identifying the allele-frequency at each locus. As a consequence of the latter, genomic relationship matrices (GRMs will be biased. This bias in GRMs affects variance estimates and the accuracy of GBLUP for genomic prediction (GBLUP-GP. We derived equations that describe the bias from low-coverage sequencing as an effect of binomial sampling of sequence reads, and allowed for any ploidy level of the sample considered. This allowed us to combine individual and pool genotypes in one GRM, treating pool-genotypes as a polyploid genotype, equal to the total ploidy-level of the parents of the pool. Using simulated data, we verified the magnitude of the GRM bias at different coverage depths for three different kinds of ryegrass breeding material: individual genotypes from single plants, pool-genotypes from F2 families, and pool-genotypes from synthetic varieties. To better handle missing data, we also tested imputation procedures, which are suited for analyzing allele-frequency genomic data. The relative advantages of the bias-correction and the imputation of missing data were evaluated using real data. We examined a large dataset, including single plants, F2 families, and synthetic varieties genotyped in three GBS assays, each with a different coverage depth, and evaluated them for heading date, crown rust resistance, and seed yield. Cross validations were used to test the accuracy using GBLUP approaches, demonstrating the feasibility of predicting among different breeding material. Bias-corrected GRMs proved to increase predictive accuracies when compared with standard approaches to

  4. Effects of salinity stress on water uptake, germination and early ...

    African Journals Online (AJOL)

    Administrator

    2011-09-07

    Sep 7, 2011 ... Department of Field Crops, Faculty of Agriculture, Namik Kemal University, 59100 Tekirdag, ..... stresses on germination in durum wheat (Triticum durum Desf.) .... transgenic perennial ryegrass (Lolium perenne L.) obtained by.

  5. Effect of application of fertilizer nitrogen, zinc and selenium on zinc nutrition of ryegrass

    International Nuclear Information System (INIS)

    Wei Dongpu; Bai Lingyu; Yao Yunyin; Hua Luo

    2001-01-01

    A pot experiment was carried out to study the effect of zinc or selenium fertilizer applied alone, combined application of nitrogen, zinc and selenium fertilizer on zinc nutrition of ryegrass in mono culture or in mixed culture in mountain yellow-brown earth of Hubei province. The results showed that: 1) Zn content was enhanced by mixed culture (white clover: ryegrass = 1:4), at the same time, Zn content of ryegrass in mixed culture was increased with increasing of Zn fertilizer. 2) The main reason of Zn content of ryegrass decreased in mixed culture was dilution effect due to the increase of dry weight. 3) In mono-Se treatment, Zn content of ryegrass in mixed culture was decreased with increasing of Se fertilizer. 4) In 9 treatment of combined applications of N, Zn and Se fertilizer, treatment of the highest Zn content of ryegrass in mixed culture was N46Zn25Se1; treatment of the highest Zn content of ryegrass in mono culture was N30Zn25Se5

  6. The annual variation in stomatal ammonia compensation point of rye grass (Lolium perenne L.) leaves in an intensively managed grassland

    NARCIS (Netherlands)

    Hove, van L.W.A.; Heeres, P.; Bossen, M.E.

    2002-01-01

    The stomatal ammonia compensation point for ammonia (NH3) of an intensively managed pasture of rye grass (Lolium perenne L.) was followed from mid January till November 2000. Leaf samples were taken every week. Simultaneously, the ambient NH3 concentration was measured. Meteorological data

  7. Seed germination and seedling vigour of italian ryegrass, cocksfoot and timothy following harvest and storage Germinação de sementes e o vigor de plantas jovens de azevem italiano, dactilis e timóteo após a colheita e o armazenamento

    Directory of Open Access Journals (Sweden)

    Rade Stanisavljevic

    2011-12-01

    Full Text Available During post-harvest maturation, different species vary in the length of dormancy breaking or germination increases. Seed dormancy and slow seedling development often limit establishment of forage grass stands. Seed germination and seedling vigour of Italian ryegrass (Lolium italicum A. Braun, Synonym Lolium multiflorum L., cocksfoot (Dactylis glomerata L. and timothy (Phleum pretense L. were observed after harvest and storage. After harvest in June, seeds were stored under standard storage conditions and sampled every 30 days after harvest (DAH, up to 270 DAH, and then every 60 days up to 990 DAH. At each date, seeds were tested for final germination percentage and for seedling vigour traits. Timothy seeds had a maximum germination (88% and the best seedlings vigour at 90 DAH, which implies that early autumn (September-October is the best sowing period for freshly harvested seeds of timothy. Timothy seed germination was poor from 270 DAH (73%. The best germination and vigour of Italian ryegrass and cocksfoot seedlings were between 270 and 330 DAH, which equates to spring sowing time (March-April in the succeeding year. Cocksfoot and Italian ryegrass seeds maintained satisfactory germination levels up to 630 DAH (81% and 810 DAH (81%, respectively. The data can serve for the determination of a proper storage duration management between harvest and sowing of the tested species under ambient conditions of south-eastern Europe.Durante o armazenamento, diferentes espécies comportam-se diferentemente quanto à dormência e crescimento de plântulas. A dormência o desenvolvimento lento das plântulas limitam a época do plantio das gramíneas forrageiras plurianuais. A germinação de sementes e o crescimento das plântulas de azevem italiano (Lolium italicum A. Braun sin. Lolium multiflorum L., Dactilis (Dactilis glomerata L. e de timoteo (Phleum pratense L. foi pesquisada durante a maturação pós-colheita e a silagem. Após a colheita, em junho

  8. Diferentes massas de forragem sobre as variáveis morfogênicas e estruturais de azevém anual Different herbage masses on morphogenetic and structural traits of Italian ryegrass

    Directory of Open Access Journals (Sweden)

    Anna Carolina Cerato Confortin

    2013-03-01

    Full Text Available Características morfogênicas e estruturais de azevém (Lolium multiflorum Lam. foram avaliadas sob pastejo de borregas, em diferentes massas de forragem (MF: "Alta", "Média" e "Baixa", correspondentes a 1800-2000; 1400-1600 e 1000-1200kg ha-1 de matéria seca (MS, respectivamente. O delineamento experimental foi inteiramente casualizado, com três tratamentos e duas repetições de área. O método de pastejo foi de lotação contínua, com número variável de animais. Os dados foram submetidos a análises de correlação e regressão polinomial. A altura do pseudocolmo, o comprimento de lâminas intactas e desfolhadas e o número de folhas em senescência de azevém aumentaram linearmente com a elevação dos valores das massas de forragem. O número de folhas verdes ajustou-se ao modelo de regressão quadrático; o número de folhas em expansão e a densidade populacional de perfilhos não se ajustaram a nenhum modelo de regressão. Em pastagem de azevém, o manejo com massas de forragem dentro da faixa compreendida entre 1.100 e 1.800kg ha-1de MS não provoca alterações nas características morfogênicas dessa gramínea, mas causa diferenças nas características estruturais do dossel. Quando o azevém é manejado com 1.460kg ha-1de MS, seus perfilhos mantêm maior número de folhas verdes e com 1.800kg ha-1 de MS existe maior número de lâminas foliares em senescência e com maior comprimento.Morphogenetic and structural characteristics of Italian ryegrass (Lolium multiflorum Lam., utilized by female lambs and managed with different forage masses (FM were studied. The experimental design was completely randomized, with two area replications and three treatments, consisting of forage masses: "High", "Mean" and "Low", corresponding to 1,800-2,000; 1,400-1,600 and 1,000-1,200kg ha-1 of dry matter (DM, respectively. The grazing method was continuous with variable stocking rate. Data were subjected to correlation analysis and polynomial

  9. The influence of nitrilotriacetate on heavy metal uptake of lettuce and ryegrass

    Energy Technology Data Exchange (ETDEWEB)

    Kulli, B.; Balmer, M.; Krebs, R.; Lothenbach, B.; Geiger, G.; Schulin, R.

    1999-12-01

    Metal uptake and removal from the soil by plants may be a useful measure to remediate contaminated soils. These processes can be enhanced by adding metal chelators to soil. The authors investigated the effect of nitrolotriacetate (NTA) and urea on the uptake of Cd, Cu, and Zn by lettuce (Lactuca sativa L. ev. Orion) and Italian ryegrass (Lolium perenne L. ev. Bastion) in pot experiments. Nitric acid-extractable heavy metal concentrations in the contaminated soil were 2 mg Cd, 530 mg Cu, and 700 mg Zn/kg. Three NTA treatments were compared with two urea treatments, and a control. Nitrilotriacetate and urea increased the NaNO{sub 3}-extractable soil concentrations of the three metals. At the highest NTA dose, metal concentrations in the aboveground plant biomass was 4 to 24 times greater than in the control plants. While NTA increased plant metal concentrations, it reduced plant matter production. At lower doses, this effect was small. At the highest NTA dose, plant growth was almost completely inhibited. Severe visual symptoms indicated metal toxicity as the likely cause. The urea treatments generally increased the plant matter production. Total metal uptake was in general larger at the lowest or at the intermediate NTA dose than at the highest doses. Little additional total metal uptake was achieved with NTA treatments than with urea. Compared with the controls, neither NTA nor urea enhanced total uptake under the given conditions by more than threefold.

  10. Phosphorus availability to ryegrass from urban sewage sludges assessed by isotopic labeling and dilution technique, effect of irradiation

    International Nuclear Information System (INIS)

    El-Motaium, R.A.; Morel, C.

    2007-01-01

    Urban sewage sludge are widely used as alternative P input because of their high P content. Irradiation of sewage sludge is developed in Egypt to make safe spreading of sludge on agricultural fields. Five sludges were sampled from representative urban wastewater treatment plants located in Cairo, Egypt. Sub samples were irradiated using gamma radiation at 6 KGy dose. A pot experiment was conducted under plastic greenhouse using sandy P-deficient soil. The soil was homogeneously labelled with a radioactive solution of carrier-free 32 PO 4 (about 3 MBq kg / soil) to determine the contribution of the different sources of P in plant nutrition. Sludges were applied at 50 mg P/ kg soil. In addition, a control treatment was also carried out to analyze sludge P availability in comparison to a water soluble mineral fertilizer, i.e. 50 mg P/kg soil was applied as commercial monocalcium phosphate (SSP). A reference treatment was included without any P application but the radioactive solution was added. One gram of ryegrass seeds (Lolium multiflorium) was sown in each pot. The aerial parts of the ryegrass were harvested four times, every 3 weeks. Analysis of all harvests included 32 P and total P content was used to determine the respective contribution of soil and sludge to plant P nutrition and the plant available P (L value) using the isotopic dilution principle. The ratio of radioactive P to non-radioactive P, i.e. isotopic composition, was calculated. The total P content in the different urban sewage sludge was ranged from 6.2 to 13.8 g P/ kg and affected by irradiation. Because the soil was extremely P deficient (L value=0.3 mg P/ kg soil), P derived from seeds represented 99% of the P taken up when no P was applied and 87% when applying 50 mg P-SSP/ kg. After correcting the contribution of ryegrass seeds, sludge P contributed by 98% to plant nutrition and 7.2% of the applied P was recovered. The sludge type and irradiation factors did not significantly affect sludge P

  11. Fluorescent in situ hybridization of the ribosomal RNA genes (5S and 35S in the genus Lolium: Lolium canariense, the missing link with Festuca?

    Directory of Open Access Journals (Sweden)

    Inda, Luis A.

    2013-06-01

    Full Text Available Two groups of taxa can be distinguished within the genus Lolium L. based on the pollination system, chromosome size, chromosomal location of nrDNA (5S and 35S (18S-5.8S-26S] and nrDNA phylogeny. The first group includes self-pollinated taxa (L. temulentum, L. persicum and L. remotum, whereas the second group comprises cross-pollinated species (L. perenne, L. multiflorum and L. rigidum. Here we describe that the autogamous species have two 5S sites and four 35S sites in their genome. Two of the 35S sites are present in the chromosomes containing the 5S regions. The allogamous taxa possess two 5S rDNA sites and 6-10 35S sites per genome, depending on the species. Two of these regions (35S may also be present in the chromosomes bearing 5S sites. Our study also demonstrates that Lolium canariense shows a distinctive pattern. It has two 5S and four 35S sites. In this case, the 35S loci are located in different chromosomes than the 5S. This cytogenetic pattern is consistent with that of Festuca pratensis. Thus, despite being allogamous, Lolium canariense does not entirely fit in either of the groups defined for the genus Lolium. The physical mapping of the nrDNA regions in L. canariense is different, and resembles that of F. pratensis, suggesting that this Macaronesian Lolium could be intermediate between Festuca and Lolium.En trabajos previos se ha descrito que el género Lolium L. está formado por dos grupos de taxones basados en el tipo de polinización, tamaño de los cromosomas, localización cromosómica de los loci del ADN ribosómico [5S y 35S (18S-5.8S-26S] y filogenia molecular basada en secuencias de ADN ribosómico. Los dos grupos son: especies autógamas (L. temulentum, L. persicum y L. remotum y especies alógamas (L. perenne, L. multiflorum y L. rigidum. Aquí describimos que según la localización cromosómica de los loci ribosómicos, las especies autógamas tienen dos sitios 5S y cuatro sitios 35S; dos de las cuales coinciden en

  12. Produção de forragem e carga animal de pastagens de Coastcross sobressemeadas com forrageiras de inverno Forage production and stocking rate of Coastcross pastures overseeded with winter grasses

    Directory of Open Access Journals (Sweden)

    Clair Jorge Olivo

    2010-01-01

    Full Text Available O objetivo nesta pesquisa foi avaliar a produção de forragem e a carga animal de quatro pastagens: Coastcross (Cynodon dactylon L. Pers. sobressemeada com azevém (Lolium multiflorum Lam. cv. Comum; Coastcross sobressemeada com azevém e trevo-branco (Trifolium repens L., cv. Yi; azevém e trevo branco; e azevém. O experimento foi realizado no período entre 15 de maio e 24 de outubro de 2006, quando foram realizados cinco ciclos de pastejo. Utilizaram-se vacas da raça Holandesa recebendo concentrado (3,5 kg/dia como suplemento alimentar. Nos períodos pré e pós-pastejo, foram avaliadas a massa de forragem, as composições botânica e estrutural da pastagem e a carga animal. O delineamento experimental foi inteiramente casualizado com quatro tratamentos (pastagens, duas repetições (piquetes e cinco períodos de avaliação (pastejos. Não foram detectadas diferenças entre pastagens para as médias de massa de forragem e carga animal. As pastagens exclusivamente de azevém tiveram maiores produções de lâminas foliares de azevém. As pastagens sobressemeadas apresentaram maior produção de forragem. A sobressemeadura do azevém e do trevo-branco em Coastcross permite estender o período de utilização da pastagem anual e aumenta a produção de forragem.The objective of this research was to evaluate the forage production and stocking rate (SR of four Coastcross (Cynodon dactylon L. Pers. pastures overseeded with ryegrass (Lolium multiflorum Lam. cv. Common; ryegrass plus white clover (Trifolium repens L., cv. Yi over bermudagrass; ryegrass plus white clover and ryegrass. The experiment was carried out from May 15 to October 24, 2006, in five grazing periods. Holstein cows receiving 3.5 kg/daily complementary concentrate feed were used in the evaluation. In the pre and post grazing periods, the forage mass, botanical and structural pasture composition and the stocking rate were assessed. A randomized complete design was used, with

  13. Effects of species diversity on seasonal variation in herbage yield and nutritive value of seven binary grass-legume mixtures and pure grass under cutting

    DEFF Research Database (Denmark)

    Elgersma, Anjo; Søegaard, Karen

    2016-01-01

    Intensively managed sown temperate grasslands are generally of low species diversity, although swards based on grass-legume mixtures may have superior productivity and herbage quality than grass-only swards. We conducted a cutting experiment over two years to test the effect of species composition...... and diversity on herbage yield, contents of N, neutral detergent fibre (NDF) and in vitro organic matter digestibility (IVOMD). Perennial ryegrass (PR, Lolium perenne) was sown alone and with each of four forage legumes: red clover (RC, Trifolium pratense), lucerne (LU, Medicago sativa), birdsfoot trefoil (BT......, Lotus corniculatus) and white clover (WC, Trifolium repens); WC was also sown with hybrid ryegrass (HR, Lolium × boucheanum), meadow fescue (MF, Festuca pratensis) and timothy (TI, Phleum pratense). Herbage productivity was lowest in pure PR followed by PR/BT, and highest in PR/RC; this mixture had...

  14. Stability in chromosome number and DNA content in synthetic tetraploids of Lolium multiflorum after two generations of selection

    Directory of Open Access Journals (Sweden)

    Roselaine Cristina Pereira

    Full Text Available ABSTRACT: Chromosome doubling of Italian ryegrass genotypes ( Lolium multiflorum Lam. adapted to the brazilian edaphoclimatic conditions is an important strategy used by breeders and aims to obtain more vigorous genotypes with better forage quality and disease resistance. The effectiveness of chromosome doubling can be measured by genetic stability and fertility rates of plants over generations. However, a common problem in the polyploidization process is the regeneration of mixoploid plants that have impaired fertility and genetic stability. The objective of this study was to verify if progenies of recently tetraploidized plants remain stable regarding DNA content and chromosome number, over two generations. Progenies of L. multiflorum plants artificially tetraploidized with colchicine treatment were evaluated. Chromosome counting and estimates of the DNA content were used to evaluate the genetic stability. The percentage of tetraploid plants (4X increased over generations (18%, 34% and 91% in cycle 0, 1 and 2, respectively. All progenies identified as tetraploid by flow citometry showed variation in chromosome number (mixoploidy, but produced viable seeds. Results showed that stabilization in chromosome number and DNA content in tetraploidized plant progenies requires time and that the success of this procedure depends on a continuous and accurate screening and selection.

  15. Effect of seed mixture composition and management on competitiveness of herbs in temporary grasslands

    DEFF Research Database (Denmark)

    Mortensen, Tine Bloch; Søegaard, Karen; Eriksen, Jørgen

    2012-01-01

    of perennial ryegrass (Lolium perenne) and white clover (Trifolium repens), 2) cutting frequency, and 3) slurry application. The experiment was carried out over three years. The herb mixture contained salad burnet (Sanguisorba minor), fenugreek (Trigonella foenum-graecum), chicory (Cichcorium intybus), caraway...

  16. Produção e qualidade de forragem da mistura de aveia e azevém sob dois métodos de estabelecimento Forage production and quality of oats and ryegrass mixture under two establishment methods

    Directory of Open Access Journals (Sweden)

    Marta Gomes da Rocha

    2007-02-01

    Full Text Available Neste trabalho, comparou-se a sobre-semeadura de aveia (Avena strigosa Schreb. e azevém (Lolium multiflorum Lam. em pastagem de coastcross (Cynodon dactylon (L. Pers. ao cultivo estreme como métodos de implantação de pastagens de inverno em sistema de pastejo rotacionado com vacas holandesas em lactação. Foram avaliados a produção total de MS (PTF, a massa de forragem de entrada (MFE, o resíduo (RES, as perdas de forragem (PD, a taxa de acúmulo diário de MS (TAD, a carga animal (CA, a oferta de forragem (OF e a biomassa de lâminas foliares (BLF. Para determinação da composição botânica, foram separados em cada espécie (aveia, azevém e coastcross os componentes estruturais folha, colmo e material senescente. Na entrada e saída dos animais da pastagem, foram colhidas amostras por simulação de pastejo para determinação dos teores de PB e FDN. Não houve diferença entre tratamentos para PTF, MFE, RES, PD, TAD, OF e CA. A oferta média de lâminas foliares foi de 1,3±0,67 kg LF/100 kg PV. A sobre-semeadura proporcionou maior biomassa de lâminas foliares disponibilizando forragem com maior teor de PB e menor de FDN na entrada e saída dos animais da pastagem.The oats (Avena strigosa Schreb. and ryegrass (Lolium multiflorum Lam. sodseeding in pasture of coastcross (Cynodon dactylon (L. Pers. was compared to oats and ryegrass in extreme tillage, as establishment methods of winter pastures under rotational stocking with lactating Holstein dairy cows. The total DM production (DMP, pre-grazed herbage mass, residue (RES, forage losses (FL, daily DM accumulation rate (DAR, stocking rate (SR, forage on offer (FO and leaf blade biomass (LBB were evaluated. For botanical composition, oats, ryegrass and coastcross were separated in the structural components: leaves, stems and dead material. Hand plucking samples for CP and NDF determinations were collected during pre- and post-grazing. The DMP, HM, RES, FL, DAR, SR and FO were not

  17. Implementation of genomic prediction in Lolium perenne (L. breeding populations

    Directory of Open Access Journals (Sweden)

    Nastasiya F Grinberg

    2016-02-01

    Full Text Available Perennial ryegrass (Lolium perenne L. is one of the most widely grown forage grasses in temperate agriculture. In order to maintain and increase its usage as forage in livestock agriculture, there is a continued need for improvement in biomass yield, quality, disease resistance and seed yield. Genetic gain for traits such as biomass yield has been relatively modest. This has been attributed to its long breeding cycle, and the necessity to use population based breeding methods. Thanks to recent advances in genotyping techniques there is increasing interest in genomic selection from which genomically estimated breeding values (GEBV are derived. In this paper we compare the classical RRBLUP model with state-of-the-art machine learning (ML techniques that should yield themselves easily to use in GS and demonstrate their application to predicting quantitative traits in a breeding population of L. perenne. Prediction accuracies varied from 0 to 0.59 depending on trait, prediction model and composition of the training population. The BLUP model produced the highest prediction accuracies for most traits and training populations. Forage quality traits had the highest accuracies compared to yield related traits. There appeared to be no clear pattern to the effect of the training population composition on the prediction accuracies. The heritability of the forage quality traits was generally higher than for the yield related traits, and could partly explain the difference in accuracy. Some population structure was evident in the breeding populations, and probably contributed to the varying effects of training population on the predictions. The average linkage disequilibrium (LD between adjacent markers ranged from 0.121 to 0.215. Higher marker density and larger training population closely related with the test population are likely to improve the prediction accuracy.

  18. Inter-simple sequence repeat (ISSR) loci mapping in the genome of perennial ryegrass

    DEFF Research Database (Denmark)

    Pivorienė, O; Pašakinskienė, I; Brazauskas, G

    2008-01-01

    The aim of this study was to identify and characterize new ISSR markers and their loci in the genome of perennial ryegrass. A subsample of the VrnA F2 mapping family of perennial ryegrass comprising 92 individuals was used to develop a linkage map including inter-simple sequence repeat markers...... demonstrated a 70% similarity to the Hordeum vulgare germin gene GerA. Inter-SSR mapping will provide useful information for gene targeting, quantitative trait loci mapping and marker-assisted selection in perennial ryegrass....

  19. Molecular basis of IgE-recognition of Lol p 5, a major allergen of rye-grass pollen.

    Science.gov (United States)

    Suphioglu, C; Blaher, B; Rolland, J M; McCluskey, J; Schäppi, G; Kenrick, J; Singh, M B; Knox, R B

    1998-04-01

    Grass pollen, especially of rye-grass (Lolium perenne). represents an important cause of type I allergy. Identification of IgE-binding (allergenic) epitopes of major grass pollen allergens is essential for understanding the molecular basis of interaction between allergens and human IgE antibodies and therefore facilitates the devising of safer and more effective diagnostic and immunotherapy reagents. The aim of this study was to identify the allergenic epitopes of Lol p 5, a major allergen of rye-grass pollen, immunodissect these epitopes further so that the amino acid residues critical for antibody binding can be determined and investigate the conservation and nature of these epitopes within the context of the natural grass pollen allergens. Peptides, 12-13 amino acid residues long and overlapping each other by 4 amino acid residues, based on the entire deduced amino acid sequence of the coding region of Lol p 5, were synthesised and assayed for IgE-binding. Two strong IgE-binding epitopes (Lol p 5 (49-60) and (265-276), referred to as peptides 7 and 34, respectively) were identified. These epitopes were further resolved by truncated peptides and amino acid replacement studies and the amino acid residues critical for IgE-binding determined (Lol p 5 (49-60) residue Lys57 and (265-276) residue Lys275). Sequences of these epitopes were conserved in related allergens and may form the conserved allergenic domains responsible for the cross-reactivity observed between pollen allergens of taxonomically related grasses. Furthermore, due to its strong IgE-reactivity, synthetic peptide Lol p 5 (265-276) was used to affinity-purify specific IgE antibodies which recognised proteins of other clinically important grass pollens. further indicating presence of allergenic cross-reactivity at the level of allergenic epitope. Moreover, Lol p 5 (265 276) demonstrated a strong capacity to inhibit IgE-binding to natural rye-grass pollen proteins highlighting the antibody accessibility

  20. Phylogenetic relationships in the Festuca-Lolium complex (Loliinae; Poaceae: New insights from chloroplast sequences

    Directory of Open Access Journals (Sweden)

    Yajuan Cheng

    2016-07-01

    Full Text Available The species within the Lolium/Festuca grass complex have dispersed and colonized large areas of temperate global grasslands both naturally and by human intervention. The species within this grass complex represent some of the most important grass species both for amenity and agricultural use worldwide. There has been renewed interest by grass breeders in producing hybrid combinations between these species and several countries now market Festulolium varieties as a combination of genes from both genera. The two genera have been differentiated by their inflorescence structure, but controversy has surrounded the taxonomic classification of the Lolium-Festuca complex species for several decades. In order to better understand the complexities within the Lolium/Festuca complex and their genetic background, the phylogeny of important examplers from the Lolium-Festuca complex were reconstructed. In total 40 taxa representing the Festuca and Lolium species with Vulpia myuros and Brachypodium distachyon as outgroups were sampled, using two noncoding intergenic spacers (trnQ-rps16, trnH-psbA and one coding gene (rbcL. Maximum parsimony (MP, Bayesian inference (BI analyses based on each partition and combined plastid DNA dataset, and median-jointing network analysis were employed. The outcomes strongly suggested that the subgen. Schedonorus has a close relationship to Lolium, and it is also proposed to move the sect. Leucopoa from subgen. Leucopoa to Subgen. Schedonorus and to separate sect. Breviaristatae from the subgen. Leucopoa. We found that F. californica could be a lineage of hybrid origin because of its intermediate placement between the broad-leaved and fine-leaved clade.

  1. Phytoextraction for clean-up of low-level uranium contaminated soil evaluated

    International Nuclear Information System (INIS)

    Vandenhove, H.; Hees, M. van

    2004-01-01

    Spills in the nuclear fuel cycle have led to soil contamination with uranium. In case of small contamination just above release levels, low-cost yet sufficiently efficient remedial measures are recommended. This study was executed to test if low-level U contaminated sandy soil from a nuclear fuel processing site could be phytoextracted in order to attain the required release limits. Two soils were tested: a control soil (317 Bq 238 U kg -1 ) and the same soil washed with bicarbonate (69 Bq 238 U kg -1 ). Ryegrass (Lolium perenne cv. Melvina) and Indian mustard (Brassica juncea cv. Vitasso) were used as test plants. The annual removal of soil activity by the biomass was less than 0.1%. The addition of citric acid (25 mmol kg -1 ) 1 week before the harvest increased U uptake up to 500-fold. With a ryegrass and mustard yield of 15,000 and 10,000 kg ha -1 , respectively, up to 3.5% and 4.6% of the soil activity could be removed annually by the biomass. With a desired activity reduction level of 1.5 and 5 for the bicarbonate-washed and control soil, respectively, it would take 10-50 years to attain the release limit. However, citric acid addition resulted in a decreased dry weight production

  2. Modelling interactions in grass-clover mixtures

    NARCIS (Netherlands)

    Nassiri Mahallati, M.

    1998-01-01

    The study described in this thesis focuses on a quantitative understanding of the complex interactions in binary mixtures of perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.) under cutting. The first part of the study describes the dynamics of growth, production

  3. In situ carbon and nitrogen dynamics in ryegrass-clover mixtures

    DEFF Research Database (Denmark)

    Rasmussen, J.; Eriksen, J.; Jensen, Erik Steen

    2007-01-01

    =9). 15N-enriched compounds were not detected in percolating pore water, which may be caused by either dilution from irrigation or low availability of leachable N compounds. 14C was found solely as 14CO2 in the pore water indicating that dissolved organic carbon (DOC) did not originate from fresh......Carbon (C) and nitrogen (N) dynamics in a third production year ryegrass–clover mixture were investigated in the field. Cylinders (diameter 29.7 cm) were installed to depths of 20, 40 and 60 cm and equipped with suction cups to collect percolating pore water. Ryegrass and clover leaves were cross......-labelled with 14C- and 15N-enriched urea and the fate of the two tracers was studied for 3 months during summer. Transfer of 14C occurred mainly from ryegrass to clover, whereas the largest transfer of 15N was in the opposite direction. The average transfer of N from clover was 40% (SE±3.1, n=9) of N in ryegrass...

  4. Plants modify biological processes to ensure survival following carbon depletion: a Lolium perenne model.

    Directory of Open Access Journals (Sweden)

    Julia M Lee

    Full Text Available BACKGROUND: Plants, due to their immobility, have evolved mechanisms allowing them to adapt to multiple environmental and management conditions. Short-term undesirable conditions (e.g. moisture deficit, cold temperatures generally reduce photosynthetic carbon supply while increasing soluble carbohydrate accumulation. It is not known, however, what strategies plants may use in the long-term to adapt to situations resulting in net carbon depletion (i.e. reduced photosynthetic carbon supply and carbohydrate accumulation. In addition, many transcriptomic experiments have typically been undertaken under laboratory conditions; therefore, long-term acclimation strategies that plants use in natural environments are not well understood. METHODOLOGY/PRINCIPAL FINDINGS: Perennial ryegrass (Lolium perenne L. was used as a model plant to define whether plants adapt to repetitive carbon depletion and to further elucidate their long-term acclimation mechanisms. Transcriptome changes in both lamina and stubble tissues of field-grown plants with depleted carbon reserves were characterised using reverse transcription-quantitative polymerase chain reaction (RT-qPCR. The RT-qPCR data for select key genes indicated that plants reduced fructan degradation, and increased photosynthesis and fructan synthesis capacities following carbon depletion. This acclimatory response was not sufficient to prevent a reduction (P<0.001 in net biomass accumulation, but ensured that the plant survived. CONCLUSIONS: Adaptations of plants with depleted carbon reserves resulted in reduced post-defoliation carbon mobilization and earlier replenishment of carbon reserves, thereby ensuring survival and continued growth. These findings will help pave the way to improve plant biomass production, for either grazing livestock or biofuel purposes.

  5. Planning pastures: taking species attributes to the landscape

    Science.gov (United States)

    Winter hardiness limits the use of the productive forage grass perennial ryegrass (Lolium perenne L.) in the northeastern United States. Both efforts to breed more cold-tolerant varieties and the changing climate increase the potential of this grass in pastures. Growth chamber studies of thirteen co...

  6. Airborne trace element pollution in 11 European cities assessed by exposure of standardised ryegrass cultures

    Science.gov (United States)

    Klumpp, Andreas; Ansel, Wolfgang; Klumpp, Gabriele; Breuer, Jörn; Vergne, Philippe; Sanz, María José; Rasmussen, Stine; Ro-Poulsen, Helge; Ribas Artola, Àngela; Peñuelas, Josep; He, Shang; Garrec, Jean Pierre; Calatayud, Vicent

    Within a European biomonitoring programme, Italian ryegrass ( Lolium multiflorum Lam.) was employed as accumulative bioindicator of airborne trace elements (As, Cd, Cr, Cu, Fe, Ni, Pb, Sb, V, Zn) in urban agglomerations. Applying a highly standardised method, grass cultures were exposed for consecutive periods of four weeks each to ambient air at up to 100 sites in 11 cities during 2000-2002. Results of the 2001 exposure experiments revealed a clear differentiation of trace element pollution within and among local monitoring networks. Pollution was influenced particularly by traffic emissions. Especially Sb, Pb, Cr, Fe, and Cu exhibited a very uneven distribution within the municipal areas with strong accumulation in plants from traffic-exposed sites in the city centres and close to major roads, and moderate to low levels in plants exposed at suburban or rural sites. Accumulation of Ni and V was influenced by other emission sources. The biomonitoring sites located in Spanish city centres featured a much higher pollution load by trace elements than those in other cities of the network, confirming previously reported findings obtained by chemical analyses of dust deposition and aerosols. At some heavily-trafficked sites, legal thresholds for Cu, Pb, and V contents in foodstuff and animal feed were reached or even surpassed. The study confirmed that the standardised grass exposure is a useful and reliable tool to monitor and to assess environmental levels of potentially toxic compounds of particulate matter.

  7. Evaluación agronómica y nutricional del pasto Ryegrass perenne tetraploide (Lolium perenne producido en lecherías de las zonas altas de Costa Rica. I. Producción de biomasa y fenología

    Directory of Open Access Journals (Sweden)

    Luis Villalobos

    2010-01-01

    3090 msnm, provincia de Cartago. La disponibilidad de materia seca pre y pos-pastoreo, el aprovechamiento por hectárea y su porcentaje de utilización promedio para todas las fincas fueron 4110, 2276 y 1833 kg.ha-1 por corte y 44,82%, respectivamente. La edad fenológica y la relación hoja: tallo promedio de las pasturas de ryegrass perenne fueron 2,84 hojas verdes por rebrote, 56:44. Asimismo, la composición promedio de la pradera fue 76,09% ryegrass, 13,76% otras gramíneas (principalmente pasto kikuyo, 6,02% trébol, 1,25% malezas y 2,88% material senescente, respectivamente. La mayor producción de biomasa durante marzo y abril puede conservarse para utilizarse durante las épocas críticas de disponibilidad de forraje o cuando por razones climatológicas se reduce el número de horas efectivas de pastoreo. La evaluación de la edad fenológica en que se pastorea el pasto ryegrass perenne, indica que las fincas en la zona de estudio utilizan esta gramínea en un estado en el que sus reservas de carbohidratos se han recuperado, lo que permite obtener una producción de biomasa y valor nutricional adecuados para satisfacer las necesidades del ganado lechero de la zona.

  8. Efecto de la frecuencia de corte en especies patrenses. (II) Variación del contenido en nitrógeno, fósforo, potasio y azufre de Lolium perenne "V. 807" y Lolium italicum “Tetrone”

    OpenAIRE

    García Criado, Balbino; Duque Macías, Francisco; García Ciudad, Antonia

    2011-01-01

    Se estudia el efecto conjunto de la época de recolección y frecuencia de corte sobre el contenido en nitrógeno, fósforo, potasio y azufre de Lolium perenne V. 807 y Lolium italicum Tetrone. Los cortes se realizan a intervalos de diez, quince, veinte y treinta días en el período de abril a noviembre a 5-10 cm. del suelo. Se considera también la evolución de los elementos con la madurez en cortes mensuales. Los contenidos medios de nitrógeno y fósforo en Lolium perenne y de nitrógeno y azufre e...

  9. Relationship between metal speciation in soil solution and metal adsorption at the root surface of ryegrass.

    Science.gov (United States)

    Kalis, Erwin J J; Temminghoff, Erwin J M; Town, Raewyn M; Unsworth, Emily R; van Riemsdijk, Willem H

    2008-01-01

    The total metal content of the soil or total metal concentration in the soil solution is not always a good indicator for metal availability to plants. Therefore, several speciation techniques have been developed that measure a defined fraction of the total metal concentration in the soil solution. In this study the Donnan Membrane Technique (DMT) was used to measure free metal ion concentrations in CaCl(2) extractions (to mimic the soil solution, and to work under standardized conditions) of 10 different soils, whereas diffusive gradients in thin-films (DGT) and scanning chronopotentiometry (SCP) were used to measure the sum of free and labile metal concentrations in the CaCl(2) extracts. The DGT device was also exposed directly to the (wetted) soil (soil-DGT). The metal concentrations measured with the speciation techniques are related to the metal adsorption at the root surface of ryegrass (Lolium perenne L.), to be able to subsequently predict metal uptake. In most cases the metal adsorption related pH-dependently to the metal concentrations measured by DMT, SCP, and DGT in the CaCl(2) extract. However, the relationship between metal adsorption at the root surface and the metal concentrations measured by the soil-DGT was not-or only slightly-pH dependent. The correlations between metal adsorption at the root surface and metal speciation detected by different speciation techniques allow discussion about rate limiting steps in biouptake and the contribution of metal complexes to metal bioavailability.

  10. MALDI-TOF MS analysis of labile Lolium perenne major allergens in mixes.

    Science.gov (United States)

    Irañeta, S G; Acosta, D M; Duran, R; Apicella, C; Orlando, U D; Seoane, M A; Alonso, A; Duschak, V G

    2008-08-01

    It is well known that allergen extracts used for specific therapy of allergic disorders are commonly stored as mixtures, causing an alteration of its stability. The aim of this report is to identify pollen allergens susceptible to degradation during storage of mixtures containing different sources of proteases in the absence of glycerol as a preserving agent. Mixes containing Lolium perenne (Lol p) pollen extract with either Aspergillus fumigatus or Periplaneta americana extracts were prepared and co-incubated for 90 days at 4 degrees C. Samples were taken off at fixed times and comparatively tested by in vitro and in vivo assays with atopic patients. Selected pollinic allergens were subjected to MALDI-TOF MS analysis. ELISA inhibition evidenced the loss of potency from ryegrass extract, and immunoblotting assays showed the degradation of specific pollinic allergens during storage of mixtures containing protease-rich sources. An in vivo intradermal skin assay confirmed the gradual loss of the biological activity of L. perenne pollen extract co-incubated with non-related protease-rich extracts in comparison with that of the control pollen extract. MALDI-TOF MS analysis allowed us to determine that Lol p 1 and Lol p 5 are susceptible to proteolysis whereas Lol p 4 was found to be resistant to degradation during storage. Lol p 1 and Lol p 5 degradation is responsible for the loss of the biological activity of L. perenne pollen extract when co-incubated with protease-rich fungal and cockroach extracts in the same vial for months in the absence of glycerol as a preserving agent. The integrity of these major allergens must be preserved to increase the vaccine stability and to assure efficacy when mixes are used for immunotherapy.

  11. In vitro and in vivo enhancement of adipogenesis by Italian ryegrass (Lolium multiflorum in 3T3-L1 cells and mice.

    Directory of Open Access Journals (Sweden)

    Mariadhas Valan Arasu

    Full Text Available Adipogenesis is very much important in improving the quality of meat in animals. The aim of the present study was to investigate the in vitro and in vivo adipogenesis regulation properties of Lolium multiflorum on 3T3-L1 pre-adipocytes and mice. Chemical composition of petroleum ether extract of L. multiflorum (PET-LM confirmed the presence of fatty acids, such as α-linolenic acid, docosahexaenoic acid, oleic acid, docosatetraenoic acid, and caprylic acid, as the major compounds. PET-LM treatment increased viability, lipid accumulation, lipolysis, cell cycle progression, and DNA synthesis in the cells. PET-LM treatment also augmented peroxysome proliferator activated receptor (PPAR-γ2, CCAAT/enhancer binding protein-α, adiponectin, adipocyte binding protein, glucose transporter-4, fatty acid synthase, and sterol regulatory element binding protein-1 expression at mRNA and protein levels in differentiated adipocytes. In addition, mice administered with 200 mg/kg body weight PET-LM for 8 weeks showed greater body weight than control mice. These findings suggest that PET-LM facilitates adipogenesis by stimulating PPARγ-mediated signaling cascades in adipocytes which could be useful for quality meat development in animals.

  12. Arbuscular mycorrhizal fungi mediated uptake of 137Cs in leek and ryegrass

    International Nuclear Information System (INIS)

    Rosen, Klas; Weiliang, Zhong; Maertensson, Anna

    2005-01-01

    In a first experiment of soil contaminated with 137 Cs, inoculation with a mixture of arbuscular mycorrhizae enhanced the uptake of 137 Cs by leek under greenhouse conditions, while no effect on the uptake by ryegrass was observed. The mycorrhizal infection frequency in leek was independent of whether the 137 Cs-contaminated soil was inoculated with mycorrhizal spores or not. The lack of mycorrhizae-mediated uptake of 137 Cs in ryegrass could be due to the high root density, which was about four times that of leek, or due to a less well functioning mycorrhizal symbiosis than of leek. In a second experiment, ryegrass was grown for a period of four cuts. Additions of fungi enhanced 137 Cs uptake of all harvests, improved dry weight production in the first cut, and also improved the mycorrhizal infection frequencies in the roots. No differences were obtained between the two fungal inoculums investigated with respect to biomass production or 137 Cs uptake, but root colonization differed. We conclude that, under certain circumstances, mycorrhizae affect plant uptake of 137 Cs. There may be a potential for selecting fungal strains that stimulate 137 Cs accumulation in crops. The use of ryegrass seems to be rather ineffective for remediation of 137 Cs-contaminated soil

  13. Catch crop biomass production, nitrogen uptake and root development under different tillage systems

    DEFF Research Database (Denmark)

    Munkholm, Lars Juhl; Hansen, Elly Møller

    2012-01-01

    tinctoria L.), perennial ryegrass (RG) (Lolium perenne L.) and fodder radish (FR) (Raphanus sativus L.) under three tillage systems. For that, we used a tillage experiment established in 2002 on a Danish sandy loam. The tillage treatments were direct drilling (D), harrowing to 8–10 cm (H) and ploughing (P...

  14. Remediation of lead and cadmium-contaminated soils.

    Science.gov (United States)

    Salama, Ahmed K; Osman, Khaled A; Gouda, Neama Abdel-Razeek

    2016-01-01

    The research was designated to study the ability of plants to bio-accumulate, translocate and remove the heavy metals, lead and cadmium from contaminated soil. The herbal plant ryegrass, Lolium multiflorum was investigated as a bio-accumulator plant for these metals. The translocation of these heavy metals in the herbal plant was compared considering root to shoot transport and redistribution of metals in the root and shoot system. The trace metal contents from root and shoot parts were determined using atomic absorption spectrometer. The results showed that the percent of lead and cadmium transferred to ryegrass plant were averaged as 51.39, and 74.57%, respectively, while those remained in the soil were averaged as 48.61 and 25.43% following 60 days of treatment. The soil-plant transfer index in root and shoot system of ryegrass was found to be 0.32 and 0.20 for lead, and 0.50 and 0.25 for cadmium. These findings indicated that the herbal plant ryegrass, Lolium multiflorum is a good accumulator for cadmium than lead. The soil-plant transfer factor (the conc. of heavy metal in plant to the conc. in soil) indicated that the mechanism of soil remedy using the investigated plant is phytoextraction where the amounts of heavy metals transferred by plant roots into the above ground portions were higher than that remained in the soil. The method offers green technology solution for the contamination problem since it is effective technology with minimal impact on the environment and can be easily used for soil remedy.

  15. Acclimation of the summer annual species, lolium temulentum, to CO(2) enrichment

    Science.gov (United States)

    Lewis; Peratoner; Cairns; Causton; Foyer

    1999-11-01

    Lolium temulentum L. Ba 3081 was grown hydroponically in air (350 &mgr;mol mol(-1) CO(2)) and elevated CO(2) (700 &mgr;mol mol(-1) CO(2)) at two irradiances (150 and 500 &mgr;mol m(-2) s(-1)) for 35 days at which point the plants were harvested. Elevated CO(2) did not modify relative growth rate or biomass at either irradiance. Foliar carbon-to-nitrogen ratios were decreased at elevated CO(2) and plants had a greater number of shorter tillers, particularly at the lower growth irradiance. Both light-limited and light-saturated rates of photosynthesis were stimulated. The amount of ribulose-1, 5-bisphosphate carboxylase-oxygenase (Rubisco) protein was increased at elevated CO(2), but maximum extractable Rubisco activities were not significantly increased. A pronounced decrease in the Rubisco activation state was found with CO(2) enrichment, particularly at the higher growth irradiance. Elevated-CO(2)-induced changes in leaf carbohydrate composition were small in comparison to those caused by changes in irradiance. No CO(2)-dependent effects on fructan biosynthesis were observed. Leaf respiration rates were increased by 68% in plants grown with CO(2) enrichment and low light. We conclude that high CO(2) will only result in increased biomass if total light input favourably increases the photosynthesis-to-respiration ratio. At low irradiances, biomass is more limited by increased rates of respiration than by CO(2)-induced enhancement of photosynthesis.

  16. Effects of catch crop type and root depth on nitrogen leaching and yield of spring barley

    DEFF Research Database (Denmark)

    Sapkota, Tek Bahadur; Askegaard, Margrethe; Lægdsmand, Mette

    2012-01-01

    [chicory (Cichorium intybus L.), fodder radish (Raphanus sativus L.) and perennial ryegrass (Lolium perenne L.)] and their effect on soil mineral N (NO3− and NH4+) in different soil layers by using the FASSET model. The simulated results of catch crop biomass and root growth and mineral N in the soil...

  17. Metabolite profiling during cold acclimation of Lolium perenne genotypes distinct in the level of frost tolerance.

    Science.gov (United States)

    Bocian, Aleksandra; Zwierzykowski, Zbigniew; Rapacz, Marcin; Koczyk, Grzegorz; Ciesiołka, Danuta; Kosmala, Arkadiusz

    2015-11-01

    Abiotic stresses, including low temperature, can significantly reduce plant yielding. The knowledge on the molecular basis of stress tolerance could help to improve its level in species of relatively high importance to agriculture. Unfortunately, the complex research performed so far mainly on model species and also, to some extent, on cereals does not fully cover the demands of other agricultural plants of temperate climate, including forage grasses. Two Lolium perenne (perennial ryegrass) genotypes with contrasting levels of frost tolerance, the high frost tolerant (HFT) and the low frost tolerant (LFT) genotypes, were selected for comparative metabolomic research. The work focused on the analysis of leaf metabolite accumulation before and after seven separate time points of cold acclimation. Gas chromatography-mass spectrometry (GC/MS) was used to identify amino acids (alanine, proline, glycine, glutamic and aspartic acid, serine, lysine and asparagine), carbohydrates (fructose, glucose, sucrose, raffinose and trehalose) and their derivatives (mannitol, sorbitol and inositol) accumulated in leaves in low temperature. The observed differences in the level of frost tolerance between the analysed genotypes could be partially due to the time point of cold acclimation at which the accumulation level of crucial metabolite started to increase. In the HFT genotype, earlier accumulation was observed for proline and asparagine. The increased amounts of alanine, glutamic and aspartic acids, and asparagine during cold acclimation could be involved in the regulation of photosynthesis intensity in L. perenne. Among the analysed carbohydrates, only raffinose revealed a significant association with the acclimation process in this species.

  18. Timing incorporation of different green manure crops to minimize the risk of nitrogen leaching

    Directory of Open Access Journals (Sweden)

    H. KÄNKÄNEN

    2008-12-01

    Full Text Available Seven field trials at four research sites were carried out to study the effect of incorporation time of different plant materials on soil mineral N content during two successive seasons. Annual hairy vetch (Vicia villosa Roth, red clover (Trifolium pratense L., westerwold ryegrass (Lolium multiflorum Lam. var. westerwoldicum and straw residues of N-fertilized spring barley (Hordeum vulgare were incorporated into the soil by ploughing in early September, late October and the following May, and by reduced tillage in May. Delaying incorporation of the green manure crop in autumn lessened the risk of N leaching. The higher the crop N and soil NO3-N content, the greater the risk of leaching. Incorporation in the following spring, which lessened the risk of N leaching as compared with early autumn ploughing, often had an adverse effect on the growth of the succeeding crop. After spring barley, the NO3-N content of the soil tended to be high, but the timing of incorporation did not have a marked effect on soil N. With exceptionally high soil mineral N content, N leaching was best inhibited by growing westerwold ryegrass in the first experimental year. ;

  19. Plastome Sequence Determination and Comparative Analysis for Members of the Lolium-Festuca Grass Species Complex

    OpenAIRE

    Hand, Melanie L.; Spangenberg, German C.; Forster, John W.; Cogan, Noel O. I.

    2013-01-01

    Chloroplast genome sequences are of broad significance in plant biology, due to frequent use in molecular phylogenetics, comparative genomics, population genetics, and genetic modification studies. The present study used a second-generation sequencing approach to determine and assemble the plastid genomes (plastomes) of four representatives from the agriculturally important Lolium-Festuca species complex of pasture grasses (Lolium multiflorum, Festuca pratensis, Festuca altissima, and Festuca...

  20. Co-fermentation of sewage sludge with ryegrass for enhancing hydrogen production: Performance evaluation and kinetic analysis.

    Science.gov (United States)

    Yang, Guang; Wang, Jianlong

    2017-11-01

    The low C/N ratio and low carbohydrate content of sewage sludge limit its application for fermentative hydrogen production. In this study, perennial ryegrass was added as the co-substrate into sludge hydrogen fermentation with different mixing ratios for enhancing hydrogen production. The results showed that the highest hydrogen yield of 60mL/g-volatile solids (VS) added was achieved when sludge/perennial ryegrass ratio was 30:70, which was 5 times higher than that from sole sludge. The highest VS removal of 21.8% was also achieved when sludge/perennial ryegrass ratio was 30:70, whereas VS removal from sole sludge was only 0.7%. Meanwhile, the co-fermentation system simultaneously improved hydrogen production efficiency and organics utilization of ryegrass. Kinetic analysis showed that the Cone model fitted hydrogen evolution better than the modified Gompertz model. Furthermore, hydrogen yield and VS removal increased with the increase of dehydrogenase activity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Arbuscular mycorrhizal fungi mediated uptake of {sup 137}Cs in leek and ryegrass

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, Klas; Weiliang, Zhong; Maertensson, Anna [Department of Soil Sciences, Swedish University of Agricultural Sciences P.O. Box 7014, SE-750 07 Uppsala (Sweden)

    2005-02-15

    In a first experiment of soil contaminated with {sup 137}Cs, inoculation with a mixture of arbuscular mycorrhizae enhanced the uptake of {sup 137}Cs by leek under greenhouse conditions, while no effect on the uptake by ryegrass was observed. The mycorrhizal infection frequency in leek was independent of whether the {sup 137}Cs-contaminated soil was inoculated with mycorrhizal spores or not. The lack of mycorrhizae-mediated uptake of {sup 137}Cs in ryegrass could be due to the high root density, which was about four times that of leek, or due to a less well functioning mycorrhizal symbiosis than of leek. In a second experiment, ryegrass was grown for a period of four cuts. Additions of fungi enhanced {sup 137}Cs uptake of all harvests, improved dry weight production in the first cut, and also improved the mycorrhizal infection frequencies in the roots. No differences were obtained between the two fungal inoculums investigated with respect to biomass production or {sup 137}Cs uptake, but root colonization differed. We conclude that, under certain circumstances, mycorrhizae affect plant uptake of {sup 137}Cs. There may be a potential for selecting fungal strains that stimulate {sup 137}Cs accumulation in crops. The use of ryegrass seems to be rather ineffective for remediation of {sup 137}Cs-contaminated soil.

  2. Feasibility of Pb phytoextraction using nano-materials assisted ryegrass: Results of a one-year field-scale experiment.

    Science.gov (United States)

    Liang, Shu-Xuan; Jin, Yu; Liu, Wei; Li, Xiliang; Shen, Shi-Gang; Ding, Ling

    2017-04-01

    The effect of the combined application of nano-hydroxyapatite (NHAP) or nano-carbon black (NCB) on the phytoextraction of Pb by ryegrass was investigated as an enhanced remediation technique for soils by field-scale experiment. After the addition of 0.2% NHAP or NCB to the soil, temporal variation of the uptake of Pb in aboveground parts and roots were observed. Ryegrass shoot concentrations of Pb were lower with nano-materials application than without nano-materials for the first month. However, the shoot concentrations of Pb were significantly increased with nano-materials application, in particular NHAP groups. The ryegrass root concentrations of Pb were lower with nano-materials application for the first month. These results indicated that nano-materials had significant effects on stabilization of lead, especially at the beginning of the experiment. Along with the experimental proceeding, phytotoxicity was alleviated after the incorporation of nano-materials. The ryegrass biomass was significantly higher with nano-materials application. Consequently, the Pb phytoextraction potential of ryegrass significantly increased with nano-materials application compared to the gounps without nano-materials application. The total removal rates of soil Pb were higher after combined application of NHAP than NCB. NHAP is more suitable than NCB for in-situ remediation of Pb-contaminated soils. The ryegrass translocation factor exhibited a marked increase with time. It was thought that the major role of NHP and NBA might be to alleviate the Pb phytotoxicity and increase biomass of plants. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. De novo assembly of the perennial ryegrass transcriptome using an RNA-Seq strategy.

    Directory of Open Access Journals (Sweden)

    Jacqueline D Farrell

    Full Text Available Perennial ryegrass is a highly heterozygous outbreeding grass species used for turf and forage production. Heterozygosity can affect de-Bruijn graph assembly making de novo transcriptome assembly of species such as perennial ryegrass challenging. Creating a reference transcriptome from a homozygous perennial ryegrass genotype can circumvent the challenge of heterozygosity. The goals of this study were to perform RNA-sequencing on multiple tissues from a highly inbred genotype to develop a reference transcriptome. This was complemented with RNA-sequencing of a highly heterozygous genotype for SNP calling.De novo transcriptome assembly of the inbred genotype created 185,833 transcripts with an average length of 830 base pairs. Within the inbred reference transcriptome 78,560 predicted open reading frames were found of which 24,434 were predicted as complete. Functional annotation found 50,890 transcripts with a BLASTp hit from the Swiss-Prot non-redundant database, 58,941 transcripts with a Pfam protein domain and 1,151 transcripts encoding putative secreted peptides. To evaluate the reference transcriptome we targeted the high-affinity K+ transporter gene family and found multiple orthologs. Using the longest unique open reading frames as the reference sequence, 64,242 single nucleotide polymorphisms were found. One thousand sixty one open reading frames from the inbred genotype contained heterozygous sites, confirming the high degree of homozygosity.Our study has developed an annotated, comprehensive transcriptome reference for perennial ryegrass that can aid in determining genetic variation, expression analysis, genome annotation, and gene mapping.

  4. STUDY ON PHYTO-EXTRACTION BALANCE OF ZN, CD AND PB FROM MINE-WASTE POLLUTED SOILS BY USING FESTUCA ARUNDINACEA AND LOLIUM PERENNE SPECIES

    Directory of Open Access Journals (Sweden)

    B. LIXANDRU

    2009-05-01

    Full Text Available Through the cultivation of tall fescue (Festuca arundinacea and of perennial ryegrass for two years on a chernozem type of soil, in the Banat's plain area we investigated the phyto-extraction potential of Zn, Cd and Pb. In the experimental plot it has been incorporated a quantity of 20 kg of mine-waste per square meter, in a mass ratio of 1:2,5. The mine-waste polluting "contribution" was of 1209 mg Zn / kg d.s., 4.70 mg Cd / kg d.s. and 188.2 mg Pb / kg d.s. The metals content in the soil was determined at the two moments of biomass harvesting, and through balance calculations we could establish the phyto-extraction efficiency of the two foragegrasses species. The obtained results indicate that Festuca arundinacea has an average phyto-extraction yield of 50% for Zn and Cd in the soil; in the case of an ionic excess of 3,5 to 4 times, the phyto-extraction efficiency is reduced, more obvious in the case of Pb (lead ions. The species Lolium perenne registers a yield of almost 92% in the process of phyto-extraction of Zn. The yield values for Cd si Pb are lower, but comparable with the control plot. Unlike Festuca arundinacea, the Lollium perenne species tolerates better the Cd and Pb ionic excess.

  5. Effects of soil microorganisms on uptake of 89Sr by ryegrass and bahia grass

    International Nuclear Information System (INIS)

    Zhong Weiliang; Liu Kexing

    2006-01-01

    In present study, 60 Co γ-rays was used to irradiate soil with doses of 3.0 kGy and 25.0 kGy, respectively, to discriminate between arbuscular mycorrhizal (AM) fungi and other soil microorganisms, while soil without irradiation was used as control to study the effects of soil microorganisms on uptake of 89 Sr by ryegrass and bahia grass. The results showed that the AM infection rates in ryegrass and bahia grass were 48.0% and 28.0% in the control soil, respectively which indicated that both grass species were prone to forming AM symbiosis with AM fungi. Although AM fungi and other soil microorganisms had no significant effect on above ground biomass in ryegrass and bahia grass, both AM fungi and other soil microorganisms decreased the uptake of 89 Sr in the two grass species, though to a more or less extant. (authors)

  6. Natural products phytotoxicity A bioassay suitable for small quantities of slightly water-soluble compounds.

    Science.gov (United States)

    Dornbos, D L; Spencer, G F

    1990-02-01

    A large variety of secondary metabolites that can inhibit germination and/or seedling growth are produced by plants in low quantities. The objective of this study was to develop a bioassay capable of reliably assessing reductions in germination percentage and seedling length of small-seeded plant species caused by exposure to minute quantities of these compounds. The germination and growth of alfalfa (Medicago saliva), annual ryegrass (Lolium multiflorum), and velvetleaf (Abutilon theophrasti) were evaluated against six known phytotoxins from five chemical classes; cinmethylin (a herbicidal cineole derivative) was selected as a comparison standard. Each phytotoxin, dissolved in a suitable organic solvent, was placed on water-agar in small tissue culture wells. After the solvent evaporated, imbibed seeds were placed on the agar; after three days, germination percentages and seedling lengths were measured. Compared to a commonly used filter paper procedure, this modified agar bioassay required smaller quantities of compound per seed for comparable bioassay results. This bioassay also readily permitted the measurement of seedling length, a more sensitive indicator of phytotoxicity than germination. Seedling length decreased sigmoidally as the toxin concentration increased logarithmically. Phytotoxicity was a function of both compound and plant species. Cinmethylin, a grass herbicide, reduced the length of annual ryegrass seedlings by 90-100%, whereas that of alfalfa and velvetleaf was inhibited slightly. The agar bioassay facilitated the rapid and reliable testing of slightly water-soluble compounds, requiring only minute quantities of each compound to give reproducible results.

  7. Genomic prediction in families of perennial ryegrass based on genotyping-by-sequencing

    DEFF Research Database (Denmark)

    Ashraf, Bilal

    In this thesis we investigate the potential for genomic prediction in perennial ryegrass using genotyping-by-sequencing (GBS) data. Association method based on family-based breeding systems was developed, genomic heritabilities, genomic prediction accurancies and effects of some key factors wer...... explored. Results show that low sequencing depth caused underestimation of allele substitution effects in GWAS and overestimation of genomic heritability in prediction studies. Other factors susch as SNP marker density, population structure and size of training population influenced accuracy of genomic...... prediction. Overall, GBS allows for genomic prediction in breeding families of perennial ryegrass and holds good potential to expedite genetic gain and encourage the application of genomic prediction...

  8. Investigate the influence of halloysite and activated carbon mixtures in phytostabilization of Pb-contaminated soil with Lolium perenne L.

    Directory of Open Access Journals (Sweden)

    Radziemska Maja

    2017-06-01

    Full Text Available A pot experiment was conducted to investigate the effects of halloysite and activated carbon mixtures on the biomass and distribution of macronutrients (Mg, K, Ca, Na, P in ryegrass grown in Pb-contaminated soil. The soil was spiked with four different levels of lead contamination, i.e. 0 (control, 200, 400, 800 mg·kg−1 were applied in an analytical grade Pb(NO32 solution mixed thoroughly with the soil. Raw halloysite (3% and activated carbon (1% relative to soil mass mixtures were used to reduce the effect of soil lead contamination. Ryegrass of the Bokser variety was harvested after 42 days, and soil samples were collected for laboratory tests. The mixture of sorbents applied in the experiment which turned out to be most effective at doses of lead amounting to 400 and 800 mg·kg−1 of soil, with the increase in the yield of ryegrass being the highest. Increasing contamination of soil with lead in the series without the mixture of sorbents increased the contents of phosphorus, sodium, calcium and magnesium in ryegrass. The applied mixture of halloysite and activated carbon changed the macronutrient concentration in ryegrass, with the greatest changes found in that of potassium and sodium.

  9. Antioxidant, anti-inflammatory and anti-septic potential of phenolic acids and flavonoid fractions isolated from Lolium multiflorum.

    Science.gov (United States)

    Choi, Ki-Choon; Son, Young-Ok; Hwang, Jung-Min; Kim, Beom-Tae; Chae, Minseon; Lee, Jeong-Chae

    2017-12-01

    Interest has recently renewed in using Lolium multiflorum Lam. (Poaceae) (called Italian ryegrass; IRG) silage as an antioxidant and anti-inflammatory diet. This study investigated the antioxidant, anti-inflammatory and anti-septic potential of IRG silage and identified the primary components in IRG active fractions. Total 16 fractions were separated from the chloroform-soluble extract of IRG aerial part using Sephadex LH-20 column before HPLC analysis. Antioxidant and anti-inflammatory activities of the fractions at doses of 0-100 μg/mL were investigated using various cell-free and cell-mediated assay systems. To explore anti-septic effect of IRG fractions, female ICR and BALB/c mice orally received 40 mg/kg of phenolic acid and flavonoid-rich active fractions F 7 and F 8 every other day for 10 days, respectively, followed by LPS challenge. The active fractions showed greater antioxidant and anti-inflammatory potential compared with other fractions. IC 50 values of F 7 and F 8 to reduce LPS-stimulated NO and TNF-α production were around 15 and 30 μg/mL, respectively. Comparison of retention times with authentic compounds through HPLC analysis revealed the presence of caffeic acid, ferulic acid, myricetin and kaempferol in the fractions as primary components. These fractions inhibited LPS-stimulated MAPK and NF-κB activation. Supplementation with F 7 or F 8 improved the survival rates of mice to 70 and 60%, respectively, in LPS-injected mice and reduced near completely serum TNF-α and IL-6 levels. This study highlights antioxidant, anti-inflammatory and anti-septic activities of IRG active fractions, eventually suggesting their usefulness in preventing oxidative damage and inflammatory disorders.

  10. Remodeling of leaf cellular glycerolipid composition under drought and re-hydration conditions in grasses from the Lolium-Festuca complex

    Directory of Open Access Journals (Sweden)

    Dawid Perlikowski

    2016-07-01

    Full Text Available Drought tolerant plant genotypes are able to maintain stability and integrity of cellular membranes in unfavorable conditions, and to regenerate damaged membranes after stress cessation. The profiling of cellular glycerolipids during drought stress performed on model species such as Arabidopsis thaliana does not fully cover the picture of lipidome in monocots, including grasses. Herein, two closely related introgression genotypes of Lolium multiflorum (Italian ryegrass × Festuca arundinacea (tall fescue were used as a model for other grass species to describe lipid rearrangements during drought and re-hydration. The genotypes differed in their level of photosynthetic capacity during drought, and in their capacity for membrane regeneration after stress cessation. A total of 120 lipids, comprising the classes of monogalactosyldiacyloglycerol, digalactosyldiacyloglycerol, sulfoquinovosyldiacylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, diacylglicerol and triacylglicerol, were analyzed. The results clearly showed that water deficit had a significant impact on lipid metabolism in studied forage grasses. It was revealed that structural and metabolic lipid species changed their abundance during drought and re-watering periods and some crucial genotype-dependent differences were also observed. The introgression genotype characterized by an ability to regenerate membranes after re-hydration demonstrated a higher accumulation level of most chloroplast and numerous extra-chloroplast membrane lipid species at the beginning of drought. Furthermore, this genotype also revealed a significant reduction in the accumulation of most chloroplast lipids after re-hydration, compared with the other introgression genotype without the capacity for membrane regeneration. The potential influence of observed lipidomic alterations on a cellular membrane stability and photosynthetic capacity, are

  11. Toxicities of TNT and RDX to Terrestrial Plants in Five Soils with Contrasting Characteristics

    Science.gov (United States)

    2013-07-01

    lettuce ( Lactuca sativa (L.)) and barley (Hordeum vulgare (L.)), respectively, at analytically determined soil concentrations up to and including 3320... sativa L.), Japanese millet (J. millet; Echinochloa crus-galli L. [Beauv.]), and perennial ryegrass (Lolium perenne L.) in five natural soils that...of the test. The test species in these studies were Medicago sativa (L.) var. Canada no. 1 (alfalfa), Echinochloa crus-galli (L.) P. Beauv. var

  12. The effects of perennial ryegrass and alfalfa on microbial abundance and diversity in petroleum contaminated soil

    International Nuclear Information System (INIS)

    Kirk, Jennifer L.; Klironomos, John N.; Lee, Hung; Trevors, Jack T.

    2005-01-01

    Enhanced rhizosphere degradation uses plants to stimulate the rhizosphere microbial community to degrade organic contaminants. We measured changes in microbial communities caused by the addition of two species of plants in a soil contaminated with 31,000 ppm of total petroleum hydrocarbons. Perennial ryegrass and/or alfalfa increased the number of rhizosphere bacteria in the hydrocarbon-contaminated soil. These plants also increased the number of bacteria capable of petroleum degradation as estimated by the most probable number (MPN) method. Eco-Biolog plates did not detect changes in metabolic diversity between bulk and rhizosphere samples but denaturing gradient gel electrophoresis (DGGE) analysis of PCR-amplified partial 16S rDNA sequences indicated a shift in the bacterial community in the rhizosphere samples. Dice coefficient matrices derived from DGGE profiles showed similarities between the rhizospheres of alfalfa and perennial ryegrass/alfalfa mixture in the contaminated soil at week seven. Perennial ryegrass and perennial ryegrass/alfalfa mixture caused the greatest change in the rhizosphere bacterial community as determined by DGGE analysis. We concluded that plants altered the microbial population; these changes were plant-specific and could contribute to degradation of petroleum hydrocarbons in contaminated soil. - Plant-specific changes in microbial populations on roots affect degradation of petroleum hydrocarbons in contaminated soil

  13. Research note: The use of Lolium multiflorum and uninoculated ...

    African Journals Online (AJOL)

    The δ15 N values for the15 N natural abundance method and atom% 15N values for the 15N dilution method for plant and soil samples are presented. The ryegrass pastures showed the least variation in δ15N and atom%15N values between experimental plots. This crop appeared to be a more appropriate choice in such ...

  14. Development and mapping of DArT markers within the Festuca - Lolium complex

    Science.gov (United States)

    Kopecký, David; Bartoš, Jan; Lukaszewski, Adam J; Baird, James H; Černoch, Vladimír; Kölliker, Roland; Rognli, Odd Arne; Blois, Helene; Caig, Vanessa; Lübberstedt, Thomas; Studer, Bruno; Shaw, Paul; Doležel, Jaroslav; Kilian, Andrzej

    2009-01-01

    Background Grasses are among the most important and widely cultivated plants on Earth. They provide high quality fodder for livestock, are used for turf and amenity purposes, and play a fundamental role in environment protection. Among cultivated grasses, species within the Festuca-Lolium complex predominate, especially in temperate regions. To facilitate high-throughput genome profiling and genetic mapping within the complex, we have developed a Diversity Arrays Technology (DArT) array for five grass species: F. pratensis, F. arundinacea, F. glaucescens, L. perenne and L. multiflorum. Results The DArTFest array contains 7680 probes derived from methyl-filtered genomic representations. In a first marker discovery experiment performed on 40 genotypes from each species (with the exception of F. glaucescens for which only 7 genotypes were used), we identified 3884 polymorphic markers. The number of DArT markers identified in every single genotype varied from 821 to 1852. To test the usefulness of DArTFest array for physical mapping, DArT markers were assigned to each of the seven chromosomes of F. pratensis using single chromosome substitution lines while recombinants of F. pratensis chromosome 3 were used to allocate the markers to seven chromosome bins. Conclusion The resources developed in this project will facilitate the development of genetic maps in Festuca and Lolium, the analysis on genetic diversity, and the monitoring of the genomic constitution of the Festuca × Lolium hybrids. They will also enable marker-assisted selection for multiple traits or for specific genome regions. PMID:19832973

  15. Forward selection for multiple resistance across the non-selective glyphosate, glufosinate and oxyfluorfen herbicides in Lolium weed species.

    Science.gov (United States)

    Fernández, Pablo; Alcántara, Ricardo; Osuna, María D; Vila-Aiub, Martin M; Prado, Rafael De

    2017-05-01

    In the Mediterranean area, Lolium species have evolved resistance to glyphosate after decades of continual use without other alternative chemicals in perennial crops (olive, citrus and vineyards). In recent years, oxyfluorfen alone or mixed with glyphosate and glufosinate has been introduced as a chemical option to control dicot and grass weeds. Dose-response studies confirmed that three glyphosate-resistant Lolium weed species (L. rigidum, L. perenne, L. multiflorum) collected from perennial crops in the Iberian Peninsula have also evolved resistance to glufosinate and oxyfluorfen herbicides, despite their recent introduction. Based on the LD 50 resistance parameter, the resistance factor was similar among Lolium species and ranged from 14- to 21-fold and from ten- to 12-fold for oxyfluorfen and glufosinate respectively. Similarly, about 14-fold resistance to both oxyfluorfen and glufosinate was estimated on average for the three Lolium species when growth reduction (GR 50 ) was assessed. This study identified oxyfluorfen resistance in a grass species for the first time. A major threat to sustainability of perennial crops in the Iberian Peninsula is evident, as multiple resistance to non-selective glyphosate, glufosinate and oxyfluorfen herbicides has evolved in L. rigidum, L. perenne and L. multiflorum weeds. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  16. Identification of companion small grains for Midmar Italian ryegrass ...

    African Journals Online (AJOL)

    Rye was the most successful small grain in being able to fill the winter gap in the fodder flow of Midmar ryegrass. The small grains on average contributed about 25% towards the total DM production in the small grain-Midmar mixtures. Oats, although initially slow, had significantly (P < 0, 05) higher yields than any of the ...

  17. A ¤Terminal Flower-1¤-like gene from perennial ryegrass involved in floral transition and axillary meristem identity

    DEFF Research Database (Denmark)

    Jensen, C.S.; Salchert, K.; Nielsen, K.K.

    2001-01-01

    12 weeks to induce flowering. During this period a decrease in LpTFL1 message was detected in the ryegrass apex. However, upon subsequent induction with elevated temperatures and long-day photoperiods, LpTFL1 message levels increased and reached a maximum M:hen the ryegrass apex has formed visible...

  18. Comportamento ingestivo de novilhas de corte submetidas a estratégias de suplementação em pastagens de aveia e azevém Ingestive behavior of beef heifers submitted to strategies of supplementation on oats and ryegrass pastures

    Directory of Open Access Journals (Sweden)

    Carolina Bremm

    2008-07-01

    Full Text Available Avaliou-se o comportamento ingestivo de novilhas de corte recebendo suplemento em pastagem de aveia preta (Avena strigosa Schreb. e azevém (Lolium multiflorum Lam. sob lotação contínua. Como tratamentos, foram avaliadas quatro estratégias de suplementação: sem suplemento - animais em pastagem de aveia (AV e azevém (AZ; crescente - animais em pastagem de AV e AZ recebendo níveis crescentes de suplemento (0,3; 0,6 e 0,9% do peso vivo -PV; fixo - animais em pastagem de AV e AZ recebendo nível fixo de suplemento (0,9% PV; e decrescente - animais em pastagem de AV e AZ recebendo níveis decrescentes (1,5; 1,2 e 0,9% do PV de suplemento. As características estruturais (massa de forragem, massa de forragem verde, oferta de forragem, oferta de lâminas foliares verdes, relação folha:colmo, proporção de lâminas foliares e colmos + bainhas de aveia e proporção de lâminas foliares e colmos + bainhas de azevém e bromatológicas (proteína bruta, digestibilidade in vitro da matéria orgânica, nutrientes digestíveis totais e fibra em detergente neutro do pasto foram semelhantes entre as estratégias de suplementação, mas variaram conforme os períodos de utilização do pasto. Os tempos diários de pastejo, ruminação e ócio e de permanência no cocho (min/dia e a massa de bocado (g MO/boc diferiram entre as estratégias de suplementação e as características do pasto no decorrer do ciclo. A taxa de bocado/minuto foi influenciada apenas pelo ciclo do pasto.It was evaluated the ingestive behavior of beef heifers on black oats (Avena strigosa Schreb. and Italian ryegrass (Lolium multiflorum Lam. pastures under different strategies of supplementation and continuous stocking system. The treatments evaluated were: 'no supplement'- animals on black oats (BO and Italian ryegrass (IR pasture; 'increasing' - animals on BO and IR pasture receiving increasing levels (0.3, 0.6, and 0.9% of live weight - LW of supplement; 'fixed' - animals on

  19. Contribution of a phytotoxic compound to the allelopathy of Ginkgo biloba.

    Science.gov (United States)

    Kato-Noguchi, Hisashi; Takeshita, Sayaka

    2013-11-01

    Ginkgo (Ginkgo biloba L.) has not changed over 121 million years. There may be unknown special strategy for the survival. Gingko litter inhibited the growth of weed species ryegrass (Lolium multiflorum L.). The inhibition was greater with the litter of the close position than that of the far position from the gingko tree. A phytotoxic substance, 2-hydroxy-6-(10-hydroxypentadec-11-enyl)benzoic acid (HHPEBA) was isolated in the litter. HHPEBA concentration was greater in the litter of the close position than that of the far position from the tree. HHPEBA inhibited the ryegrass growth at concentrations greater than 3 μM. HHPEBA was estimated to be able to cause 47-62% of the observed growth inhibition of ryegrass by the gingko litter. Therefore, HHPEBA may contribute to the inhibitory effect caused by ginkgo litter and may provide a competitive advantage for gingko to survive through the growth inhibition of the neighboring plants.

  20. Development and mapping of DArT markers within the Festuca - Lolium complex

    Directory of Open Access Journals (Sweden)

    Studer Bruno

    2009-10-01

    Full Text Available Abstract Background Grasses are among the most important and widely cultivated plants on Earth. They provide high quality fodder for livestock, are used for turf and amenity purposes, and play a fundamental role in environment protection. Among cultivated grasses, species within the Festuca-Lolium complex predominate, especially in temperate regions. To facilitate high-throughput genome profiling and genetic mapping within the complex, we have developed a Diversity Arrays Technology (DArT array for five grass species: F. pratensis, F. arundinacea, F. glaucescens, L. perenne and L. multiflorum. Results The DArTFest array contains 7680 probes derived from methyl-filtered genomic representations. In a first marker discovery experiment performed on 40 genotypes from each species (with the exception of F. glaucescens for which only 7 genotypes were used, we identified 3884 polymorphic markers. The number of DArT markers identified in every single genotype varied from 821 to 1852. To test the usefulness of DArTFest array for physical mapping, DArT markers were assigned to each of the seven chromosomes of F. pratensis using single chromosome substitution lines while recombinants of F. pratensis chromosome 3 were used to allocate the markers to seven chromosome bins. Conclusion The resources developed in this project will facilitate the development of genetic maps in Festuca and Lolium, the analysis on genetic diversity, and the monitoring of the genomic constitution of the Festuca × Lolium hybrids. They will also enable marker-assisted selection for multiple traits or for specific genome regions.

  1. Effects of ewes grazing sulla or ryegrass pasture for different daily durations on forage intake, milk production and fatty acid composition of cheese.

    Science.gov (United States)

    Bonanno, A; Di Grigoli, A; Mazza, F; De Pasquale, C; Giosuè, C; Vitale, F; Alabiso, M

    2016-12-01

    Sulla (Sulla coronarium L.) forage is valued for its positive impact on ruminant production, in part due to its moderate content of condensed tannin (CT). The duration of daily grazing is a factor affecting the feed intake and milk production of ewes. In this study, the effects of grazing sulla pasture compared with annual ryegrass, and the extension of grazing from 8 to 22 h/day, were evaluated with regard to ewe forage intake and milk production, as well as the physicochemical properties and fatty acid (FA) composition of cheese. During 42 days in the spring, 28 ewes of the Comisana breed were divided into four groups (S8, S22, R8 and R22) that grazed sulla (S) or ryegrass (R) for 8 (0800 to 1600 h) or 22 h/day, and received no feeding supplement. In six cheese-making sessions, cheeses were manufactured from the 48 h bulk milk of each group. Compared with ewes grazing ryegrass, those grazing sulla had higher dry matter (DM) intake, intake rate and milk yield, and produced milk that was lower in fat and higher in casein. Ewes grazing for 22 h spent more time eating, which reduced the intake rate, increased DM and nutrient intake and milk yield, and reduced milk fat. Due to the ability of CT to inhibit the complete ruminal biohydrogenation of polyunsaturated fatty acids (PUFA), the FA composition of sulla cheese was more beneficial for consumer health compared with ryegrass cheese, having lower levels of saturated fatty acids and higher levels of PUFA and n-3 FA. The FA profile of S8 cheese was better than that of S22 cheese, as it was higher in branched-chain FA, monounsaturated FA, PUFA, rumenic acid (c9,t11-C18:2), and had a greater health-promoting index. The effect of short grazing time on sulla was attributed to major inhibition of PUFA biohydrogenating ruminal bacteria, presumably stimulated by the higher accumulation of sulla CT in the rumen, which is related to a higher intake rate over a shorter eating time. Thus, grazing sulla improved the performance of

  2. Effect of aflatoxin B1 on in vitro ruminal fermentation of rations high in alfalfa hay or ryegrass hay

    DEFF Research Database (Denmark)

    Jiang, Y H; Yang, H J; Lund, Peter

    2012-01-01

    A 2 × 4 factorial experiment was conducted to determine the effect of aflatoxin B1 (AFB1) at dose rates of 0, 320, 640, 960 ng/ml on ruminal fermentation of substrates high in alfalfa hay (HA, alfalfa hay: maize meal = 4:1) and ryegrass hay (HR, ryegrass hay: maize meal = 4:1). In vitro dry matter...

  3. Comparative transcriptome analysis within the Lolium/Festuca species complex reveals high sequence conservation

    DEFF Research Database (Denmark)

    Czaban, Adrian; Sharma, Sapna; Byrne, Stephen

    2015-01-01

    species from the Lolium-Festuca complex, ranging from 52,166 to 72,133 transcripts per assembly. We have also predicted a set of proteins and validated it with a high-confidence protein database from three closely related species (H. vulgare, B. distachyon and O. sativa). We have obtained gene family...... clusters for the four species using OrthoMCL and analyzed their inferred phylogenetic relationships. Our results indicate that VRN2 is a candidate gene for differentiating vernalization and non-vernalization types in the Lolium-Festuca complex. Grouping of the gene families based on their BLAST identity...... enabled us to divide ortholog groups into those that are very conserved and those that are more evolutionarily relaxed. The ratio of the non-synonumous to synonymous substitutions enabled us to pinpoint protein sequences evolving in response to positive selection. These proteins may explain some...

  4. Genetic differences in root mass of Lolium perenne varieties under field conditions

    NARCIS (Netherlands)

    Deru, J.G.C.; Schilder, H.; Schoot, van der J.R.; Eekeren, van N.J.M.

    2014-01-01

    Although grasses have dense rooting systems, nutrient uptake and productivity can be increased, and N-leaching reduced, if rooting is further improved. The variation in root mass of 16 varieties of Lolium perenne was studied under field conditions in two experiments on sandy soil in The Netherlands.

  5. Ingestive behavior and displacement patterns of beef heifers on Italian ryegrass pasture Comportamento ingestivo e padrões de deslocamento de bezerras de corte em pastagem de azevém

    Directory of Open Access Journals (Sweden)

    Carine Lisete Glienke

    2010-02-01

    Full Text Available The effect of supplementation on ingestive behavior and displacement patterns of beef heifers grazing on Italian ryegrass (Lolium multiflorum Lam. pasture was evaluated. The grazing method was continuous with variable stocking rate. The experimental design was completely randomized with repeated measures on time. The supplement utilized was a commercial ration (17% CP, 21.4% NDF, daily supplied at 2 pm, in the proportion of 1% of body weight. The evaluations were made through visual observations, in four continuous periods of 24 hours. There was no difference in the bite rate between heifers with and without supplement and bite rate was higher at the end of the period of pasture utilization. Supplemented animals increased bite mass. The number of stations/minute, bites/station and the displacement patterns was influenced by forage changes along the occupation period. The ingestive behavior and displacement patterns of heifers are modified by supplementation and structural variation of the grass along its biological cycle. In the reproductive stage of Italian ryegrass, grazing time, daily number of bites and, feeding stations and time for station are similar between not supplemented and supplemented heifers.Avaliou-se a influência da suplementação no comportamento ingestivo e nos padrões de deslocamento de bezerras de corte em pastagem exclusiva de azevém (Lolium multiflorum Lam.. Utilizou-se o método de pastejo com lotação contínua e número variável de animais, em delineamento inteiramente casualizado, com medidas repetidas no tempo. Os animais receberam ração comercial (17% PB, 21,4% FDN na proporção de 1% do PV, fornecida diariamente às 14 h. As avaliações foram feitas por meio de observação visual, em quatro períodos contínuos de 24 horas. A taxa de bocados não diferiu entre bezerras com e sem suplementação, mas foi maior no período final de utilização da pastagem. Animais sob suplementação realizaram bocados

  6. Assessing genetic diversity of perennial ryegrass ( Lolium perenne L ...

    African Journals Online (AJOL)

    In this study, inter-simple sequence repeat (ISSR) markers were used to compare genetic diversity between commercial cultivars and natural germplasm which were obtained from Europe, Africa, Asia, and North America. There was a relatively high genetic variation in the whole collection judged by the polymorphism rate ...

  7. A comparison of ltalian ryegrass (Lolium multillorum) cultivars Bxalta ...

    African Journals Online (AJOL)

    Cell wall content was more often lower for Exalta than for Midmar, the dif- ference being ... intestine cannot be increased if the N-energy ratio in the plant is improved. ... sition are not different, animal performance should benefit. In the present ...

  8. Meiotic behaviour of individual chromosomes of Festuca pratensis in tetraploid Lolium multiflorum

    Czech Academy of Sciences Publication Activity Database

    Kopecký, David; Lukaszewski, A.J.; Doležel, Jaroslav

    2008-01-01

    Roč. 16, č. 7 (2008), s. 987-998 ISSN 0967-3849 R&D Projects: GA ČR GP521/07/P479 Institutional research plan: CEZ:AV0Z50380511 Keywords : Chromosome pairing * Festuca * Lolium Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.405, year: 2008

  9. Transfer of radiocaesium to barley, rye grass and pea

    International Nuclear Information System (INIS)

    Oehlenschlaeger, M.; Gissel-Nielsen, G.

    1989-11-01

    In areas with intensive farming, as in Denmark, it is of great interest to identify possible countermeasures to be taken in order to reduce the longterm effects of radioactive contamination of arable land. The most important longer-lived radionuclides from the Chernobyl were 137 Cs and 134 Cs. The aim of the present project was to identify crops with relatively low or high root uptake of these two isotopes. Although such differences may be small, a shift in varieties might be a cost-effective way to reduce collective doses. The experiment was carried out at Risoe National Laboratory in the summer of 1988. The species used were: spring barley (Hordeum vulgare L) varieties: Golf, Apex, Anker, Sila; Perennial rye grass (Lolium perenne L.) varieties: Darbo (early) and Patoro (late); Italian rye-grass (Lolium multiflorum) variety: Prego; and pea (Pisum arvense L.) variety: Bodil. Each crop was grown in two types of soil, a clay-loam and an organic soil. 137 Cs was added to the clay-loam. The organic soil, which was contaminated with 137 Cs from the Chernobyl accident, was supplied with 134 Cs. Sila barley and Italian rye-grass were identified among the species tested as plants with a relative high uptake of radio-caesium. (author)

  10. Perennial ryegrass for dairy cows: Intake, milk production and nitrogen utilization

    NARCIS (Netherlands)

    Tas, B.M.

    2005-01-01

    Keywords: perennial ryegrass, dairy cows, intake, digestibility milk production, nitrogen utilisation.In the Netherlands, grass is one of the main roughages in the diet of high productive dairy cows. Grass is associated with two main problems: the limited dry matter intake (DMI)

  11. Forage mass and stocking rate of elephant grass pastures managed under agroecological and conventional systems

    OpenAIRE

    Clair Jorge Olivo; Carlos Alberto Agnolin; Priscila Flôres Aguirre; Cláudia Marques de Bem; Tiago Luís da Ros de Araújo; Michelle Schalemberg Diehl; Gilmar Roberto Meinerz

    2014-01-01

    The objective was to evaluate elephant grass (Pennisetum purpureum Schum.) pastures, under the agroecological and conventional systems, as forage mass and stocking rate. In the agroecological system, the elephant grass was established in rows spaced by 3.0 m from each other. During the cool season ryegrass (Lolium multiflorum Lam.) was established between these rows, which allowed the development of spontaneous growth species during the warm season. In the conventional system the elephant gra...

  12. Study on Effect of alfalfa, ryegrass and wheat middlings contents in ...

    African Journals Online (AJOL)

    微软用户

    2013-03-13

    Mar 13, 2013 ... 3Poultry Institute, Chinese Academy of Agricultural Sciences, Yangzhou, People's Republic of China. Accepted 16 ... The body weight (BW) of Group 3 geese was the biggest ... of alfalfa, ryegrass and wheat bran in diet in geese was 18%. .... images of tissues were taken using a Nikon Optiphot microscope.

  13. Cultivar effects of perennial ryegrass on herbage intake by grazing dairy cows

    NARCIS (Netherlands)

    Smit, H.J.

    2006-01-01

    Perennial ryegrass is the most abundant grass species in temperate climates. An increased herbage intake of dairy cows by breeding new cultivars could have a large potential impact on agriculture. The effects of cultivars on sward structure, nutritive value, physical characteristics and disease

  14. Using Massive Multivariate NIRS Data in Ryegrass

    DEFF Research Database (Denmark)

    Edriss, Vahid; Greve-Pedersen, Morten; Jensen, Christian S

    2015-01-01

    Near infrared spectroscopy (NIRS) analytical techniques is a simple, fast and low cost method of high dimensional phenotyping compared to usual chemical techniques. To use this method there is no need for special sample preparation. The aim of this study is to use NIRS data to predict plant traits...... (e.g. dry matter, protein content, etc.) for the next generation. In total 1984 NIRS data from 995 ryegrass families (first cut) were used. The Absorption of radiation in the region of 960 – 1690 nm in every 2 nm distance produced 366 bins to represent the NIRS spectrum. The amount of genetic...

  15. Does introduction of clover in an agricultural grassland affect the food base and functional diversity of Collembola?

    DEFF Research Database (Denmark)

    D'Annibale, Alessandra; Sechi, Valentina; Larsen, Thomas

    2017-01-01

    plots with either perennial ryegrass (Lolium perenne L.), whiteclover (Trifolium repens L.) or a mixture of both in a Danish agricultural grassland 6 and 14 months after establishing the leys (September and May, respectively). Diet preferences were investigated via stable isotope analyses (SIA...... in the white clover than ryegrass plots. Changes in taxa specific density and traits distribution as a response to the C:N ratio of plant material, suggest that plant material quality was the main factor affecting the collembolan community,especially when comparing the two sampling occasions. Functional...... richness decreased under conditions of low quality material. In contrast to our hypothesis, population densities did not increase under mixture treatment and functional richness decreased. Our results suggest that habitat changes, via different plant composition, can affect some functional groups, having...

  16. Effects of humic acid and competing cations on metal uptake by Lolium perenne

    NARCIS (Netherlands)

    Kalis, E.J.J.; Temminghoff, E.J.M.; Weng, L.P.; Riemsdijk, van W.H.

    2006-01-01

    Within the biotic ligand model, which describes relationships between chemical speciation and metal binding at an organism's surface, multicomponent (long-term) metal uptake by plants has seldom been studied. In the present work, we exposed perennial ryegrass to nutrient solutions with two levels of

  17. Can inter-cultivar variation in caesium and strontium uptake reduce contamination of forage grasses? - Can inter-cultivar variation in caesium and strontium accumulation by forage grasses be used to reduce contamination of cows' milk in radiologically contaminated areas?

    Energy Technology Data Exchange (ETDEWEB)

    Penrose, B. [NERC Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Lancaster, LA1 4AP (United Kingdom); School of Biosciences, University of Nottingham, Sutton Bonington Campus, Leicestershire, LE12 5RD (United Kingdom); Beresford, N. [NERC Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Lancaster, LA1 4AP (United Kingdom); Broadley, M.; Crout, N.M.J.; King, J.; Young, S. [School of Biosciences, University of Nottingham, Sutton Bonington Campus, Leicestershire, LE12 5RD (United Kingdom); Lovatt, A. [Institute of Biological, Environmental and Rural Sciences (IBERS), Aberystwyth University, Gogerddan, Aberystwyth, Ceredigion, SY23 3E E (United Kingdom); Thomson, R. [Science and Advice for Scottish Agriculture (SASA), Roddinglaw Road, Edinburgh, EH12 9FJ (United Kingdom)

    2014-07-01

    Radiocaesium and radiostrontium primarily enter the food chain via plant root uptake, including indirectly via animal fodders. Inter-species variation in caesium and strontium accumulation in plants has previously been reported to be over two orders of magnitude. This variation could be exploited to select crops with relatively low uptake to reduce transfer of these radionuclides to consumers in contaminated areas. Exploiting intra-species (i.e. inter-cultivar) variation in caesium and strontium uptake has not yet been evaluated as a remediation strategy as sufficient data have not been available. As cows' milk has been one of the main contributors to human dose following the Chernobyl and Mayak accidents, we have chosen to focus on elucidating the extent and nature of inter-cultivar variation in caesium and strontium uptake in forage grasses. A total of 412 cultivars from four species of forage grass; perennial ryegrass (Lolium perenne; 284 cultivars), Italian ryegrass (Lolium multiflorum; 17 cultivars), hybrid ryegrass (Lolium hybridum; 101 cultivars) and tall fescue (Festuca arundinacea; 10 cultivars) were sampled from 20 sets of experimental plots in Aberystwyth (Wales, UK) and Edinburgh (Scotland, UK). Fifty-nine cultivars were grown in both locations. At least three replicates of the same cultivar were grown in each set of plots. Vegetation samples from 2208 plots were collected both in spring 2013 (May-June) and summer 2013 (August-September). The samples were oven-dried and milled then analysed for elemental composition using inductively coupled plasma mass spectrometry (ICP-MS). Stable caesium and strontium were measured as a proxy measurement for radiocaesium and radiostrontium concentrations. Concentrations of chemical analogues of caesium and strontium (potassium and calcium) and a number of other elements were measured. Soil samples from the experimental plots were also collected, dried, milled and analysed using ICP-MS. This paper will present

  18. Association of Candidate Genes With Submergence Response in Perennial Ryegrass

    Directory of Open Access Journals (Sweden)

    Xicheng Wang

    2017-05-01

    Full Text Available Perennial ryegrass is a popular cool-season grass species due to its high quality for forage and turf. The objective of this study was to identify associations of candidate genes with growth and physiological traits to submergence stress and recovery after de-submergence in a global collection of 94 perennial ryegrass accessions. Accessions varied largely in leaf color, plant height (HT, leaf fresh weight (LFW, leaf dry weight (LDW, and chlorophyll fluorescence (Fv/Fm at 7 days of submergence and in HT, LFW and LDW at 7 days of recovery in two experiments. Among 26 candidate genes tested by various models, single nucleotide polymorphisms (SNPs in 10 genes showed significant associations with traits including 16 associations for control, 10 for submergence, and 8 for recovery. Under submergence, Lp1-SST encoding sucrose:sucrose 1-fructosyltransferase and LpGA20ox encoding gibberellin 20-oxidase were associated with LFW and LDW, and LpACO1 encoding 1-aminocyclopropane-1-carboxylic acid oxidase was associated with LFW. Associations between Lp1-SST and HT, Lp6G-FFT encoding fructan:fructan 6G-fructosyltransferase and Fv/Fm, LpCAT encoding catalase and HT were also detected under submergence stress. Upon de-submergence, Lp1-SST, Lp6G-FFT, and LpPIP1 encoding plasma membrane intrinsic protein type 1 were associated with LFW or LDW, while LpCBF1b encoding C-repeat binding factor were associated with HT. Nine significant SNPs in Lp1-SST, Lp6G-FFT, LpCAT, and LpACO1 resulted in amino acid changes with five substitutions found in Lp1-SST under submergence or recovery. The results indicated that allelic diversity in genes involved in carbohydrate and antioxidant metabolism, ethylene and gibberellin biosynthesis, and transcript factor could contribute to growth variations in perennial ryegrass under submergence stress and recovery after de-submergence.

  19. Water erosion in surface soil conditions: runoff velocity, concentration and D50 index of sediments in runoff

    OpenAIRE

    Ramos,Júlio César; Bertol,Ildegardis; Barbosa,Fabrício Tondello; Bertól,Camilo; Mafra,Álvaro Luiz; Miquelluti,David José; Mecabô Júnior,José

    2016-01-01

    ABSTRACT Water erosion and contamination of water resources are influenced by concentration and diameter of sediments in runoff. This study aimed to quantify runoff velocity and concentration and the D50 index of sediments in runoff under different soil surface managements, in the following treatments: i) cropped systems: no-tilled soil covered by ryegrass (Lolium multiflorum Lam.) residue, with high soil cover and minimal roughness (HCR); no tilled soil covered by vetch (Vicia sativa L.) res...

  20. Postharvest residues from grass seed crops for bioenergy

    OpenAIRE

    Simić, Aleksandar; Čolić, Vladislava; Vučković, Savo; Dželetović, Željko; Bijelić, Zorica; Mandić, Violeta

    2016-01-01

    During grass seed production, a large amount of low forage quality biomass has been produced. Tall growing perennial grasses such as tall fescue (Festuca arundinacea L.) and Italian ryegrass (Lolium multiflorum Lam.) can be used as an alternative source for bioenergy production as they can be grown in less cultivated areas, their residues in seed production could be valuable energy source and can be potentially used as a dual purpose crop (bioenergy and forage). In this research, potentials o...

  1. Effect of Repeated Application of Manure on Herbage Yield, Quality and Wintering Ability during Cropping of Dwarf Napiergrass with Italian Ryegrass in Hilly Southern Kyushu, Japan

    Directory of Open Access Journals (Sweden)

    Renny Fatmyah Utamy

    2018-03-01

    Full Text Available The effects of two levels of manure application (184 and 275 kg N ha−1 year−1 on herbage yield, quality, and wintering ability during the cropping of a dwarf genotype of late-heading (DL Napiergrass (Pennisetum purpureum Schumach oversown with Italian ryegrass (IR; Lolium multiflorum Lam. were examined and compared with chemical fertilizer application (234 kg N ha−1 year−1 for 4 years to determine a sustainable and environmentally harmonized herbage production in a hilly area (340 m above sea level. No significant (p > 0.05 differences in growth attributes of plant height, tiller density, percentage of leaf blade, or dry matter yield appeared in either DL Napiergrass or IR among moderate levels (184–275 kg N ha−1 year−1 of manure and chemical fertilizer treatments. IR exhibited no significant detrimental effect on spring regrowth of DL Napiergrass, which showed a high wintering ability in all treatments. In vitro dry matter digestibility of DL Napiergrass tended to increase with increasing manure application, especially at the first defoliation in the first three years. Manure application improved soil chemical properties and total nitrogen and carbon content. The results suggested that the lower rate of manure application of 184 kg nitrogen ha−1 year−1 would be suitable, which would be a good substitute for chemical fertilizer application with an equilibrium nitrogen budget for sustainable DL Napiergrass and IR cropping in the hilly region of southern Kyushu.

  2. Effect of influent aeration on removal of organic matter from coffee processing wastewater in constructed wetlands.

    Science.gov (United States)

    Rossmann, Maike; Matos, Antonio Teixeira; Abreu, Edgar Carneiro; Silva, Fabyano Fonseca; Borges, Alisson Carraro

    2013-10-15

    The aim of the present study was to evaluate the influence of aeration and vegetation on the removal of organic matter in coffee processing wastewater (CPW) treated in 4 constructed wetlands (CWs), characterized as follows: (i) ryegrass (Lolium multiflorum) cultivated system operating with an aerated influent; (ii) non-cultivated system operating with an aerated influent, (iii) ryegrass cultivated system operating with a non-aerated influent; and (iv) non-cultivated system operating with a non-aerated influent. The lowest average chemical oxygen demand (COD), biochemical oxygen demand (BOD) and total suspended solids (TSS) removal efficiencies of 87, 84 and 73%, respectively, were obtained in the ryegrass cultivated system operating with a non-aerated influent. However, ryegrass cultivation did not influence the removal efficiency of organic matter. Artificial aeration of the CPW, prior to its injection in the CW, did not improve the removal efficiencies of organic matter. On other hand it did contribute to increase the instantaneous rate at which the maximum COD removal efficiency was reached. Although aeration did not result in greater organic matter removal efficiencies, it is important to consider the benefits of aeration on the removal of the other compounds. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Persistence of Overseeded Cool-Season Grasses in Bermudagrass Turf

    OpenAIRE

    Thomas Serensits; Matthew Cutulle; Jeffrey F. Derr

    2011-01-01

    Cool-season grass species are commonly overseeded into bermudagrass turf for winter color. When the overseeded grass persists beyond the spring; however, it becomes a weed. The ability of perennial ryegrass, Italian (annual) ryegrass, intermediate ryegrass, and hybrid bluegrass to persist in bermudagrass one year after seeding was determined. Perennial ryegrass, intermediate ryegrass, and Italian ryegrass produced acceptable ground cover in the spring after fall seeding. Hybrid bluegrass di...

  4. Development and mapping of DArT markers within the Festuca-Lolium complex

    Czech Academy of Sciences Publication Activity Database

    Kopecký, David; Bartoš, Jan; Lukaszewski, A.; Baird, J. H.; Černoch, V.; Koelliker, R.; Rognli, O. A.; Blois, H.; Caig, V.; Luebberstedt, T.; Studer, B.; Shaw, P.; Doležel, Jaroslav; Kilian, A.

    2009-01-01

    Roč. 10, Art_No_473 (2009), s. 1-11 ISSN 1471-2164 R&D Projects: GA MZe QH71267; GA ČR GP521/07/P479 Institutional research plan: CEZ:AV0Z50380511 Keywords : DIVERSITY ARRAYS TECHNOLOGY * GENETIC-LINKAGE MAP * PERENNIAL RYEGRASS Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.759, year: 2009

  5. Leaching of indaziflam applied at two rates under different rainfall situations in Florida Candler soil.

    Science.gov (United States)

    Jhala, Amit J; Ramirez, Analiza H M; Singh, Megh

    2012-03-01

    Indaziflam {N-[(1R, 2S)-2,3-dihydro-2,6-dimethyl-1H-inden-1-yl]-6-[(1RS)-1fluoroethyl]-1,3,5-triazine-2,4-diamine} is a new pre-emergence herbicide recently registered for a broad spectrum weed control in Florida citrus. Experiments were conducted to evaluate leaching of indaziflam applied at 73 and 145 g ai ha(-1) in Florida Candler soil under simulated rainfall of 5, 10, and 15 cm ha(-1). Indaziflam leached the least (12.6 ± 0.6 cm) when applied at 73 g ai ha(-1) under 5 cm ha(-1) rainfall. Indaziflam leached furthest (30.2 ± 0.9 cm) when applied at 145 g ai ha(-1) under 15 cm ha(-1) rainfall. The visual control ratings of a bio-indicator species ryegrass (Lolium multiflorum L.) was 97% at 15 cm ha(-1) rainfall when indaziflam applied at 145 g ai ha(-1) in the 26 to 30 cm horizon indicating the maximum movement and activity of indaziflam. A dose response experiment was conducted to determine the sensitivity of ryegrass to various doses of indaziflam that confirmed that application of indaziflam at 29.20 g ai ha(-1) was sufficient to prevent germination of ryegrass. There was no mortality of ryegrass plants beyond the 30 cm and the biomass of ryegrass was comparable with untreated control indicating that indaziflam did not leach beyond this distance even under 15 cm ha(-1) rainfall.

  6. Studies of phosphorus-containing fertilizer uptake in soils by 32P isotope labelling

    International Nuclear Information System (INIS)

    Fueleky, Gyoergy; Osztoics, Andrasne; Papne Kranitz, Erzsebet

    1983-01-01

    Breeding experiments were carried out with rye-grass (Lolium perenne L.) on two soil types to determine the plant uptake of phosphorus from naturally occuring element and from that added to the soil by superphosphate fertilizers. 32 P isotope labelling and radiometric measuring method were applied. In addition to the determination of phosphorus uptake, the phosphorus contents of the soil from its natural stock and from the fertilizer for both soil types can be determined by this method. (A.L.)

  7. Do green manures as winter cover crops impact the weediness and crop yield in an organic crop rotation?

    OpenAIRE

    Madsen, Helena; Talgre, Liina; Eremeev, Viacheslav; Alaru, Maarika; Kauer, Karin; Luik, Anne

    2016-01-01

    The effects of different winter cover crops and their combination with composted cattle manure on weeds and crop yields were investigated within a five-field crop rotation (barley undersown with red clover, red clover, winter wheat, pea, potato) in three organic cropping systems. The control system (Org 0) followed the rotation. In organic systems Org I and Org II the winter cover crops were used as follows: ryegrass (Lolium perenne L. in 2011/2012) and a mixture of winter oilseed-rape (Brass...

  8. A synteny-based draft genome sequence of the forage grass Lolium perenne

    DEFF Research Database (Denmark)

    Byrne, Stephen; Nagy, Istvan; Pfeifer, Matthias

    2015-01-01

    -family of the grass family (Poaceae). Transcriptome data was used to identify 28 455 gene models, and we utilized macro-co-linearity between perennial ryegrass and barley, and synteny within the grass family, to establish a synteny-based linear gene order. The gametophytic self-incompatibility mechanism enables...

  9. Development and mapping of a public reference set of SSR markers in Lolium perenne L.

    NARCIS (Netherlands)

    Bach, J.L.; Muylle, H.; Arens, P.F.P.; Andersen, C.H.; Bach Holm, P.; Ghesquiere, M.; Julier, B.; Lubberstedt, T.; Nielsen, K.K.; Riek, de J.; Roldán-Ruiz, I.; Roulund, N.; Taylor, C.; Vosman, B.J.; Barre, P.

    2005-01-01

    We report on the characterization and mapping of 76 simple sequence repeat (SSR) markers for Lolium perenne. These markers are publicly available or obtained either from genomic libraries enriched for SSR motifs or L. perenne expressed sequence tag (EST) clones. Four L. perenne mapping populations

  10. Desempenho animal em pasto de aveia e azevém com distintas biomassas de lâminas foliares Animal performance in oat and Italian ryegrass pastures under leaf lamina biomass levels

    Directory of Open Access Journals (Sweden)

    Duilio Guerra Bandinelli

    2005-12-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de biomassas de lâminas foliares no desempenho animal. Utilizou-se mistura de aveia (Avena strigosa Schreb e azevém (Lolium multiflorum Lam., para determinar quantidades adequadas de sua biomassa no manejo da pastagem. Foram realizados dois experimentos, na estação fria de 2002 e 2003. Na avaliação de 2002, os valores de biomassa de lâminas foliares foram de 360 kg ha-1 (baixa e 630 kg ha-1 (alta. Em 2003, foram obtidas biomassas de 352, 422 e 507 kg ha-1, classificadas como baixa, média e alta, respectivamente. O método de pastejo foi contínuo, com taxa de lotação variada; os animais utilizados foram terneiros da raça Charolês e cruzados com Nelore, com idade inicial de nove meses. As variáveis de produção animal avaliadas, nos dois anos, foram: ganho médio diário, carga animal e ganho de peso vivo por área. As distintas biomassas de lâminas foliares mantidas não são fatores limitantes ao desempenho animal.The objective of this work was to evaluate the effect of different leaf lamina biomass over animal performance. A mixture of oat (Avena strigosa Schreb and Italian ryegrass (Lolium multiflorum Lam. was used to determine adequate levels of leaf lamina biomass for pasture management. Two trials were made, in 2002 and 2003 cool seasons. In 2002 evaluation, leaf lamina biomass values were of 360 kg ha-1 (low and 630 kg ha-1 (high. In 2003, values obtained for leaf lamina biomasses were of 352, 422 and 507 kg ha-1, being classified as low, medium and high, respectively. Grazing method was continuous, with variable stocking rate; testing animals were calves of Charolais breed and its crosses with Nelore breed, with initial age of nine months. Evaluated variables in animal production, in both years, were: average daily gain, stocking rate and live weight gain per area. Leaf lamina biomasses evaluated are not limiting factors to animal performance.

  11. Regulation of levels of serum antibodies to ryegrass pollen allergen Lol pIV by an internal image anti-idiotypic monoclonal antibody.

    Science.gov (United States)

    Zhou, E M; Kisil, F T

    1995-03-01

    A murine monoclonal anti-idiotypic antibody (anti-Id), designated B1/1, was produced against an idiotope of a murine antibody (mAb91), which recognizes the epitope, site A, of allergen Lol pIV, one of the major groups of allergens in ryegrass (Lolium perenne) pollen. The ability of B1/1 to modulate the antibody responses to Lol pIV was investigated in murine model systems. In the first system, B1/1-keyhole limpet haemocyanin (KLH) conjugate was administered to treat three different strains of mice (C57BL/6, BALB/c and C3H). In the second and third model systems, a solution of B1/1 in phosphate-buffered saline (PBS) was used to treat syngeneic BALB/c mice at various doses and time intervals, respectively. The treatment with either form of B1/1, administered at doses ranging from 100 ng to 100 micrograms mouse, resulted in a reduction of the levels of the antibodies to Lol pIV. In particular, the level of IgE antibodies to Lol pIV was greatly reduced. The administration of a single intravenous (i.v.) injection of a solution of B1/1 8 weeks prior to the challenge with Lol pIV was still effective in reducing the level of antibodies to the allergen. Moreover, the level of antibodies to Lol pIV that expressed the idiotope mAb91 was also markedly decreased. By contrast, it was observed that the level of antibodies to Lol pIV in mice pretreated with B1/1 in PBS at a dose of 10 ng/mouse increased (albeit slightly) compared to that in mice treated with control mAb. These experimental models lend themselves for investigating the mechanism(s) by which an anti-Id modulates antibody responses to a grass pollen allergen.

  12. Effective rumen degradation of dry matter, crude protein and neutral detergent fibre in forage determined by near infrared reflectance spectroscopy

    DEFF Research Database (Denmark)

    Ohlsson, C; Houmøller, L P; Weisbjerg, Martin Riis

    2007-01-01

    The objective of the present study was to examine if near infrared reflectance spectroscopy (NIRS) could be used to predict degradation parameters and effective degradation from scans of original forage samples. Degradability of dry matter (DM), crude protein (CP) and neutral detergent fibre (NDF......) of 61 samples of perennial ryegrass (Lolium perenne L.) and orchardgrass (Dactylis glomerata L.) was tested by using the in situ technique. The grass samples were harvested at three different stages, early vegetative growth, early reproductive growth and late reproductive growth. Degradability...

  13. Prospects for Hybrid Breeding in Bioenergy Grasses

    DEFF Research Database (Denmark)

    Aguirre, Andrea Arias; Studer, Bruno; Frei, Ursula

    2012-01-01

    , we address crucial topics to implement hybrid breeding, such as the availability and development of heterotic groups, as well as biological mechanisms for hybridization control such as self-incompatibility (SI) and male sterility (MS). Finally, we present potential hybrid breeding schemes based on SI...... of different hybrid breeding schemes to optimally exploit heterosis for biomass yield in perennial ryegrass (Lolium perenne L.) and switchgrass (Panicum virgatum), two perennial model grass species for bioenergy production. Starting with a careful evaluation of current population and synthetic breeding methods...

  14. Multiple resistance to glyphosate, paraquat and ACCase-inhibiting herbicides in Italian ryegrass populations from California: confirmation and mechanisms of resistance.

    Science.gov (United States)

    Tehranchian, Parsa; Nandula, Vijay; Jugulam, Mithila; Putta, Karthik; Jasieniuk, Marie

    2018-04-01

    Glyphosate, paraquat and acetyl CoA carboxylase (ACCase)-inhibiting herbicides are widely used in California annual and perennial cropping systems. Recently, glyphosate, paraquat, and ACCase- and acetolactate synthase (ALS)-inhibitor resistance was confirmed in several Italian ryegrass populations from the Central Valley of California. This research characterized the possible mechanisms of resistance. Multiple-resistant populations (MR1, MR2) are resistant to several herbicides from at least three modes of action. Dose-response experiments revealed that the MR1 population was 45.9-, 122.7- and 20.5-fold, and the MR2 population was 24.8-, 93.9- and 4.0-fold less susceptible to glyphosate, sethoxydim and paraquat, respectively, than the susceptible (Sus) population. Accumulation of shikimate in Sus plants was significantly greater than in MR plants 32 h after light pretreatments. Glyphosate resistance in MR plants was at least partially due to Pro106-to-Ala and Pro106-to-Thr substitutions at site 106 of 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). EPSPS gene copy number and expression level were similar in plants from the Sus and MR populations. An Ile1781-to-Leu substitution in ACCase gene of MR plants conferred a high level of resistance to sethoxydim and cross-resistance to other ACCase-inhibitors. Radiolabeled herbicide studies and phosphorimaging indicated that MR plants had restricted translocation of 14 C-paraquat to untreated leaves compared to Sus plants. This study shows that multiple herbicide resistance in Italian ryegrass populations in California, USA, is due to both target-site and non-target-site resistance mechanisms. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  15. Accuracy of Genomic Prediction in a Commercial Perennial Ryegrass Breeding Program

    Directory of Open Access Journals (Sweden)

    Dario Fè

    2016-11-01

    Full Text Available The implementation of genomic selection (GS in plant breeding, so far, has been mainly evaluated in crops farmed as homogeneous varieties, and the results have been generally positive. Fewer results are available for species, such as forage grasses, that are grown as heterogenous families (developed from multiparent crosses in which the control of the genetic variation is far more complex. Here we test the potential for implementing GS in the breeding of perennial ryegrass ( L. using empirical data from a commercial forage breeding program. Biparental F and multiparental synthetic (SYN families of diploid perennial ryegrass were genotyped using genotyping-by-sequencing, and phenotypes for five different traits were analyzed. Genotypes were expressed as family allele frequencies, and phenotypes were recorded as family means. Different models for genomic prediction were compared by using practically relevant cross-validation strategies. All traits showed a highly significant level of genetic variance, which could be traced using the genotyping assay. While there was significant genotype × environment (G × E interaction for some traits, accuracies were high among F families and between biparental F and multiparental SYN families. We have demonstrated that the implementation of GS in grass breeding is now possible and presents an opportunity to make significant gains for various traits.

  16. An experimental study on mass loading of soil particles on plant surfaces

    International Nuclear Information System (INIS)

    Li, J. G.; Gerzabek, M. H.; Mueck, K.

    1994-01-01

    Radionuclide contaminated soil adhered to plant surfaces can contribute to human ingestion dose. To determine this contribution, a method of 46 Sc neutron activation analysis was established and tested, by which a detection limit of 0.05 mg soil per g dry plant biomass can be obtained. In the field and greenhouse experiment the mass loading of soil on ryegrass (Lolium perenne L.) and broadbean (Vicia faba L.) was investigated and the contribution from rainsplash and wind erosion were evaluated separately. Soil retained on plant surfaces in field conditions in Seibersdorf/Austria was 5.77 ± 1.44 mg soil per g dry plant for ryegrass and 9.51 ± 0.73 mg soil per g dry plant for broadbean. Estimates of contribution from rainsplash and wind erosion to soil contamination of plants during the experimental period are 68 % and 32 % for broadbean 47 % and 53 % for ryegrass respectively. Mass loading results from field studies indicate that soil adhesion on plant surfaces can contribute up to 23 % of plant 137 Cs contamination, the transfer factors modified by mass loading decline differently, depending on 137 Cs concentration of the soil and the soil mass adhered to plant surfaces. (author)

  17. The role of the Oregon State University Endophyte Service Laboratory in diagnosing clinical cases of endophyte toxicoses.

    Science.gov (United States)

    Craig, A Morrie; Blythe, Linda L; Duringer, Jennifer M

    2014-07-30

    The Oregon State University Colleges of Veterinary Medicine and Agricultural Sciences instituted the Endophyte Service Laboratory to aid in diagnosing toxicity problems associated with cool-season grasses in livestock. The endophyte (Neotyphodium coenophalum) present in tall fescue (Festuca arundinacea) produces ergopeptine alkaloids, of which ergovaline is the molecule used to determine exposure and toxicity thresholds for the vasoconstrictive conditions "fescue foot" and "summer slump". Another vasoconstrictive syndrome, "ergotism," is caused by a parasitic fungus, Claviceps purpurea, and its primary toxin, ergotamine. "Ryegrass staggers" is a neurological condition that affects livestock consuming endophyte (Neotyphodium lolii)-infected perennial ryegrass (Lolium perenne) with high levels of lolitrem B. HPLC-fluorescent analytical methods for these mycotoxins are described and were used to determine threshold levels of toxicity for ergovaline and lolitrem B in cattle, sheep, horses, and camels. In addition, six clinical cases in cattle are presented to illustrate diagnosis of these three diseases.

  18. Chromosome duplication in Lolium multiflorum Lam.

    Directory of Open Access Journals (Sweden)

    Roselaine Cristina Pereira

    2014-11-01

    Full Text Available Artificial chromosome duplication of diploid genotypes of Lolium multiflorum (2n=2x=14 is worthy to breeding, and aims to increase the expression of traits with agronomic interest. The purpose of this study was to obtain polyploid plants of L. multiflorum from local diploid populations in order to exploit adaptation and future verification of the effects of polyploidy in agronomic traits. Seedlings were immersed in different colchicine solutions for an exposure time of 3h and 24h. Ploidy determination was made by the DNA content and certified by chromosomes counts. The plants confirmed as tetraploids were placed in a greenhouse, and, at flowering, pollen viability was evaluated, and seeds were harvested to assess the stability of the progenies. The percentage of polyploids obtained was 20%. Pollen viability of the tetraploids generated ranged from 58% to 69%. The tetraploid plants obtained in the experiment generated 164 progenies, of which 109 presented DNA content compatible with the tetraploid level, showing stability of chromosome duplication in the filial generation.

  19. Assessing Nitrogen Use Efficiency and Nitrogen Loss in a Forage-Based System Using a Modeling Approach

    Directory of Open Access Journals (Sweden)

    Chiara Piccini

    2016-04-01

    Full Text Available In intensive agriculture, N supply often exceeds crop requirements, even in nitrate vulnerable zones (NVZ. In farmland, the N surplus gives rise to NO3− leaching and consequent groundwater pollution. The present study aimed at proposing measures to reduce N leaching and hence improve N efficiency in a buffalo livestock farm located in the NVZ of Latina plain (Central Italy. The farm was cultivated with forage crops in a double annual crop rotation: Italian ryegrass (Lolium multiflorum Lam. in winter and silage corn (Zea mays L. in summer. Mineral and organic fertilizers were supplied to both crops. The annual N budget and soil solution NO3-N concentrations were evaluated using a modeling approach. The performance of the WinEPIC model in simulating the response of the NO3-N concentration in percolation to the N application rate was assessed and validated by field measurements of the NO3-N concentration in the soil solution. Three scenarios were proposed to identify the best practice to minimize the environmental impact of N application without significant yield loss. Also, recommendations of best practices in N fertilization and animal manure spreading were given. This study thus provides useful preliminary information for decision-making in agriculture/environmental policies.

  20. Plants growing on contaminated and brownfield sites appropriate for use in Organisation for Economic Co-operation and Development terrestrial plant growth test.

    Science.gov (United States)

    Sinnett, Danielle E; Lawrence, Victoria K; Hutchings, Tony R; Hodson, Mark E

    2011-01-01

    The Organisation for Economic Co-operation and Development (OECD) terrestrial plant test is often used for the ecological risk assessment of contaminated land. However, its origins in plant protection product testing mean that the species recommended in the OECD guidelines are unlikely to occur on contaminated land. Six alternative species were tested on contaminated soils from a former Zn smelter and a metal fragmentizer with elevated concentrations of Cd, Cu, Pb, and Zn. The response of the alternative species was compared with that of two species recommended by the OECD: Lolium perenne (perennial ryegrass) and Trifolium pratense (red clover). Urtica dioica (stinging nettle) and Poa annua (annual meadowgrass) had low emergence rates in the control soil and so may be considered unsuitable. Festuca rubra (Chewings fescue), Holcus lanatus (Yorkshire fog), Senecio vulgaris (common groundsel), and Verbascum thapsus (great mullein) offer good alternatives to the OECD species. In particular, H. lanatus and S. vulgaris were more sensitive to the soils with moderate concentrations of Cd, Cu, Pb, and Zn than the OECD species. © 2010 SETAC.

  1. Anaerobic Digestion of Saline Creeping Wild Ryegrass for Biogas Production and Pretreatment of Particleboard Material

    Science.gov (United States)

    The objective of this research was to develop an integrated process to produce biogas and high-quality particleboard using saline creeping wild ryegrass (CWR), Leymus triticoides through anaerobic digestion (AD). Besides producing biogas, AD also serves as a pretreatment method to remove the wax la...

  2. Candidate Herbaceous Plants for Phytoremediation of Energetics on Ranges. Strategic Environmental Research and Development Program

    Science.gov (United States)

    2007-09-01

    fescue P medium medium N-W NE, NH G.c. CCREL 10 Hordeum sativum Barley TNT A medium medium N&S AK, HW 4 Lolium multiflorum Ryegrass TNT AP... Allium schoenopra- sum Wild chives TNT P small small N AK 4 Brassica rapa Canola RDX,HMX AB medium medium N&S AK, HW, IL, PR, VI 4, 20 Bupleurum...TNT, HMX A medium medium N&S IL, PR, VI JAAP 4, 12.,13 Pisum sativum Pea TNT A small large N&S 4 Raphanus sativus Radish RDX A tap small N

  3. Lucerne varieties for continuous grazing

    DEFF Research Database (Denmark)

    Søegaard, Karen

    2012-01-01

    severe grazing with heifers in two cutting/grazing managements. Two new varieties, Verbena and Camporegio, and an older variety Luzelle were established in 2009 in pure stands and in two different mixtures with perennial ryegrass (Lolium perenne). Camporegio had the lowest yield, the lowest competitive...... strength, the lowest plant density in spring, and the density was most reduced during grazing. The results could not confirm significant differences between the new and the older varieties. The results for Luzelle were generally between Verbena and Camporegio. The varieties did not differ in herbage...

  4. Estimating legume N-2 fixation in grass-clover mixtures of a grazed organic cropping system using two N-15 methods

    DEFF Research Database (Denmark)

    Vinther, F.P.; Jensen, E.S.

    2000-01-01

    The input of Nitrogen (N) through symbiotic N-2 fixation (SNF) in grass-clover mixtures was determined in an organic cropping. system for grazing during 3 years. The mixture of perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.) was established by undersowing in spring...... barley (Hordeum vulgare L.) and maintained subsequently for two production years. Dinitrogen fixation was determined using the N-15 isotope dilution techniques and two labelling procedures. Using either pre-labelling of the soil with immobilisation of the N-15 by addition of a carbon source before...

  5. Stability of Genome Composition and Recombination between Homoeologous Chromosomes in Festulolium (Festuca × Lolium) Cultivars

    Czech Academy of Sciences Publication Activity Database

    Kopecký, David; Šimoníková, Denisa; Ghesquière, M.; Doležel, Jaroslav

    2017-01-01

    Roč. 151, č. 2 (2017), s. 106-114 ISSN 1424-8581 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : Festulolium * Genome composition * Genomic in situ hybridization * Grass hybrids * Homoeologous recombination * Lolium × Festuca Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Plant sciences, botany Impact factor: 1.354, year: 2016

  6. Leaf economics spectrum-productivity relationships in intensively grazed pastures depend on dominant species identity.

    Science.gov (United States)

    Mason, Norman W H; Orwin, Kate; Lambie, Suzanne; Woodward, Sharon L; McCready, Tiffany; Mudge, Paul

    2016-05-01

    Plant functional traits are thought to drive variation in primary productivity. However, there is a lack of work examining how dominant species identity affects trait-productivity relationships. The productivity of 12 pasture mixtures was determined in a 3-year field experiment. The mixtures were based on either the winter-active ryegrass (Lolium perenne) or winter-dormant tall fescue (Festuca arundinacea). Different mixtures were obtained by adding forb, legume, and grass species that differ in key leaf economics spectrum (LES) traits to the basic two-species dominant grass-white clover (Trifolium repens) mixtures. We tested for correlations between community-weighted mean (CWM) trait values, functional diversity, and productivity across all plots and within those based on either ryegrass or tall fescue. The winter-dormant forb species (chicory and plantain) had leaf traits consistent with high relative growth rates both per unit leaf area (high leaf thickness) and per unit leaf dry weight (low leaf dry matter content). Together, the two forb species achieved reasonable abundance when grown with either base grass (means of 36% and 53% of total biomass, respectively, with ryegrass tall fescue), but they competed much more strongly with tall fescue than with ryegrass. Consequently, they had a net negative impact on productivity when grown with tall fescue, and a net positive effect when grown with ryegrass. Strongly significant relationships between productivity and CWM values for LES traits were observed across ryegrass-based mixtures, but not across tall fescue-based mixtures. Functional diversity did not have a significant positive effect on productivity for any of the traits. The results show dominant species identity can strongly modify trait-productivity relationships in intensively grazed pastures. This was due to differences in the intensity of competition between dominant species and additional species, suggesting that resource-use complementarity is a

  7. Nucleotide diversity and linkage disequilibrium in five Lolium perenne genes with putative role in shoot branching

    DEFF Research Database (Denmark)

    Brazauskas, Gintaras; Pašakinskienė, Izolda; Asp, Torben

    2010-01-01

    Knowledge on nucleotide diversity and linkage disequilibrium (LD) patterns is prerequisite for association analyses. However, little is known about the nucleotide diversity in the evolutionary important ryegrass shoot morphology genes. Five candidate genes, LpIAA1, LpRUB1, LpBRI1, LpSHOOT1 and Lp...

  8. Evaluation of Turf-type Interspecific Hybrids of Meadow Fescue with Perennial Ryegrass for Improved Stress Tolerance

    Czech Academy of Sciences Publication Activity Database

    Barnes, B.D.; Kopecký, David; Lukaszewski, A.J.; Baird, J. H.

    2014-01-01

    Roč. 54, č. 1 (2014), s. 355-365 ISSN 0011-183X R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : LOLIUM-FESTUCA COMPLEX * TALL FESCUE * INTERGENERIC HYBRIDS Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.575, year: 2014

  9. Seasonal and annual variations of metal uptake, bioaccumulation, and toxicity in Trifolium repens and Lolium perenne growing in a heavy metal-contaminated field.

    Science.gov (United States)

    Bidar, Géraldine; Pruvot, Christelle; Garçon, Guillaume; Verdin, Anthony; Shirali, Pirouz; Douay, Francis

    2009-01-01

    The reclamation of nonferrous metal-polluted soil by phytoremediation requires an overall and permanent plant cover. To select the most suitable plant species, it is necessary to study metal effects on plants over the time, thereby checking that metals remain stored in root systems and not transferred to aerial parts. In this purpose, the seasonal and annual variations of metal bioaccumulation, transfer, and phytotoxicity in Trifolium repens and Lolium perenne grown in a Cd-, Pb-, and Zn-contaminated soil were also studied. The experimental site was located near a closed smelter. In spring 2004, two areas were sown with T. repens and L. perenne, respectively. Thereafter, the samplings of plant roots and shoots and surrounding soils were realized in autumn 2004 and spring and autumn 2005. The soil agronomic characteristics, the Cd, Pb, and Zn concentrations in the surrounded soils and plant organs, as well as the oxidative alterations (superoxide dismutase [SOD], malondialdehyde [MDA], and 8-hydroxy-2'-deoxyguanosine [8-OHdG]) in plant organs were carried out. Whatever the sampling period, metal concentrations in soils and plants were higher than background values. Contrary to the soils, the fluctuations of metal concentrations were observed in plant organs over the time. Bioaccumulation and transfer factors confirmed that metals were preferentially accumulated in the roots as follows: Cd>Zn>Pb, and their transfer to shoots was limited. Foliar metal deposition was also observed. The results showed that there were seasonal and annual variations of metal accumulation in the two studied plant species. These variations differed according to the organs and followed nearly the same pattern for the two species. Oxidative alterations were observed in plant organs with regard to SOD antioxidant activities, MDA, and 8-OHdG concentrations. These alterations vary according to the temporal variations of metal concentrations. Metal concentrations in surrounded soils and plant

  10. Effects of feeding green forage of sulla (Hedysarum coronarium L.) on lamb growth and carcass and meat quality.

    Science.gov (United States)

    Bonanno, A; Di Miceli, G; Di Grigoli, A; Frenda, A S; Tornambè, G; Giambalvo, D; Amato, G

    2011-01-01

    The nutritional effects of sulla (Hedysarum coronarium L.) forage containing condensed tannins (CT) on growth of lambs, and carcass and meat quality were investigated. Thirty-two male Comisana lambs aged 100 ± 8 days weighing 19.0 ± 2.8 kg were fed fresh forage of sulla or CT-free annual ryegrass (Lolium multiflorum Lam. subsp. Wersterwoldicum) for 49 days until slaughter; in addition, each lamb was supplied with 200 g/days of concentrate. Eight lambs per diet had been previously treated with anthelmintic drugs to remove nematode parasites. Measurements of BW and feed intake, and counts of faecal nematode eggs were made. Carcass parameters were recorded after slaughter, and tissue components of the hind leg were determined. Longissimus dorsi meat was evaluated for pH, colour, thawing and cooking losses, Warner-Bratzler shear force, chemical composition and sensory properties based on triangle tests. Relative to ryegrass-fed lambs, sulla-fed lambs had significantly greater dry matter (DM) and protein intake, a more favourable feed conversion ratio, and superior growth rate, final BW at 150 days of age, carcass weight, yield and fatness. These results were attributed to the high protein and non-structural carbohydrate content of sulla, and also to the moderate CT content of sulla (16.7 and 20.3 g/kg of DM in offered and consumed sulla forage, respectively). Anthelmintic treatment did not affect lamb growth, as the level of parasitic infection (initial and final) was low. The physical, chemical and sensory properties of the lamb meat were not influenced by diet.

  11. Behavior of decabromodiphenyl ether (BDE-209) in soil: Effects of rhizosphere and mycorrhizal colonization of ryegrass roots

    Energy Technology Data Exchange (ETDEWEB)

    Wang Sen [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085 (China); Zhang Shuzhen, E-mail: szzhang@rcees.ac.cn [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085 (China); Huang, Honglin [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085 (China); Christie, Peter [Agri-Environment Branch, Agri-Food and Biosciences Institute, Newforge Lane, Belfast BT9 5PX (United Kingdom)

    2011-03-15

    A rhizobox experiment was conducted to investigate degradation of decabromodiphenyl ether (BDE-209) in the rhizosphere of ryegrass and the influence of root colonization with an arbuscular mycorrhizal (AM) fungus. BDE-209 dissipation in soil varied with its proximity to the roots and was enhanced by AM inoculation. A negative correlation (P < 0.001, R{sup 2} = 0.66) was found between the residual BDE-209 concentration in soil and soil microbial biomass estimated as the total phospholipid fatty acids, suggesting a contribution of microbial degradation to BDE-209 dissipation. Twelve and twenty-four lower brominated PBDEs were detected in soil and plant samples, respectively, with a higher proportion of di- through hepta-BDE congeners in the plant tissues than in the soils, indicating the occurrence of BDE-209 debromination in the soil-plant system. AM inoculation increased the levels of lower brominated PBDEs in ryegrass. These results provide important information about the behavior of BDE-209 in the soil-plant system. - Research highlights: > BDE-209 dissipation in soil was affected by the proximity to the roots. > Microbial degradation contributes greatly to BDE-209 dissipation in the soil. > Twelve and twenty-four lower brominated PBDEs were detected in soil and plant samples. > AM inoculation increased root uptake and accumulation of BDE-209. - BDE-209 dissipation and degradation in soil were affected by both its proximity to ryegrass roots and inoculation with an AM fungus.

  12. Environmental life cycle assessments of producing maize, grass-clover, ryegrass and winter wheat straw for biorefinery

    DEFF Research Database (Denmark)

    Parajuli, Ranjan; Kristensen, Ib Sillebak; Knudsen, Marie Trydeman

    2017-01-01

    The aim of this study is to assess the potential environmental impacts of producing maize, grass-clover, ryegrass, and straw from winter wheat as biomass feedstocks for biorefinery. The Life Cycle Assessment (LCA) method included the following impact categories: Global Warming Potential (GWP100),...

  13. Effect of seed rate and row spacing in seed production of Festulolium

    DEFF Research Database (Denmark)

    Deleuran, L C; Gislum, R; Boelt, B

    2010-01-01

    -type festulolium, Paulita, and in a fescue-type festulolium, Hykor. The objectives were to examine the influence of row spacing (12, 24, and 36 cm) and seed rate (8, 12, or 16 kg ha-1) on plant establishment, development, and seed yield. Observations of autumn and spring in-row plant densities indicated......Festulolium ( Festulolium) is a cross between the two species fescue (Festuca L.) and ryegrass (Lolium L.) and is a promising forage and seed crop. To stimulate the production of Danish organic festulolium seeds a three-year field experiment was performed from 1999 to 2002 in a ryegrass...... satisfactory plant establishment in all combinations of seed rate and row spacing. The number of reproductive tillers was in the range from 800 to 2200 m-2 in Paulita and from 500 to 1300 m-2 in Hykor. Row spacing had an effect on the number of reproductive tillers and in both cultivars the highest number...

  14. Mineralization-immobilization and plant uptake of nitrogen as influenced by the spatial distribution of cattle slurry in soils of different texture

    DEFF Research Database (Denmark)

    Sørensen, P.; Jensen, E.S.

    1995-01-01

    The effect of incorporating cattle slurry in soil, either by mixing or by simulated injection into a hollow in soil, on the ryegrass uptake of total N and (NH4+)-N-15-N was determined in three soils of different textrue. The N accumulation in Italian ryegrass (Lolium multiflorum L.) from slurry N...... and from an equivalent amount of NH4+-N in ((NH4)-N-15) SO4 (control) was measured during 6 months of growth in pots. After this period the total recovery of labelled N in the top soil plus herbage was similar in the slurry and the control treatments. This indicated that gaseous losses from slurry NH4+-N...... were insignificant. Consequently, the availability of slurry N to plants was mainly influenced by the mineralization-immobilization processes. The apparent utilization of slurry NH4+-N mixed into soil was 7%, 14% and 24% lower than the utilization of (NH4)(2)SO4-N in a sand soil, a sandy loam soil...

  15. The fate of fresh and stored 15N-labelled sheep urine and urea applied to a sandy and a sandy loam soil using different application strategies

    DEFF Research Database (Denmark)

    Sørensen, P.; Jensen, E.S.

    1996-01-01

    The fate of nitrogen from N-15-labelled sheep urine and urea applied to two soils was studied under field conditions. Labelled and stored urine equivalent to 204 kg N ha(-1) was either incorporated in soil or applied to the soil surface prior to sowing of Italian ryegrass (Lolium multiflorum L...... and soil was not significantly different for incorporated urine and urea. Almost all the supplied labelled N was accounted for in soil and herbage in the sandy loam soil, whereas 33-34% of the labelled N was unaccounted for in the sandy soil. When the stored urine was applied to the soil surface, 20...... was applied to growing ryegrass at the sandy loam soil, the immobilization of urine-derived N was significantly reduced compared to application prior to sowing. The results indicated that the net mineralization of urine N was similar to that of urea in the sandy soil, but only about 75% of the urine N was net...

  16. Diversity of alkane degrading bacteria associated with plants in a petroleum oil-contaminated environment and expression of alkane monooxygenase (alkB) genes

    Science.gov (United States)

    Andria, V.; Yousaf, S.; Reichenauer, T. G.; Smalla, K.; Sessitsch, A.

    2009-04-01

    Among twenty-six different plant species, Italian ryegrass (Lolium multiflorum var. Taurus), Birdsfoot trefoil (Lotus corniculatus var. Leo), and the combination of both plants performed well in a petroleum oil contaminated soil. Hydrocarbon degrading bacteria were isolated from the rhizosphere, root interior and shoot interior and subjected to the analysis of 16S rRNA, the 16S and 23S rRNA intergenic spacer region and alkane hydroxylase genes. Higher numbers of culturable, degrading bacteria were associated with Italian ryegrass, which were also characterized by a higher diversity, particularly in the plant interior. Only half of the isolated bacteria hosted known alkane hydroxylase genes (alkB and cytochrome P153-like). Our results indicated that alkB genes have spread through horizontal gene transfer, particularly in the Italian ryegrass rhizosphere, and suggested mobility of catabolic genes between Gram-negative and Gram-positive bacteria. We furthermore studied the colonization behaviour of selected hydrocarbon-degrading strains (comprising an endopyhte and a rhizosphere strain) as well as the expression of their alkane monooxygenase genes in association with Italian ryegrass. Results showed that the endophyte strain better colonized the plant, particularly the plant interior, and also showed higher expression of alkB genes suggesting a more efficient degradation of the pollutant. Furthermore, plants inoculated with the endophyte were better able to grow in the presence of diesel. The rhizosphere strain colonized primarily the rhizosphere and showed low alkB gene expression in the plant interior.

  17. Targeted genotyping-by-sequencing permits cost-effective identification and discrimination of pasture grass species and cultivars.

    Science.gov (United States)

    Pembleton, Luke W; Drayton, Michelle C; Bain, Melissa; Baillie, Rebecca C; Inch, Courtney; Spangenberg, German C; Wang, Junping; Forster, John W; Cogan, Noel O I

    2016-05-01

    A targeted amplicon-based genotyping-by-sequencing approach has permitted cost-effective and accurate discrimination between ryegrass species (perennial, Italian and inter-species hybrid), and identification of cultivars based on bulked samples. Perennial ryegrass and Italian ryegrass are the most important temperate forage species for global agriculture, and are represented in the commercial pasture seed market by numerous cultivars each composed of multiple highly heterozygous individuals. Previous studies have identified difficulties in the use of morphophysiological criteria to discriminate between these two closely related taxa. Recently, a highly multiplexed single nucleotide polymorphism (SNP)-based genotyping assay has been developed that permits accurate differentiation between both species and cultivars of ryegrasses at the genetic level. This assay has since been further developed into an amplicon-based genotyping-by-sequencing (GBS) approach implemented on a second-generation sequencing platform, allowing accelerated throughput and ca. sixfold reduction in cost. Using the GBS approach, 63 cultivars of perennial, Italian and interspecific hybrid ryegrasses, as well as intergeneric Festulolium hybrids, were genotyped. The genetic relationships between cultivars were interpreted in terms of known breeding histories and indistinct species boundaries within the Lolium genus, as well as suitability of current cultivar registration methodologies. An example of applicability to quality assurance and control (QA/QC) of seed purity is also described. Rapid, low-cost genotypic assays provide new opportunities for breeders to more fully explore genetic diversity within breeding programs, allowing the combination of novel unique genetic backgrounds. Such tools also offer the potential to more accurately define cultivar identities, allowing protection of varieties in the commercial market and supporting processes of cultivar accreditation and quality assurance.

  18. Carbon balance and water use efficiency of frequently cut Lolium perenne L. swards at elevated carbon dioxide

    NARCIS (Netherlands)

    Schapendonk, A.H.C.M.; Dijkstra, P.; Groenwold, J.; Pot, C.S.; Geijn, van de S.C.

    1997-01-01

    The impact of doubled atmospheric [CO2] on the carbon balance of regularly cut Lolium perenne L. swards was studied for two years under semi-field conditions in the Wageningen Rhizolab. CO2 and H2O vapour exchange rates of the swards were measured continuously for two years in transparent

  19. Enzymatic production of wheat and ryegrass derived xylooligosaccharides and evaluation of their in vitro effect on pig gut microbiota

    DEFF Research Database (Denmark)

    Dotsenko, Gleb; Meyer, Anne S.; Canibe, Nuria

    2017-01-01

    This study examines enzymatic production of linear xylooligosaccharides (XOS) and branched arabinoxylooligosaccharides (AXOS) from monocotyledonous biomass, wheat straw and ryegrass, and compares the in vitro effects of these XOS and AXOS on pig gut microbiota. XOS and AXOS were obtained from...... the biomass by treatment with different endo-1,4-β-xylanases. XOS of DP2-6 from wheat straw, obtained after treatment with Aspergillus niger endo GH11, suppressed growth of Clostridium perfringens and resulted in a high level of lactic acid production when fermented in vitro by pig fecal microbiota...... (GH11). These results indicate that wheat straw as well as green grass biomass such as ryegrass have potential as new sources of putative prebiotics for pig feed....

  20. Flowering does not decrease vegetative competitiveness of Lolium perenne

    DEFF Research Database (Denmark)

    Thiele, Jan; Bagger Jørgensen, Rikke; Hauser, Thure Pavlo

    2009-01-01

    as reduced flowering could free resources and increase productivity. But if so, less-flowering cultivars might be more competitive and invade natural swards. We tested for costs of sexual reproduction on vegetative propagation and competitiveness of the perennial grass Lolium perenne, one of the most...... treatments were successful in producing clones with largely differing degrees of flowering. However, we found no negative correlation between flowering and vegetative propagation and competitiveness. Early and strongly flowering southern provenances showed less clonal growth and higher mortality, but within...... provenances the response of clone diameter to flowering was positive or neutral. We conclude that investment of resources into flowering has no measurable costs on vegetative propagation and competitiveness of L. perenne. The apparent lack of costs of sexual reproduction could be explained by bet...

  1. Applying carbon dioxide, plant growth-promoting rhizobacterium and EDTA can enhance the phytoremediation efficiency of ryegrass in a soil polluted with zinc, arsenic, cadmium and lead.

    Science.gov (United States)

    Guo, Junkang; Feng, Renwei; Ding, Yongzhen; Wang, Ruigang

    2014-08-01

    This study was conducted to investigate the use of elevated carbon dioxide (CO2), plant growth-promoting rhizobacterium Burkholderia sp. D54 (PGPR) and ethylenediaminetetraacetic acid (EDTA) to enhance the phytoextraction efficiency of ryegrass in response to multiple heavy metal (or metalloid)-polluted soil containing zinc (Zn), arsenic (As), cadmium (Cd) and lead (Pb). All of the single or combined CO2, PGPR and EDTA treatments promoted ryegrass growth. The stimulation of ryegrass growth by CO2 and PGPR could primarily be attributed to the regulation of photosynthesis rather than decreased levels of Zn, As and Cd in the shoots. Most treatments seemed to reduce the Zn, As and Cd contents in the shoots, which might be associated with enhanced shoot biomass, thus causing a "dilution effect" regarding their levels. The combined treatments seemed to perform better than single treatments in removing Zn, As, Cd and Pb from soil, judging from the larger biomass and relatively higher total amounts (TAs) of Zn, As, Cd and Pb in both the shoots and roots. Therefore, we suggest that the CO2 plus PGPR treatment will be suitable for removing Zn, As, Cd and Pb from heavy metal (or metalloid)-polluted soils using ryegrass as a phytoremediation material. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Ensiling on chemical composition and in vitro fermentation in rabbits of different forages

    Directory of Open Access Journals (Sweden)

    Juan Carlos Angeles Hernandez

    Full Text Available ABSTRACT: The effect of chemical composition of silages on in vitro gas fermentation profiles in rabbits was examined. The study was performed using 7 silages: beans (Phaseolus vulgaris, faba bean (FB, Vicia faba, common vetch (CV, Vicia sativa, ryegrass (Lolium perenne, barley (B, Hordeum vulgare, barley with common vetch (BCV and barley with faba bean (BFB. We used 3 New Zealand White (NZW rabbits as donors of caecal content in each incubation run (n=3. Data were analyzed in a completely randomized experimental design. The CV silage showed higher values of crude protein (CP, followed by FB and bean silages (P<0.001. Barley silage had the lowest CP content (96g kg-1 DM (P=0.001. The NDF and ADF content were lower (P<0.001 for beans and CV compared with the rest of the forage silages. Ryegrass silage had higher values of dry matter degradation, organic matter degradation, relative GP and SCFA (P<0.001. The highest values of digestible energy were for CV and bean silages (P<0.001. Ryegrass and CV silages showed higher levels in GP parameters, which could be associated with their better chemical composition characteristics, mainly protein and fiber content.

  3. The linear accumulation of atmospheric mercury by vegetable and grass leaves: Potential biomonitors for atmospheric mercury pollution.

    Science.gov (United States)

    Niu, Zhenchuan; Zhang, Xiaoshan; Wang, Sen; Ci, Zhijia; Kong, Xiangrui; Wang, Zhangwei

    2013-09-01

    One question in the use of plants as biomonitors for atmospheric mercury (Hg) is to confirm the linear relationships of Hg concentrations between air and leaves. To explore the origin of Hg in the vegetable and grass leaves, open top chambers (OTCs) experiment was conducted to study the relationships of Hg concentrations between air and leaves of lettuce (Lactuca sativa L.), radish (Raphanus sativus L.), alfalfa (Medicago sativa L.) and ryegrass (Lolium perenne L.). The influence of Hg in soil on Hg accumulation in leaves was studied simultaneously by soil Hg-enriched experiment. Hg concentrations in grass and vegetable leaves and roots were measured in both experiments. Results from OTCs experiment showed that Hg concentrations in leaves of the four species were significantly positively correlated with those in air during the growth time (p  0.05). Thus, Hg in grass leaves is mainly originated from the atmosphere, and grass leaves are more suitable as potential biomonitors for atmospheric Hg pollution. The effect detection limits (EDLs) for the leaves of alfalfa and ryegrass were 15.1 and 22.2 ng g(-1), respectively, and the biological detection limit (BDL) for alfalfa and ryegrass was 3.4 ng m(-3).

  4. An experimental study on mass loading of soil particles on plant surfaces

    International Nuclear Information System (INIS)

    Li, J.; Gerzabek, M.H.; Mueck, K.

    1994-03-01

    Radionuclide contaminated soil adhered to plant surfaces can contribute to human ingestion dose. To determine this contribution, a method of 46 Sc neutron activation analysis was established and tested, by which a detection limit of 0.05 mg soil per g dry plant biomass can be obtained. In the field and greenhouse experiment the mass loading of soil on ryegrass (Lolium perenne L.) and broad bean (Vicia faba L.) was investigated and the contribution from rainsplash and wind erosion were evaluated separately. Soil retained on plant surfaces in field conditions in Seibersdorf/Austria was 5.77 ± 1.44 mg soil per g dry plant for ryegrass and 9.51 ± 0.73 mg soil per g dry plant for broad bean. Estimates of contribution from rainsplash and wind erosion to soil contamination of plant during the experimental period are 68 % and 32 % for broadbean, 47 % and 53 % for ryegrass, respectively. Mass loading results from field studies indicate that soil adhesion on plant surfaces can contribute up to 23 % of plant 137 Cs contamination, the transfer factors modified by mass loading decline differently, depending on 137 Cs concentration of the soil and the soil mass adhered to plant surfaces. (authors)

  5. Orthology Guided Transcriptome Assembly of Italian Ryegrass and Meadow Fescue for Single-Nucleotide Polymorphism Discovery

    Czech Academy of Sciences Publication Activity Database

    Stočes, Štěpán; Ruttink, T.; Bartoš, Jan; Studer, B.; Yates, S.; Zwierzykowski, Z.; Abrouk, Michael; Roldán-Ruiz, I.; Książczyk, T.; Rey, Elodie; Doležel, Jaroslav; Kopecký, David

    2016-01-01

    Roč. 9, č. 3 (2016) ISSN 1940-3372 R&D Projects: GA ČR GAP501/11/05043; GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : festuca-pratensis huds. * dna-sequencing data * lolium-perenne l. * rna-seq data * genome * cultivars * festulolium * multiflorum * hybrid * recombination Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.736, year: 2016

  6. Strategic timing of nitrogen fertilization to increase root biomass and nitrogen-use efficiency of Lolium perenne L.

    NARCIS (Netherlands)

    Boer, de H.C.; Deru, J.G.C.; Hoekstra, N.J.; Eekeren, van N.

    2016-01-01

    Aims: During the first days after harvest of Lolium perenne L., N remobilized from roots and stubble forms the main N source for regrowth. Low N uptake from the soil during this period may lead to N loss if N fertilizer is applied too soon. Furthermore, temporary N deprivation has been found to

  7. STUDIES REGARDING THE CHELATE-INDUCED HYPERACCUMULATION OF CU AND FE USING LOLIUM PERENNE SPECIES IN MINING AREAS

    Directory of Open Access Journals (Sweden)

    ANCA-DIANA PRICOP

    2009-05-01

    Full Text Available The plant capacity to absorb high amounts of metal for a short period of time is the major factor that influences the efficiency of phytoextraction. The hyperaccumulating plants uptake high amounts in their tissues correlated to the metal concentrations in soil. Chelating agents have the capacity to induce the metal accumulation in biomass. They increase metal bioavailability for plants by releasing the metal in accessible forms. The present study emphasizes that in the case of EDTA use, the obtained biomass is smaller compared to the other variants, showing a lower tolerance to this chelating agent of Lolium perenne species. Cu and Fe phytoextraction by Lolium perenne species is higher in the case of EDTA use. Cu bioaccumulation has higher values in variants with compost-sterile mixture ratio of 1:4 in comparison with Fe. In the case of the best compost-sterile mixture ratio of 1:3 the highest biomass is obtained in all the variants, biosolids’ effect being stronger compared to the chelating agent.

  8. Plastome Sequence Determination and Comparative Analysis for Members of the Lolium-Festuca Grass Species Complex

    Science.gov (United States)

    Hand, Melanie L.; Spangenberg, German C.; Forster, John W.; Cogan, Noel O. I.

    2013-01-01

    Chloroplast genome sequences are of broad significance in plant biology, due to frequent use in molecular phylogenetics, comparative genomics, population genetics, and genetic modification studies. The present study used a second-generation sequencing approach to determine and assemble the plastid genomes (plastomes) of four representatives from the agriculturally important Lolium-Festuca species complex of pasture grasses (Lolium multiflorum, Festuca pratensis, Festuca altissima, and Festuca ovina). Total cellular DNA was extracted from either roots or leaves, was sequenced, and the output was filtered for plastome-related reads. A comparison between sources revealed fewer plastome-related reads from root-derived template but an increase in incidental bacterium-derived sequences. Plastome assembly and annotation indicated high levels of sequence identity and a conserved organization and gene content between species. However, frequent deletions within the F. ovina plastome appeared to contribute to a smaller plastid genome size. Comparative analysis with complete plastome sequences from other members of the Poaceae confirmed conservation of most grass-specific features. Detailed analysis of the rbcL–psaI intergenic region, however, revealed a “hot-spot” of variation characterized by independent deletion events. The evolutionary implications of this observation are discussed. The complete plastome sequences are anticipated to provide the basis for potential organelle-specific genetic modification of pasture grasses. PMID:23550121

  9. Transpiration flow controls Zn transport in Brassica napus and Lolium multiflorum under toxic levels as evidenced from isotopic fractionation

    Science.gov (United States)

    Couder, Eléonore; Mattielli, Nadine; Drouet, Thomas; Smolders, Erik; Delvaux, Bruno; Iserentant, Anne; Meeus, Coralie; Maerschalk, Claude; Opfergelt, Sophie; Houben, David

    2015-11-01

    Stable zinc (Zn) isotope fractionation between soil and plant has been used to suggest the mechanisms affecting Zn uptake under toxic conditions. Here, changes in Zn isotope composition in soil, soil solution, root and shoot were studied for ryegrass (Lolium multiflorum L.) and rape (Brassica napus L.) grown on three distinct metal-contaminated soils collected near Zn smelters (total Zn 0.7-7.5%, pH 4.8-7.3). The Zn concentrations in plants reflected a toxic Zn supply. The Zn isotopic fingerprint of total soil Zn varied from -0.05‰ to +0.26 ± 0.02‰ (δ66Zn values relative to the JMC 3-0749L standard) among soils, but the soil solution Zn was depleted in 66Zn, with a constant Zn isotope fractionation of about -0.1‰ δ66Zn unit compared to the bulk soil. Roots were enriched with 66Zn relative to soil solution (δ66Znroot - δ66Znsoil solution = Δ66Znroot-soil solution = +0.05 to +0.2 ‰) and shoots were strongly depleted in 66Zn relative to roots (Δ66Znshoot-root = -0.40 to -0.04 ‰). The overall δ66Zn values in shoots reflected that of the bulk soil, but were lowered by 0.1-0.3 ‰ units as compared to the latter. The isotope fractionation between root and shoot exhibited a markedly strong negative correlation (R2 = 0.83) with transpiration per unit of plant weight. Thus, the enrichment with light Zn isotopes in shoot progressed with increasing water flux per unit plant biomass dry weight, showing a passive mode of Zn transport by transpiration. Besides, the light isotope enrichment in shoots compared to roots was larger for rape than for rye grass, which may be related to the higher Zn retention in rape roots. This in turn may be related to the higher cation exchange capacity of rape roots. Our finding can be of use to trace the biogeochemical cycles of Zn and evidence the tolerance strategies developed by plants in Zn-excess conditions.

  10. Sementes nocivas que ocorreram em amostras de sementes de azevém (Lolium multiflorum, analisadas no Rio Grande do Sul nos anos de 1978 e 1979 Weed seeds in ryegrass seeds, analysed in Rio Grande do Sul, during 1978 and 1979

    Directory of Open Access Journals (Sweden)

    H. Giaretta

    1984-06-01

    Full Text Available Foram levantadas informações sobre a qualidade da semente de azevém utilizadas no Rio Grande do Sul e produzida no próprio Estado ou em outras uni dades da Federação e mesmo em outros Países, nos anos de 1978 e 1979. Estas informações foram obtidas através de fichas e Boletins de Análise de Sementes dos Laboratórios de Análise de Sementes (LAS do Rio Grande do Sul. Em 1978 analisou-se 2.319 t de azevém sendo 74% da semente oriunda do Rio Grande do Sul e 26% introduzida, enquanto que das 4.772 t analisadas em 1979 99,6% são do Rio Grande do Sul e 0,4% são introduzidas. O percentual de sementes de azevém, produzidas no Estado, contaminadas com sementes nocivas foi de 61,5% em 1978 e de 60,0% em 1979; e o de sementes int roduzidas no Estado foi de 45,6% em 1978 e de 29,4%em 1979. Foi observado que ent re as sementes originárias do RS destacaram -se com maior ocorrênci a em 1978 as espécies nocivas de Silene gallica, Setaria geniculata, Anthemis cotula, Digitaria adscendens e Echinochloa spp, enquanto que nas sementes int roduzidas desta caram-se Sida spp e Rumex spp; em 1979, na semente oriunda do Estado desta caram-se Amaranthus spp, Silene gallica e Setaria geniculata, enquanto que nas sementes introduzidas a maior ocorrência foi de Setaria geniculata, Echinochloa spp e Solanum spp.This paper presents a quality record of rye-grass seeds produced in Rio Grande do Sul or imported from other countries. It refers to the presence of weeds in ryegrass during 1978 and 1979. These record were obtained in the Analysis Bulletins at the Seed Analysis Laboratory of the Instituto de Pesquisas Agronômicas (IPAGRO Rio Grande do Sul°Brasil and in those from other institutions. This State produced 74% of 2.319 t analysed seeds and 26% come from other places in 1978. In 1979 4.772 t were registred, 99,6% from here and 0,4% from outside. The percentage of ryegrass seeds contaminated with weed seeds produced in the State, in 1978, were 61

  11. Bicarbonate as tracer for plant assimilated C and homogeneity of 14C and 15N distribution in ryegrass and white clover tissue by alternative labeling approaches

    DEFF Research Database (Denmark)

    Rasmussen, Jim; Kusliene, Gedrime; Jacobsen, Ole Stig

    2013-01-01

    that 15N also had a heterogeneous distribution (up to two orders of magnitude). Conclusion Bicarbonate can efficiently be used to introduce 14C or 13C into plant via the leaf-labeling method. Both 14C and 15N showed heterogeneous distribution in the plant, although the distribution of 15N was more even......Aims: Application of carbon (C) and nitrogen (N) isotopes is an essential tool to study C and N flows in plant-soil-microorganisms systems. When targeting single plants in a community the tracers need to be added via e.g., leaf-labeling or stem-feeding approaches. In this study we: (i) investigated...... if bicarbonate can be used to introduce 14C (or 13C) into white clover and ryegrass, and (ii) compared the patterns of 14C and 15N allocation in white clover and ryegrass to evaluate the homogeneity of tracer distribution after two alternative labeling approaches. Methods Perennial ryegrass and white clover were...

  12. Tritium forms discrimination in ryegrass under constant tritium exposure: From seed germination to seedling autotrophy.

    Science.gov (United States)

    Renard, H; Maro, D; Le Dizès, S; Escobar-Gutiérrez, A; Voiseux, C; Solier, L; Hébert, D; Rozet, M; Cossonnet, C; Barillot, R

    2017-10-01

    Uncertainties remain regarding the fate of atmospheric tritium after it has been assimilated in grasslands (ryegrass) in the form of TFWT (Tissue Free Water Tritium) or OBT (Organically Bound Tritium). One such uncertainty relates to the tritium forms discrimination during transfer from TFWT to OBT resulting from photosynthesis (OBT photo ), corresponding to the OBT photo /TFWT ratio. In this study, the OBT/TFWT ratio is determined by experiments in the laboratory using a ryegrass model and hydroponic cultures, with constant activity of tritium in the form of tritiated water (denoted as HTO) in the "water" compartment (liquid HTO) and "air" compartment (HTO vapour in the air). The OBT photo /TFWT ratio and the exchangeable OBT fraction are measured for three parts of the plant: the leaf, seed and root. Plant growth is modelled using dehydrated biomass measurements taken over time in the laboratory and integrating physiological functions of the plant during the first ten days after germination. The results suggest that there is no measurable discrimination of tritium in the plant organic matter produced by photosynthesis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Performances of legume-grass mixtures under different cutting managements in mediterranean environments

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    Pasquale Martiniello

    2011-02-01

    Full Text Available Annual forage crops have great importance for sustaining animal production in southern Italy. Knowledge of the performance of legume-grass associations under management similar to systems encountered in farm practice is essential for their effective exploitation of the available environmental resources. The purpose of this investigation was to estimate the effects of five cutting managements on the productivity and botanical composition of ten annual fodder crop mixtures in two Mediterranean environments. Ten ternary combinations of one grass (Avena sativa L., oat and Lolium multiflorum Lam., Italian ryegrass, one clover (Trifolium alexandrinum L., berseem; Trifolium incarnatum L., crimson and Trifolium squarrosum L., squarrosum or burr medic (Medicago polymorpha L. and common vetch (Vicia sativa L. were compared in a field trial (split-plot design, 3 replicates in two locations (Cagliari and Foggia, Italy during the 2000-2001 growing season. The cutting treatments included a winter grazing simulation (G, a cutting only regime at early (EF or late flowering (F of legumes and a combination of treatments (GEF and GF. Plant density (no. m-2 prior to cutting, dry matter yield (g m-2 and botanical composition (% were evaluated. Considerable differences were observed in the harvestable dry matter yields of mixtures among cutting treatments in both localities, with treatment F showing the higher values (787.1 and 415.7 g m-2 for Cagliari and Foggia, respectively. The forage species were able to compete and establish good growth during their initial phase in both localities. However, the botanical composition between the two sites differed considerably after the winter period. Particularly, at Foggia, grass dominance was a permanent feature of all treatments, and all the mixtures contained about 84% of grass. Italian ryegrass was the most representative species under all treatments in both sites. Mixtures with Italian ryegrass, crimson or berseem

  14. Growth and Metal Accumulation of an Alyssum murale Nickel Hyperaccumulator Ecotype Co-cropped with Alyssum montanum and Perennial Ryegrass in Serpentine Soil

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    Catherine Leigh Broadhurst

    2016-04-01

    Full Text Available The genus Alyssum (Brassicaceae contains Ni hyperaccumulators (50, many of which can achieve 30 g kg-1 Ni in dry leaf. Some Alyssum hyperaccumulators are viable candidates for commercial Ni phytoremediation and phytomining technologies. It is not known whether these species secrete organic and/or amino acids into the rhizosphere to solubilize Ni, or can make use of such acids within the soil to facilitate uptake. It has been hypothesized that in fields with mixed plant species, mobilization of metals by phytosiderophores secreted by Graminaceae plants could affect Alyssum Ni, Fe, Cu and Mn uptake.We co-cropped the Ni hyperaccumulator Alyssum murale, non-hyperaccumulator A. montanum and perennial ryegrass in a natural serpentine soil. All treatments had standard inorganic fertilization required for ryegrass growth and one treatment was compost amended. After 4 months A. murale leaves and stems contained 3600 mg kg-1 Ni which did not differ significantly with co-cropping. Overall Ni and Mn concentrations were significantly higher in A. murale than in A. montanum or L. perenne. Copper was not accumulated by either Alyssum species, but L. perenne accumulated up to 10 mg kg-1. A. montanum could not compete with either A. murale or ryegrass, and neither Alyssum species survived in the compost-amended soil. Co-cropping with ryegrass reduced Fe and Mn concentrations in A. murale but not to the extent of either increasing Ni uptake or affecting plant nutrition. The hypothesized Alyssum Ni accumulation in response to phytosiderophores secreted by co-cropped grass did not occur. Our data do not support increased mobilization of Mn by a phytosiderophore mechanism either, but the converse: mobilization of Mn by the Alyssum hyperaccumulator species significantly increased Mn levels in L. perenne. Tilling soil to maximize root penetration, adequate inorganic fertilization and appropriate plant densities are more important for developing efficient

  15. Grazing ecology of female lambs on Italian ryegrass plus red clover pasture under different defoliation intensities Ecologia do pastejo por cordeiras em pastagem de azevém e trevo-vermelho sob diversas intensidades de desfolha

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    Carine Lisete Glienke

    2010-01-01

    Full Text Available The relationship between pasture dynamics and ingestive behavior of female lambs was studied on Italian ryegrass (Lolium multiflorum Lam. plus red clover (Trifolium pratense L. mixture under a range of defoliation intensities. Rotational grazing was used and the grazing interval was determined by the thermal sum of 313 degree days. The initial pre-grazing canopy height disappearance values were 65 (very high, 58 (high, 47 (medium and 37% (low. The sward vertical structure was similar among defoliation intensities. The forage allowance decreased linearly as defoliation intensities increased, with 0.35 bite/minute reduction for each 1% increase in forage allowance. The bite rate and number of bites/feeding station decreased with reduced contribution of leaves in the sward structure. It was associated, respectively, with an increase and a decrease of NDF and CP levels in forage as grazed by female lambs. The pasture cycle proves to be more important than defoliation intensities as a source for changes in feeding stations and displacement patterns of female lambs.Estudou-se a relação entre a dinâmica do pasto e o comportamento ingestivo de cordeiras em pastagem de azevém (Lolium multiflorum Lam. e trevo-vermelho (Trifolium pratense L. em diferentes intensidades de desfolha. O pastejo foi rotacionado e o intervalo entre pastejos foi determinado pela soma térmica de 313 graus-dia. Os valores de desaparecimento da altura do dossel no pré-pastejo foram de 65 (muito alta, 58 (alta, 47 (média e 37% (baixa, respectivamente. A estrutura vertical do pasto foi semelhante entre as intensidades de desfolha testadas. A oferta de forragem diminuiu linearmente com o aumento da intensidade de desfolha, com redução de 0,35 bocado/minuto a cada 1% a mais na oferta de forragem. A taxa de bocados e o número de bocados/estação alimentar reduziram com a diminuição da contribuição de folhas na estrutura da pastagem, acompanhada do aumento do teor de FDN e

  16. More milk from forage: Milk production, blood metabolites, and forage intake of dairy cows grazing pasture mixtures and spatially adjacent monocultures.

    Science.gov (United States)

    Pembleton, Keith G; Hills, James L; Freeman, Mark J; McLaren, David K; French, Marion; Rawnsley, Richard P

    2016-05-01

    There is interest in the reincorporation of legumes and forbs into pasture-based dairy production systems as a means of increasing milk production through addressing the nutritive value limitations of grass pastures. The experiments reported in this paper were undertaken to evaluate milk production, blood metabolite concentrations, and forage intake levels of cows grazing either pasture mixtures or spatially adjacent monocultures containing perennial ryegrass (Lolium perenne), white clover (Trifolium repens), and plantain (Plantago lanceolata) compared with cows grazing monocultures of perennial ryegrass. Four replicate herds, each containing 4 spring-calving, cross-bred dairy cows, grazed 4 different forage treatments over the periods of early, mid, and late lactation. Forage treatments were perennial ryegrass monoculture (PRG), a mixture of white clover and plantain (CPM), a mixture of perennial ryegrass, white clover, and plantain (RCPM), and spatially adjacent monocultures (SAM) of perennial ryegrass, white clover, and plantain. Milk volume, milk composition, blood fatty acids, blood β-hydroxybutyrate, blood urea N concentrations, live weight change, and estimated forage intake were monitored over a 5-d response period occurring after acclimation to each of the forage treatments. The acclimation period for the early, mid, and late lactation experiments were 13, 13, and 10 d, respectively. Milk yield (volume and milk protein) increased for cows grazing the RCPM and SAM in the early lactation experiment compared with cows grazing the PRG, whereas in the mid lactation experiment, milk fat increased for the cows grazing the RCPM and SAM when compared with the PRG treatments. Improvements in milk production from grazing the RCPM and SAM treatments are attributed to improved nutritive value (particularly lower neutral detergent fiber concentrations) and a potential increase in forage intake. Pasture mixtures or SAM containing plantain and white clover could be a

  17. Persistence of Overseeded Cool-Season Grasses in Bermudagrass Turf

    Directory of Open Access Journals (Sweden)

    Thomas Serensits

    2011-01-01

    Full Text Available Cool-season grass species are commonly overseeded into bermudagrass turf for winter color. When the overseeded grass persists beyond the spring; however, it becomes a weed. The ability of perennial ryegrass, Italian (annual ryegrass, intermediate ryegrass, and hybrid bluegrass to persist in bermudagrass one year after seeding was determined. Perennial ryegrass, intermediate ryegrass, and Italian ryegrass produced acceptable ground cover in the spring after fall seeding. Hybrid bluegrass did not establish well, resulting in unacceptable cover. Perennial ryegrass generally persisted the most one year after seeding, either because of summer survival of plants or because of new germination the following fall. Plant counts one year after seeding were greater in the higher seeding rate treatment compared to the lower seeding treatment rate of perennial ryegrass, suggesting new germination had occurred. Plant counts one year after seeding plots with intermediate ryegrass or Italian ryegrass were attributed primarily to latent germination and not summer survival. Applications of foramsulfuron generally did not prevent overseeded species stand one year after seeding, supporting the conclusion of new germination. Although quality is less with intermediate ryegrass compared to perennial ryegrass, it transitions out easier than perennial ryegrass, resulting in fewer surviving plants one year later.

  18. Elevated atmospheric carbon dioxide concentration: effects of increased carbon input in a Lolium perenne soil on microorganisms and decomposition

    NARCIS (Netherlands)

    Ginkel, van J.H.; Gorissen, A.; Polci, D.

    2000-01-01

    Effects of ambient and elevated atmospheric CO2 concentrations (350 and 700 μl l-1) on net carbon input into soil, the production of root-derived material and the subsequent microbial transformation were investigated. Perennial ryegrass plants (L. perenne L.) were labelled in a continuously labelled

  19. Efeito de fertilizantes minerais e orgânicos na produção de Azevém (Lolium multiflorum L.: produção de matéria seca e azoto aparentemente recuperado Effect of mineral and organic fertilizers in the ryegrass yield (Lolium multiflorum L.: Dry matter yield and apparent N recovery

    Directory of Open Access Journals (Sweden)

    M. Arrobas

    2009-01-01

    fertilizing materials were: chestnut fruit bark (CC, with 0.6% N, farmyard manure (EB, with 2.3% N, Beira Adubo (BA, a commercial organic amendment with 3% N; ammonium nitrate (NA, with 20.5% N; Entec (En, a fertiliser with a nitrification inhibitor, with 26% N; Fertigafsa (Fg a 4-16-12 compound fertiliser, and control (T without N fertilisation. All the fertilisers were applied at a rate equivalent to 200 mg N per kg of soil (< 2mm. A silt-loam soil with pH(H2O 5.2 and 27 g kg-1 of organic matter was used in the soil/fertiliser mixtures. A nutrient solution without N was added to all the pots. The crop was sown on the 1st October, 2004. After crop emergence, the plants were thinned to 50 plants per pot. Six harvests of ryegrass were taken between November 9, 2004 and August 4, 2005. Nitrogen uptake and apparent N recovery (NAR were also estimated after the determination of tissue N content. Total dry matter yields (6 cuts were significantly different between treatments. Extreme values ranged between 1.7 g/pot (T and 4.1 g/pot (NA. The higher N uptake was recorded in the NA treatment (167 mg N/pot, as well as the higher NAR (64%. Entec produced the lowest NAR (45% among the mineral fertilisers. The organic amendments BA and EB showed similar NAR, 24 and 22%, respectively. The N released from BA, EB and En during the growing season was very low. The results stress the difficulties in properly managing this kind of fertilisers in annual crops with short growing cycles, where a N shortage could occur during important phases of crop development.

  20. Development and mapping of DArT markers within the Festuca - Lolium complex

    DEFF Research Database (Denmark)

    Kopecký, David; Bartos, Jan; Lukaszewski, Adam J

    2009-01-01

    Background Grasses are among the most important and widely cultivated plants on Earth. They provide high quality fodder for livestock, are used for turf and amenity purposes, and play a fundamental role in environment protection. Among cultivated grasses, species within the Festuca-Lolium complex...... predominate, especially in temperate regions. To facilitate high-throughput genome profiling and genetic mapping within the complex, we have developed a Diversity Arrays Technology (DArT) array for five grass species: F. pratensis, F. arundinacea, F. glaucescens, L. perenne and L. multiflorum. Results The DAr...

  1. Functional and community-level soil microbial responses to zinc addition may depend on test system biocomplexity.

    Science.gov (United States)

    Sverdrup, Line E; Linjordet, Roar; Strømman, Gjermund; Hagen, Snorre B; van Gestel, Cornelis A M; Frostegård, Sa; Sørheim, Roald

    2006-12-01

    The effect of zinc on soil nitrification and composition of the microbial community in soil was investigated using a full factorial experiment with five zinc concentrations and four levels of biological complexity (microbes only, microbes and earthworms (Eisenia fetida), microbes and Italian ryegrass (Lolium multiflorum var. Macho), and microbes, ryegrass and earthworms). After 6 weeks of exposure, the activity of soil nitrifying bacteria was measured and the microbial community structure was characterized by phospholipid fatty acid (PLFA) analysis. Soil nitrification and several PLFA markers were significantly influenced by either zinc addition and/or the presence of earthworms or ryegrass, and one of the most pronounced changes was the increase of fungi and decrease of bacteria with increasing concentrations of zinc. Of particular interest, however, was the potential interaction between the presence of plants and/or earthworms and the effect of zinc, which the factorial study design allowed us to explore. Such an effect was observed in two cases: Earthworms reduced the positive effect of zinc on the fungal biomass (ANOVA, p=0.03), and the effect of earthworms on the soil nitrification activity depended on zinc concentration (ANOVA, p<0.05). The effect of earthworm presence was not very large, but it does show that multispecies tests might give information about metal toxicity or bioavailability that cannot be predicted from single-species tests.

  2. Novel Biochar-Plant Tandem Approach for Remediating Hexachlorobenzene Contaminated Soils: Proof-of-Concept and New Insight into the Rhizosphere.

    Science.gov (United States)

    Song, Yang; Li, Yang; Zhang, Wei; Wang, Fang; Bian, Yongrong; Boughner, Lisa A; Jiang, Xin

    2016-07-13

    Volatilization of semi/volatile persistent organic pollutants (POPs) from soils is a major source of global POPs emission. This proof-of-concept study investigated a novel biochar-plant tandem approach to effectively immobilize and then degrade POPs in soils using hexachlorobenzene (HCB) as a model POP and ryegrass (Lolium perenne L.) as a model plant growing in soils amended with wheat straw biochar. HCB dissipation was significantly enhanced in the rhizosphere and near rhizosphere soils, with the greatest dissipation in the 2 mm near rhizosphere. This enhanced HCB dissipation likely resulted from (i) increased bioavailability of immobilized HCB and (ii) enhanced microbial activities, both of which were induced by ryegrass root exudates. As a major component of ryegrass root exudates, oxalic acid suppressed HCB sorption to biochar and stimulated HCB desorption from biochar and biochar-amended soils, thus increasing the bioavailability of HCB. High-throughput sequencing results revealed that the 2 mm near rhizosphere soil showed the lowest bacterial diversity due to the increased abundance of some genera (e.g., Azohydromonas, Pseudomonas, Fluviicola, and Sporocytophaga). These bacteria were likely responsible for the enhanced degradation of HCB as their abundance was exponentially correlated with HCB dissipation. The results from this study suggest that the biochar-plant tandem approach could be an effective strategy for remediating soils contaminated with semi/volatile organic contaminants.

  3. Considerations for Managing Agricultural Co-Existence between Transgenic and Non-Transgenic Cultivars of Outcrossing Perennial Forage Plants in Dairy Pastures

    Directory of Open Access Journals (Sweden)

    Kevin F. Smith

    2016-11-01

    Full Text Available Many of the major forage species used in agriculture are outcrossing and rely on the exchange of pollen between individuals for reproduction; this includes the major species used for dairy production in grazing systems: perennial ryegrass (Lolium perenne L. and white clover (Trifolium repens L.. Cultivars of these species have been co-existing since contrasting cultivars were developed using plant breeding, but the consequences and need for strategies to manage co-existence have been made more prominent with the advent of genetic modification. Recent technological developments have seen the experimental evaluation of genetically modified (GM white clover and perennial ryegrass, although there is no current commercial growing of GM cultivars of these species. Co-existence frameworks already exist for two major cross-pollinated grain crops (canola and maize in Europe, and for alfalfa (Medicago sativa L. in the US, so many of the principles that the industry has developed for co-existence in these crops such as detection techniques, segregation, and agronomic management provide lessons and guidelines for outcrossing forage species, that are discussed in this paper.

  4. Application of molecular markers for variety protection of ryegrass (Lolium perenne L.)

    DEFF Research Database (Denmark)

    Jensen, Louise Bach; Deneken, Gerhard; Roulund, N

    2008-01-01

    registration systems. Although DUS testing currently employs mostly visually observable characteristics that are expressions of the phenotype of a variety, there is much interest in the use of molecular markers. The overall objective of this project is to examine the potential use of molecular markers...... with 140 alleles gives the same level of information. Furthermore, number of genotypes per variety can be reduced to 20 compared to the original dataset containing 60 genotypes when using all 18 SSR markers but not when using only six SSR markers. Significant association was found between the molecular...... on the morphological characterization from the DUS trial. 18 SSR markers were selected based on their genome distribution, reproducibility, level of information and ease of scoring. It was found, that for variety discrimination, reducing the number of SSR markers from 18 SSR markers with 262 alleles to six SSR markers...

  5. Grazing behaviour, intake, rumen function and milk production of dairy cows offered Lolium perenne containing different levels of water-soluble carbohydrates

    NARCIS (Netherlands)

    Taweel, H.Z.; Tas, B.M.; Smit, H.J.; Elgersma, A.; Dijkstra, J.; Tamminga, S.

    2006-01-01

    The aim of this study was to assess grazing behaviour, intake, rumen function, milk production and composition of dairy cows grazing perennial ryegrass varieties that were morphologically and chemically similar, but differed in their water-soluble carbohydrate (WSC) concentration. Eight multiparous

  6. Genomic prediction in a breeding program of perennial ryegrass

    DEFF Research Database (Denmark)

    Fé, Dario; Ashraf, Bilal; Greve-Pedersen, Morten

    2015-01-01

    We present a genomic selection study performed on 1918 rye grass families (Lolium perenne L.), which were derived from a commercial breeding program at DLF-Trifolium, Denmark. Phenotypes were recorded on standard plots, across 13 years and in 6 different countries. Variants were identified...... this set. Estimated Breeding Value and prediction accuracies were calculated trough two different cross-validation schemes: (i) k-fold (k=10); (ii) leaving out one parent combination at the time, in order to test for accuracy of predicting new families. Accuracies ranged between 0.56 and 0.97 for scheme (i....... A larger set of 1791 F2s were used as training set to predict EBVs of 127 synthetic families (originated from poly-crosses between 5-11 single plants) for heading date and crown rust resistance. Prediction accuracies were 0.93 and 0.57 respectively. Results clearly demonstrate considerable potential...

  7. Cross-species amplification of 105 Lolium perenne SSR loci in 23 species within the Poaceae

    DEFF Research Database (Denmark)

    Jensen, Louise Bach; Holm, Preben Bach; Lübberstedt, Thomas

    2007-01-01

    Amplification of 105 Lolium perenne SSR markers was studied in 23 grass species representing seven tribes from three subfamilies of Poaceae. Twelve of the SSR markers are published for the first time. Between 2% and 96% of the SSR markers could be amplified within a given species. A subset of eight...... SSR markers was evaluated for polymorphism across nine of the 23 grass species. Four to seven of the markers were polymorphic within each species, with an average detection of 2.4 alleles per species....

  8. [Effect of Ryegrass and Arbuscular Mycorrhizal on Cd Absorption by Varieties of Tomatoes and Cadmium Forms in Soil].

    Science.gov (United States)

    Chen, Yong-qin; Jiang, Ling; Xu, Wei-hong; Chi, Sun-lin; Chen, Xu-gen; Xie, Wen-wen; Xiong, Shi- juan; Zhang, Jin-zhong; Xiong, Zhi-ting

    2015-12-01

    Field trial was carried out to investigate the effects of ryegrass and arbuscular mycorrhizal single or compound treatment to two varieties of tomato ("Defu mm-8" and "Luobeiqi") on the plant growth, concentrations and accumulations of Cd as well as the impact on microorganisms, enzyme activities, pH and Cd forms in soil when exposed to Cd (5.943 mg · kg⁻¹). The results showed that dry weights of fruit, root, stem, leaf and plant significantly increased by single or compound treatment of ryegrass and arbuscular mycorrhizal by 14.1%-38.4% and 4.2%-18.3%, 20.9%-31.5% and 8.4%-10.3%, 13.0%-16.8% and 3.0%-9.5%, 10.7%- 16.8% and 2.7%-7.6%, 14.3%-36.6% and 4.5%-16.8%, respectively. The amounts of bacteria, fungi, actinomycetes of soil and the activities of urease, invertase, acid phosphatase, catalase in soil were increased by single or compound treatment of ryegrass and arbuscular mycorrhizal, and the soil microorganism amounts and enzyme activities significantly differed between the two varieties of tomato and treatments (P arbuscular mycorrhizal, while the concentrations of EXC-Cd, CAB-Cd, Fe-Mn-Cd and total Cd in soil were decreased, and the total Cd content was decreased by 16.9%-27.8%. Cadmium concentrations in fruit, leaf, stem and root of both varieties were significantly decreased by 6.9%-40.9%, 5.7%-40.1%, 4.6%-34.7% and 9.8%-42.4%, respectively. Cadmium accumulations in tomato were in order of leaf > stem > root > fruit. Comparing the two tomato varieties, Cd concentrations and Cd accumulations in fruit and plant were in order of "Luobeiqi" arbuscular mycorrhizal.

  9. A Gene Encoding a DUF247 Domain Protein Cosegregates with the S Self-Incompatibility Locus in Perennial Ryegrass

    DEFF Research Database (Denmark)

    Manzanares, Chloe; Barth, Susanne; Thorogood, Daniel

    2016-01-01

    genes cosegregating with the S-locus, a highly polymorphic gene encoding for a protein containing a DUF247 was fully predictive of known S-locus genotypes at the amino acid level in the seven mapping populations. Strikingly, this gene showed a frameshift mutation in self-compatible darnel (Lolium...

  10. Effect of herbicides on desiccation of Lolium multiflorum L. plants and seed germinationEfeito de herbicidas na dessecação e germinação de sementes remanescentes de Lolium multiflorum L.

    Directory of Open Access Journals (Sweden)

    Caio Ferraz de Campos

    2012-12-01

    Full Text Available A trial was carried out to evaluate efficacy of different herbicides and spray volumes when sprayed to ryegrass for chemical management and control of remaining seeds. The treatments were: three formulations of glyphosate at 1080 g ha-1 (Original Round up, Round up Transorb, WG Round Up, paraquat + diuron at 300+500 and 150+250 g ha-1 and glufosinate ammonium at 400 and 600 g ha-1. All treatments were used in spray volumes of 200 and 400 l ha-1. The effectiveness of the desiccation of ryegrass plants was assessed at 1, 3, 7, 14 and 21 days after application. At the last evaluation samples were collected for dry mass production analysis, and also panicles with seeds for germination test. Glyphosate in different formulations and volumes and glufosinate ammonium at 600 g ha-1 when sprayed with into 400 l ha-1 provided the best controls regarding ryegrass chemical management. Treatments with gliphosate (Roundup Original and paraquat + diuron (300 +150 g ha-1 in volumes of 400 and 200 L ha-1, respectively, were the ones that showed the lowest values of dry matter, differing from the control. All the ryegrass seeds were killed by treatments with herbicides (paraquat + diuron at 500 +250 g ha-1 and glufosinate-ammonium at 600 g ha-1 when used 200 l ha-1. O objetivo desse trabalho foi o de avaliar a eficácia de diferentes herbicidas aplicados em pósemergência na dessecação de plantas de azevém e viabilidade de sementes remanescentes do controle, com diferentes volumes de calda de aplicação. Os tratamentos testados foram: três formulações de glyphosate na dose de 1.080g ha-1 (Roundup Original, Roundup Transorb, Roundup WG, paraquat + diuron nas doses de 300 + 150 e 500 + 250g ha-1 e amônio-glufosinate nas doses de 400 e 600g ha-1. Em todos os tratamentos foram utilizados os volumes de aplicação de 200 e 400L ha-1. A eficácia na dessecação de plantas de azevém foram avaliados aos 1, 3, 7, 14 e 21 dias após aplicação, sendo que nesta

  11. Distribution of copper and other elements in ryegrass roots, determined with a scanning proton microprobe

    International Nuclear Information System (INIS)

    Mazzolini, A.P.; Legge, G.J.F.

    1982-01-01

    A scanning proton microprobe has been used to determine the distribution of Cu and other elements in Wimmera ryegrass roots grown in solution cultures. Cu was found to be localized on or near the surface of the roots in randomly distributed discrete zones. The distribution of Cu was partially correlated with those of Fe, P and Ca and possibly indicates some form of association; co-precipitation in a precipitate of ferric phosphate or hydroxy-oxide is favoured

  12. A study of the wet deposit and foliar uptake of iodine and strontium on rye-grass and clover

    International Nuclear Information System (INIS)

    Angeletti, Livio; Levi, Emilio; Commission of the European Communities, Ispra

    1977-12-01

    Foliar uptake of iodine and strontium by rye-grass and clover was studied as a function of aspersion intensities. At the same time, the contribution of root sorption to foliar uptake was measured. The effective half-lives of radionuclides of standing and harvested grass were also determined together with their uptake under the action of demineralized water aspersion [fr

  13. Selenium bioavailability and uptake as affected by four different plants in a loamy clay soil with particular attention to mycorrhizae inoculated ryegrass

    International Nuclear Information System (INIS)

    Munier-Lamy, C.; Deneux-Mustin, S.; Mustin, C.; Merlet, D.; Berthelin, J.; Leyval, C.

    2007-01-01

    The aim of this study was to investigate the influence of plant species, especially of their rhizosphere soil, and of inoculation with an arbuscular mycorrhizal (AM) fungus on the bioavailability of selenium and its transfer in soil-plant systems. A pot experiment was performed with a loamy clay soil and four plant species: maize, lettuce, radish and ryegrass, the last one being inoculated or not with an arbuscular mycorrhizal fungus (Glomus mosseae). Plant biomass and Se concentration in shoots and roots were estimated at harvest. Se bioavailability in rhizosphere and unplanted soil was evaluated using sequential extractions. Plant biomass and selenium uptake varied with plant species. The quantity of rhizosphere soil also differed between plants and was not proportional to plant biomass. The highest plant biomass, Se concentration in plants, and soil to plant transfer factor were obtained with radish. The lowest Se transfer factors were obtained with ryegrass. For the latter, mycorrhizal inoculation did not significantly affect plant growth, but reduced selenium transfer from soil to plant by 30%. In unplanted soil after 65 days aging, more than 90% of added Se was water-extractable. On the contrary, Se concentration in water extracts of rhizosphere soil represented less than 1% and 20% of added Se for ryegrass and maize, respectively. No correlation was found between the water-extractable fraction and Se concentration in plants. The speciation of selenium in the water extracts indicated that selenate was reduced, may be under organic forms, in the rhizosphere soil

  14. Effect of Winter Cover Crops on Soil Nitrogen Availability, Corn Yield, and Nitrate Leaching

    Directory of Open Access Journals (Sweden)

    S. Kuo

    2001-01-01

    Full Text Available Biculture of nonlegumes and legumes could serve as cover crops for increasing main crop yield, while reducing NO3 leaching. This study, conducted from 1994 to 1999, determined the effect of monocultured cereal rye (Secale cereale L., annual ryegrass (Lolium multiflorum, and hairy vetch (Vicia villosa, and bicultured rye/vetch and ryegrass/vetch on N availability in soil, corn (Zea mays L. yield, and NO3-N leaching in a silt loam soil. The field had been in corn and cover crop rotation since 1987. In addition to the cover crop treatments, there were four N fertilizer rates (0, 67, 134, and 201 kg N ha-1, referred to as N0, N1, N2, and N3, respectively applied to corn. The experiment was a randomized split-block design with three replications for each treatment. Lysimeters were installed in 1987 at 0.75 m below the soil surface for leachate collection for the N0, N2, and N3 treatments. The result showed that vetch monoculture had the most influence on soil N availability and corn yield, followed by the bicultures. Rye or ryegrass monoculture had either no effect or an adverse effect on corn yield and soil N availability. Leachate NO3-N concentration was highest where vetch cover crop was planted regardless of N rates, which suggests that N mineralization of vetch N continued well into the fall and winter. Leachate NO3-N concentration increased with increasing N fertilizer rates and exceeded the U.S. Environmental Protection Agency’s drinking water standard of 10 mg N l�1 even at recommended N rate for corn in this region (coastal Pacific Northwest. In comparisons of the average NO3-N concentration during the period of high N leaching, monocultured rye and ryegrass or bicultured rye/vetch and ryegrass/vetch very effectively decreased N leaching in 1998 with dry fall weather. The amount of N available for leaching (determined based on the presidedress nitrate test, the amount of N fertilizer applied, and N uptake correlated well with average NO3

  15. Effect of winter cover crops on soil nitrogen availability, corn yield, and nitrate leaching.

    Science.gov (United States)

    Kuo, S; Huang, B; Bembenek, R

    2001-10-25

    Biculture of nonlegumes and legumes could serve as cover crops for increasing main crop yield, while reducing NO3 leaching. This study, conducted from 1994 to 1999, determined the effect of monocultured cereal rye (Secale cereale L.), annual ryegrass (Lolium multiflorum), and hairy vetch (Vicia villosa), and bicultured rye/vetch and ryegrass/vetch on N availability in soil, corn (Zea mays L.) yield, and NO3-N leaching in a silt loam soil. The field had been in corn and cover crop rotation since 1987. In addition to the cover crop treatments, there were four N fertilizer rates (0, 67, 134, and 201 kg N ha(-1), referred to as N0, N1, N2, and N3, respectively) applied to corn. The experiment was a randomized split-block design with three replications for each treatment. Lysimeters were installed in 1987 at 0.75 m below the soil surface for leachate collection for the N 0, N 2, and N 3 treatments. The result showed that vetch monoculture had the most influence on soil N availability and corn yield, followed by the bicultures. Rye or ryegrass monoculture had either no effect or an adverse effect on corn yield and soil N availability. Leachate NO3-N concentration was highest where vetch cover crop was planted regardless of N rates, which suggests that N mineralization of vetch N continued well into the fall and winter. Leachate NO3-N concentration increased with increasing N fertilizer rates and exceeded the U.S. Environmental Protection Agency's drinking water standard of 10 mg N l(-1) even at recommended N rate for corn in this region (coastal Pacific Northwest). In comparisons of the average NO3-N concentration during the period of high N leaching, monocultured rye and ryegrass or bicultured rye/vetch and ryegrass/vetch very effectively decreased N leaching in 1998 with dry fall weather. The amount of N available for leaching (determined based on the presidedress nitrate test, the amount of N fertilizer applied, and N uptake) correlated well with average NO3-N during

  16. Update On The Development Of DArT Markers And 454-Sequencing In Festuca/Lolium And Phleum

    DEFF Research Database (Denmark)

    Sandve, Simen R; Bartos, Jan; Kopecky, David

    Development of genomic resources in perennial grasses for high-throughput applications in genomic research and plant breeding has lagged behind most other crops. The predicted climate changes create novel patterns of biotic and abiotic stresses. Efficient characterization and utilization of genetic...... resources for developing improved cultivars adapted to the future climates depend on modern genomic resources. We will describe our recent activity in developing genomic resources for Festuca/Lolium and Phleum. These resources include the development and mapping of DArT-markers in Festuca pratensis...

  17. Phytoextraction of Heavy Metals from Soil Polluted with Waste Mining by Using Forage Plants in Successive Cultures

    Directory of Open Access Journals (Sweden)

    Anca Pricop

    2010-10-01

    Full Text Available During two years, was studied the phytoextraction potential of some perennial species (Medicago sativa and Trifolium pretense, Festuca arundinacea and Lolium perenne, for Zn, Cd, and Pb from soils polluted with waste mining. The experiment was done on kernozem soil with adding of 20 kg waste mining/m2 and 8 kg biosolid/m2. The results showed that in all experiments, rye-grass is a good extractor for Zn and Cd, and leguminous species for Pb. Both leguminous species, especially M. sativa, presented a high tolerance for lead toxicity, even with 3-4 times greater values than maximum allowable level from actual legislation. In all cases, regardless of the experimental variant, raygrass (Lolium perenne is a good accumulator of Zn and Cd, and red clover (Trifolium pratense of Pb. The values of metal bioaccumulation increase gradually with their concentration in soil. Quality of very good extractor of Pb displayed by Trifolium pratense species are kept even in case of excessive pollution with Pb, when it exceed 3.4 times the maximum permissible norms. This proves, as Medicago sativa species, a good tolerance and resistance to toxicity of this metal. In case of addition of natural zeolite-volcanic tuff there was no increase in the rate of Zn bioaccumulation. Only in case of Cd at Lolium perenne and Pb at Trifolium pratense appear the favourable effect of metallic ions bioavailability in soil for plants.

  18. Análisis de la sensibilidad de biotipos de Lolium multiflorum a herbicidas inhibidores de la enzima ALS, ACCasa y Glifosato Sensitivity analysis of Lolium multiflorum biotypes to Glyphosate, ACCase and ALS-inhibiting herbicides

    Directory of Open Access Journals (Sweden)

    P. Diez De Ulzurrun

    2012-09-01

    Full Text Available A pesar de los avances logrados en el control de las malezas con el uso de herbicidas, el manejo de las mismas no se simplificó, sino que, al contrario, surgieron nuevos desafíos, como la aparición de resistencia a herbicidas. En 2007, se reportó en Lolium multiflorum el segundo caso de resistencia a glifosato detectado en Argentina. En el sudeste de la provincia de Buenos Aires se registraron fallas de control a campo en poblaciones de Lolium multiflorum debido a su resistencia a distintos herbicidas de las familias de los inhibidores de ALS y de ACCasa y al herbicida glifosato. El objetivo de este estudio fue caracterizar el nivel de resistencia a ciertos herbicidas inhibidores de la ALS y de la ACCasa y al glifosato en una población de L. multiflorum de Lobería (Bs As, Argentina supuestamente resistente (LmR. Se realizaron bioensayos en cajas de Petri y se determinó la GR50 mediante la variación en la longitud de coleoptile. Las curvas de dosis-respuesta se obtuvieron por medio de la ecuación log-logística. El biotipo LmR presentó resistencia múltiple a herbicidas con tres modos de acción diferentes: glifosato, inhibidores de ALS y de ACCasa. Dicho ensayo demostró la aparición de un biotipo de L. multiflorum con resistencia a múltiples principios activos.Despite progress in weed control using herbicides, management has not been simplified, but new challenges such as herbicides resistance have arisen. In 2007, a Lolium multiflorum population resistant to glyphosate was reported, as the second case of glyphosate resistant weeds in Argentina. In the southeast of Buenos Aires province, control failures in populations of L. multiflorum to different families of herbicide such as ALS and ACCase inhibitors and to glyphosate at field level have been registered. The aim of this study was to characterize the level of resistance to certain herbicides inhibitors of ALS, ACCase and glyphosate in a putatively resistant (LmR population of L

  19. Complementary effects of red clover inclusion in ryegrass-white clover swards for grazing and cutting

    DEFF Research Database (Denmark)

    Eriksen, Jørgen; Askegaard, Margrethe; Søegaard, Karen

    2014-01-01

    Increasing plant species diversity in grasslands may improve productivity and stability of yields. In a field experiment, we investigated the herbage dry-matter (DM) yield and crude protein content of two-species swards of perennial ryegrass–white clover (Lolium perenne L.–Trifolium repens L...... clover in sown swards are discussed. These may include higher nitrogen-use efficiency in ruminants, increased soil fertility and improved sward flexibility to cope with changing managements. The findings also suggest positive yield effects of alternating between cutting and grazing within the season...

  20. THE EFFECT OF SOIL CONDITIONERS ON CELLULOSE, HEMICELLULOSE, AND THE ADL FIBRE FRACTION CONCENTRATION IN DACTYLIS GLOMERATA AND LOLIUM PERENNE

    Directory of Open Access Journals (Sweden)

    Milena Truba

    2017-01-01

    Full Text Available Replicated three times, the research was conducted in the experimental field between 2011 and 2014. Three soil conditioners with the following trade names: UGmax, Eko-Użyźniacz, and Humus Active Papka were used in the experiment, separately or together with NPK fertilisers. They were all used on plots sown with two species of grass, Dactylis glomerata of the Bora variety and Lolium perenne of the Info variety. The plant material from both grass species was tested for the concentration of ADL fraction (% DM, cellulose (% DM, and hemicellulose (% DM. It was found that the concentration of cellulose, hemicelluloses, and the ADL fraction was significantly higher in the biomass of Dactylis glomerata than in the biomass of Lolium perenne. The grass from the plot with the UGmax soil conditioner applied had the highest amount of cellulose and hemicellulose. The lowest amount of those organic compounds was found in the grass treated with UGmax together with mineral fertilisers and in plants treated with Humus Active, together with mineral fertilisers. However, the fertilisers and conditioners did not increase the ADL content in both grass species.

  1. Soil Properties and Plant Biomass Production in Natural Rangeland Management Systems

    Directory of Open Access Journals (Sweden)

    Romeu de Souza Werner

    Full Text Available ABSTRACT Improper management of rangelands can cause land degradation and reduce the economic efficiency of livestock activity. The aim of this study was to evaluate soil properties and quantify plant biomass production in four natural rangeland management systems in the Santa Catarina Plateau (Planalto Catarinense of Brazil. The treatments, which included mowed natural rangeland (NR, burned natural rangeland (BR, natural rangeland improved through the introduction of plant species after harrowing (IH, and natural rangeland improved through the introduction of plant species after chisel plowing (IC, were evaluated in a Nitossolo Bruno (Nitisol. In the improved treatments, soil acidity was corrected, phosphate fertilizer was applied, and intercropped annual ryegrass (Lolium multiflorum, velvet grass (Holcus lanatus, and white clover (Trifolium repens were sown. Management systems with harrowed or chisel plowed soil showed improved soil physical properties; however, the effect decreased over time and values approached those of burned and mowed natural rangelands. Natural rangeland systems in the establishment phase had little influence on soil organic C. The mowed natural rangeland and improved natural rangeland exhibited greater production of grazing material, while burning the field decreased production and increased the proportion of weeds. Improvement of the natural rangelands increased leguminous biomass for pasture.

  2. Phytotoxic Effects and a Phytotoxin from the Invasive Plant Xanthium italicum Moretti

    Directory of Open Access Journals (Sweden)

    Hua Shao

    2012-04-01

    Full Text Available The allelopathic effects of different parts of the plant Xanthium italicum Moretti were evaluated by conducting bioassays against two dicot plants, amaranth (Amaranthus mangostanus L. and lettuce (Lectuca sativa L., and two monocot plants, wheat (Triticum aestivum Linn and ryegrass (Lolium multiforum. Leaf and fruit extract possessed the strongest biological activity, killing all seeds of four test species at 0.05 g/mL concentration. Fruits were chosen for further investigation because of their high biomass. This led to the isolation and identification of a phytotoxin—Xanthinosin—a known sesquiterpene lactone. Xanthinosin significantly affected seedling growth of all test species at 160 µM concentration. Cultivating seeds in 800 μM xanthinosin solution resulted in a great decrease in seedling growth of all test species, especially for the two dicot plants, amaranth and lettuce, whose root length was inhibited by 78% and 89%, respectively. By comparison, the numbers were 69% lower for wheat, and 66% for ryegrass, two monocot plants. When treated with 4 mM xanthinosin solution, seed germination of all test plants was almost completely inhibited. The possibility of utilizing xanthinosin as an eco-friendly herbicide was discussed.

  3. A study of the human immune response to Lolium perenne (rye) pollen and its components, Lol p I and Lol p II (Rye I and Rye II). II. Longitudinal variation of antibody levels in relation to symptomatology and pollen exposure and correction of seasonally elevated antibody levels to basal values.

    Science.gov (United States)

    Freidhoff, L R; Ehrlich-Kautzky, E; Meyers, D A; Marsh, D G

    1987-11-01

    This study used a standardized, dialyzed, Lolium perenne (ryegrass) pollen extract and two of its well-characterized components, Lol p I (Rye I) and Lol p II (Rye II), to characterize the longitudinal variation of both IgE and IgG antibody (Ab) levels, as well as total serum IgE levels, in 20 grass-allergic subjects followed for 13 months. Ab levels declined toward a basal level just before, and increased just after, the grass-pollination season, returning to the same basal level just before the next grass-pollination season. The least complex allergen, Lol II, demonstrated the most uniform pattern of variation in both IgE and IgG Ab levels. Total serum IgE levels demonstrated the least regular pattern of variation. Grass-pollen counts were strongly correlated with symptom-medication scores for these subjects (rs = 0.87). Initial values were correlated with the rise in total IgE and IgE Ab to Lol II across the grass-pollen season. Skin test results were correlated with initial IgE Ab levels for L. perenne pollen extract and Lol II. Finally, a procedure for correcting IgE Ab levels to basal values was proposed and tested. The correction procedure, for each IgE Ab, was based on the average rise during the grass-pollination season (or average decline after the grass-pollination season) observed for all subjects with that IgE Ab.

  4. Prevalence of quinolone resistance genes, copper resistance genes, and the bacterial communities in a soil-ryegrass system co-polluted with copper and ciprofloxacin.

    Science.gov (United States)

    Tuo, Xiaxia; Gu, Jie; Wang, Xiaojuan; Sun, YiXin; Duan, Manli; Sun, Wei; Yin, Yanan; Guo, Aiyun; Zhang, Li

    2018-04-01

    The presence of high concentrations of residual antibiotics and antibiotic resistance genes (ARGs) in soil may pose potential health and environmental risks. This study investigated the prevalence of plasmid-mediated quinolone resistance (PMQR) genes, copper resistance genes (CRGs), and the bacterial communities in a soil-ryegrass pot system co-polluted with copper and ciprofloxacin (CIP; 0, 20, or 80 mg kg -1 dry soil). Compared with the samples on day 0, the total relative abundances of the PMQR genes and mobile genetic elements (MGEs) were reduced significantly by 80-89% in the ryegrass and soil by the cutting stage (after 75 days). The abundances of PMQR genes and MGEs were reduced by 63-81% in soil treated with 20 mg kg -1 CIP compared with the other treatments, but the abundances of CRGs increased by 18-42%. The presence of 80 mg kg -1 CIP affected the microbial community structure in the soil by increasing the abundances of Acidobacteria and Thaumarchaeota, but decreasing those of Firmicutes. Redundancy analysis indicated that the pH and microbial composition were the main factors that affected the variations in PMQR genes, MGEs, and CRGs, where they could explain 42.2% and 33.3% of the variation, respectively. Furthermore, intI2 may play an important role in the transfer of ARGs. We found that 80 mg kg -1 CIP could increase the abundances of ARGs and CRGs in a soil-ryegrass pot system. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Grazing management and supplementation effects on forage and dairy cow performance on cool-season pastures in the southeastern United States.

    Science.gov (United States)

    Macoon, B; Sollenberger, L E; Staples, C R; Portier, K M; Fike, J H; Moore, J E

    2011-08-01

    Cool-season annual forages provide high-quality herbage for up to 5 mo in the US Gulf Coast states, but their management in pasture-based dairy systems has received little attention. Objectives of this study were to evaluate pasture and animal responses when lactating Holstein cows (n=32, mean DIM=184±21) grazed either N-fertilized rye (Secale cereale L.)-annual ryegrass (Lolium multiflorum Lam.) mixed pastures or rye-annual ryegrass-crimson clover (Trifolium incarnatum L.)-red clover (Trifolium pratense L.) pastures at 2 stocking rates (5 vs. 2.5 cows/ha) and 2 rates of concentrate supplementation [0.29 or 0.40 kg of supplement (as is)/kg of daily milk production]. Two cows paired by parity (one multiparous and one primiparous) were assigned randomly to each pasture. The 2 × 2 × 2 factorial arrangement of treatments was replicated twice in a completely randomized design. Forage mixture and supplementation rate did not affect milk production during three 28-d periods. Greater milk production occurred at the low (19.7 kg/d) than the high (14.7 kg/d) stocking rate during periods 2 and 3, but production was similar during period 1. Despite lower production per cow, milk production per hectare was generally greater at the high stocking rate (81.6 vs. 49.5 kg/ha). Generally, greater pregraze herbage mass on pastures at the lower stocking rate (1,400 vs. 1,150 kg/ha) accounted for greater herbage allowance. Both forage (8.0 vs. 5.9 kg/d) and total (14.1 vs. 11.6) organic matter intake were greater at the low stocking rate. Cows fed less supplement had greater forage organic matter intake (8.0 vs. 6.1 kg/d). Greater herbage mass was associated with the greater intake and subsequent greater milk production. Differences in forage nutritive value, blood metabolites and milk composition, although showing some response to treatments, may not be of sufficient magnitude to affect choice of pasture species or other management practices. Animal performance was not improved by

  6. Coordinated nitrogen and carbon remobilization for nitrate assimilation in leaf, sheath and root and associated cytokinin signals during early regrowth of Lolium perenne

    Czech Academy of Sciences Publication Activity Database

    Roche, J.; Turnbull, M. H.; Guo, Q.; Novák, Ondřej; Späth, J.; Gieseg, S. P.; Jameson, P. E.; Love, J.

    2017-01-01

    Roč. 119, č. 8 (2017), s. 1353-1364 ISSN 0305-7364 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : assimilation * cytokinin * defoliation * Lolium perenne * nitrate * Nitrogen * regrowth * water-soluble carbohydrates Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Plant sciences, botany Impact factor: 4.041, year: 2016

  7. Life cycle inventory and risk assessment of genetic modified perennial ryegrass in a technology foresight perspective

    DEFF Research Database (Denmark)

    Borch, K.; Rasmussen, B.; Schleisner, L.

    2000-01-01

    important and uncertain fac-tors for the future direction of GM crops: 1) publicparticipation in regulation, 2) utility value for the consumers, 3) being first to market GM-ryegrass, and 4) an efficient professional network. Based on the identified drivers several scenar-ios were constructed, of which two......, a methodological approach is suggested to analyse the uncertainties that the biotech industry and the authorities face when implementing genetically modified (GM) crops. These uncertainties embracescientific rationality regarding technological development and risk assessments, as well as ethic political and social...

  8. Isolating and evaluating lactic acid bacteria strains for effectiveness on silage quality at low temperatures on the Tibetan Plateau.

    Science.gov (United States)

    Wang, Siran; Yuan, Xianjun; Dong, Zhihao; Li, Junfeng; Shao, Tao

    2017-11-01

    Four lactic acid bacteria (LAB) strains isolated from straw silages on the Tibetan Plateau were characterized, and their effects on the fermentation quality of Italian ryegrass (Lolium multiflorum Lam.) at different temperatures (10°C, 15°C and 25°C) were studied. These LAB isolates were evaluated using the acids production ability test, morphological observation, Gram staining, physiological, biochemical and acid tolerance tests. All the isolates (M1, LM8, LO7 and LOG9) could grow at 5-20°C, pH 3.5-7.0 and NaCl (3.0%, 6.5%). Strains M1, LM8, LO7 and LOG9 were identified as Lactobacillus plantarum, L. coryniformis, Pediococcus pentosaceus and P. acidilactici, respectively, by sequencing 16S ribosomal DNA. The four isolates were added to Italian ryegrass for ensiling for 30 days at various temperatures. Compared with the corresponding control, inoculating with isolates M1, LM8 and LO7 could improve the silage quality of Italian ryegrass at low temperatures, indicated by significantly (P lactic acid (LA) contents and ratios of lactic acid/acetic acid (LA/AA), and significantly (P < 0.05) lower pH and ammonia nitrogen/total nitrogen (AN/TN). Compared with other isolates, LM8 performed better at 10°C and 15°C, indicated by the higher (P < 0.05) LA content and ratio of LA/AA, and the lower (P < 0.05) pH and AN/TN. © 2017 Japanese Society of Animal Science.

  9. Flowering catch crops used as forage plants for dairy cows: influence on fatty acids and tocopherols in milk.

    Science.gov (United States)

    Kälber, T; Meier, J S; Kreuzer, M; Leiber, F

    2011-03-01

    The effect of several flowering dicotyledonous catch crop plants (dicots) on milk fat quality in cows was investigated to test the hypothesis that their phenolic compounds may inhibit ruminal biohydrogenation and thus enhance the transfer to milk of intact, plant-derived polyunsaturated fatty acids. Berseem clover (Trifolium alexandrinum), buckwheat (Fagopyrum esculentum), and phacelia (Phacelia tanacetifolia) were sown in mixture with ryegrass (Lolium multiflorum; intended biomass proportion of 0.2) on 1ha. For comparison, nonflowering chicory (Cichorium intybus, also sown in mixture with ryegrass) and pure ryegrass were cultivated. Realized biomass proportions (wet weight) were 91% for berseem clover, 69% for buckwheat, 54% for phacelia, and 51% for chicory. At the start of flowering (or from d 47 after sowing onward), cultures were harvested daily and fed for 20 d ad libitum to groups of 6 midlactation cows each. Additionally, 1 kg each of energy and protein concentrate and pure ryegrass hay were fed. Individual intake and milk yield of the cows were measured daily. Milk samples were obtained twice daily 5 d before and from 11 to 20 d after the start of treatment feeding. Feed samples were drawn twice a week from the fresh feeds. Apart from standard traits, feeds and milk were analyzed for fatty acids, tocopherols, and phenolic fractions. Only a few substantial treatment effects on intake and performance were observed. All diets based on dicots increased α-linolenic acid (ALA) concentrations in milk fat compared with the ryegrass diet even though the corresponding swards were not generally richer in ALA. The highest ALA concentration in milk fat (1.3 g/100g of fatty acids) occurred with the berseem clover diet. Transfer rate of ALA from feed to milk was highest with the buckwheat diet (0.09) and lowest with ryegrass (0.05). This was congruent with the differences in total extractable phenols, being high in the buckwheat sward (2.6% of dry matter) and low in the

  10. Effects of biochars on the availability of heavy metals to ryegrass in an alkaline contaminated soil.

    Science.gov (United States)

    Zhang, Guixiang; Guo, Xiaofang; Zhao, Zhihua; He, Qiusheng; Wang, Shuifeng; Zhu, Yuen; Yan, Yulong; Liu, Xitao; Sun, Ke; Zhao, Ye; Qian, Tianwei

    2016-11-01

    A pot experiment was conducted to investigate the effects of biochars on the availability of heavy metals (Cd, Cu, Mn, Ni, Pb, and Zn) to ryegrass in an alkaline contaminated soil. Biochars only slightly decreased or even increased the availability of heavy metals assesses by chemical extractant (a mixture of 0.05 mol L -1 ethylenediaminetetraacetic acid disodium, 0.01 mol L -1 CaCl 2 , and 0.1 mol L -1 triethanolamine). The significantly positive correlation between most chemical-extractable heavy metals and the ash content in biochars indicated the positive role of ash in this extraction. Biochars significantly reduced the plant uptake of heavy metals, excluding Mn. The absence of a positive correlation between the chemical-extractable heavy metals and the plant uptake counterparts (except for Mn) indicates that chemical extractability is probably not a reliable indicator to predict the phytoavailability of most heavy metals in alkaline soils treated with biochars. The obviously negative correlation between the plant uptake of heavy metals (except for Mn) and the (O + N)/C and H/C indicates that biochars with more polar groups, which were produced at lower temperatures, had higher efficiency for reducing the phytoavailability of heavy metals. The significantly negative correlations between the plant uptake of Mn and ryegrass biomass indicated the "dilution effect" caused by the improvement of biomass. These observations will be helpful for designing biochars as soil amendments to reduce the availability of heavy metals to plants in soils, especially in alkaline soils. Copyright © 2016. Published by Elsevier Ltd.

  11. Cloning and sequencing of Lol pI, the major allergenic protein of rye-grass pollen.

    Science.gov (United States)

    Griffith, I J; Smith, P M; Pollock, J; Theerakulpisut, P; Avjioglu, A; Davies, S; Hough, T; Singh, M B; Simpson, R J; Ward, L D

    1991-02-25

    We have isolated a full length cDNA clone encoding the major glycoprotein allergen Lol pI. The clone was selected using a combination of immunological screening of a cDNA expression library and PCR amplification of Lol pI-specific transcripts. Lol pI expressed in bacteria as a fusion protein shows recognition by specific IgE antibodies present in sera of grass pollen-allergic subjects. Northern analysis has shown that the Lol pI transcripts are expressed only in pollen of rye-grass. Molecular cloning of Lol pI provides a molecular genetic approach to study the structure-function relationship of allergens.

  12. Effect of four acidifying materials added to a calcareous soil on the availability of phosphorus to ryegrass

    Energy Technology Data Exchange (ETDEWEB)

    Sen Gupta, M B; Cornfield, A H

    1964-12-01

    Ryegrass was grown in a pot test using a calcareous soil (0.36% calcium carbonate) treated with sulfur, ammonium sulfate, ferrous sulfate, and aluminium sulfate at 0.1% sulfur-equivalent, with potassium nitrate added where necessary, including the control, to equalize nitrogen supply. The sulfur treatment was the only one which significantly increased dry matter yields, total phosphorus uptake and top/root ratios in dry matter yields and total phosphorus. The ammonium sulfate, ferrous sulfate, and aluminium sulfate treatments significantly reduced top/root ratios in dry-matter yields and total phosphorus. 6 references, 1 table.

  13. Effect of Weather on the Occurrence of Puccinia Graminis Subsp. Graminicola and Puccinia Coronata F. Sp. Lolii at Lolium Perenne L. and Deschampsia Caespitosa (L. P. B.

    Directory of Open Access Journals (Sweden)

    Monika Novotná

    2017-01-01

    Full Text Available Monitoring of Puccinia graminis subsp. graminicola and Puccinia coronata f. sp. lolii was carried out in Plant breeding station called Větrov. The pathogens were estimated on turf grass (Lolium perenne L., Deschampsia caespitosa (L. P. B. from 2009 to 2014. Puccinia graminis subsp. graminicola was detected in the increased level in 2009 and 2012. The highest amount of mixed infections was determined in 2014 because of the warmest winter from all monitored years and low precipitations. Significant differences were found out in the resistance of similar plant materials grown in different fields. Significant effect of weather conditions and supposed effect of different infectious pressure on various fields were reflected in these facts. At evaluated grasses, the highest (P < 0.05 occurence of Puccinia graminis subsp. graminicola. Lolium perenne L. was observed and the infection of Puccinia graminis subsp. graminicola (P < 0.05 was determined higher than in Deschampsia caespitosa (L. P. B.

  14. Improvement of phytoremediation of an aged petroleum hydrocarbon-contaminated soil by Rhodococcus erythropolis CD 106 strain.

    Science.gov (United States)

    Płociniczak, Tomasz; Fic, Ewa; Pacwa-Płociniczak, Magdalena; Pawlik, Małgorzata; Piotrowska-Seget, Zofia

    2017-07-03

    The aim of this study was to assess the impact of soil inoculation with the Rhodococcus erythropolis CD 106 strain on the effectiveness of the phytoremediation of an aged hydrocarbon-contaminated [approx. 1% total petroleum hydrocarbon (TPH)] soil using ryegrass (Lolium perenne). The introduction of CD 106 into the soil significantly increased the biomass of ryegrass and the removal of hydrocarbons in planted soil. The fresh weight of the shoots and roots of plants inoculated with CD 106 increased by 49% and 30%, respectively. After 210 days of the experiment, the concentration of TPH was reduced by 31.2%, whereas in the planted, non-inoculated soil, it was reduced by 16.8%. By contrast, the concentration of petroleum hydrocarbon decreased by 18.7% in non-planted soil bioaugmented with the CD 106 strain. The rifampicin-resistant CD 106 strain survived after inoculation into soil and was detected in the soil during the entire experimental period, but the number of CD 106 cells decreased constantly during the enhanced phytoremediation and bioaugmentation experiments. The plant growth-promoting and hydrocarbon-degrading properties of CD 106, which are connected with its long-term survival and limited impact on autochthonous microflora, make this strain a good candidate for improving the phytoremediation efficiency of soil contaminated with hydrocarbons.

  15. Evolution of floral meristem identity genes. Analysis of Lolium temulentum genes related to APETALA1 and LEAFY of Arabidopsis

    DEFF Research Database (Denmark)

    Gocal, G.F.W.; King, R.W.; Blundell, C.A.

    2001-01-01

    Flowering (inflorescence formation) of the grass Lolium temulentum is strictly regulated, occurring rapidly on exposure to a single long day (LD). During floral induction, L. temulentum differs significantly from dicot species such as Arabidopsis in the expression, at the shoot apex, of two APETALA...... are consecutively activated early during flower formation. LtMADS2, when expressed in transgenic Arabidopsis plants under the control of the AP1 promoter, could partially complement the organ number defect of the severe ap1-15 mutant allele, confirming a close relationship between LtMADS2 and AP1....

  16. ‘‘Blind'' mapping of genic DNA sequence polymorphisms in Lolium perenne L. by high resolution melting curve analysis

    DEFF Research Database (Denmark)

    Studer, Bruno; Jensen, Louise Bach; Fiil, Alice

    2009-01-01

    High resolution melting curve analysis (HRM) measures dissociation of double stranded DNA of a PCR product amplified in the presence of a saturating fluorescence dye. Recently, HRM proved successful to genotype DNA sequence polymorphisms such as SSRs and SNPs based on the shape of the melting...... curves. In this study, HRM was used for simultaneous screening and genotyping of genic DNA sequence polymorphisms identified in the Lolium perenne F2 mapping population VrnA. Melting profiles of PCR products amplified from previously published gene loci and from a novel gene putatively involved...

  17. VALOR ALIMENTAR DE DIETAS COM AZEVÉM (Lolium multiflorum, LAM.) E SUPLEMENTAÇÃO NITROGENADA OU ENERGÉTICA

    OpenAIRE

    Glaucia Azevedo do Amaral

    2008-01-01

    Este estudo foi conduzido com o objetivo de avaliar se e em que grau a oferta suplementar de amido ou proteína degradável no rúmen, assim como de proteína não degradável, afetam o consumo, os processos de digestão, a retenção de nitrogênio, a digestibilidade ruminal e o fluxo duodenal das frações nitrogenadas em ovinos alimentados com azevém (Lolium multiflorum, Lam) à vontade. Foram utilizados dez cordeiros castrados Corriedale (PV médio de 26 kg), mantidos em gaiolas de metabolismo em...

  18. Short-term effects of a dung pat on N2 fixation and total N uptake in a perennial ryegrass/white clover mixture

    DEFF Research Database (Denmark)

    Jørgensen, F.V.; Jensen, E.S.

    1997-01-01

    The short-term effects of a simulated cattle dung pat on N-2 fixation and total uptake of N in a perennial ryegrass/white clover mixture was studied in a container experiment using sheep faeces mixed with water to a DM content of 13%. We used a new N-15 cross-labelling technique to determine...

  19. Removal of nutrients and veterinary antibiotics from swine wastewater by a constructed macrophyte floating bed system.

    Science.gov (United States)

    Xian, Qiming; Hu, Lixia; Chen, Hancheng; Chang, Zhizhou; Zou, Huixian

    2010-12-01

    The potential of three varieties of Italian ryegrass (Lolium multiflorum Lam.), Dryan, Tachimasari and Waseyutaka, to improve the water quality of swine wastewater was evaluated using a constructed macrophyte floating bed system. With respect to reductions in levels of nutrients, chemical oxygen demand (COD), and sulfonamide antimicrobials (SAs, including sulfadiazine, sulfamethazine, and sulfamethoxazole), Dryan performed better than Tachimasari and Waseyutaka. For Dryan, total N was reduced by 84.0%, total P by 90.4%, COD by 83.4% and sulfonamide antimicrobials by 91.8-99.5%. Similar results were observed for Tachimasari and Waseyutaka. The results indicated that the treatment of swine wastewater using the constructed macrophyte floating bed system was effective in the removal of nutrients and veterinary antibiotics. Copyright © 2010 Elsevier Ltd. All rights reserved.

  20. An investigation into the potential use and sustainability of surfactant coated turfgrass seed for the green industry

    Science.gov (United States)

    Fidanza, Michael; McMillan, Mica; Kostka, Stan; Madsen, Matthew D.

    2014-05-01

    Turfgrass seed germination and emergence is influenced mostly by water and oxygen availability, temperature, nutrition and biological activity in the rootzone. In many areas globally, seed germination and subsequent turfgrass establishment is greatly diminished due to inadequate irrigation water amount and quality, and the problem is further compound due to water repellent soils. Successful turfgrass seed germination is critical when attempting to establish a more sustainable turfgrass species in place of an existing, high-input required turf stand. Greenhouse research investigations were conducted in 2013 in Pennsylvania (USA), to evaluate surfactant coated perennial ryegrass (Lolium perenne) and Kentucky bluegrass (Poa pratensis) seed for germination and emergence, seedling vigor and overall turfgrass quality. Both turfgrasses tested are cool-season or C3 grasses, and perennial ryegrass has a bunch-type growth habit while Kentucky bluegrass is rhizomatous. Perennial ryegrass is used world-wide as a principal component in sports turf mixes and in overseeding programs, and typically germinates rapidly in 3 to 10 days after seeding. Kentucky bluegrass also is used world-wide for sports turf as well as lawns and landscapes, and germinates slowly in 7 to 28 days. Research results indicate that surfactant coated seed of both species germinated one to three days faster compared to uncoated seed, and that seedling vigor and overall turfgrass quality was better with surfactant coated seed compared to uncoated seed. In a study with only perennial ryegrass, surfactant-coated seed without fertilizer (i.e., N and Ca) applied at time of sowing resulted in seedling vigor and quality considered to be similar or better than uncoated seed with fertilizer applied at time of sowing. Therefore, the potential benefits with seed germination and emergence, and seedling vigor and turfgrass quality also may be attributed to the surfactant coating and not only a fertilizer response. The

  1. Comportamento de vacas em lactação em pastagem manejada sob princípios agroecológicos Behavior of grazing lactating cows in agro-ecological managed pastures

    Directory of Open Access Journals (Sweden)

    Clair Jorge Olivo

    2006-12-01

    Full Text Available Este estudo foi realizado com o objetivo de estudar o comportamento de vacas holandesas em lactação durante o período hibernal em pastagem constituída de capim-elefante (Pennisetum purpureum Schum., aveia preta (Avena strigosa Schreb. e azevém (Lolium multiflorum Lam.. As avaliações foram feitas em três ciclos de pastejo, em 17/06, 04/08 e 16/09 de 2004. Em cada avaliação, utilizaram-se seis vacas entre o 2º e o 5º mês de lactação. O registro de dados foi realizado por dois observadores das 18 às 6h e das 8 às 16h, a cada 10 minutos. As características comportamentais observadas foram os tempos de pastejo em capim-elefante e em aveia + azevém, em pastejo total (pastejo de capim-elefante + aveia e azevém, em ruminação e ócio. Concomitantemente, avaliaram-se os dados da massa de forragem inicial, da qualidade da forragem ingerida e das condições ambientais. A maior intensidade de pastejo ocorreu após cada ordenha, verificando-se posteriormente um decréscimo, tanto durante o dia quanto à noite. Em média, o turno que os animais demandaram mais tempo de pastejo foi o diurno. O tempo destinado pelas vacas ao consumo de aveia e de azevém foi maior no período em que o capim-elefante apresentava menor porcentagem de lâminas foliares. O tempo de ócio diminuiu e o de ruminação aumentou no decorrer dos pastejos, como resultado do declínio na porcentagem de lâminas foliares e da elevação na porcentagem de colmos das espécies de ciclo hibernal. O capim-elefante foi pastejado em todas as avaliações. A presença de espécies de ciclos diferentes possibilitou aos animais equilibrarem a dieta volumosa.The objective of this trial was to study the behavior of lactating Holstein cows grazing pasture containing elephantgrass (Pennisetum purpureum Schum. and a mixture of black oat (Avena strigosa Schreb. plus ryegrass (Lolium multiflorum Lam.. Data from six early to mid lactating cows were collected every 10 minutes interval

  2. Effect of biochar on the presence of nutrients and ryegrass growth in the soil from an abandoned indigenous coking site: The potential role of biochar in the revegetation of contaminated site.

    Science.gov (United States)

    Zhang, Guixiang; Guo, Xiaofang; Zhu, Yuen; Han, Zhiwang; He, Qiusheng; Zhang, Fengsong

    2017-12-01

    Little is known regarding how biochars' feedstock and pyrolysis temperature affect soil function and plant growth. To address this gap in knowledge, 12 biochars (walnut shells, corn cobs, corn straws, and rice straws were separately pyrolyzed at 250, 400, and 600°C for 4h) were applied to soil from an indigenous coking site with application rate of 2.5% (w/w) in a pot experiment to determine the impact of biochar types on macro-nutrients (total and available N, P, and K) and ryegrass growth in the soil from an indigenous coking site. Generally, the total N, P, and K in the soil was not significantly different from that of the control group. However, biochars decreased the available N from 21.76mg·kg -1 for the control to 14.96mg·kg -1 . Corn straw and rice straw biochars increased the available P from 2.14mg·kg -1 for the control to 28.35mg·kg -1 , specifically at higher pyrolysis temperature, while walnut shell and corn cob biochars had little influence on it regardless of pyrolysis temperature. Biochars increased the available K from 173.58mg·kg -1 for the control to 355.64mg·kg -1 , varying as their feedstocks of corn cob>rice straw>corn straw>walnut shell and increasing with the increase of pyrolysis temperature. Correlation analysis suggests that it is responsible for the competition of soluble cations from biochars with K for adsorption sites on the soil surface. Biochars increased the ryegrass biomass from 0.07g·pot -1 for the control to 0.16g·pot -1 , with the generally most effective stimulation by biochars produced at 400°C. Ryegrass biomass had obviously positive correlation with available K, indicating its essential role in the growth of ryegrass in the studied soil. Copyright © 2017. Published by Elsevier B.V.

  3. Desempenho de forrageiras em sistemas alagados de tratamento de águas residuárias do processamento do café Performance of forage crops in wetlands used in the treatment of wastewater of coffee processing

    Directory of Open Access Journals (Sweden)

    Ronaldo Fia

    2010-01-01

    Full Text Available Duas gramíneas forrageiras de inverno, azevém (Lolium multiflorum e aveia preta (Avena strigosa Schreb, foram cultivadas em sistemas alagados construídos (SACs utilizados no tratamento das águas residuárias do processamento dos frutos do cafeeiro (ARC com o objetivo de se avaliar seu desempenho agronômico. Essas forrageiras foram submetidas a diferentes cargas orgânicas (650 a 1.500 kg ha-1 d-1 de DQO, proporcionadas pela aplicação dos efluentes de filtros anaeróbios, utilizados no tratamento da ARC. Como tratamento testemunha, as mesmas espécies vegetais foram cultivadas em solução de Hoagland. A matéria seca produzida pelas forrageiras ao longo dos 53 dias de monitoramento dos SACs variou de 7,4 a 14,0 e 0,5 a 2,7 t ha-1, e os rendimentos acumulados de proteína bruta variaram de 1.017 a 2.187 e 66,6 a 316,8 kg ha-1 para o azevém e a aveia, respectivamente. Os resultados permitiram concluir que, dentre as forrageiras estudadas, o azevém se mostrou mais adequado para ser cultivado em SACs utilizados no pós-tratamento da ARC efluente de filtros anaeróbios, já que apresentou maior rendimento de matéria seca e proteína bruta e, portanto, melhor adaptação ao sistema.Two winter grasses, ryegrass (Lolium multiflorum and oats (Avena strigosa Schreb, were grown in constructed wetlands (SACs used in the treatment of wastewater of coffee processing (ARC with the aim to evaluate their agronomic performance. These forage crops were submitted to different organic loads (650 to 1500 kg ha-1 d-1 of COD, offered by the application of anaerobic effluent filters, used in the treatment of ARC. As a control treatment, the same plant species were grown in a Hoagland solution. The forage dry matter produced by over 53 days of monitoring SACs ranged from 7.4 to 14.0 and from 0.5 to 2.7 t ha-1, and the crude protein yield ranged from 1017 to 2187 and 66.6 to 316.8 kg ha-1 for ryegrass and oats, respectively. The results showed that, among the

  4. Evolutionary history of tall fescue morphotypes inferred from molecular phylogenetics of the Lolium-Festuca species complex

    Directory of Open Access Journals (Sweden)

    Stewart Alan V

    2010-10-01

    Full Text Available Abstract Background The agriculturally important pasture grass tall fescue (Festuca arundinacea Schreb. syn. Lolium arundinaceum (Schreb. Darbysh. is an outbreeding allohexaploid, that may be more accurately described as a species complex consisting of three major (Continental, Mediterranean and rhizomatous morphotypes. Observation of hybrid infertility in some crossing combinations between morphotypes suggests the possibility of independent origins from different diploid progenitors. This study aims to clarify the evolutionary relationships between each tall fescue morphotype through phylogenetic analysis using two low-copy nuclear genes (encoding plastid acetyl-CoA carboxylase [Acc1] and centroradialis [CEN], the nuclear ribosomal DNA internal transcribed spacer (rDNA ITS and the chloroplast DNA (cpDNA genome-located matK gene. Other taxa within the closely related Lolium-Festuca species complex were also included in the study, to increase understanding of evolutionary processes in a taxonomic group characterised by multiple inter-specific hybridisation events. Results Putative homoeologous sequences from both nuclear genes were obtained from each polyploid species and compared to counterparts from 15 diploid taxa. Phylogenetic reconstruction confirmed F. pratensis and F. arundinacea var. glaucescens as probable progenitors to Continental tall fescue, and these species are also likely to be ancestral to the rhizomatous morphotype. However, these two morphotypes are sufficiently distinct to be located in separate clades based on the ITS-derived data set. All four of the generated data sets suggest independent evolution of the Mediterranean and Continental morphotypes, with minimal affinity between cognate sequence haplotypes. No obvious candidate progenitor species for Mediterranean tall fescues were identified, and only two putative sub-genome-specific haplotypes were identified for this morphotype. Conclusions This study describes the first

  5. Mechanism of Resistance to Glyphosate in Lolium perenne from Argentina

    Directory of Open Access Journals (Sweden)

    Marcos Yanniccari

    2017-10-01

    Full Text Available In Argentina, glyphosate resistance was reported in a Lolium perenne population after 12 years of successful herbicide use. The aim of the current paper was to put in evidence for the mechanism of glyphosate resistance of this weed. Susceptible leaves treated with different doses of glyphosate and incubated in vitro showed an accumulation of shikimic acid of around three to five times the basal level, while no changes were detected in leaves of glyphosate-resistant plants. The resistance mechanism prevents shikimate accumulation in leaves, even under such tissue-isolation conditions. The activity of the glyphosate target enzyme (EPSPS: 5-enolpyruvylshikimate-3-phosphate synthase was quantified at different herbicide concentrations. EPSPS from resistant plants showed no difference in glyphosate-sensitivity compared to EPSPS from susceptible plants, and, accordingly, no amino acid substitution causing mutations associated with resistance were found. While the glyphosate target enzymes were equally sensitive, the basal EPSPS activity in glyphosate resistant plants was approximately 3-fold higher than the EPSPS activity in susceptible plants. This increased EPSPS activity in glyphosate resistant plants was associated with a 15-fold higher expression of EPSPS compared with susceptible plants. Therefore, the over-expression of EPSPS appears to be the main mechanism responsible for resistance to glyphosate. This mechanism has a constitutive character and has important effects on plant fitness, as recently reported.

  6. EFECTO DEL PICADO SOBRE LAS CARACTERÍSTICAS NUTRICIONALES Y FERMENTATIVAS DE ENSILAJES DE PASTOS KIKUYO, RYEGRASS PERENNE Y ALPISTE FORRAJERO

    Directory of Open Access Journals (Sweden)

    Luis Villalobos

    2016-01-01

    Full Text Available Se evaluó el efecto del picado sobre las características nutricionales y fermentativas de ensilajes elaborados con 3 pastos (kikuyo, rye-grass perenne y alpiste forrajero. Se elaboraron 2 microsilos de cada pasto en bolsas de polieti-leno con capacidad para 1 kg, aplicando 2 trata-mientos (picado y sin picar; se adicionó a cada microsilo 3% de melaza y 0,1% de un inóculo artesanal (hecho de leche agria, suero de queso y melaza. La especie de pasto tuvo el mayor impacto sobre las características nutricionales y fermentativas de los microsilos, mientras que el picado no mostró tendencia clara sobre los parámetros evaluados. El contenido de PC (14,40 a 19,35%, FDN (46,25 a 63,16% y la DIVMS (46,15 a 65,55% en los ensilados es indicador de su potencial para llenar gran parte de los requerimientos nutricionales del ganado lechero. El pasto ryegrass ensilado alcanzó los niveles de pH (4,41 a 4,83 menores y el pasto kikuyo los valores menores de capacidad amor-tiguadora (79,12 a 81,17 mEq NaOH 100 g-1 MS y de nitrógeno amoniacal (1,03 a 1,33%. Los ensilajes elaborados con pastos pueden uti-lizarse como suplementos con valor nutricional superior a los henos utilizados en las raciones de ganado lechero en zonas altas.

  7. Phorate can reverse P450 metabolism-based herbicide resistance in Lolium rigidum.

    Science.gov (United States)

    Busi, Roberto; Gaines, Todd Adam; Powles, Stephen

    2017-02-01

    Organophosphate insecticides can inhibit specific cytochrome P450 enzymes involved in metabolic herbicide resistance mechanisms, leading to synergistic interactions between the insecticide and the herbicide. In this study we report synergistic versus antagonistic interactions between the organophosphate insecticide phorate and five different herbicides observed in a population of multiple herbicide-resistant Lolium rigidum. Phorate synergised with three different herbicide modes of action, enhancing the activity of the ALS inhibitor chlorsulfuron (60% LD 50 reduction), the VLCFAE inhibitor pyroxasulfone (45% LD 50 reduction) and the mitosis inhibitor trifluralin (70% LD 50 reduction). Conversely, phorate antagonised the two thiocarbamate herbicides prosulfocarb and triallate with a 12-fold LD 50 increase. We report the selective reversal of P450-mediated metabolic multiple resistance to chlorsulfuron and trifluralin in the grass weed L. rigidum by synergistic interaction with the insecticide phorate, and discuss the putative mechanistic basis. This research should encourage diversity in herbicide use patterns for weed control as part of a long-term integrated management effort to reduce the risk of selection of metabolism-based multiple herbicide resistance in L. rigidum. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  8. Colonization on root surface by a phenanthrene-degrading endophytic bacterium and its application for reducing plant phenanthrene contamination.

    Directory of Open Access Journals (Sweden)

    Juan Liu

    Full Text Available A phenanthrene-degrading endophytic bacterium, Pn2, was isolated from Alopecurus aequalis Sobol grown in soils contaminated with polycyclic aromatic hydrocarbons (PAHs. Based on morphology, physiological characteristics and the 16S rRNA gene sequence, it was identified as Massilia sp. Strain Pn2 could degrade more than 95% of the phenanthrene (150 mg · L(-1 in a minimal salts medium (MSM within 48 hours at an initial pH of 7.0 and a temperature of 30 °C. Pn2 could grow well on the MSM plates with a series of other PAHs, including naphthalene, acenaphthene, anthracene and pyrene, and degrade them to different degrees. Pn2 could also colonize the root surface of ryegrass (Lolium multiflorum Lam, invade its internal root tissues and translocate into the plant shoot. When treated with the endophyte Pn2 under hydroponic growth conditions with 2 mg · L(-1 of phenanthrene in the Hoagland solution, the phenanthrene concentrations in ryegrass roots and shoots were reduced by 54% and 57%, respectively, compared with the endophyte-free treatment. Strain Pn2 could be a novel and useful bacterial resource for eliminating plant PAH contamination in polluted environments by degrading the PAHs inside plants. Furthermore, we provide new perspectives on the control of the plant uptake of PAHs via endophytic bacteria.

  9. Zea mI, the maize homolog of the allergen-encoding Lol pI gene of rye grass.

    Science.gov (United States)

    Broadwater, A H; Rubinstein, A L; Chay, C H; Klapper, D G; Bedinger, P A

    1993-09-15

    Sequence analysis of a pollen-specific cDNA from maize has identified a homolog (Zea mI) of the gene (Lol pI) encoding the major allergen of rye-grass pollen. The protein encoded by the partial cDNA sequence is 59.3% identical and 72.7% similar to the comparable region of the reported amino acid sequence of Lol pIA. Southern analysis indicates that this cDNA represents a member of a small multigene family in maize. Northern analysis shows expression only in pollen, not in vegetative or female floral tissues. The timing of expression is developmentally regulated, occurring at a low level prior to the first pollen mitosis and at a high level after this postmeiotic division. Western analysis detects a protein in maize pollen lysates using polyclonal antiserum and monoclonal antibodies directed against purified Lolium perenne allergen.

  10. Marker-assisted selection for improving quantitative traits of forage crops

    International Nuclear Information System (INIS)

    Dolstra, O.; Denneboom, C.; Vos, Ab L.F. de; Loo, E.N. van

    2007-01-01

    This chapter provides an example of using marker-assisted selection (MAS) for breeding perennial ryegrass (Lolium perenne), a pasture species. A mapping study had shown the presence of quantitative trait loci (QTL) for seven component traits of nitrogen use efficiency (NUE). The NUE-related QTL clustered in five chromosomal regions. These QTL were validated through divergent marker selection in an F 2 population. The criterion used for plant selection was a summation index based on the number of positive QTL alleles. The evaluation studies showed a strong indirect response of marker selection on NUE. Marker selection using a summation index such as applied here proved to be very effective for difficult and complex quantitative traits such as NUE. The strategy is easily applicable in outbreeding crops to raise the frequency of several desirable alleles simultaneously. (author)

  11. The transfer of radionuclides from contaminated groundwater into perennial ryegrass and winter wheat

    International Nuclear Information System (INIS)

    Wadey, P.; Shaw, G.; Butler, A. P.; Tompkins, J. A.; Wheater, H. S.

    1996-01-01

    Lysimeter studies of the migration of radionuclides from a contaminated water table and their subsequent uptake by plant roots have been undertaken using two distinct soil types and varying crop regimes. An eight year multi-disciplinary research project (funded by Nirex) has concentrated on the upward migration of contaminants from near-surface water tables, and their uptake by winter wheat and perennial ryegrass crops. Experimental data are presented for the movement and uptake of radiocaesium 137 Cs. These data show significant movement in the unsaturated zone during the first year of dosing, followed by progressively reduced availability in subsequent years. A suite of physically based hydrological and solute transport models has been developed to model radionuclide transport in the unsaturated zone. Model simulations, based on a conventional advection-dispersion representation incorporating linear sorption processes, were unable to describe adequately the distribution of radiocaesium within the soil profile. However, the introduction of root storage and translocation processes provided significantly improved results. (author)

  12. Molecular characterization of cytoplasmic male sterility (CMS) in perennial ryegrass ( Lolium perenne L.)

    DEFF Research Database (Denmark)

    Islam, Md. Shofiqul; Møller, Ian Max; Studer, Bruno

    2011-01-01

    to increase biomass yield, improve nutritional value and tolerance towards abiotic and biotic stress. Cytoplasmic male sterility (CMS) is an efficient tool to control pollination for hybrid seed production. In order to identify the causative polymorphism of the CMS phenotype, a cytoplasmic male sterile plant...

  13. Foliar or root exposures to smelter particles: Consequences for lead compartmentalization and speciation in plant leaves

    International Nuclear Information System (INIS)

    Schreck, Eva; Dappe, Vincent; Sarret, Géraldine; Sobanska, Sophie; Nowak, Dorota; Nowak, Jakub; Stefaniak, Elżbieta Anna; Magnin, Valérie; Ranieri, Vincent; Dumat, Camille

    2014-01-01

    In urban areas with high fallout of airborne particles, metal uptake by plants mainly occurs by foliar pathways and can strongly impact crop quality. However, there is a lack of knowledge on metal localization and speciation in plants after pollution exposure, especially in the case of foliar uptake. In this study, two contrasting crops, lettuce (Lactuca sativa L.) and rye-grass (Lolium perenne L.), were exposed to Pb-rich particles emitted by a Pb-recycling factory via either atmospheric or soil application. Pb accumulation in plant leaves was observed for both ways of exposure. The mechanisms involved in Pb uptake were investigated using a combination of microscopic and spectroscopic techniques (electron microscopy, laser ablation, Raman microspectroscopy, and X-ray absorption spectroscopy). The results show that Pb localization and speciation are strongly influenced by the type of exposure (root or shoot pathway) and the plant species. Foliar exposure is the main pathway of uptake, involving the highest concentrations in plant tissues. Under atmospheric fallouts, Pb-rich particles were strongly adsorbed on the leaf surface of both plant species. In lettuce, stomata contained Pb-rich particles in their apertures, with some deformations of guard cells. In addition to PbO and PbSO 4 , chemical forms that were also observed in pristine particles, new species were identified: organic compounds (minimum 20%) and hexagonal platy crystals of PbCO 3 . In rye-grass, the changes in Pb speciation were even more egregious: Pb–cell wall and Pb–organic acid complexes were the major species observed. For root exposure, identified here as a minor pathway of Pb transfer compared to foliar uptake, another secondary species, pyromorphite, was identified in rye-grass leaves. Finally, combining bulk and spatially resolved spectroscopic techniques permitted both the overall speciation and the minor but possibly highly reactive lead species to be determined in order to better

  14. Foliar or root exposures to smelter particles: Consequences for lead compartmentalization and speciation in plant leaves

    Energy Technology Data Exchange (ETDEWEB)

    Schreck, Eva [Université de Toulouse, INP, UPS, EcoLab (Laboratoire Ecologie Fonctionnelle et Environnement), ENSAT, Avenue de l' Agrobiopole, 31326 Castanet-Tolosan (France); CNRS, EcoLab, 31326 Castanet-Tolosan (France); Géosciences Environnement Toulouse (GET), Observatoire Midi Pyrénées, Université de Toulouse, CNRS, IRD, 14 Avenue E. Belin, F-31400 Toulouse (France); Dappe, Vincent [LASIR (UMR CNRS 8516), Université de Lille 1, Bât. C5, 59655 Villeneuve d' Ascq Cedex (France); Sarret, Géraldine [ISTerre, UMR 5275, Université Grenoble I, CNRS, F-38041 Grenoble (France); Sobanska, Sophie [LASIR (UMR CNRS 8516), Université de Lille 1, Bât. C5, 59655 Villeneuve d' Ascq Cedex (France); Nowak, Dorota; Nowak, Jakub; Stefaniak, Elżbieta Anna [Department of Chemistry, John Paul II Catholic University of Lublin, Al. Kraśnicka 102, 20-718 Lublin (Poland); Magnin, Valérie [ISTerre, UMR 5275, Université Grenoble I, CNRS, F-38041 Grenoble (France); Ranieri, Vincent [CEA-INAC, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France); Dumat, Camille, E-mail: camille.dumat@ensat.fr [Université de Toulouse, INP, UPS, EcoLab (Laboratoire Ecologie Fonctionnelle et Environnement), ENSAT, Avenue de l' Agrobiopole, 31326 Castanet-Tolosan (France); CNRS, EcoLab, 31326 Castanet-Tolosan (France)

    2014-04-01

    In urban areas with high fallout of airborne particles, metal uptake by plants mainly occurs by foliar pathways and can strongly impact crop quality. However, there is a lack of knowledge on metal localization and speciation in plants after pollution exposure, especially in the case of foliar uptake. In this study, two contrasting crops, lettuce (Lactuca sativa L.) and rye-grass (Lolium perenne L.), were exposed to Pb-rich particles emitted by a Pb-recycling factory via either atmospheric or soil application. Pb accumulation in plant leaves was observed for both ways of exposure. The mechanisms involved in Pb uptake were investigated using a combination of microscopic and spectroscopic techniques (electron microscopy, laser ablation, Raman microspectroscopy, and X-ray absorption spectroscopy). The results show that Pb localization and speciation are strongly influenced by the type of exposure (root or shoot pathway) and the plant species. Foliar exposure is the main pathway of uptake, involving the highest concentrations in plant tissues. Under atmospheric fallouts, Pb-rich particles were strongly adsorbed on the leaf surface of both plant species. In lettuce, stomata contained Pb-rich particles in their apertures, with some deformations of guard cells. In addition to PbO and PbSO{sub 4}, chemical forms that were also observed in pristine particles, new species were identified: organic compounds (minimum 20%) and hexagonal platy crystals of PbCO{sub 3}. In rye-grass, the changes in Pb speciation were even more egregious: Pb–cell wall and Pb–organic acid complexes were the major species observed. For root exposure, identified here as a minor pathway of Pb transfer compared to foliar uptake, another secondary species, pyromorphite, was identified in rye-grass leaves. Finally, combining bulk and spatially resolved spectroscopic techniques permitted both the overall speciation and the minor but possibly highly reactive lead species to be determined in order to

  15. THE EFFECT OF COMPOST MADE WITH SEWAGE SLUDGE ON HEAVY METAL CONTENT IN SOIL AND IN LOLIUM MULTIFLORUM LAM.

    Directory of Open Access Journals (Sweden)

    Elżbieta Malinowska

    2016-07-01

    Full Text Available The aim of this paper is to assess the effects of different doses of sewage sludge compost mixed with wheat straw on heavy metal content in Italian ryegrass and in soil. A two year experiment with the Italian ryegrass was set up in autumn 2012. The experimental design consisted of a control plot, a plot with NPK fertiliser and three plots with three different doses of municipal sewage sludge compost (5, 10 and 15 Mg of fresh matter·ha-1. Those different compost doses contained the amounts of Nitrogen equivalent to 60, 120 and 180 kg N·ha-1. The two lower doses of compost were supplemented with nitrogen fertiliser so that the amount of this chemical element introduced to the soil of all plots with compost stood at 180 kg·ha-1. During 2013 and 2014 seasons the grass was cut three times a year after about a 30-day growing period. After dry mineralisation the content of Zn, Cu, Ni, Pb and Cd in the plant samples was measured with the ICP-AES method. The fertilisers applied significantly diversified the content of chemical elements in the grass and in the soil. The highest dose of compost resulted in the highest concentration of Zn, Cu and Cd in the grass while the highest concentration of Ni and Pb was in the soil and the grass from the plot where the mid dose of compost had been applied. Cadmium concentration in the soil was the highest in the plot where the mid dose was applied. The experiment proved that compost made with sewage sludge and wheat straw is beneficial for plants.

  16. Genomic Selection Using Genotyping-By-Sequencing Data with Different Coverage Depth in Perennial Ryegrass

    DEFF Research Database (Denmark)

    Cericola, Fabio; Fé, Dario; Janss, Luc

    2015-01-01

    the diagonal elements by estimating the amount of genetic variance caused by the reduction of the coverage depth. Secondly we developed a method to scale the relationship matrix by taking into account the overall amount of pairwise non-missing loci between all families. Rust resistance and heading date were......Genotyping by sequencing (GBS) allows generating up to millions of molecular markers with a cost per sample which is proportional to the level of multiplexing. Increasing the sample multiplexing decreases the genotyping price but also reduces the numbers of reads per marker. In this work we...... investigated how this reduction of the coverage depth affects the genomic relationship matrices used to estimated breeding value of F2 family pools in perennial ryegrass. A total of 995 families were genotyped via GBS providing more than 1.8M allele frequency estimates for each family with an average coverage...

  17. Determination of Cardinal Temperatures for Cool Season Turfgrass and Two Common Weed Species

    Directory of Open Access Journals (Sweden)

    Marjan Diayanat

    2018-02-01

    Full Text Available Introduction The presence of broadleaf weeds not only reduces the aesthetic quality of the turfgrass, but more importantly they compete with desired turfgrass for water, nutrients, and light. Weed management after seeding is an important component to successfully establishing a healthy stand of cool season turfgrass. Weed seed germination is a key process because determines both the number of weeds that could potentially emerge and the timing of their appearance in the turfgrass. Temperature is of the most important factor regulating germination of non-dormant seeds in irrigated, annual agroecosystems at the beginning of the growth season where light, nutrients, and moisture are typically not growth limiting. Also prostrate knotweed (Polygonum aviculare L. and annual sowthistle (Sonchus oleraceus L. are two annual common broad leaf weeds in cool season turfgrass. Prostrate knotweed is very competitive in infertile and compacted soils and often invades turfgrasses along driveways, sidewalks, and beaten paths across lawns. Annual sowthistle is found in open habitats that include waste areas, turf, and roadsides. The aim of this study was to evaluate different nonlinear regression models to describe response of germination rate to different temperatures in perennial ryegrass (Lolium perenne L., fescue (Festuca rubra L., prostrate knotweed and annual sowthistle. Materials and Methods This experiment was based on completely randomized design with 4 replications at Islamic Azad University in the laboratory of Science Research Branch in 2015. The seeds were treated with different temperatures (2, 5, 10, 15, 20, 25, 30, 35, 40 and 45oC Twenty five seeds were placed in each petri dish for each species in per replication. Ten milliliters of distilled water were added to each petri dish and the filter papers were regularly moistened to ensure saturation throughout the germination tests. Petri dishes were placed in germinator with 16 hour day, 8 hour night

  18. Carbon turnover in two soils with contrasting mineralogy under long-term maize and pasture

    International Nuclear Information System (INIS)

    Parfitt, R.L.; Parshotam, A.; Salt, G.J.

    2002-01-01

    Total organic carbon (C) and natural 13 C abundance were measured in adjacent allophanic soils (Andisols) and non-allophanic soils (Inceptisols) under maize (Zea mays L.) and ryegrass pasture (Lolium perenne L.) to assess the C turnover rate in soils of contrasting mineralogy and specific surface area. The allophanic soil contained more total C than the non-allophanic soil (139v.101t C/ha in the upper 0-35 cm) but neither soil showed a significant difference in C content between pasture and maize, provided maize residue was retained and incorporated. The gross annual inputs under maize and pasture were both estimated to be about 9 t C/ha, consistent with the similar soil total C contents. Since the soil total C content did not appear to change with time, the gross C mineralisation was about 9 t C/ha each year. The proportion of old pasture C remaining in the soil after maize cropping for 25 years was about 78% in the allophanic soils and about 69% in the non-allophanic soils, reflecting the influence of both Al and allophane, with its high specific surface area, on the retention of old C. The maize C retained in 25 years was similar in both the allophanic soil and the non-allophanic soil (29 t/ha). Therefore, the higher total C content of the allophanic soil would appear to arise from stabilisation of old pasture and forest C by Al and allophane. Copyright (2002) CSIRO Publishing

  19. Soil physical properties and grape yield influenced by cover crops and management systems

    Directory of Open Access Journals (Sweden)

    Jaqueline Dalla Rosa

    2013-10-01

    Full Text Available The use of cover crops in vineyards is a conservation practice with the purpose of reducing soil erosion and improving the soil physical quality. The objective of this study was to evaluate cover crop species and management systems on soil physical properties and grape yield. The experiment was carried out in Bento Gonçalves, RS, Southern Brazil, on a Haplic Cambisol, in a vineyard established in 1989, using White and Rose Niagara grape (Vitis labrusca L. in a horizontal, overhead trellis system. The treatments were established in 2002, consisting of three cover crops: spontaneous species (SS, black oat (Avena strigosa Schreb (BO, and a mixture of white clover (Trifolium repens L., red clover (Trifolium pratense L. and annual rye-grass (Lolium multiflorum L. (MC. Two management systems were applied: desiccation with herbicide (D and mechanical mowing (M. Soil under a native forest (NF area was collected as a reference. The experimental design consisted of completely randomized blocks, with three replications. The soil physical properties in the vine rows were not influenced by cover crops and were similar to the native forest, with good quality of the soil structure. In the inter-rows, however, there was a reduction in biopores, macroporosity, total porosity and an increase in soil density, related to the compaction of the surface soil layer. The M system increased soil aggregate stability compared to the D system. The treatments affected grapevine yield only in years with excess or irregular rainfall.

  20. Manejo da palha de azevém, da adubação de base e da água de drenagem na produção de arroz irrigado Management of ryegrass straw, fertilizer and drainage water, on flooded rice prodution

    Directory of Open Access Journals (Sweden)

    Alexandre Swarowsky

    2004-04-01

    Full Text Available Sistemas com mínimo revolvimento do solo são favoráveis ao controle de plantas daninhas, à utilização mais intensiva dos solos de várzea e à rentabilidade do orizicultor, mas apresentam algumas limitações, como a produção de substâncias que podem ser tóxicas ao arroz, bem como alterações na disponibilidade de nutrientes em ambientes alagados. O trabalho teve como objetivo comparar diferentes sistemas de manejo da palha de azevém, da adubação de base, e da drenagem, no rendimento de grãos de arroz e nos componentes da produção. O experimento foi conduzido na Universidade Federal de Santa Maria. Foram avaliados três níveis de manejo da resteva de azevém (planta de azevém em pé, planta de azevém incorporada e sem a planta de azevém, três condições de adubação (sem adubação, adubação do arroz 100% aplicada na semeadura do azevém e adubação do arroz 100% aplicada na semeadura do arroz e dois manejos da água de drenagem (inundação convencional em condições de campo e inundação sem drenagem. Os resultados obtidos permitem concluir que, na cultura do arroz irrigado por inundação, a incorporação da palha de azevém e a aplicação da adubação para o arroz na semeadura do azevém não afetam o rendimento de grãos e os componentes da produção. Entretanto, a ausência de drenagem interna no solo reduz o rendimento de grãos de arroz, o número de panículas e o número de grãos por panícula.Cultivation systems with minimum tillage are used to minimize red rice incidence, improving crop yield and the agricultural exploration of lowland soils. However, some limitations are present such as toxic substances due to anaerobic straw decomposition (prejudicial to rice plant establishment, as well as alterations on some available nutrients under flooded soil water conditions. The objective of this work was to compare different drainage systems; ryegrass straw management and time of fertilizer application on

  1. Efficiency of Opuntia ficus in the phytoremediation of a soil contaminated with used motor oil and lead, compared to that of Lolium perenne and Aloe barbadensis.

    Science.gov (United States)

    Escobar-Alvarado, Luisa F; Vaca-Mier, Mabel; López-Callejas, Raymundo; Rojas-Valencia, Ma Neftalí

    2018-01-28

    Industrial pollutants such as heavy metals and hydrocarbons in soils represent a serious concern due to their persistence and negative effects on the environment, affecting cellular processes in living organisms and even causing mutations and cancer. The main objectives of this work were to evaluate the efficiency of Opuntia ficus in the phytoremediation of a soil polluted with used motor oil. Two other species, one with different and one with similar characteristics, relatively, were used for comparison purposes: Lolium perenne and Aloe barbadensis. The effect of the plants on lead solubility and bioaccumulation, the biomass production of each specie and the microbial counts and bacterial identification for each experiment was studied. Total petroleum hydrocarbons (TPH) were measured every 5 weeks throughout the 20-week phytoremediation experiment. At the end of the experiment soluble Pb, Pb extracted by the plant species, microbiological counts, total biomass and bacterial species in soil were analyzed. Even though Lolium perenne showed the highest TPH removal (47%), Opuntia ficus produced the highest biomass and similar removal (46%). Since Opuntia ficus requires low amounts of water and grows fast, it would be a suitable option in the remediation of soils polluted with hydrocarbons and/or heavy metals.

  2. Meat and bone meal and biosolids as slow-release phosphorus fertilizers

    Directory of Open Access Journals (Sweden)

    Anne Bøen

    2013-06-01

    Full Text Available Biosolids and meat and bone meal (MBM are commonly used as fertilizers in agriculture, often at application rates where total phosphorus (P far exceeds the annual demand. In a pot experiment, three biosolids and two types of MBM were tested at two commonly used application rates. Their contributions to P uptake in ryegrass (second and third season were compared with annual mineral P fertilization. The soil was analysed for extractable P (PAL and POlsen. Only soil amended with digested, limed biosolids provided a P uptake in ryegrass the third season comparable to annual NPK fertilization. Bone-rich MBM had considerable contributions to third season P uptake in soil with pH < 6. The product application rates did not influence P uptake significantly for any of the products. POlsen was found suitable to describe residual effects on soil P solubility, whereas the PAL-method was not applicable for MBM fertilized soils.

  3. Genomic prediction based on next generation sequencing of 1000 F2-families in Lolium perenne L

    DEFF Research Database (Denmark)

    Fé, Dario; Ashraf, Bilal; Greve-Pedersen, Morten

    2014-01-01

    and abiotic stresses. The study is performed on 995 F2 families originated from the DLF breeding program. All families were genotyped by reduced representation sequencing. A total of 1,020,065 SNPs were detected and used for genomic prediction. First analyses, used for model testing, have been carried out...... on salt stress tolerance. Ryegrass families where sown in rockwool blocks (in four replicates) in greenhouse, and allowed to establish over 60 days using standard fertilization and watering. Three consecutive treatments, with increasing salt (NaCl) concentrations, were applied. Ten days after initiation...... of each treatment, the percentage of green matter was evaluated by visual scoring and by digital imaging. Preliminary analysis using GBLUP have identified a significant amount of genetic variance (individual heritabilities ranging between 0.20 and 0.40 and family heritabilities up to about 0.15). Genomic...

  4. Inheritance of evolved clethodim resistance in Lolium rigidum populations from Australia.

    Science.gov (United States)

    Saini, Rupinder Kaur; Malone, Jenna; Gill, Gurjeet; Preston, Christopher

    2017-08-01

    In Australia, the extensive use of clethodim for the control of Lolium rigidum has resulted in the evolution of many clethodim-resistant L. rigidum populations. Five clethodim-resistant populations of L. rigidum were analysed for the inheritance of clethodim resistance. Reciprocal crosses were made between resistant (R) and susceptible (S) populations. Within crosses, dose-responses of reciprocal F 1 families of all populations except A61 were similar to each other, indicating that clethodim resistance in these populations is encoded on the nuclear genome. The level of dominance observed in the dose-response experiments ranged from partial to complete within the herbicide rate used. In the A61 population, within each cross, the response of F 1 from the maternal and paternal parent was different, indicating that resistance is inherited through the female parent. All backcross populations segregated in a different manner. Only one population, FP, fitted a single-gene model (1:1). Two populations fitted two-gene models: a 3:1 inheritance model for F4 and a 1:3 inheritance model for A91. For population E2, no clear pattern of inheritance was determined, suggesting more complex inheritance. The results of this study indicate that different patterns of clethodim resistance in L. rigidum exist. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  5. Chemical and physical soil attributes in integrated crop-livestock system under no-tillage

    Directory of Open Access Journals (Sweden)

    Hernani Alves da Silva

    Full Text Available Although integrated crop-livestock system (ICLS under no-tillage (NT is an attractive practice for intensify agricultural production, little regional information is available on the effects of animal grazing and trampling, particularly dairy heifers, on the soil chemical and physical attributes. The objective of this study was to evaluate the effects of animal grazing on the chemical and physical attributes of the soil after 21 months of ICLS under NT in a succession of annual winter pastures (2008, soybeans (2008/2009, annual winter pastures (2009, and maize (2009/10. The experiment was performed in the municipality of Castro (PR in a dystrophic Humic Rhodic Hapludox with a clay texture. The treatments included a combination of two pasture (annual ryegrass monoculture and multicropping - annual ryegrass, black oat, white clover and red clover with animal grazing during the fall-winter period with two animal weight categories (light and heavy, in a completely randomized block experimental design with 12 replications. After the maize harvest (21 months after beginning, soil samples were collected at 0-10 and 10-20 cm layers to measure soil chemical and physical attributes. The different combinations of pasture and animal weight did not alter the total organic carbon and nitrogen in the soil, but they influence the attributes of soil acidity and exchangeable cations. The monoculture pasture of ryegrass showed greater soil acidification process compared to the multicropping pasture. When using heavier animals, the multicropping pasture showed lesser increase in soil bulk density and greater macroporosity.

  6. Rendimento de forragem e valor nutritivo de gramíneas anuais de estação fria submetidas a sombreamento por Pinus elliottii e ao sol pleno Forage yield and nutritive value of cool-season annual forage grasses shaded by Pinus elliottii trees and at full-sun

    Directory of Open Access Journals (Sweden)

    Raquel Santiago Barro

    2008-10-01

    Full Text Available Avaliou-se o efeito do sombreamento provocado por duas densidades arbóreas em uma floresta de Pinus elliottii Engelm. com 10 anos de idade sobre o rendimento e o valor nutritivo da forragem de três gramíneas de ciclo hibernal. Como tratamentos, avaliou-se a combinação de dois fatores (3 x 3 em um delineamento experimental de parcelas subdivididas com três repetições, no qual as parcelas foram as condições luminosas (proporcionadas por duas densidades arbóreas: 555 e 333 árvores/ha e luz solar plena e as subparcelas as espécies forrageiras azevém-anual (Lolium multiflorum Lam.; aveia-preta (Avena strigosa Schreb.; e aveia-branca (A. sativa L. cv. Fapa 2. A semeadura foi realizada entre 25/7/2005 e 5/8/2005 e entre 26 e 27/4/2006. O rendimento de matéria seca foi estimado em avaliações durante o estádio vegetativo (aos 104 dias após a semeadura em 2006 e em pleno florescimento (aos 132 e 170 dias, em 2005 e 2006, respectivamente. O valor nutritivo da forragem foi avaliado considerando os teores médios de proteína bruta (PB e a digestibilidade in vitro da matéria orgânica (DIVMO. O sombreamento moderado reduziu em 57% o rendimento médio de forragem dos três genótipos avaliados, mas aumentou em 2,3% o teor de proteína bruta (PB e em 5,5% a digestibilidade in vitro (DIVMO quando as plantas estavam em florescimento pleno. Entre as espécies forrageiras avaliadas, a aveia-branca e a aveia-preta apresentam maior potencial para utilização em sistemas silvipastoris na Região Sul.It was evaluated the shading effect induced by two tree densities of a ten-year-old slash pine (Pinus elliottii Engelm. forest, and at full sun, on forage dry matter yield and nutritive value of three cool-season annual grasses. Treatments were a combination of two main factors: a three light conditions induced by two tree densities (333 e 555 stems/ha and at full sun; b three cool-season annual forage grasses: Italian ryegrass (Lolium multiflorum Lam

  7. The effects of different nitrogen doses on herbage and seed yields of ...

    African Journals Online (AJOL)

    The effects of different nitrogen doses on herbage and seed yields of annual ... 250, 270 and 290 kg ha-1) of and some agricultural characteristics of annual ryegrass cv. ... doses are observed to be important for all properties of herbage yield and ... It was obtained for the seed production that the highest number of tiller (626 ...

  8. The effect of temperate or tropical pasture grazing state and grain-based concentrate allocation on dairy cattle production and behavior.

    Science.gov (United States)

    Clark, C E F; Kaur, R; Millapan, L O; Golder, H M; Thomson, P C; Horadagoda, A; Islam, M R; Kerrisk, K L; Garcia, S C

    2018-06-01

    Grain-based concentrate (GBC) supplement is of high cost to dairy farmers as a feed source as opposed to grazed pasture. Milk production response to GBC is affected by the composition and nutritive value of the remainder of the diet, animal factors, and interactions between forage type and level of GBC. In grazing systems, dairy cattle encounter contrasting pasture states, primarily because the social structure of the herd affects the timing of when each animal accesses a paddock after milking as a result of a relatively consistent cow milking order. However, the effect of feed management, namely pasture state and GBC allocation, on dairy cattle production and behavior is unknown. We examined the effect of varying GBC allocation for dairy cattle grazing differing states of kikuyu grass (Pennisetum clandestinum, a tropical pasture species; experiment 1) and annual ryegrass (Lolium multiflorum L., a temperate pasture species; experiment 2) on dry matter intake, milk production and composition, and grazing behavior. For each experiment, 90 lactating dairy cattle were randomly allocated to 2 consistent (fresh-fresh and depleted-depleted) and 2 inconsistent (fresh-depleted and depleted-fresh pasture state treatments (defined as sequences of pasture state allocation for the morning and afternoon grazing events) and 3 GBC treatments [2.7, 5.4, and 8.1 kg of dry matter (DM)/cow per day], giving 12 treatment combinations for each experiment. The duration of each experiment was 14 d, with the first 7 d used as adaptation to treatment. In each experiment, 3 cattle were selected from each of the 12 pasture type × GBC treatment groups within the experimental herd to determine herbage intake and total DM digestibility using the n-alkanes method (n = 36). There was no interaction between kikuyu grass or ryegrass pasture state and GBC level for intake, digestibility, or milk yield or components. Dairy cattle offered fresh-fresh and depleted-fresh ryegrass produced 9% more milk

  9. Nitrogen fertilization of grass/clover swards under cutting or grazing by dairy cows

    DEFF Research Database (Denmark)

    Søegaard, Karen

    2009-01-01

    farms over a period of three years. Nitrogen was applied at four rates (0, 75, 150, and 225 kg N year-1) with cutting or grazing regime in Year 1 and Year 2, after establishment. A spring-only application of 150 kg N was compared with four applications during the season, which was the fertilization...... affected. The results indicate different possibilities for strategic fertilization both at farm and field level, and in swards with a high clover content it demonstrates how the clover content can be used as a buffer both for maximizing the N-response and for manipulating the production profile.......Intensively managed perennial ryegrass/white clover (Lolium perenne L. and Trifolium repens L.) swards receive relatively high levels of fertilizer N, and high N surpluses can subsequently be found. The N-fertilization effects on growth, yield, and herbage quality were therefore examined on three...

  10. The 'Big bang' in the Early Iron Age

    Directory of Open Access Journals (Sweden)

    Medović Aleksandar

    2010-01-01

    Full Text Available The Early Iron Age granaries of Tell Gradina upon Bosut exploded in a fire inferno in the 8th century B.C. The result of this catastrophe is 2-5 cm thick layer with mixed carbonized seeds and fruits. Recently, eight samples were taken from Gradina's profile for archaeobotanical analysis. The goal was to obtain basic information on land use and on major crops and weeds of that period. The most abundant were cereals, followed by millets, pulses and oil/fibre plants. The dominant cereals were einkorn (Triticum monococcum and hulled barley (Hordeum vulgare vulgare. Broomcorn millet (Panicum miliaceum was also very important. Pulses were represented with six and oil/fibre plants with three species. Among weeds and ruderals, most common are rye brome (Bromus secalinus, fat hen (Chenopodium album, darnel ryegrass (Lolium temulentum, hairy crabgrass (Digitaria sanguinalis and corncockle (Agrostemma githago.

  11. Effect of forage type, harvesting time and exogenous enzyme application on degradation characteristics measured using in vitro technique

    DEFF Research Database (Denmark)

    Moharrery, Ali; Hvelplund, Torben; Weisbjerg, Martin Riis

    2009-01-01

    Five forage species cut at different harvest times were studied for their degradation characteristics using in vitro digestibility technique. The forage species were two grasses and three legumes growing in two seasons (spring growth and second re-growth). Grass and legume forages were harvested...... at three harvesting times being early (E), middle (M) and late (L), both during the spring growth and the second re-growth. The grasses included perennial ryegrass (Lolium perenne), and festulolium (XFestulolium), and the legumes included white clover (Trifolium repens), red clover (Trifolium pratense......) and neutral detergent fibre (aNDFom) degradation profiles were fitted to an exponential equation. The fractional rate of degradation (c) of DM or aNDFom did vary among the forage species and was highest for the legumes. The potential degradability ranged from 580 to 870 g/kg for DM and from 380 to 900 g...

  12. Effects of clay mineral type and organic matter on the uptake of radiocesium by pasture plants

    International Nuclear Information System (INIS)

    D'Souza, T.J.

    1980-10-01

    Studies were undertaken to examine the influence of interaction of clay minerals and organic matter on the uptake of radiocesium by two pasture plants, namely, ryegrass (Lolium italicum L) and red clover (Trifolium pratense L). The clay minerals used were bentonite (2.1 layer type) and kaolinite (1/1 layer type). Mixtures of clay and sand were prepared with 0.5, 10, 20 and 40 per cent clay and treated with organic matter (forest turf) at 0,5 and 10 per cent of the clay-sand mixtures. Results indicated that 134 Cs uptake by plants grown on the kaolinite-clay medium was greater than that on the bentonite-clay medium at a given organic matter level. Increasing the clay content of mixtures resulted in reduction in 134 Cs uptake by both plant species. The plant uptake of 134 Cs increased with additions of organic matter at a given clay content. (author)

  13. Effect of soil parameters on uranium availability to ryegrass

    International Nuclear Information System (INIS)

    Vandenhove, H.; Van Hees, M.; Wannijn, J.; Wang, L.

    2004-01-01

    When wishing to assess the impact of radioactive contamination on biota or on an ecosystem, knowledge on the physico-chemical conditions governing the radionuclide availability and speciation in the exposure medium and hence its bioavailability and incorporation is indispensable. The present study explores the dominant soil factors (18 soils collected under pasture) ruling uranium mobility and availability to ryegrass and intents to define and assess the extent of the effect. The soils were selected such that they covered a wide range for those parameters hypothesized as being potentially important in determining U-availability (pH, clay content, Fe and Al oxide and hydroxide content, CaCO 3 , organic carbon). Statistical analysis showed that there were no single soil parameters significantly explaining the uranium concentration in the soil solution, nor the uranium concentration in the plants. Soil pH and iron-oxi-hydroxides explained for 60 % the uranium concentration found in the soil solution (which varied with factor 100). Plant U-concentration was mostly affected by the concentration of U in the soil solution, pH and total inorganic carbon content (R 2 =0.71). Observed U-uptake was highest when pH was below 5.3 or around 7 or higher. The next step was to assess the uranium speciation in the soil solution with a Geochemical Speciation Model. Uranium speciation was found important in explaining the U-uptake observed: apparently, uranyl, UO 2 CO 3 -2 and (UO 2 ) 2 CO 3 (OH) 3 - were the U-species being preferentially transported. (author)

  14. Seasonal Variations in Sugar Contents and Microbial Community Behavior in a Ryegrass Soil

    Science.gov (United States)

    Medeiros, P. M.; Fernandes, M. F.; Dick, R. P.; Simoneit, B. R.

    2004-12-01

    Soil is a complex mixture of numerous inorganic and organic constituents that vary in size, shape, chemical constitution and reactivity, and hosts numerous organisms. Total sugars have been estimated to constitute 10% (average) of soil organic matter, occurring in living and decaying organisms, as well as in extracellular materials. The role of sugars in soils is attributed to their influence on soil structure, chemical processes, plant nutrition and microbial activity. The sources of sugars in soils are: a) plants (the primary source); b) animals (the minor source), and c) microorganisms (fungi, bacteria, algae), which decompose the primary plant and animal material, and synthesize the major part of soil carbohydrates. A particular soil sample provides a momentary glimpse into a dynamic system (continuous addition, degradation and synthesis) that might, except for seasonal variations, be in equilibrium. The purpose of this study is to identify and quantify the major sugars in a grass soil and characterize the relationship between their concentration variations and soil microbial behavior over an annual cycle. Soil samples were collected monthly in a ryegrass field close to Corvallis, Oregon, and analyzed by gas chromatography-mass spectrometry as total silylated extracts for sugar composition, and by gas chromatography-flame ionization as fatty acid methyl esters derived from phospholipids and neutral lipids (PLFA and NLFA, respectively). The preliminary results of the first six-month experiment (from January to June, 2004) show that as the ambient temperatures increase the sugar concentrations (glucose, fructose, sucrose and trehalose) also tend to increase in the soil. A decrease is observed in March when precipitation was low during the whole month. The same trend is observed for the active biomass of fungi and bacteria estimated by their fatty acids derived from phospholipids. Fatty acids 18:2ω 6c and 18:3ω 6c are used as fungal biomarkers. Branched (15:0i

  15. Isolation of cDNA encoding a newly identified major allergenic protein of rye-grass pollen: intracellular targeting to the amyloplast.

    Science.gov (United States)

    Singh, M B; Hough, T; Theerakulpisut, P; Avjioglu, A; Davies, S; Smith, P M; Taylor, P; Simpson, R J; Ward, L D; McCluskey, J

    1991-01-01

    We have identified a major allergenic protein from rye-grass pollen, tentatively designated Lol pIb of 31kDa and with pI 9.0. A cDNA clone encoding Lol pIb has been isolated, sequenced, and characterized. Lol pIb is located mainly in the starch granules. This is a distinct allergen from Lol pI, which is located in the cytosol. Lol pIb is synthesized in pollen as a pre-allergen with a transit peptide targeting the allergen to amyloplasts. Epitope mapping of the fusion protein localized the IgE binding determinant in the C-terminal domain. Images PMID:1671715

  16. Highly charged swelling mica reduces Cu bioavailability in Cu-contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Stuckey, Jason W. [Department of Crop and Soil Sciences, Pennsylvania State University, 116 ASI Building, University Park, PA 16802 (United States); Neaman, Alexander [Facultad de Agronomia, P. Universidad Catolica de Valparaiso, Centro Regional de Estudios en Alimentos Saludables (Chile); Ravella, Ramesh; Komarneni, Sridhar [Department of Crop and Soil Sciences, Pennsylvania State University, 116 ASI Building, University Park, PA 16802 (United States); Martinez, Carmen Enid [Department of Crop and Soil Sciences, Pennsylvania State University, 116 ASI Building, University Park, PA 16802 (United States)], E-mail: cem17@psu.edu

    2009-01-15

    This is the first test of a highly charged swelling mica's (Na-2-mica) ability to reduce the plant-absorbed Cu in Cu-contaminated soils from Chile. Perennial ryegrass (Lolium perenne L.) was grown in two acid soils (Sector 2: pH 4.2, total Cu = 172 mg Cu kg{sup -1} and Sector 3: pH 4.2, total Cu = 112 mg Cu kg{sup -1}) amended with 0.5% and 1% (w/w) mica, and 1% (w/w) montmorillonite. At 10 weeks of growth, both mica treatments decreased the shoot Cu of ryegrass grown in Sector 2 producing shoot Cu concentrations above 21-22 mg Cu kg{sup -1} (the phytotoxicity threshold for that species), yet the mica treatments did not reduce shoot Cu concentrations when grown in Sector 3, which were at a typical level. The mica treatments improved shoot growth in Sector 3 by reducing free and extractable Cu to low enough levels where other nutrients could compete for plant absorption and translocation. In addition, the mica treatments improved root growth in both soils, and the 1% mica treatment reduced root Cu in both soils. This swelling mica warrants further testing of its ability to assist re-vegetation and reduce Cu bioavailability in Cu-contaminated surface soils. - In situ remediation of Cu-contaminated soils with a synthetic mica (Na-2-mica) will aid in re-vegetative efforts.

  17. Asparagus decline: Autotoxicity and autotoxic compounds in asparagus rhizomes.

    Science.gov (United States)

    Kato-Noguchi, Hisashi; Nakamura, Keisuke; Ohno, Osamu; Suenaga, Kiyotake; Okuda, Nobuyuki

    2017-06-01

    Asparagus (Asparagus officinalis L.) is a perennial vegetable, but its crop productivity and quality decrease gradually. One possible reason for "asparagus decline" is thought to be the autotoxicity of asparagus. However, the autotoxic property of asparagus rhizomes remains unknown. The objective of this study was to determine the potential role of rhizomes in the autotoxicity of asparagus. An aqueous methanol extract of asparagus rhizomes inhibited the growth of asparagus seedlings and six other test plants in a concentration-dependent manners: garden cress (Lepidum sativum L.), lettuce (Lactuca sativa L.), alfalfa (Medicago sativa L.), ryegrass (Lolium multiflorum Lam.), timothy (Phleum pratense L.) and barnyardgrass (Echinochloa crus-galli (L.) Beauv.). These results suggest that asparagus rhizomes contain autotoxic compounds. The extract was purified through several chromatographic steps with monitoring the autotoxic activity, and p-coumaric acid and iso-agatharesinol were isolated. These compounds inhibited the shoot and root growth of asparagus and two other test plants, garden cress and ryegrass, at concentrations higher than 0.1mM. The concentrations required for 50% inhibition of the root and shoot growth of these test plants ranged from 0.36 to 0.85mM and 0.41-1.22mM for p-coumaric acid and iso-agatharesinol, respectively. Therefore, these compounds may contribute to the autotoxicity caused by asparagus rhizomes and may be involved in "asparagus decline". Copyright © 2017 Elsevier GmbH. All rights reserved.

  18. Genetic variation in cultivars of diploid ryegrass,Lolium perenne andL. multiflorum, at five enzyme systems

    DEFF Research Database (Denmark)

    Østergaard, H.; Nielsen, Gretha; Johansen, H.

    1985-01-01

    was found since at 4 of the 6 loci, Pgi 2, Got 3, Pgm 1 and Pgd 1, the genotypic proportions were in correspondence with the Hardy-Weinberg expectations. This indicated, further, that the genetical interpretations of the banding patterns might be correct. Deviations from Hardy-Weinberg proportions for Acp 1...

  19. Phytoremediation potential of the novel atrazine tolerant Lolium multiflorum and studies on the mechanisms involved

    International Nuclear Information System (INIS)

    Merini, Luciano J.; Bobillo, Cecilia; Cuadrado, Virginia; Corach, Daniel; Giulietti, Ana M.

    2009-01-01

    Atrazine impact on human health and the environment have been extensively studied. Phytoremediation emerged as a low cost, environmental friendly biotechnological solution for atrazine pollution in soil and water. In vitro atrazine tolerance assays were performed and Lolium multiflorum was found as a novel tolerant species, able to germinate and grow in the presence of 1 mg kg -1 of the herbicide. L. multiflorum presented 20% higher atrazine removal capacity than the natural attenuation, with high initial degradation rate in microcosms. The mechanisms involved in atrazine tolerance such as mutation in psbA gene, enzymatic detoxification via P 450 or chemical hydrolysis through benzoxazinones were evaluated. It was demonstrated that atrazine tolerance is conferred by enhanced enzymatic detoxification via P 450 . Due to its atrazine degradation capacity in soil and its agronomical properties, L. multiflorum is a candidate for designing phytoremediation strategies for atrazine contaminated agricultural soils, especially those involving run-off avoiding. - Finding of a novel atrazine-tolerant species, as a potential candidate for phytoremediating herbicide-contaminated agriculture soils and elucidation of the mechanisms involved in tolerance.

  20. Phytoremediation potential of the novel atrazine tolerant Lolium multiflorum and studies on the mechanisms involved

    Energy Technology Data Exchange (ETDEWEB)

    Merini, Luciano J. [Catedra de Microbiologia Industrial y Biotecnologia, Universidad de Buenos Aires (Argentina); Bobillo, Cecilia [Servicio de Huellas Digitales Geneticas, Facultad de Farmacia y Bioquimica, Microbiologia Industrial y Biotecnologia, Universidad de Buenos Aires, Junin 956, BS As (Argentina); Cuadrado, Virginia [Catedra de Microbiologia Industrial y Biotecnologia, Universidad de Buenos Aires (Argentina); Corach, Daniel [Servicio de Huellas Digitales Geneticas, Facultad de Farmacia y Bioquimica, Microbiologia Industrial y Biotecnologia, Universidad de Buenos Aires, Junin 956, BS As (Argentina); Giulietti, Ana M., E-mail: agiule@ffyb.uba.a [Catedra de Microbiologia Industrial y Biotecnologia, Universidad de Buenos Aires (Argentina)

    2009-11-15

    Atrazine impact on human health and the environment have been extensively studied. Phytoremediation emerged as a low cost, environmental friendly biotechnological solution for atrazine pollution in soil and water. In vitro atrazine tolerance assays were performed and Lolium multiflorum was found as a novel tolerant species, able to germinate and grow in the presence of 1 mg kg{sup -1} of the herbicide. L. multiflorum presented 20% higher atrazine removal capacity than the natural attenuation, with high initial degradation rate in microcosms. The mechanisms involved in atrazine tolerance such as mutation in psbA gene, enzymatic detoxification via P{sub 450} or chemical hydrolysis through benzoxazinones were evaluated. It was demonstrated that atrazine tolerance is conferred by enhanced enzymatic detoxification via P{sub 450}. Due to its atrazine degradation capacity in soil and its agronomical properties, L. multiflorum is a candidate for designing phytoremediation strategies for atrazine contaminated agricultural soils, especially those involving run-off avoiding. - Finding of a novel atrazine-tolerant species, as a potential candidate for phytoremediating herbicide-contaminated agriculture soils and elucidation of the mechanisms involved in tolerance.

  1. Dinitroaniline herbicide resistance in a multiple-resistant Lolium rigidum population.

    Science.gov (United States)

    Chen, Jinyi; Yu, Qin; Owen, Mechelle; Han, Heping; Powles, Stephen

    2018-04-01

    The pre-emergence dinitroaniline herbicides (such as trifluralin and pendimethalin) are vital to Australian no-till farming systems. A Lolium rigidum population collected from the Western Australian grain belt with a 12-year trifluralin use history was characterised for resistance to dinitroaniline, acetyl CoA carboxylase (ACCase)- and acetolactate synthase (ALS)-inhibiting herbicides. Target-site resistance mechanisms were investigated. This L. rigidum population exhibited 32-fold resistance to trifluralin, as compared with the susceptible population. It also displayed 12- to 30-fold cross-resistance to other dinitroaniline herbicides (pendimethalin, ethalfluralin and oryzalin). In addition, this population showed multiple resistance to commonly used post-emergence ACCase- and ALS-inhibiting herbicides. Two target-site α-tubulin gene mutations (Val-202-Phe and Thr-239-Ile) previously documented in other dinitroaniline-resistant weed species were identified, and some known target-site mutations in ACCase (Ile-1781-Leu, Asp-2078-Gly and Cys-2088-Arg) and ALS (Pro-197-Gln/Ser) were found in the same population. An agar-based Petri dish screening method was established for the rapid diagnosis of resistance to dinitroaniline herbicides. Evolution of target-site resistance to both pre- and post-emergence herbicides was confirmed in a single L. rigidum population. The α-tubulin mutations Val-202-Phe and Thr-239-Ile, documented here for the first time in L. rigidum, are likely to be responsible for dinitroaniline resistance in this population. Early detection of dinitroaniline herbicide resistance and integrated weed management strategies are needed to maintain the effectiveness of dinitroaniline herbicides. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  2. Identification of two distinct allergenic sites on ryegrass-pollen allergen, Lol p IV.

    Science.gov (United States)

    Jaggi, K S; Ekramoddoullah, A K; Kisil, F T; Dzuba-Fischer, J M; Rector, E S; Sehon, A H

    1989-04-01

    Lol p IV is an important allergen of ryegrass pollen. For the immunochemical identification of antigenic and/or allergenic site(s), murine monoclonal antibodies (MAbs) were prepared against Lol p IV. The hybridoma cell-culture supernatants were screened for anti-Lol p IV antibodies by a combination of ELISA and Western immunoblot analyses. The MAbs were finally purified from ascites on a Mono Q ion-exchange column. In a competitive radioimmunoassay with Lol p IV as the solid phase and 125I-labeled MAbs, it was established that MAbs 90, 91, 92, 93, and 94, although they differed in their relative affinities, recognized in common with one another an epitope designated as antigenic site A, whereas MAb 12 recognized a different epitope referred to as site B. Sites A and B were also demonstrated to constitute allergenic determinants of Lol p IV. Differences in the repertoire of specificities of the human IgE antibodies directed to Lol p IV were also demonstrated. Interestingly, it was found that sera from both allergic as well as from nonatopic individuals had IgG antibodies to sites A and/or B.

  3. Lead uptake from soils by perennial ryegrass and its relation to the supply of an essential element (sulfur)

    Energy Technology Data Exchange (ETDEWEB)

    Jones, L.H.P.; Jarvis, S.C.; Cowling, D.W.

    1973-06-01

    The lead status of 16 soils of England and Wales was studied by pot-culture and soil chemical procedures. Perennial ryegrass was grown on the soils, with and without added sulfur, in a controlled environment cabinet with carbon-filtered air. Plant-available lead comprised uptake in 4 successive harvests of tops plus that in roots at the final harvest. The concentration of lead in the tops of healthy plants, those with adequate sulfur, was lower than in the roots, e.g., at harvest 4 the means were 5.0 and 12.9 ppm, respectively. However, with sulfur-deficient plants the concentration of lead in the tops was often higher than in the roots, the means at harvest 4 being 16.3 and 13.0 ppm respectively. The marked increases in the concentration of lead in the tops of sulfur-deficient plants coincided with decreases in dry-matter yield, but for any one soil the tops of such plants contained similar amounts of lead to those of healthy plants. The led content of the tops was poorly correlated with soil lead whereas that of the roots, in terms of both concentration and total amount, was highly correlated. The amount of lead extracted by 0.5 M BaCl/sub 2/ or 0.05 M EDTA provided a slightly better assessment of availability than total content or the amount extracted by 2.5 percent acetic acid. The solutions of acetic acid, BaCl/sub 2/ and EDTA extracted, on average, 1.0, 16.3 and 32.7 per cent respectively of the total lead in the soils. The greater replacement of lead by the Ba ion than by the H ion (acetic acid) is ascribed to valence and the similar radii of Pb/sup 2 +/ and Ba/sup 2 +/. It is concluded that in soil-grown ryegrass the roots restrict the movement of lead into the tops of high-yielding plants, but when growth is limited by sulfur deficiency the concentration in the tops increases markedly.

  4. De novo assembly of the perennial ryegrass transcriptome using an RNA-seq strategy

    DEFF Research Database (Denmark)

    Farrell, Jacqueline Danielle; Byrne, Stephen; Paina, Cristiana

    2014-01-01

    a homozygous perennial ryegrass genotype can circumvent the challenge of heterozygosity. The goals of this study were to perform RNA-sequencing on multiple tissues from a highly inbred genotype to develop a reference transcriptome. This was complemented with RNA-sequencing of a highly heterozygous genotype...... for SNP calling. Result De novo transcriptome assembly of the inbred genotype created 185,833 transcripts with an average length of 830 base pairs. Within the inbred reference transcriptome 78,560 predicted open reading frames were found of which 24,434 were predicted as complete. Functional annotation...... multiple orthologs. Using the longest unique open reading frames as the reference sequence, 64,242 single nucleotide polymorphisms were found. One thousand sixty one open reading frames from the inbred genotype contained heterozygous sites, confirming the high degree of homozygosity. Conclusion Our study...

  5. Efficacité de quelques herbicides des céréales dans une culture du blé tendre conduite en semis direct

    Directory of Open Access Journals (Sweden)

    Badr HAJJAJ

    2016-12-01

    Full Text Available In order to evaluate the efficacy of 11 cereal herbicides on no till soft wheat, two trials were conducted in Chaouia region during 2014-2015 growing season. Dominant species of weed flora in Sidi El Aidi site were: Bromus rigidus, Lolium rigidum and Avena sterilis. Dominant species of weed flora in Ouled Said site were: Avena sterilis, Centaurea diluta and Papaver rhoeas. The obtained results showed that “Pyroxsulam” and “Mesosulfuron Sodium + Iodosulfuron sodium” gavethe best efficacy on rip gut brome. Prosulfocarb provided excellent control of ryegrass but no effect on ripgut brome or wild oat. Broadleaf herbicides provided moderate to good control. “Mesosulfuron Sodium +Iodosulfuron sodium” need to be completed with an broadleaf herbicide in case centaurea diluta is present. “Pyroxsulam” need to be tank mixed with a broadleaf herbicide to widen its weeds spectrum. Treatment with “Pendimethalin”as pre-emergence herbicide allowed an early complete control of weeds and good crop selectivity.

  6. Transport of sediments, carbon and nutrients in areas of reforestation and grassland based on simulated rainfall

    Directory of Open Access Journals (Sweden)

    Adilson Pinheiro

    2013-08-01

    Full Text Available The objective of this study was to evaluate the soil losses, as well as carbon and chemical samples in runoff through areas of pine (Pinus taeda, eucalyptus (Eucalyptus dunni and a consortium of pasture with oat (Avena stringosa and ryegrass (Lolium multiflorium in the Fragosos river basin, in Concordia, SC. For this, rainfall simulations with mean intensities of 94 mm h-1 were conducted in September and November 2011, in plots of 1 m2 established in the three areas. Runoff, loads carried of the sediment, and carbon and chemical concentrations were quantified in the experiment. The results showed that the concentrations of sediment and organic carbon were higher in the eucalyptus area. The largest concentrations of chemicals for all areas were nitrate, calcium, magnesium and potassium. Total carbon, organic carbon, sediment and nitrate were transported in higher loads in the eucalyptus area. With the exception of nitrate and chloride, the chemical loads carried were higher in the pasture area.

  7. Nitrate Leaching From Grain Maize After Different Tillage Methods and Long/Short Term Cover Cropping

    DEFF Research Database (Denmark)

    Hansen, Elly Møller

    trial initiated in 1968 on a coarse sandy soil. The previous trial included spring sown crops undersown (with or without) perennial ryegrass (Lolium perenne L.) as cover crop, two N-rates (90 and 120 kg N ha-1) and different tillage methods (shallow tillage and ploughing autumn or spring). With maize......) previous history of long-term cover cropping, ii) soil tillage methods, iii) N rates and iv) present short-term use of cover cropping in maize. Preliminary results from 2009 – 2011 suggest that leaching after a history of cover cropping tended to be higher than after no history of cover cropping......, but the effect was insignificant. The effect of tillage and previous N rates were also insignificant but the present use of cover crops had a small but significant decreasing effect on leaching compared to no cover cropping. The cover crop was well established in both years but grew less vigorously during autumn...

  8. Arbuscular mycorrhizal fungal hyphae contribute to the uptake of polycyclic aromatic hydrocarbons by plant roots.

    Science.gov (United States)

    Gao, Yanzheng; Cheng, Zhaoxia; Ling, Wanting; Huang, Jing

    2010-09-01

    The arbuscular mycorrhizal (AM) hyphae-mediated uptake of polycyclic aromatic hydrocarbons (PAHs) by the roots of ryegrass (Lolium multiflorum Lam.) was investigated using three-compartment systems. Glomus mosseae and Glomus etunicatum were chosen, and fluorene and phenanthrene were used as representative PAHs. When roots were grown in un-spiked soils, AM hyphae extended into PAH-spiked soil and clearly absorbed and transported PAHs to roots, resulting in high concentrations of fluorene and phenanthrene in roots. This was further confirmed by the batch equilibration experiment, which revealed that the partition coefficients (K(d)) of tested PAHs by mycorrhizal hyphae were 270-356% greater than those by roots, suggesting the great potential of hyphae to absorb PAHs. Because of fluorene's lower molecular weight and higher water solubility, its translocation by hyphae was greater than that of phenanthrene. These results provide new perspectives on the AM hyphae-mediated uptake by plants of organic contaminants from soil. Copyright 2010 Elsevier Ltd. All rights reserved.

  9. Identification of a gene involved in the regulation of hyphal growth of Epichloë festucae during symbiosis.

    Science.gov (United States)

    Bassett, Shalome A; Johnson, Richard D; Simpson, Wayne R; Laugraud, Aurelie; Jordan, T William; Bryan, Gregory T

    2016-10-01

    Secreted proteins, those involved in cell wall biogenesis, are likely to play a role in communication in the symbiotic interaction between the fungal endophyte Epichloë festucae with perennial ryegrass (Lolium perenne), particularly given the close association between fungal hyphae and the plant cell wall. Our hypothesis was that secreted proteins are likely to be responsible for establishing and maintaining a normal symbiotic relationship. We analyzed an endophyte EST database for genes with predicted signal peptide sequences. Here, we report the identification and characterization of rhgA; a gene involved in the regulation of hyphal growth in planta In planta analysis of ΔrhgA mutants showed that disruption of rhgA resulted in extensive unregulated hyphal growth. This phenotype was fully complemented by insertion of the rhgA gene and suggests that rhgA is important for maintaining normal hyphal growth during symbiosis. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Forage mass and the nutritive value of pastures mixed with forage peanut and red clover

    Directory of Open Access Journals (Sweden)

    Ricardo Lima de Azevedo Junior

    2012-04-01

    Full Text Available The objective of this research was to estimate three pasture-based systems mixed with elephantgrass + spontaneous growth species, annual ryegrass, for pasture-based system 1; elephantgrass + spontaneous growth species + forage peanut, for pasture-based system 2; and elephantgrass + spontaneous growth species + annual ryegrass + red clover, for pasture-based system 3. Elephantgrass was planted in rows 4 m apart from each other. During the cool-season, annual ryegrass was sown in the alleys between the rows of elephantgrass; forage peanut and red clover were sown in the alleys between the elephantgrass according to the respective treatment. The experimental design was totally randomized in the three treatments (pasture-based systems, two replicates (paddocks in completely split-plot time (grazing cycles. Holstein cows receiving 5.5 kg-daily complementary concentrate feed were used in the evaluation. Pre-grazing forage mass, botanical composition and stocking rate were evaluated. Samples of simulated grazing were collected to analyze organic matter (OM, neutral detergent fiber (NDF, crude protein (CP and organic matter in situ digestibility (OMISD. Nine grazing cycles were performed during the experimental period (341 days. The average dry matter values for pre-grazing and stocking rate were 3.34; 3.46; 3.79 t/ha, and 3.28; 3.34; 3.60 AU/ha for each respective pasture-based system. Similar results were observed between the pasture-based systems for OM, NDF, CP and OMISD. Considering forage mass, stocking rate and nutritive value, the pasture-based system intercropped with forage legumes presented better performance.

  11. An Epichloë festucae homologue of MOB3, a component of the STRIPAK complex, is required for the establishment of a mutualistic symbiotic interaction with Lolium perenne

    Science.gov (United States)

    Green, Kimberly A.; Becker, Yvonne; Fitzsimons, Helen L.

    2016-01-01

    Summary In both Sordaria macrospora and Neurospora crassa, components of the conserved STRIPAK (striatin‐interacting phosphatase and kinase) complex regulate cell–cell fusion, hyphal network development and fruiting body formation. Interestingly, a number of Epichloë festucae genes that are required for hyphal cell–cell fusion, such as noxA, noxR, proA, mpkA and mkkA, are also required for the establishment of a mutualistic symbiotic interaction with Lolium perenne. To determine whether MobC, a homologue of the STRIPAK complex component MOB3 in S. macrospora and N. crassa, is required for E. festucae hyphal fusion and symbiosis, a mobC deletion strain was generated. The ΔmobC mutant showed reduced rates of hyphal cell–cell fusion, formed intrahyphal hyphae and exhibited enhanced conidiation. Plants infected with ΔmobC were severely stunted. Hyphae of ΔmobC showed a proliferative pattern of growth within the leaves of Lolium perenne with increased colonization of the intercellular spaces and vascular bundles. Although hyphae were still able to form expressoria, structures allowing the colonization of the leaf surface, the frequency of formation was significantly reduced. Collectively, these results show that the STRIPAK component MobC is required for the establishment of a mutualistic symbiotic association between E. festucae and L. perenne, and plays an accessory role in the regulation of hyphal cell–cell fusion and expressorium development in E. festucae. PMID:27277141

  12. Comportamento ingestivo de cordeiras em pastagem consorciada de inverno sob diferentes intensidades de desfolha Ingestive behavior of lambs on mixed winter pasture under different grazing intensities

    Directory of Open Access Journals (Sweden)

    Carine Lisete Glienke

    2008-11-01

    Full Text Available Avaliou-se a relação entre a estrutura do pasto, as variáveis ambientais e o comportamento ingestivo de cordeiras Ile de France × Texel em pastagem consorciada de aveia-preta (Avena strigosa Schreb., azevém (Lolium multiflorum Lam. e trevo-vermelho (Trifolium pratense L. sob quatro intensidades de desfolha (muito alta, alta, média e baixa. Utilizaram-se pastejos intermitentes considerando a soma térmica de 300 graus-dia como critério para determinar os intervalos de pastejo. As avaliações do comportamento ingestivo foram feitas por meio de observação visual em quatro períodos contínuos de 24 horas realizados no período de maio a outubro de 2006. O maior tempo de pastejo ocorreu na intensidade baixa. Altas intensidades de desfolha ocasionaram aumento da densidade populacional de perfilhos de azevém e não alteraram o peso desses perfilhos. A massa de bocados e a qualidade da dieta selecionada pelas cordeiras foram semelhantes entre as intensidades testadas. Em pastagem de aveia+azevém+trevo-vermelho, quando o intervalo de pastejo é determinado pela soma térmica de 300 graus-dia, a utilização de intensidades de desfolha que variam de baixa a muito alta não altera o comportamento ingestivo de cordeiras. O comportamento ingestivo é afetado pelo ciclo do pasto e pelo fotoperíodo e a seletividade dos animais reduz ao final do período de utilização da pastagem, quando ocorre aumento no tempo de pastejo e na distância percorrida em busca de locais de alimentação.The relationship between the pasture structure, environmental variables and the ingestive behavior of crossbred Ile de France-Texel lambs on a mixed winter pasture of oats (Avena strigosa Schreb., Italian ryegrass (Lolium multiflorum Lam., and red clover (Trifolium pratense L. under four grazing intensities ('very high', 'high', 'average', and 'low' was evaluated. Intermittent grazing was used, considering the thermal sum of 300 degree-days to determine the grazing

  13. Identification of genes involved in a water stress response in timothy and mapping of orthologous loci in perennial ryegrass

    DEFF Research Database (Denmark)

    Jonavičienė, Kristina; Studer, Bruno; Asp, Torben

    2012-01-01

    In order to characterize the response of selected grasses to water stress, relative water content (RWC) in leaves and quantum efficiency of photosystem 2 (Fv/Fm) were measured in Phleum pratense L., P. bertolonii DC. and P. phleoides H. Karst. during 6 d of water stress. The results indicated...... differential responses to water stress among the three Phleum species with higher water deficit sensitivity of P. pratense and P. bertolonii than that of P. phleoides. The cDNA-amplified fragment length polymorphism (cDNA-AFLP) technique was applied to identify differentially expressed genes responding...... to water stress in P. pratense. Cloned and sequenced differentially expressed fragments (DEFs) were used for primer design in order to identify orthologous genes in Lolium perenne L. Twelve genes orthologous to P. pratense DEFs were mapped in the L. perenne mapping population VrnA based on a high...

  14. Designing hybrid grass genomes to control runoff generation

    Science.gov (United States)

    MacLeod, C.; Binley, A.; Humphreys, M.; King, I. P.; O'Donovan, S.; Papadopoulos, A.; Turner, L. B.; Watts, C.; Whalley, W. R.; Haygarth, P.

    2010-12-01

    Sustainable management of water in landscapes requires balancing demands of agricultural production whilst moderating downstream effects like flooding. Pasture comprises 69% of global agricultural areas and is essential for producing food and fibre alongside environmental goods and services. Thus there is a need to breed forage grasses that deliver multiple benefits through increased levels of productivity whilst moderating fluxes of water. Here we show that a novel grass hybrid that combines the entire genomes of perennial ryegrass (Lolium perenne - the grass of choice for Europe’s forage agriculture) and meadow fescue (Festuca pratensis) has a significant role in flood prevention. Field plot experiments established differences in runoff generation with the hybrid cultivar reducing runoff by 50% compared to perennial ryegrass cultivar, and by 35% compared to a meadow fescue cultivar (34 events over two years, replicated randomized-block design, statistically significant differences). This important research outcome was the result of a project that combined plant genetics, soil physics and plot scale hydrology to identify novel grass genotypes that can reduce runoff from grassland systems. Through a coordinated series of experiments examining effects from the gene to plot scale, we have identified that the rapid growth and then turnover of roots in the L. perenne x F. pratensis hybrid is likely to be a key mechanism in reducing runoff generation. More broadly this is an exciting first step to realizing the potential to design grass genomes to achieve both food production, and to deliver flood control, a key ecosystem service.

  15. Cool-Season Turfgrass Species and Cultivars: Response to Simulated Traffic in Central Italy

    Directory of Open Access Journals (Sweden)

    Carlo F. Cereti

    2010-03-01

    Full Text Available Turfgrass species differ greatly in their ability to withstand the abrasion and compaction of traffic. Wear tolerance of turfgrass species and cultivars has been evaluated abroad by many researchers, while only few and partial studies have been conducted in Italy. Field experiment was carried out in Viterbo in 2001, 2002 and 2003 to evaluate the effect of the simulated traffic on 110 varieties belonging to four turfgrass cool-season species: tall fescue (Festuca arundinacea Schreb., fine fescues (Festuca rubra L. ssp. rubra Gaud., ssp. commutata Gaud., ssp. tricophylla Gaud., perennial ryegrass (Lolium perenne L. and Kentucky bluegrass (Poa pratensis L.. Shoot density, visual turfgrass quality and thatch thickness were the major characters recorded to estimate wear tolerance. Traffic was simulated using a device containing three rollers pulled by a small tractor. The traffic simulator weighed 564 kg and applied a pressure of about 3 MPa. Results indicated that perennial ryegrass and tall fescue had high wear tolerance and low statistical variation among cultivars. Kentucky bluegrass showed an average wear tolerance owing to its shoot density and good recovery potential. In spite of their high shoot density, fine fescues exhibited poor wear tolerance because of their scarce resistance to high temperatures which are typical of the Mediterranean climate in late spring and summer. This study enabled a preliminary selection of the most suitable cool-season grasses and cultivars for trafficked and non-trafficked areas in Central Italy and highlighted that different turfgrass species have different wear tolerance mechanisms.

  16. Predicting anthesis date of perennial ryegrass (Lolium perenne L.) with growing degree-days at heading

    DEFF Research Database (Denmark)

    Abel, Simon; Byrne, Stephen; Asp, Torben

    2018-01-01

    The agronomic significance of heading date in crop species is well documented; however, the date of anthesis is often less emphasized even though it has important applications for seed quality and yield. Moreover, the relationship between heading and anthesis is not well defined. We propose that ...

  17. Effects of different fertilizers on growth and nutrient uptake of Lolium multiflorum grown in Cd-contaminated soils.

    Science.gov (United States)

    Liu, Mohan; Li, Yang; Che, Yeye; Deng, Shaojun; Xiao, Yan

    2017-10-01

    This study aimed to explore the effects of different fertilizers and their combinations on growth and nutrient and Cd uptake of Lolium multiflorum. Compared with control treatment, chemical fertilizer, organic manure, and their conjunctions with biofertilizer increased shoot biomass. Biofertilizers were found to cause significant reductions in shoot biomass of plants grown in organic manure-treated and control soil. Decreased soil-available N and P and shoot N and K concentrations in biofertilizer amendment treatments indicated that plant growth and nutrient absorption might be negatively affected under nutrient deficiency conditions. Elevated shoot biomasses contributed to the highest shoot Cd contents in chemical fertilizer and chemical fertilizer + biofertilizer treatments among all treatments. But the maximum translocation efficiency occurred in biofertilizer + chemical fertilizer + organic manure treatment, followed by organic manure and chemical fertilizer + organic manure treatments. Based on the results, we can conclude that the application of only the biofertilizer Bacillus subtilis should be avoided in nutrient-limited soils. Chemical fertilizer application could benefit the amount of Cd in shoots, and organic manure application and its combinations could result in the higher translocation efficiency.

  18. The rumen degradation of nitrogen fractions in annual ryegrass ...

    African Journals Online (AJOL)

    p2486547

    Sample characteristics (particle size, wet or dry sample) clearly influenced the ... reports recommendations have been made for the standardization of the technique .... herbage was immediately taken to the laboratory, mixed and representative ..... contamination of fish meal and meat meal measured by the in situ technique.

  19. Desempenho de forrageiras hibernais sob distintos níveis de luminosidade Performance of hibernal forages under distinct brightness levels

    Directory of Open Access Journals (Sweden)

    Roque Kirchner

    2010-11-01

    Full Text Available Objetivou-se determinar os possíveis efeitos da restrição de luminosidade, obtida com distintas densidades de árvores de Pinnus taeda, sobre a produção e qualidade de: aveia-preta (Avena strigosa Schreb cv. Comum, aveia-branca (Avena sativa L. cv. Fapa 2, azevém (Lolium multiflorum L. cv. Comum, trigo (Triticum aestivum L. duplo propósito cv. BRS Tarumã e ervilhaca peluda (Vicia villosa L.. Avaliaram-se três níveis de luminosidade: a sol aberto (sem presença de árvores de Pinnus taeda, 30% de restrição de radiação (usando espaçamento entre árvores de 15 × 3 m, com 222 árvores/ha e 60% de restrição de radiação (usando espaçamento de 9 × 3 m, com 370 árvores/ha. Foram realizadas avaliações da produção de forragem, da composição química e dos componentes estruturais das plantas, do potencial hídrico das plantas, da umidade do solo, das variáveis microclimáticas e da produção de acículas. O delineamento experimental foi de blocos completos ao acaso, em parcelas subdivididas e três repetições. O azevém foi a espécie mais produtiva em todos os níveis de luminosidade, embora a ervilhaca tenha apresentado a menor redução de produção quando sombreada. Houve maior potencial hídrico nas plantas e maior umidade no solo nos ambientes sombreados, mesmo assim, a produção de forragem reduziu significativamente no sombreamento mais intenso (81%. A composição química e os componentes estruturais de todas as forrageiras estudadas também são afetados pelo aumento da restrição luminosa.Possible effects of brightness restriction, obtained by different Pinnus taeda tree densities, on the production and quality of black oat (Avena strigosa Schreb cv. Common, white oat (Avena sativa L. cv. FAPA 2, annual ryegrass (Lolium multiflorum L. cv. Common, hairy vetch (Vicia villosa, wheat (Triticum aestivum L. cv. dual purpose BRS Tarumã were studied. It was evaluated three brightness levels: 1 - full sunlight with

  20. Complete amino acid sequence of a Lolium perenne (perennial rye grass) pollen allergen, Lol p II.

    Science.gov (United States)

    Ansari, A A; Shenbagamurthi, P; Marsh, D G

    1989-07-05

    The complete amino acid sequence of a Lolium perenne (rye grass) pollen allergen, Lol p II was determined by automated Edman degradation of the protein and selected fragments. Cleavage of the protein by enzymatic and chemical techniques established an unambiguous sequence for the protein. Lol p II contains 97 amino acid residues, with a calculated molecular weight of 10,882. The protein lacks cysteine and glutamine and shows no evidence of glycosylation. Theoretical predictions by Fraga's (Fraga, S. (1982) Can. J. Chem. 60, 2606-2610) and Hopp and Woods' (Hopp, T. P., and Woods, K. R. (1981) Proc. Natl. Acad. Sci. U.S.A. 78, 3824-3828) methods indicate the presence of four hydrophilic regions, which may contribute to sequential or parts of conformational B-cell epitopes. Analysis of amphipathic regions by Berzofsky's method indicates the presence of a highly amphipathic region, which may contain, or contribute to, an Ia/T-cell epitope. This latter segment of Lol p II was found to be highly homologous with an antibody-binding segment of the major rye allergen Lol p I and may explain why immune responsiveness to both the allergens is associated with HLA-DR3.

  1. Effects of Modifiers on Physiological Metabolism of Lolium perenne Seedlings in Diesel-Polluted Soils

    Directory of Open Access Journals (Sweden)

    ZHAO Xuan

    2017-06-01

    Full Text Available The pot experiment for single-factor with diesel oil polluted soil and the pot experiment for three-factor orthogonal with sawdust-ammonium nitrate-monopotassium phosphate under diesel oil polluted soil with salt stress, were performed to analyze the activity of antioxidant enzymes and chlorophyll content in Lolium perenne seedlings, and to explore the physiological response of L. perenne seedlings under diesel oil polluted soil and its regulations. The results showed that, soil diesel pollution significantly decreased the biomass. Compared with control, activity of superoxide dismutases(SOD in leaf decreased significantly at 0.3% and 0.9% soil diesel pollution, peroxidases (POD and catalase(CAT in leaf decreased significantly at 0.6% and 0.9% soil diesel pollution, the root SOD activity increased significantly at 0.9% diesel concentration while the root POD activity decreased significantly at 0.6% and 0.9% soil diesel pollution. As for the salinity soil polluted by diesel oil, the activity of POD and CAT in leaf increased significantly at 10% volume fraction of sawdust, and the content of chlorophyll a and chlorophyll b increased significantly as well. Meanwhile, chlorophyll a and chlorophyll b content increased significantly at 0.3 g·kg-1 amount of ammonium nitrate. Thereby, sawdust and ammonium nitrate addition could effectively improve physiological metabolic of L. perenne seedlings.

  2. The Effect of Applied Organic Fertilizers on the Bioavailability of Heavy Metals in Lolium Perenne, Cultivated on Fly Ash Deposits

    Directory of Open Access Journals (Sweden)

    Smaranda Mâşu

    2011-10-01

    Full Text Available The study aims to monitor the capacity of certain organic fertilizers (volcanic tuff and municipal sludge, applied as such and mixed with volcanic rocks with a high content in clinoptilolite, to determine the covering with vegetation of fly ash deposits resulted from the combustion of lignite in thermal plants. Both biosolids (20 t/ha and volcanic rock with high clinoptilolite content (5 t/ha determined the installation of a vegetative layer and diminished the soil metal bioavailability to the Lolium prerenne plant biomass. When using the organic-zeolite mixture, a synergistic effect is recorded of the two components of the treatment agent and an increase of the biomass with 448%. Moreover, the resulted biomass shows the highest reductions of metal bioaccumulations, of 38-46% for Zn and Fe, of 62% for Cu and between 82-89% for Cr, Ni and Pb.

  3. Effects of the duration and inorganic nitrogen composition of a nutrient-rich patch on soil exploration by the roots of Lolium perenne in a heterogeneous environment.

    Science.gov (United States)

    Nakamura, Ryoji; Kachi, N; Suzuki, J-I

    2010-05-01

    We investigated the growth of and soil exploration by Lolium perenne under a heterogeneous environment before its roots reached a nutrient-rich patch. Temporal changes in the distribution of inorganic nitrogen, i.e., NO(3)(-)-N and NH(4)(+)-N, in the heterogeneous environment during the experimental period were also examined. The results showed that roots randomly explored soil, irrespective of the patchy distribution of inorganic nitrogen and differences in the chemical composition of inorganic nitrogen distribution between heterogeneous and homogeneous environments. We have also elucidated the potential effects of patch duration and inorganic nitrogen distribution on soil exploration by roots and thus on plant growth.

  4. Classification of images of wheat, ryegrass and brome grass species at early growth stages using principal component analysis

    Directory of Open Access Journals (Sweden)

    Golzarian Mahmood R

    2011-09-01

    Full Text Available Abstract Wheat is one of the most important crops in Australia, and the identification of young plants is an important step towards developing an automated system for monitoring crop establishment and also for differentiating crop from weeds. In this paper, a framework to differentiate early narrow-leaf wheat from two common weeds from their digital images is developed. A combination of colour, texture and shape features is used. These features are reduced to three descriptors using Principal Component Analysis. The three components provide an effective and significant means for distinguishing the three grasses. Further analysis enables threshold levels to be set for the discrimination of the plant species. The PCA model was evaluated on an independent data set of plants and the results show accuracy of 88% and 85% in the differentiation of ryegrass and brome grass from wheat, respectively. The outcomes of this study can be integrated into new knowledge in developing computer vision systems used in automated weed management.

  5. Cloning, expression, and immunological characterization of recombinant Lolium perenne allergen Lol p II.

    Science.gov (United States)

    Sidoli, A; Tamborini, E; Giuntini, I; Levi, S; Volonté, G; Paini, C; De Lalla, C; Siccardi, A G; Baralle, F E; Galliani, S

    1993-10-15

    The molecular cloning of the cDNA encoding for an isoallergenic form of Lol p II, a major rye grass (Lolium perenne) pollen allergen, was performed by polymerase chain reaction amplification on mRNA extracted from pollen. The amino acid sequence derived from the cDNA was truncated by 4 and 5 residues at the NH2- and COOH-terminal ends, respectively, and differed only in one position from that previously reported. This cDNA was expressed in Escherichia coli by fusion to the carboxyl terminus of the human ferritin H-chain. The molecule was produced in high yields as a soluble protein and was easily purified. The protein retains the multimeric quaternary structure of ferritin, and it exposes on the surface the allergenic moiety, which can be recognized in Western blotting and in enzyme-linked immunosorbent assay experiments by specific IgE from allergic patients. The recombinant allergen was used to analyze the sera of 26 patients allergic to L. perenne compared with control sera. The results were in good agreement with the values obtained with the radioallergosorbent test assay. In addition, histamine release experiments in whole blood from an allergic patient and skin prick tests showed that the recombinant allergen retains some of the biological properties of the natural compound. These findings indicate that the availability of homogeneous recombinant allergens may be useful for the development of more specific diagnostic and therapeutic procedures. Moreover, this expression system may be of more general interest for producing large amounts of soluble protein domains in E. coli.

  6. Produção de cordeiros em pastagem de azevém e trevo-branco sob diferentes níveis de resíduos de forragem Lamb production in a mixture of italian ryegrass and white clover under different forage mass levels

    Directory of Open Access Journals (Sweden)

    Marcos Weber do Canto

    1999-02-01

    Full Text Available Na presente pesquisa, objetivou-se analisar os efeitos de diferentes níveis de resíduos de forragem na produção de cordeiros. O experimento foi estabelecido em Tupanciretã, região do Planalto Médio do Estado do Rio Grande do Sul, em uma pastagem de azevém cv. Estanzuela 284 (Lolium multiflorum Lam + trevo-branco cv. Yi (Trifolium repens L., submetida a diferentes níveis de resíduo de matéria seca (RMS. O delineamento experimental utilizado foi o completamente casualizado, estudando-se os níveis de RMS mantidos na pastagem de 1.119, 1.320, 1.477, 1.695, 2.146, 2.166, 2.410 e 2.483 kg de matéria seca por hectare (MS/ha. O período experimental foi de 30/09 a 08/12/1992 e os animais utilizados foram cordeiros cruza Ile de France x Corriedale desmamados aos 80 dias. Foram avaliados o ganho de peso médio diário (GMD, ganho de peso vivo/ha (GPV/ha, carga animal, animais dia/ha e a eficiência de conversão de MS em kg de peso vivo de cordeiros. Os resultados obtidos mostraram uma relação linear positiva entre o GMD e GPV/ha com o aumento nos níveis de RMS/ha, observando-se nos níveis de RMS superiores a 2.400 kg um GMD de 0,12 kg/cordeiro/dia e um GPV/ha médio de 497 kg. Não houve relação quanto à carga animal e animais.dia/ha; verificou-se uma relação linear negativa entre a eficiência de conversão de MS com os níveis de RMS estudados. Os resultados demonstram o efeito dos níveis de RMS na resposta animal.The objective of this research was to analyse the effects of different forage mass levels on lamb production. The experiment was conducted in Tupanciretã, Planalto Médio region at the State of Rio Grande do Sul, Brazil, in a mixture of italian ryegrass cv. Estanzuela 284 (Lolium multiflorum Lam. + white clover cv. Yi (Trifolium repens L., under different forage mass (FM levels. The experimental design used was completely randommized, and the FM levels studied were: 1,119, 1,320, 1,477, 1,695, 2,146, 2,166, 2,410 and 2

  7. Response of Thematic Mapper bands to plant water stress

    Science.gov (United States)

    Cibula, W. G.; Zetka, E. F.; Rickman, D. L.

    1992-01-01

    Changes in leaf reflectance as water content decreases have been hypothesized to occur in the 1.55-1.75 and 2.08-2.35 micron wavelength regions. To evaluate this hypothesis, studies were conducted on ryegrass (Lolium multiflorum Lam.) and oats (Avena sativa L.), which were grown in a controlled, outdoor situation. Both fully-watered control beds and water-stressed beds were periodically examined with a spectroradiometer calibrated against a reflectance reference of polytetrafluoroethylene. The observed changes correspond to those predicted by stochastic leaf models employed by other investigators (leaf reflection increases in the 1.55-1.75 micron region as leaf water content decreases). Although the percentage changes in TM bands 1-3 are nearly as great as those found in TM bands 5 and 7, the absolute values of reflectance change are much lower. It is believed that these patterns are probably characteristic of a broad range of vegetation types. In terms of phenomena detection, these patterns should be considered in any practical remote sensing sensor scenario.

  8. Determination of water-extractable nonstructural carbohydrates, including inulin, in grass samples with high-performance anion exchange chromatography and pulsed amperometric detection.

    Science.gov (United States)

    Raessler, Michael; Wissuwa, Bianka; Breul, Alexander; Unger, Wolfgang; Grimm, Torsten

    2008-09-10

    The exact and reliable determination of carbohydrates in plant samples of different origin is of great importance with respect to plant physiology. Additionally, the identification and quantification of carbohydrates are necessary for the evaluation of the impact of these compounds on the biogeochemistry of carbon. To attain this goal, it is necessary to analyze a great number of samples with both high sensitivity and selectivity within a limited time frame. This paper presents a rugged and easy method that allows the isocratic chromatographic determination of 12 carbohydrates and sugar alcohols from one sample within 30 min. The method was successfully applied to a variety of plant materials with particular emphasis on perennial ryegrass samples of the species Lolium perenne. The method was easily extended to the analysis of the polysaccharide inulin after its acidic hydrolysis into the corresponding monomers without the need for substantial change of chromatographic conditions or even the use of enzymes. It therefore offers a fundamental advantage for the analysis of the complex mixture of nonstructural carbohydrates often found in plant samples.

  9. Heavy metal concentrations in plants and different harvestable parts: A soil-plant equilibrium model

    International Nuclear Information System (INIS)

    Guala, Sebastian D.; Vega, Flora A.; Covelo, Emma F.

    2010-01-01

    A mathematical interaction model, validated by experimental results, was developed to modeling the metal uptake by plants and induced growth decrease, by knowing metal in soils. The model relates the dynamics of the uptake of metals from soil to plants. Also, two types of relationships are tested: total and available metal content. The model successfully fitted the experimental data and made it possible to predict the threshold values of total mortality with a satisfactory approach. Data are taken from soils treated with Cd and Ni for ryegrass (Lolium perenne, L.) and oats (Avena sativa L.), respectively. Concentrations are measured in the aboveground biomass of plants. In the latter case, the concentration of metals in different parts of the plants (tillering, shooting and earing) is also modeled. At low concentrations, the effects of metals are moderate, and the dynamics appear to be linear. However, increasing concentrations show nonlinear behaviors. - The model proposed in this study makes possible to characterize the nonlinear behavior of the soil-plant interaction with metal pollution.

  10. Heavy metal concentrations in plants and different harvestable parts: A soil-plant equilibrium model

    Energy Technology Data Exchange (ETDEWEB)

    Guala, Sebastian D. [Instituto de Ciencias, Universidad Nacional de General Sarmiento, Gutierrez 1150, Los Polvorines, Buenos Aires (Argentina); Vega, Flora A. [Departamento de Bioloxia Vexetal e Ciencia do Solo, Facultade de Bioloxia, Universidade de Vigo, Lagoas, Marcosende, 36310 Vigo, Pontevedra (Spain); Covelo, Emma F., E-mail: emmaf@uvigo.e [Departamento de Bioloxia Vexetal e Ciencia do Solo, Facultade de Bioloxia, Universidade de Vigo, Lagoas, Marcosende, 36310 Vigo, Pontevedra (Spain)

    2010-08-15

    A mathematical interaction model, validated by experimental results, was developed to modeling the metal uptake by plants and induced growth decrease, by knowing metal in soils. The model relates the dynamics of the uptake of metals from soil to plants. Also, two types of relationships are tested: total and available metal content. The model successfully fitted the experimental data and made it possible to predict the threshold values of total mortality with a satisfactory approach. Data are taken from soils treated with Cd and Ni for ryegrass (Lolium perenne, L.) and oats (Avena sativa L.), respectively. Concentrations are measured in the aboveground biomass of plants. In the latter case, the concentration of metals in different parts of the plants (tillering, shooting and earing) is also modeled. At low concentrations, the effects of metals are moderate, and the dynamics appear to be linear. However, increasing concentrations show nonlinear behaviors. - The model proposed in this study makes possible to characterize the nonlinear behavior of the soil-plant interaction with metal pollution.

  11. Predicting molybdenum toxicity to higher plants: Estimation of toxicity threshold values

    Energy Technology Data Exchange (ETDEWEB)

    McGrath, S.P., E-mail: steve.mcgrath@bbsrc.ac.u [Soil Science Department, Centre for Soils and Ecosystems Function, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom); Mico, C.; Zhao, F.J.; Stroud, J.L. [Soil Science Department, Centre for Soils and Ecosystems Function, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom); Zhang, H.; Fozard, S. [Division of Environmental Science, Lancaster University, Lancaster LA1 4YQ (United Kingdom)

    2010-10-15

    Four plant species (oilseed rape, Brassica napus L.; red clover, Trifolium pratense L.; ryegrass, Lolium perenne L.; and tomato, Lycopersicon esculentum L.) were tested on ten soils varying widely in soil properties to assess molybdenum (Mo) toxicity. A larger range (66-fold-609-fold) of added Mo concentrations resulting in 50% inhibition of yield (ED{sub 50}) was found among soils than among plant species (2-fold-38-fold), which illustrated that the soils differed widely in the expression of Mo toxicity. Toxicity thresholds based on soil solution Mo narrowed the variation among soils compared to thresholds based on added Mo concentrations. We conclude that plant bioavailability of Mo in soil depends on Mo solubility, but this alone did not decrease the variability in observed toxicity enough to be used in risk assessment and that other soil properties influencing Mo toxicity to plants need to be considered. - Mo toxicity thresholds varied widely in different soils and therefore soil properties need to be taken into account in order to assess the risk of Mo exposure.

  12. Productive performance of Holstein calves finished in feedlot or pasture

    Directory of Open Access Journals (Sweden)

    ANA MARIA O. DIAS

    Full Text Available ABSTRACT The use of animals from dairy farms is an alternative to meat production since it provides an increment of total income for farmers. This study aims to evaluate the performance of Holstein calves finished in two feeding systems (feedlot or pasture. Forty-three animals with 58 days old and 57 kg were divided in two treatments: 23 animals finished in feedlot with corn silage plus concentrate based on corn and soybean meal (40:60; 20 animals kept in cultivated pastures according to the period of the year: Italian ryegrass (Lolium multiflorum and pearl millet (Pennisetum americanum with supplementation with the same feedlot-concentrate at 1% body weight. Animals were slaughtered with 200 kg. Dry matter and nutrient intake were determined, with the use of chromium oxide for estimating pasture intake. Feedlot animals had greater total intake and total digestible nutrients, resulting in higher average daily gain (0.949 vs 0.694 kg day-1. Crude protein intake, neutral detergent fiber and feed conversion did not show significant differences. Holstein calves have improved performance when finished in feedlot.

  13. Impact of Brassica and Lucerne Finishing Feeds and Intramuscular Fat on Lamb Eating Quality and Flavor. A Cross-Cultural Study Using Chinese and Non-Chinese Australian Consumers.

    Science.gov (United States)

    Frank, Damian; Watkins, Peter; Ball, Alex; Krishnamurthy, Raju; Piyasiri, Udayasika; Sewell, James; Ortuño, Jordi; Stark, Janet; Warner, Robyn

    2016-09-14

    Use of forage brassicas (Brassica napus) and lucerne (alfalfa; Medicago sativa) as ruminant feeds has been linked to unacceptable flavors in sheepmeat. Lambs from low and high intramuscular fat sires were allocated to one of four finishing feeds-perennial ryegrass (Lolium perenne), lucerne, and two brassica forages-for a 6 week period. Grilled loins (Longissimus thoracis et lumborum) were subjected to chemical and sensory analysis by a trained panel and also evaluated by non-Chinese and Chinese background Australian consumers. Consumer liking was similar for both groups, and liking was highest for the brassica- and lucerne-finished lamb, especially from high intramuscular fat sires. No evidence of a distinctive lucerne- or brassica-induced flavor taint was measured by the trained panel or gas chromatography-mass spectrometry-olfactometry. The diets influenced the composition of lipids and branched-chain fatty acids in the subcutaneous fat, and the concentration of total branched-chain fatty acids was positively correlated with flavor and overall liking. Significantly higher levels of key aroma volatiles were measured in the higher fat samples.

  14. Cross-resistance to prosulfocarb + S-metolachlor and pyroxasulfone selected by either herbicide in Lolium rigidum.

    Science.gov (United States)

    Busi, Roberto; Powles, Stephen B

    2016-09-01

    Weeds can be a greater constraint to crop production than animal pests and pathogens. Pre-emergence herbicides are crucial in many cropping systems to control weeds that have evolved resistance to selective post-emergence herbicides. In this study we assessed the potential to evolve resistance to the pre-emergence herbicides prosulfocarb + S-metolachlor or pyroxasulfone in 50 individual field Lolium rigidum populations collected in a random survey in Western Australia prior to commercialisation of these pre-emergence herbicides. This study shows for the first time that in randomly collected L. rigidum field populations the selection with either prosulfocarb + S-metolachlor or pyroxasulfone can result in concomitant evolution of resistance to both prosulfocarb + S-metolachlor and pyroxasulfone after three generations. In the major weed L. rigidum, traits conferring resistance to new herbicides can be present before herbicide commercialisation. Proactive and multidisciplinary research (evolutionary ecology, modelling and molecular biology) is required to detect and analyse resistant populations before they can appear in the field. Several studies show that evolved cross-resistance in weeds is complex and often unpredictable. Thus, long-term management of cross-resistant weeds must be achieved through heterogeneity of selection by effective chemical, cultural and physical weed control strategies that can delay herbicide resistance evolution. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  15. Concentrations of PM2.5-10 and PM2.5 and metallic elements around the Schmidt Stream area, in the Sinos River Basin, southern Brazil

    Directory of Open Access Journals (Sweden)

    D. D. Alves

    Full Text Available This research aimed to evaluate the air quality, by determining the concentrations of PM2.5-10, PM2.5 and the metallic elements Al, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn and Hg in the leaf part of ryegrass (Lolium multiflorum in an area close to Schmidt Stream, at the lower section of Sinos River Basin (SRB, in a research campaign of six months, from October 2013 to March 2014. The particles collected in the PM sampling were analyzed by Scanning Electron Microscopy (SEM combined with Energy Dispersive X-ray Spectrometry (EDS, in order to study their morphology and chemical composition. The mean concentration of PM2.5-10 was 9.1 µg m–3, with a range of 2.2 µg m–3 to 15.4 µg m–3 and the mean concentration of PM2.5was 4.7 µg m–3, with a range of 1.9 µg m–3 to 8.2 µg m–3. Concentrations of metallic elements, especially Pb, Cr and Zn, were classified as Class 4 (very high pollution levels, according to the classification proposed by Klumpp et al. (2004. Chemical and morphological analysis of PM revealed the presence of particles of biological origin, soot (Cr, Fe, Ni, Zn, Cd, Hg and Pb, salts (KCl and soil resuspension (Al and Si. The integrated study methodology, employing environmental variables, such as PM and ryegrass, can be of help in the preparation of wide-ranging environmental diagnoses, in addition providing information needed to develop precautionary measures designed to minimize the effects of atmospheric pollution that takes into consideration the environment’s supportive capacity and environmental quality.

  16. Concentrations of PM₂.₅₋₁₀ and PM₂.₅ and metallic elements around the Schmidt Stream area, in the Sinos River Basin, southern Brazil.

    Science.gov (United States)

    Alves, D D; Osório, D M M; Rodrigues, M A S; Illi, J C; Bianchin, L; Benvenuti, T

    2015-12-01

    This research aimed to evaluate the air quality, by determining the concentrations of PM2.5-10, PM2.5 and the metallic elements Al, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn and Hg in the leaf part of ryegrass (Lolium multiflorum) in an area close to Schmidt Stream, at the lower section of Sinos River Basin (SRB), in a research campaign of six months, from October 2013 to March 2014. The particles collected in the PM sampling were analyzed by Scanning Electron Microscopy (SEM) combined with Energy Dispersive X-ray Spectrometry (EDS), in order to study their morphology and chemical composition. The mean concentration of PM2.5-10 was 9.1 µg m(-3), with a range of 2.2 µg m(-3) to 15.4 µg m(-3) and the mean concentration of PM2.5 was 4.7 µg m(-3), with a range of 1.9 µg m(-3) to 8.2 µg m(-3). Concentrations of metallic elements, especially Pb, Cr and Zn, were classified as Class 4 (very high pollution levels), according to the classification proposed by Klumpp et al. (2004). Chemical and morphological analysis of PM revealed the presence of particles of biological origin, soot (Cr, Fe, Ni, Zn, Cd, Hg and Pb), salts (KCl) and soil resuspension (Al and Si). The integrated study methodology, employing environmental variables, such as PM and ryegrass, can be of help in the preparation of wide-ranging environmental diagnoses, in addition providing information needed to develop precautionary measures designed to minimize the effects of atmospheric pollution that takes into consideration the environment's supportive capacity and environmental quality.

  17. The effect of elevated ambient CO2 and temperature increase on rhizosphere of perennial ryegrass (Lolium perenne L.)

    Czech Academy of Sciences Publication Activity Database

    Šantrůčková, Hana; Elhottová, Dana; Loiseau, P.; Soussana, F.

    2000-01-01

    Roč. 46, č. 9 (2000), s. 397-403 ISSN 0370-663X R&D Projects: GA ČR GA206/99/1410 Grant - others:-(EV) EV5V-CT92-0169 Institutional research plan: CEZ:AV0Z6066911; CEZ:MSM 123100004 Subject RIV: EF - Botanics Impact factor: 0.256, year: 2000

  18. Toxicity of eight polycyclic aromatic compounds to red clover (Trifolium pratense), ryegrass (Lolium perenne), and mustard (Sinapsis alba)

    DEFF Research Database (Denmark)

    Sverdrup, L.E.; Krogh, P.H.; Nielsen, T.

    2003-01-01

    three weeks of exposure, seed emergence and seedling weight (fresh weight and dry weight) were determined. Exposure concentrations were verified with chemical analysis. The substances tested were four polycyclic aromatic hydrocarbons (fluoranthene, pyrene, phenanthrene and fluorene), the N-, S-, and O...

  19. Plant tolerance to diesel minimizes its impact on soil microbial characteristics during rhizoremediation of diesel-contaminated soils

    International Nuclear Information System (INIS)

    Barrutia, O.; Garbisu, C.; Epelde, L.; Sampedro, M.C.; Goicolea, M.A.; Becerril, J.M.

    2011-01-01

    Soil contamination due to petroleum-derived products is an important environmental problem. We assessed the impacts of diesel oil on plants (Trifolium repens and Lolium perenne) and soil microbial community characteristics within the context of the rhizoremediation of contaminated soils. For this purpose, a diesel fuel spill on a grassland soil was simulated under pot conditions at a dose of 12,000 mg diesel kg -1 DW soil. Thirty days after diesel addition, T. repens (white clover) and L. perenne (perennial ryegrass) were sown in the pots and grown under greenhouse conditions (temperature 25/18 o C day/night, relative humidity 60/80% day/night and a photosynthetic photon flux density of 400 μmol photon m -2 s -1 ) for 5 months. A parallel set of unplanted pots was also included. Concentrations of n-alkanes in soil were determined as an indicator of diesel degradation. Seedling germination, plant growth, maximal photochemical efficiency of photosystem II (F v /F m ), pigment composition and lipophylic antioxidant content were determined to assess the impacts of diesel on the studied plants. Soil microbial community characteristics, such as enzyme and community-level physiological profiles, were also determined and used to calculate the soil quality index (SQI). The presence of plants had a stimulatory effect on soil microbial activity. L. perenne was far more tolerant to diesel contamination than T. repens. Diesel contamination affected soil microbial characteristics, although its impact was less pronounced in the rhizosphere of L. perenne. Rhizoremediation with T. repens and L. perenne resulted in a similar reduction of total n-alkanes concentration. However, values of the soil microbial parameters and the SQI showed that the more tolerant species (L. perenne) was able to better maintain its rhizosphere characteristics when growing in diesel-contaminated soil, suggesting a better soil health. We concluded that plant tolerance is of crucial importance for the

  20. Dynamics of initial colonization of nonconserved perennial ryegrass by anaerobic fungi in the bovine rumen.

    Science.gov (United States)

    Edwards, Joan E; Kingston-Smith, Alison H; Jimenez, Hugo R; Huws, Sharon A; Skøt, Kirsten P; Griffith, Gareth W; McEwan, Neil R; Theodorou, Michael K

    2008-12-01

    Anaerobic fungi (Neocallimastigales) are active degraders of fibrous plant material in the rumen. However, only limited information is available relating to how quickly they colonize ingested feed particles. The aim of this study was to determine the dynamics of initial colonization of forage by anaerobic fungi in the rumen and the impact of different postsampling wash procedures used to remove loosely associated microorganisms. Neocallimastigales-specific molecular techniques were optimized to ensure maximal coverage before application to assess the population size (quantitative PCR) and composition (automated ribosomal intergenic spacer analysis) of the colonizing anaerobic fungi. Colonization of perennial ryegrass (PRG) was evident within 5 min, with no consistent effect of time or wash procedure on fungal population composition. Wash procedure had no effect on population size unlike time, which had a significant effect. Colonizing fungal population size continued to increase over the incubation period after an initial lag of c. 4 min. This dynamic differs from that reported previously for rumen bacteria, where substantial colonization of PRG occurred within 5 min. The observed delay in colonization of plant material by anaerobic fungi is suggested to be primarily mediated by the time taken for fungal zoospores to locate, attach and encyst on plant material.

  1. Teste de envelhecimento precoce para sementes de azevém, aveia preta e milheto Accelerated aging test for ryegrass black oat grass and pearl millet seeds

    Directory of Open Access Journals (Sweden)

    Danton Camacho Garcia

    1999-06-01

    Full Text Available A viabilidade da aplicação e da padronização do teste de envelhecimento precoce em sementes de azevém, aveia preta e milheto foi verificada em três lotes, para cada espécie, com valores iniciais de germinação semelhantes. As sementes de cada lote foram submetidas ao teste por períodos de 24, 48, 72, 96 e 120 horas, à temperatura de 41°C e 100% de umidade relativa do ar. Em aveia preta, o período de 24 horas estratifica lotes de sementes pelo vigor. Para milheto e azevém, o período de envelhecimento para estratificar lotes de sementes pelo vigor pode ser de 24 a 48 horas. Períodos de 72 a 120 horas são muito drásticos para as três espécies e impedem a estratificação de lotes de sementes pelo vigor.Accelerated aging test standardization for seeds of ryegrass, black oat grass and pearl millet was cheked in three lots, of each specie, with similar initial values of germination. The seeds of each lot were submited to periods of 24, 48, 96 and 120 hours of temperature of 41°C and air relative humidity of 100%. In black oat grass the 24h period stratifies seed vigor among lots. However, for pearl millet and ryegrass the period can be of 24 to 48h. Periods of 72 to 120 hours are very severe to the three species and prevent the seed vigor lots stratification.

  2. Sub-tropical urban environment affecting content and composition of non-structural carbohydrates of Lolium multiflorum ssp. italicum cv. Lema

    International Nuclear Information System (INIS)

    Sandrin, Carla Zuliani; Figueiredo-Ribeiro, Rita de Cassia Leone; Carvalho, Maria Angela Machado de; Carvalho Delitti, Welington Braz; Domingos, Marisa

    2008-01-01

    This study analyzed the relationship between environmental factors, especially air pollution and climatic conditions, and non-structural carbohydrates (NSC) in plants of Lolium multiflorum exposed during 10 consecutive periods of 28 days at a polluted site (Congonhas) and at a reference site in Sao Paulo city (Brazil). After exposure, NSC composition and leaf concentrations of Al, Fe, Cu, Zn, Pb and Cd were measured. The seasonal pattern of NSC accumulation was quite similar in both sites, but plants at Congonhas showed higher concentrations of these compounds, especially fructans of low and medium degree of polymerization. Regression analysis showed that NSC in plants growing at the polluted site were explained by variations on temperature and leaf concentration of Fe (positive effect), as well as relative humidity and particulate material (negative effect). NSC in the standardized grass culture, in addition to heavy metal accumulation, may indicate stressing conditions in a sub-tropical polluted environment. - Particulate matter and air temperature increased non-structural carbohydrates in the standardized biomonitor grass in Sao Paulo

  3. Sub-tropical urban environment affecting content and composition of non-structural carbohydrates of Lolium multiflorum ssp. italicum cv. Lema

    Energy Technology Data Exchange (ETDEWEB)

    Sandrin, Carla Zuliani; Figueiredo-Ribeiro, Rita de Cassia Leone; Carvalho, Maria Angela Machado de [Instituto de Botanica, Caixa Postal 3005, 01061-970 Sao Paulo, SP (Brazil); Carvalho Delitti, Welington Braz [Instituto de Biociencias, Universidade de Sao Paulo, Departamento de Ecologia, Caixa Postal 11461, 05422-970 Sao Paulo, SP (Brazil); Domingos, Marisa [Instituto de Botanica, Caixa Postal 3005, 01061-970 Sao Paulo, SP (Brazil)], E-mail: mmingos@superig.com.br

    2008-12-15

    This study analyzed the relationship between environmental factors, especially air pollution and climatic conditions, and non-structural carbohydrates (NSC) in plants of Lolium multiflorum exposed during 10 consecutive periods of 28 days at a polluted site (Congonhas) and at a reference site in Sao Paulo city (Brazil). After exposure, NSC composition and leaf concentrations of Al, Fe, Cu, Zn, Pb and Cd were measured. The seasonal pattern of NSC accumulation was quite similar in both sites, but plants at Congonhas showed higher concentrations of these compounds, especially fructans of low and medium degree of polymerization. Regression analysis showed that NSC in plants growing at the polluted site were explained by variations on temperature and leaf concentration of Fe (positive effect), as well as relative humidity and particulate material (negative effect). NSC in the standardized grass culture, in addition to heavy metal accumulation, may indicate stressing conditions in a sub-tropical polluted environment. - Particulate matter and air temperature increased non-structural carbohydrates in the standardized biomonitor grass in Sao Paulo.

  4. Recycling of biological sludge for the fertilizing of soils cultivated with Lolium perenne

    Directory of Open Access Journals (Sweden)

    Florica Morariu

    2017-05-01

    Full Text Available The present study has been elaborated with the aim of justifying the high efficiency of in-situ slaughterhouse sludge recycling and its usage in Lolium perenne cultures. Stabilized slaughterhouse sludge was used to complete the high deficiency in nutrients of the poor terrains. Slaughterhouse sludge represents an excessive, final by product from a meat-processing unit in Western Romania. It contains 59.78-90.77% easily bio-degradable organic substances. Moreover, it has compounds containing nitrogen and phosphorus, total N=1.922-3.318%, total P=1107-1126mg•kg-1D.M. The experimental variants have been prepared, having the following characteristics: control variants of non-fertilized soils and variants of soils fertilized with slaughterhouse sludge, 50t•ha-1. The experimental variants used were arranged in a completely randomized block design, with three replicates each. The efficiency of fertilization with slaughterhouse sludge was a 30-35% rise in the quantity of grass harvested vs. the quantities harvested from the control variants. The quantity of Cd and Pb has been determined from the aerial parts of the harvested plants and they were below the maximum limit admitted by the sanitary regulations in Romania. Cr didn’t bio-accumulate in plants at a detection limit. The quantity of other metals determined from the aerial parts of the plants was low: i.e. <10mg•kg-1D.M. for Cu or Ni <50mg•kg-1D.M. for Zn, <150mg•kg-1D.M.for Mn. Green feed harvested from fields fertilized with slaughterhouse sludge can be part of animal nutrition.

  5. Envelhecimento acelerado em sementes de azevém com e sem solução salina e saturada Accelerated aging of ryegrass seeds submitted to saturated salt solution

    Directory of Open Access Journals (Sweden)

    Lilian Madruga de Tunes

    2011-01-01

    Full Text Available O presente trabalho teve por objetivo analisar a metodologia do teste de envelhecimento acelerado para avaliação do potencial fisiológico de sementes de azevém, bem como verificar a possibilidade do uso de solução não saturada e saturada de NaCl como opção para controle da absorção de água pelas sementes durante a realização do teste, sem reduzir sua sensibilidade. Foram utilizados quatro lotes de sementes, submetidos aos testes de germinação, emergência de plântulas, índice de velocidade de emergência e envelhecimento acelerado, empregando-se os períodos de exposição de 24, 48, 72 e 96h, com e sem solução salina (NaCl. A utilização de solução não saturada e saturada de NaCl diminui a absorção de água pelas sementes de azevém durante o teste de envelhecimento acelerado, acarretando uma taxa de deterioração menos acentuada e resultados menos drásticos e mais uniformes. A opção 24h com solução não saturada (SNS só conseguiu estratificar os lotes em dois grupos, não devendo ser indicada como promissora. Assim, deve-se usar a opção 48h com solução saturada de NaCl (SSS, que estratificou em três lotes.The objective of the present study was to evaluate the methodology of the accelerated aging test to evaluate the physiological potential of s ryegrass seeds, as well as verify the possibility of the use of unsaturated and saturated solution of NaCl as an option for control of water uptake by seeds during the test without reducing its sensitivity. Four lots of ryegrass seeds were tested for germination, seedling emergence, speed emergence and accelerated aging (periods of 24, 48, 72 and 96h, with or without the use of saturated and saline solution of NaCl. The use of unsaturated and saturated solution of NaCl reduces water absorption by ryegrass seeds during the accelerated aging test, resulting in a rate of deterioration is less pronounced ,less drastic and more uniform results. Option 24h with

  6. Produtividade de sistemas forrageiros consorciados com amendoim forrageiro ou trevo vermelho Productivity of pastures-based systems mixed to forage peanut or red clover

    Directory of Open Access Journals (Sweden)

    Ricardo Lima de Azevedo Junior

    2012-11-01

    Full Text Available O objetivo desta pesquisa foi avaliar três sistemas forrageiros (SF com capim elefante (CE Pennisetum purpureum Schum., cv. 'MerckeronPinda' + espécies de crescimento espontâneo (ECE + azevém anual (AZ Lolium multiflorum Lam., cv. 'Comum', como SF1; CE + ECE + AZ + amendoim forrageiro (AF Arachis pintoi Krap. e Greg., cv. 'Amarillo', como SF2; e CE + ECE + AZ + trevo vermelho (TV Trifolium pratense L., cv. 'Estanzoela 116', como SF3. O CE foi estabelecido em linhas afastadas a cada 4m. O azevém anual foi estabelecido entre as linhas do CE durante o período hibernal; o TV foi semeado e o AF foi preservado nos respectivos tratamentos. Para avaliação, foram usadas vacas da raça Holandesa que receberam 5,5kg dia-1 como complemento alimentar. Foram avaliadas a taxa de acúmulo diário de matéria seca (TA, a massa de forragem desaparecida (MFD, a matéria seca desaparecida com base em 100kg de peso vivo (MSD e a produção de forragem (PF, as composições botânica e estrutural do CE. O delineamento experimental foi o inteiramente casualizado, com três tratamentos (SF e duas repetições (piquetes em parcelas subdivididas no tempo (pastejo. Durante o período experimental (341 dias, foram efetuados nove ciclos de pastejo. Os valores médios de TA, MFD, MSD e PF foram de 53,16kg ha-1; 36,13%; 2,77kg de matéria seca por 100kg de peso vivo e 17,80t ha-1. Para a variável ECE, houve aumento significativo no SF1. Considerando a carga animal, o SF3 apresentou melhor desempenho.The objective of this research was to evaluate of tree pasture-based systems (PS with elephantgrass (EG Pennisetum purpureum Schum., cv. 'Merckeron Pinda' + spontaneous growing species (SGS, annual ryegrass (RG Lolium multiflorum Lam., cv. 'Comum', for PS1; EG + SGS + forage peanut (FP Arachis pintoi Krap. e Greg., cv. 'Amarillo', for PS2; and EG + SGS + RG + red clover (RC Trifolium pratense L., cv. 'Estanzoela 116', for PS3. EG was planted in lines with a distance of 4m

  7. A comparative study of transfer factors of water, iodine and strontium on rye-grass and clover. Development of a model of evaluation of the limits of foliar contamination by wet deposit

    International Nuclear Information System (INIS)

    Angeletti, Livio; Levi, Emilio.

    1977-07-01

    Transfer factors of water, iodine ( 131 I) and strontium ( 85 Sr) on above-ground parts of rye-grass and clover were determined as a function of aspersion intensities. An analysis of the results showed the effect of aspersion intensities, nature of the chemical element and plant species on the values of transfer factors of iodine and strontium. It also made it possible to propose a simple method of evaluation of contamination limits of the aerial parts of plants by wet deposit, based on transfer values of water on plants only [fr

  8. Impacts of Cover Crops on Water and Nutrient Dynamics in Agroecosystems

    Science.gov (United States)

    Williard, K.; Swanberg, S.; Schoonover, J.

    2013-05-01

    Intensive cropping systems of corn (Zea Mays L.) and soybeans (Glycine max) are commonly leaky systems with respect to nitrogen (N). Reactive N outputs from agroecosystems can contribute to eutrophication and hypoxic zones in downstream water bodies and greenhouse gas (N2O) emissions. Incorporating cover crops into temperate agroecosystem rotations has been promoted as a tool to increase nitrogen use efficiency and thus limit reactive N outputs to the environment. Our objective was determine how cereal rye (Secale cereal L.) and annual ryegrass (Lolium multiflorum) cover crops impact nutrient and soil water dynamics in an intensive corn and soybean cropping rotation in central Illinois. Cover crops were planted in mid to late October and terminated in early April prior to corn or soybean planting. In the spring just prior to cover crop termination, soil moisture levels were lower in the cover crop plots compared to no cover plots. This can be a concern for the subsequent crop in relatively dry years, which the Midwestern United States experienced in 2012. No cover plots had greater nutrient leaching below the rooting zone compared to cover crop areas, as expected. The cover crops were likely scavenging nutrients during the fall and early spring and should provide nutrients to the subsequent crop via decomposition and mineralization of the cover crop residue. Over the long term, cover crop systems should produce greater inputs and cycling of carbon and N, increasing the productivity of crops due to the long-term accumulation of soil organic matter. This study demonstrates that there may be short term trade-offs in reduced soil moisture levels that should be considered alongside the long term nutrient scavenging and recycling benefits of cover crops.

  9. Root characteristics of cover crops and their erosion-reducing potential during concentrated runoff

    Science.gov (United States)

    de Baets, S.; Poesen, J.

    2009-04-01

    In the loam region in central Belgium, a lot of research has been conducted on the effects of cover crops for preventing splash and interrill erosion and on their nutrient pumping effectiveness. As this is a very effective erosion and environment conservation technique, planting cover crops during the winter season is widely applied in the loess belt. Most of these cover crops freeze at the beginning of the winter period. Consequently, the above-ground biomass becomes less effective in protecting the soil from water erosion. Apart from the effects of the above-ground biomass in protecting the soil against raindrop impacts and reducing flow velocities by the retarding effects of their stems, plant roots also play an important role in improving soil strength. Previous research showed that roots contribute to a large extent to the resistance of topsoils against concentrated flow erosion. Unfortunately, information on root properties of common cover crops (e.g. Sinapis alba, Phacelia tanacetifoli, Lolium perenne, Avena sativa, Secale cereale, Raphanus sativus subsp. oleiferus) is very scarce. Therefore, root density distribution with depth and their erosion-reducing effects during concentrated flow erosion were assessed by conducting root auger measurements and concentrated flow experiments at the end of the growth period (December). The preliminary results indicate that the studied cover crops are not equally effective in preventing soil loss by concentrated flow erosion at the end of the growing season. Cover crops with thick roots, such as Sinapis alba and Raphanus sativus subsp. oleiferus are less effective than cover crops with fine-branched roots such as Phacelia tanacetifoli, Lolium perenne (Ryegrass), Avena sativa (Oats) and Secale cereale (Rye) in preventing soil losses by concentrated flow erosion. These results enable soil managers to select the most suitable crops and maximize soil protection.

  10. Comportamento ingestivo diurno de novilhas de corte recebendo níveis de suplemento Diurnal ingestive behavior of beef heifers receiving levels of supplement

    Directory of Open Access Journals (Sweden)

    Stefani Macari

    2007-12-01

    Full Text Available Este trabalho foi conduzido com o objetivo de avaliar a composição botânica da pastagem e o comportamento ingestivo diurno de bezerras de corte recebendo diferentes níveis de suplemento. Os animais foram mantidos em pastagem de aveia preta (Avena strigosa Schreb. e azevém (Lolium multiflorum Lam., recebendo ração comercial nos níveis de 0; 0,3; 0,6 e 0,9% do peso vivo (PV. Em quatro datas, foram registradas as atividades diurnas de pastejo, ruminação, ócio, número de visitas e tempo de permanência no cocho e taxa de bocadas. Com aumento dos níveis de suplemento, houve redução no tempo de pastejo e aumento no tempo de ócio (P0,05. A composição botânica e estrutural da pastagem é influenciada pelos níveis de suplemento utilizados e o ciclo de produção das forrageiras.The trial was conducted aiming to evaluate pasture botanical composition and diurnal ingestive behavior of beef heifers receiving different supplement levels. The animals were kept in black oats (Avena strigosa Schreb. and Italian ryegrass (Lolium multiflorum Lam. pasture, receiving 0; 0.3; 0.6 and 0.9% of live weight (LW of supplement. The supplement utilized was a commercial ration. In four dates were registrated diurnal activities of grazing, ruminating, idle, number of visits and trough permanence time and bite rate. Increasing supplement levels reduced grazing time and increased idle time (P0.05. Botanical and structural composition of pasture were influenced by supplement levels and related with herbage production cycle (P>0.05.

  11. Re-visiting the nutrition of dairy sheep grazing Mediterranean pastures

    Directory of Open Access Journals (Sweden)

    M. Decandia

    2010-04-01

    Full Text Available In the light of recent findings in sheep nutrition and behaviour, the diets of grazing dairy sheep should be based on forages encompassing a variety of complementary nutritional values and containing moderate levels of complementary plant secondary metabolites, until recently regarded as "anti-nutritional". In lactating sheep, pastures of tannin-containing legumes like sulla (Hedysarum coronarium and chicory (Cichorium intybus can be integrated with annual grasses for establishing sustainable artificial pastures under rainfed conditions. Diets based on these forages, while ensuring high milking performance, can mitigate the unbalance of CP to energy ratio of grazing sheep. By grazing sulla and annual or Italian ryegrass (50:50 by area as spatially conterminal monocultures or in timely sequence (complementary grazing sheep eat more and perform better than by grazing the ryegrass pasture only. Concentrate supplementation of lactating sheep should be preferably based on fibrous sources (soyhulls or beet pulps, particularly from mid-lactation onwards and when supplementation levels are high. Milk urea concentration is confirmedly a useful monitoring tool to balance protein nutrition and curb the waste of N at animal and system level.

  12. Bulk density of an alfisol under cultivation systems in a long-term experiment evaluated with gamma ray computed tomography

    International Nuclear Information System (INIS)

    Bamberg, Adilson Luis; Silva, Thiago Rech da; Pauletto, Eloy Antonio; Pinto, Luiz Fernando Spinelli; Lima, Ana Claudia Rodrigues de; Timm, Luis Carlos

    2009-01-01

    The sustainability of irrigated rice (Oryza sativa L.) in lowland soils is based on the use of crop rotation and succession, which are essential for the control of red and black rice. The effects on the soil properties deserve studies, particularly on soil compaction. The objective of this study was to identify compacted layers in an albaqualf under different cultivation and tillage systems, by evaluating the soil bulk density (Ds) with Gamma Ray Computed Tomography (TC). The analysis was carried out in a long-term experiment, from 1985 to 2004, at an experimental station of EMBRAPA Clima Temperado, Capao do Leao, RS, Brazil, in a random block design with seven treatments, with four replications (T1 - one year rice with conventional tillage followed by two years fallow; T2 - continuous rice under conventional tillage; T4 - rice and soybean (Glycine Max L.) rotation under conventional tillage; T5 - rice, soybean and corn (Zea maize L.) rotation under conventional tillage; T6 - rice under no-tillage in the summer in succession to rye-grass (Lolium multiflorum L.) in the winter; T7 - rice under no-tillage and soybean under conventional tillage rotation; T8 - control: uncultivated soil). The Gamma Ray Computed Tomography method did not identify compacted soil layers under no tillage rice in succession to rye-grass; two fallow years in the irrigated rice production system did not prevent the formation of a compacted layer at the soil surface; and in the rice, soybean and corn rotation under conventional tillage two compacted layers were identified (0.0 to 1.5 cm and 11 to 14 cm), indicating that they may restrict the agricultural production in this cultivation system on Albaqualf soils. (author)

  13. A novel two-step method for screening shade tolerant mutant plants via dwarfism

    Directory of Open Access Journals (Sweden)

    Wei Li

    2016-10-01

    Full Text Available When subjected to shade, plants undergo rapid shoot elongation, which often makes them more prone to disease and mechanical damage. Shade-tolerant plants can be difficult to breed; however, they offer a substantial benefit over other varieties in low-light areas. Although perennial ryegrass (Lolium perenne L. is a popular species of turf grasses because of their good appearance and fast establishment, the plant normally does not perform well under shade conditions. It has been reported that, in turfgrass, induced dwarfism can enhance shade tolerance. Here we describe a two-step procedure for isolating shade tolerant mutants of perennial ryegrass by first screening for dominant dwarf mutants, and then screening dwarf plants for shade tolerance. The two-step screening process to isolate shade tolerant mutants can be done efficiently with limited space at early seedling stages, which enables quick and efficient isolation of shade tolerant mutants, and thus facilitates development of shade tolerant new cultivars of turfgrasses. Using the method, we isolated 136 dwarf mutants from 300,000 mutagenized seeds, with 65 being shade tolerant (0.022%. When screened directly for shade tolerance, we recovered only four mutants from a population of 150,000 (0.003% mutagenized seeds. One shade tolerant mutant, shadow-1, was characterized in detail. In addition to dwarfism, shadow-1 and its sexual progeny displayed high degrees of tolerance to both natural and artificial shade. We showed that endogenous gibberellin (GA content in shadow-1 was higher than wild-type controls, and shadow-1 was also partially GA insensitive. Our novel, simple and effective two-step screening method should be applicable to breeding shade tolerant cultivars of turfgrasses, ground covers, and other economically important crop plants that can be used under canopies of existing vegetation to increase productivity per unit area of land.

  14. Comparing Dislodgeable 2,4-D Residues across Athletic Field Turfgrass Species and Time.

    Directory of Open Access Journals (Sweden)

    Matthew D Jeffries

    Full Text Available 2,4-dimethylamine salt (2,4-D is an herbicide commonly applied on athletic fields for broadleaf weed control that can dislodge from treated turfgrass. Dislodge potential is affected by numerous factors, including turfgrass canopy conditions. Building on previous research confirming herbicide-turfgrass dynamics can vary widely between species, field research was initiated in 2014 and 2015 in Raleigh, NC, USA to quantify dislodgeable 2,4-D residues from dormant hybrid bermudagrass (Cynodon dactylon L. x C. transvaalensis and hybrid bermudagrass overseeded with perennial ryegrass (Lolium perenne L., which are common athletic field playing surfaces in subtropical climates. Additionally, dislodgeable 2,4-D was compared at AM (7:00 eastern standard time and PM (14:00 sample timings within a day. Samples collected from perennial ryegrass consistently resulted in greater 2,4-D dislodgment immediately after application (9.4 to 9.9% of applied compared to dormant hybrid bermudagrass (2.3 to 2.9%, as well as at all AM compared to PM timings from 1 to 3 d after treatment (DAT; 0.4 to 6.3% compared to 0.1 to 0.8%. Dislodgeable 2,4-D did not differ across turfgrass species at PM sample collections, with ≤ 0.1% of the 2,4-D applied dislodged from 1 to 6 DAT, and 2,4-D detection did not occur at 12 and 24 DAT. In conclusion, dislodgeable 2,4-D from treated turfgrass can vary between species and over short time-scales within a day. This information should be taken into account in human exposure risk assessments, as well as by turfgrass managers and athletic field event coordinators to minimize 2,4-D exposure.

  15. Assessment of the availability of As and Pb in soils after in situ stabilization.

    Science.gov (United States)

    Zhang, Wanying; Yang, Jie; Li, Zhongyuan; Zhou, Dongmei; Dang, Fei

    2017-10-01

    The in situ stabilization has been widely used to remediate metal-contaminated soil. However, the long-term retaining performance of heavy metals and the associated risk after in situ stabilization remains unclear and has evoked amounting concerns. Here, Pb- or As-contaminated soil was stabilized by a commercial amendment. The availability of Pb and As after in situ stabilization were estimated by ten different in vitro chemical extractions and DGT technique. After amendment application, a significant decline in extractable Pb or As was observed in treatments of Milli-Q water, 0.01 M CaCl 2 , 0.1 M NaNO 3 , 0.05 M (NH 4 ) 2 SO 4 , and 0.43 M HOAc. Potential available metal(loid)s determined by DGT also showed remarkable reduction. Meanwhile, the results of in vivo uptake assays demonstrated that Pb concentrations in shoots of ryegrass Lolium perenne L. declined to 12% of the control samples, comparable to the extraction ratio of 0.1 M NaNO 3 (15.8%) and 0.05 M (NH 4 ) 2 SO 4 (17.3%). For As-contaminated soil, 0.43 M HOAC provided a better estimation of relative phytoavailability (64.6 vs. 65.4% in ryegrass) compared to other extraction methods. We propose that 0.1 M NaNO 3 or 0.05 M (NH 4 ) 2 SO 4 for Pb and 0.43 M HOAc for As may serve as surrogate measures to estimate the lability of metal(loid)s after soil remediation of the tested contaminated soils. Further studies over a wider range of soil types and amendments are necessary to validate extraction methods.

  16. The effects of arbuscular mycorrhizal fungi and root interaction on the competition between Trifolium repens and Lolium perenne.

    Science.gov (United States)

    Ren, Haiyan; Gao, Tao; Hu, Jian; Yang, Gaowen

    2017-01-01

    Understanding the factors that alter competitive interactions and coexistence between plants is a key issue in ecological research. A pot experiment was conducted to test the effects of root interaction and arbuscular mycorrhizal fungi (AMF) inoculation on the interspecies competition between Trifolium repens and Lolium perenne under different proportions of mixed sowing by the combination treatment of two levels of AMF inoculation (inoculation and non-inoculation) and two levels of root interaction (root interaction and non-root interaction). Overall, the aboveground and belowground biomass of T. repens and L. perenne were not altered by AMF inoculation across planting ratios, probably because the fertile soil reduced the positive effect of AMF on plant growth. Both inter- and intraspecies root interaction significantly decreased the aboveground biomass of T. repens , but tended to increase the aboveground biomass of L. perenne across planting ratios, and thus peaked at the 4:4 polyculture. These results showed that T. repens competed poorly with L. perenne because of inter and intraspecies root interaction. Our results indicate that interspecies root interaction regulates the competitive ability of grass L. perenne and legume T. repens in mixtures and further makes great contribution for overyielding. Furthermore, AMF may not be involved in plant-plant interaction in fertile condition.

  17. The effects of arbuscular mycorrhizal fungi and root interaction on the competition between Trifolium repens and Lolium perenne

    Directory of Open Access Journals (Sweden)

    Haiyan Ren

    2017-12-01

    Full Text Available Understanding the factors that alter competitive interactions and coexistence between plants is a key issue in ecological research. A pot experiment was conducted to test the effects of root interaction and arbuscular mycorrhizal fungi (AMF inoculation on the interspecies competition between Trifolium repens and Lolium perenne under different proportions of mixed sowing by the combination treatment of two levels of AMF inoculation (inoculation and non-inoculation and two levels of root interaction (root interaction and non-root interaction. Overall, the aboveground and belowground biomass of T. repens and L. perenne were not altered by AMF inoculation across planting ratios, probably because the fertile soil reduced the positive effect of AMF on plant growth. Both inter- and intraspecies root interaction significantly decreased the aboveground biomass of T. repens, but tended to increase the aboveground biomass of L. perenne across planting ratios, and thus peaked at the 4:4 polyculture. These results showed that T. repens competed poorly with L. perenne because of inter and intraspecies root interaction. Our results indicate that interspecies root interaction regulates the competitive ability of grass L. perenne and legume T. repens in mixtures and further makes great contribution for overyielding. Furthermore, AMF may not be involved in plant–plant interaction in fertile condition.

  18. A simple and fast kinetic assay for the determination of fructan exohydrolase activity in perennial ryegrass (Lolium perenne L.

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    Anna eGasperl

    2015-12-01

    Full Text Available Despite the fact that fructans are the main constituent of water-soluble carbohydrates in forage grasses and cereal crops of temperate climates, little knowledge is available on the regulation of the enzymes involved in fructan metabolism. The analysis of enzyme activities involved in this process has been hampered by the low affinity of the fructan enzymes for sucrose and fructans used as fructosyl donor. Further, the analysis of fructan composition and enzyme activities is restricted to specialized labs with access to suited HPLC equipment and appropriate fructan standards. The degradation of fructan polymers with high degree of polymerization (DP by fructan exohydrolases (FEHs to fructosyloligomers is important to liberate energy in the form of fructan, but also under conditions where the generation of low DP polymers is required. Based on published protocols employing enzyme coupled endpoint reactions in single cuvettes, we developed a simple and fast kinetic 1-FEH assay. This assay can be performed in multi-well plate format using plate readers to determine the activity of 1-FEH against 1-kestotriose, resulting in a significant time reduction. Kinetic assays allow an optimal and more precise determination of enzyme activities compared to endpoint assays, and enable to check the quality of any reaction with respect to linearity of the assay. The enzyme coupled kinetic 1-FEH assay was validated in a case study showing the expected increase in 1-FEH activity during cold treatment. This assay is cost effective and could be performed by any lab with access to a plate reader suited for kinetic measurements and readings at 340 nm, and is highly suited to assess temporal changes and relative differences in 1-FEH activities. Thus, this enzyme coupled kinetic 1-FEH assay is of high importance both to the field of basic fructan research and plant breeding.

  19. Comparative metabolite fingerprinting of the rumen system during colonisation of three forage grass (Lolium perenne L. varieties.

    Directory of Open Access Journals (Sweden)

    Alison H Kingston-Smith

    Full Text Available The rumen microbiota enable ruminants to degrade complex ligno-cellulosic compounds to produce high quality protein for human consumption. However, enteric fermentation by domestic ruminants generates negative by-products: greenhouse gases (methane and environmental nitrogen pollution. The current lack of cultured isolates representative of the totality of rumen microbial species creates an information gap about the in vivo function of the rumen microbiota and limits our ability to apply predictive biology for improvement of feed for ruminants. In this work we took a whole ecosystem approach to understanding how the metabolism of the microbial population responds to introduction of its substrate. Fourier Transform Infra Red (FTIR spectroscopy-based metabolite fingerprinting was used to discriminate differences in the plant-microbial interactome of the rumen when using three forage grass varieties (Lolium perenne L. cv AberDart, AberMagic and Premium as substrates for microbial colonisation and fermentation. Specific examination of spectral regions associated with fatty acids, amides, sugars and alkanes indicated that although the three forages were apparently similar by traditional nutritional analysis, patterns of metabolite flux within the plant-microbial interactome were distinct and plant genotype dependent. Thus, the utilisation pattern of forage nutrients by the rumen microbiota can be influenced by subtleties determined by forage genotypes. These data suggest that our interactomic approach represents an important means to improve forages and ultimately the livestock environment.

  20. Facilitation of a native pest of rice, Stenotus rubrovittatus (Hemiptera: Miridae), by the non-native Lolium multiflorum (Cyperales: Poaceae) in an agricultural landscape.

    Science.gov (United States)

    Yoshioka, Akira; Takada, Mayura; Washitani, Izumi

    2011-10-01

    Source populations of polyphagous pests often occur on host plants other than the economically damaged crop. We evaluated the contribution of patches of a non-native meadow grass, Lolium multiflorum Lam. (Poaceae), and other weeds growing in fallow fields or meadows as source hosts of an important native pest of rice, Stenotus rubrovittatus (Matsumura) (Hemiptera: Miridae), in an agricultural landscape of northern Japan. Periodical censuses of this mirid bug by using the sweeping method, vegetation surveys, and statistical analysis revealed that L. multiflorum was the only plant species that was positively correlated with the density of adult S. rubrovittatus through two generations and thus may be the most stable and important host of the mirid bug early in the season before the colonization of rice paddies. The risk and cost of such an indirect negative effect on a crop plant through facilitation of a native pest by a non-native plant in the agricultural landscape should not be overlooked.

  1. Monoclonal antibodies to the major Lolium perenne (rye grass) pollen allergen Lol p I (Rye I).

    Science.gov (United States)

    Kahn, C R; Marsh, D G

    1986-12-01

    Thirteen monoclonal antibodies (MAbs) were produced against Lol p I (Rye I), the major Lolium perenne (rye grass) pollen allergen. Spleen cells from A/J and SJL mice immunized with highly purified Lol p I (Lol I) were allowed to fuse with cells from the non-secreting Sp2/0-Ag14 myeloma cell line. Each MAb was analyzed for antigenic specificity by radioimmunoassay (RIA) using 125I-Lol I. The epitope specificities of seven of the MAbs were examined by competitive binding against a labelled standard MAb for the Lol I antigen (Ag). The dissociation constant, Kd, of one MAb (No. 3.2) that was studied most extensively was determined by double Ab RIA to be 3.5 X 10(-6) L/M. This MAb recognized the related 27,000-30,000 Group I glycoproteins found in the pollens of nine other species of grass pollens tested, including weak binding to Bermuda grass Group I (Cyn d I), which by conventional analysis using polyclonal anti-Lol I serum shows no detectable binding. Monoclonal antibody No. 3.2 was coupled covalently to Sepharose 4B and used to prepare highly purified Lol I from a partially purified rye pollen extract. Finally, an RIA was developed which permitted the analysis of the Group I components in rye grass and nine other grass pollen species. The latter assay is likely to prove useful in the standardization of grass pollen extracts according to their Group I contents.

  2. Litter Decomposition of Acacia caven (Molina Molina and Lolium multiflorum Lam. in Mediterranean Climate Ecosystems Descomposición de Hojarascas de Acacia caven (Molina Molina y Lolium multiflorum Lam. en Ecosistemas de Clima Mediterráneo

    Directory of Open Access Journals (Sweden)

    Ingrid Martínez G

    2010-09-01

    Full Text Available The ecosystems of the Mediterranean interior dryland of Chile, dominated by an espinal agroecosystem of Acacia caven (Molina Molina, show low productivity as a result of soil degradation. The objective of this study was to evaluate litter decomposition of A. caven and Lolium multiflorum Lam. in espinal ecosystems: well preserved (Wp 50 to 80%, typical (Pd 25 to 50%, and degraded (De with 10 to 25% cover. During 420 d and starting in April 2004 until August 2005, weight loss in litter bags and chemical composition (hemicellulose, cellulose, lignin, non-structural components, ash, N, C, C/N ratio, and P were determined by using near infrared reflectance spectroscopy (NIRS and the Van Soest protocol. Weight loss ranged from 31 to 52% in L. multiflorum and 26 to 40% in A. caven after 420 d. During the chemical decomposition process of L. multiflorum, cellulose degradation was relevant in the labile phase while lignin was important in the recalcitrant phase. On the other hand, non-structural components and cellulose were degraded in the labile phase and lignin in the recalcitrant stage for A. caven. Moreover, both litters improved N concentration during the decomposition process. Espinal ecosystems with higher canopy cover (Pd and Wp had a positive influence, and showed early effects during the decomposition process, especially in the De espinal ecosystem, probably because of the microenvironmental conditions it generated. A better knowledge of the dynamics of litter decomposition in ecosystems was achieved by using both techniques: litter bags and NIRS.Los ecosistemas del secano interior mediterráneo de Chile presentan una baja productividad debido a la degradación de los suelos, dominados por un agroecosistema espinal de Acacia caven (Molina Molina. El objetivo de este estudio fue evaluar la descomposición de hojarascas de A. caven y Lolium multiflorum Lam., en ecosistemas espinales: densos (Wp con cobertura de 50-80%, poco densos (Pd 25-50% y

  3. Produtividade e composição de uva e de vinho de videiras consorciadas com plantas de cobertura Productivity and composition of grapes and wine of vines intercropped with cover crops

    Directory of Open Access Journals (Sweden)

    Jovani Zalamena

    2013-02-01

    (Setaria italica with annual ryegrass (Lolium multiflorum, and buckwheat (Fagopyrum esculentum with oat (Avena sativa, and with perennial fescue (Fetusca sp.. Cover crop managements consisted of transferring or not crop residues from the row to the between rows. Grape yield were higher in vines intercropped with the annual plants, in comparison to the control treatment or to fescue. The management of the cover crops did not affect the evaluated variables. Intercropping did not consistently influence N contents of grapes and wine composition; however, soluble solid contents of must were greater with intercropping treatments compared to control, in the last season. Moreover, vines intercropped with fescue can enable wine with greater content of anthocyanins and total polyphenols.

  4. A 3-D Model of a Perennial Ryegrass Primary Cell Wall and Its Enzymatic Degradation

    Directory of Open Access Journals (Sweden)

    Indrakumar Vetharaniam

    2014-05-01

    Full Text Available We have developed a novel 3-D, agent-based model of cell-wall digestion to improve our understanding of ruminal cell-wall digestion. It offers a capability to study cell walls and their enzymatic modification, by providing a representation of cellulose microfibrils and non-cellulosic polysaccharides and by simulating their spatial and catalytic interactions with enzymes. One can vary cell-wall composition and the types and numbers of enzyme molecules, allowing the model to be applied to a range of systems where cell walls are degraded and to the modification of cell walls by endogenous enzymes. As a proof of principle, we have modelled the wall of a mesophyll cell from the leaf of perennial ryegrass and then simulated its enzymatic degradation. This is a primary, non-lignified cell wall and the model includes cellulose, hemicelluloses (glucuronoarabinoxylans, 1,3;1,4-β-glucans, and xyloglucans and pectin. These polymers are represented at the level of constituent monosaccharides, and assembled to form a 3-D, meso-scale representation of the molecular structure of the cell wall. The composition of the cell wall can be parameterised to represent different walls in different cell types and taxa. The model can contain arbitrary combinations of different enzymes. It simulates their random diffusion through the polymer networks taking collisions into account, allowing steric hindrance from cell-wall polymers to be modelled. Steric considerations are included when target bonds are encountered, and breakdown products resulting from enzymatic activity are predicted.

  5. Coberturas do solo e crescimento da macieira na implantação de um pomar em sistema orgânico de produção Soil coverage and apple tree growth on the establishment of an orchard under organic production system

    Directory of Open Access Journals (Sweden)

    Tânia Regina Pelizza

    2009-09-01

    , pinus sawdust, pinus needle mulch, Andropogon sp mulch, annual ryegrass (Lolium multiflorum, black oat (Avena strigosa, black oat + common vetch (Vicia sativa, black oat + fodder radish (Raphanus sativus, annual ryegrass + white clover (Trifolium repens + spontaneous plant cover, weed mowing. The soil covered by weeds was monthly measured, during the spring/summer season, over the second and third years of the orchard establishment, and this was related to the apple trees growth. The treatments with manual weeding, black plastic film, pinus needle and Andropogon mulch maintained the soil cover by weeds below 20 %. The apple tree height and diameter decreased with the increase of soil cover by weeds, reflecting weeds competition with apple trees.

  6. Sistemas de Alimentação Pós-Desmama de Bezerras de Corte para Acasalamento com 14/15 Meses de Idade Post Weaning Feeding Systems for Beef Heifers to be Bred at 14/15 Months of Age

    Directory of Open Access Journals (Sweden)

    Marta Gomes da Rocha

    2002-07-01

    Full Text Available Este trabalho foi conduzido com o objetivo de avaliar o desempenho de bezerras de corte submetidas a sistemas alternativos de alimentação, no primeiro período outono/inverno pós-desmama, por 88 dias, e, após este período, mantidas sobre pastagem melhorada, até o final do seu primeiro acasalamento, com 14-15 meses de idade. Os sistemas utilizados foram: pastagem- pastejo contínuo em pastagem cultivada de azevém (Lolium multiflorum Lam; suplementação- pastejo contínuo em pastagem natural e suplementação energético-protéica; confinamento- confinamento, a céu aberto, com silagem de sorgo + nitrogênio não-protéico (NNP. Após esse período, as bezerras pastejaram em conjunto pastagens naturais melhoradas compostas por azevém, trevo branco (Trifolium repens e cornichão (Lotus corniculatus. Os dados foram coletados em uma Empresa Agropecuária, localizada em Dom Pedrito, RS, em 395 bezerras de corte pertencentes a três grupos genéticos: Hereford; 3/4 Hereford-1/4 Nelore; 5/8 Hereford-3/8 Nelore. Foram tomados registros de peso vivo (PV, ganho de peso médio diário (GMD e condição corporal (CC. As bezerras mostraram comportamento semelhante quanto ao PV e GMD. A CC foi maior nos animais do grupo confinamento. No início e final da estação de acasalamento, novilhas alimentadas exclusivamente em pastagens tiveram maior PV e CC do que novilhas dos grupos suplementação e confinamento, que não diferiram entre si.The experiment evaluated the performance of beef heifers submitted to three alternatives of autumn-winter feeding systems, during 88 days, and after this period on improved pastures all together until the end of theirs first mating season, with 14-15 months of age. The systems were: Pasture- continuous grazing on cultivated annual ryegrass (L. multiflorum Lam; supplementation- continuous grazing on natural pasture plus energy and protein supplementation; feedlot - feedlot, with sorghum silage plus non- proteic nitrogen

  7. Aided Phytostabilization of Copper Contaminated Soils with L. Perenne and Mineral Sorbents as Soil Amendments

    Science.gov (United States)

    Radziemska, Maja

    2017-09-01

    The present study was designed to assess phytostabilization strategies for the treatment of soil co-contaminated by increasing levels of copper with the application mineral amendments (chalcedonite, zeolite, dolomite). From the results it will be possible to further elucidate the benefits or potential risks derived from the application of different types of mineral amendments in the remediation of a copper contaminated soil. A glasshouse pot experiment was designed to evaluate the potential use of different amendments as immobilizing agents in the aided phytostabilization of Cu-contaminated soil using ryegrass (Lolium perenne L.). The content of trace elements in plants and total in soil, were determined using the method of spectrophotometry. All of the investigated element contents in the tested parts of L. perenne were significantly different in the case of applying mineral amendments to the soil, as well as increasing concentrations of copper. The greatest average above-ground biomass was observed for soil amended with chalcedonite. In this experiment, all analyzed metals accumulated predominantly in the roots of the tested plant. In general, applying mineral amendments to soil contributed to decreased levels of copper concentrations.

  8. Phytotoxic substance with allelopathic activity in Brachiaria decumbens.

    Science.gov (United States)

    Kobayashi, Ai; Kato-Noguchi, Hisashi

    2015-05-01

    The grass Brachiaria decumbens becomes naturalized and quickly dominant in non-native areas. It was hypothesized that phytotoxic substances of plants may contribute to the domination and invasion of the plants. However, no potent phytotoxic substance has been reported in B. decumbens. Therefore, we searched for phytotoxic substances with allelopathic activity in this species. An aqueous methanol extract of B. decumbens inhibited the growth of roots and shoots of cress (Lepidium sativum), lettuce (Lactuca sativa), timothy (Phleum pratense) and ryegrass (Lolium multiflorum) seedlings. The extract was then purified using chromatographic methods and a phytotoxic substance with allelopathic activity was isolated and identified by spectral analysis as (6R,9S)-3-oxo-α-ionol. These results suggest that this compound may contribute to the allelopathic effect caused by the B. decumbens extract and may be in part responsible for the invasion and domination of B. decumbens. Two other Brachiaria species, B. brizantha and a Brachiaria hybrid were also confirmed to contain (6R,9S)-3-oxo-α-ionol. Therefore, this compound may play an important role in the phytotoxicity of the Brachiaria species.

  9. Analysing hydro-mechanical behaviour of reinforced slopes through centrifuge modelling

    Science.gov (United States)

    Veenhof, Rick; Wu, Wei

    2017-04-01

    Every year, slope instability is causing casualties and damage to properties and the environment. The behaviour of slopes during and after these kind of events is complex and depends on meteorological conditions, slope geometry, hydro-mechanical soil properties, boundary conditions and the initial state of the soils. This study describes the effects of adding reinforcement, consisting of randomly distributed polyolefin monofilament fibres or Ryegrass (Lolium), on the behaviour of medium-fine sand in loose and medium dense conditions. Direct shear tests were performed on sand specimens with different void ratios, water content and fibre or root density, respectively. To simulate the stress state of real scale field situations, centrifuge model tests were conducted on sand specimens with different slope angles, thickness of the reinforced layer, fibre density, void ratio and water content. An increase in peak shear strength is observed in all reinforced cases. Centrifuge tests show that for slopes that are reinforced the period until failure is extended. The location of shear band formation and patch displacement behaviour indicate that the design of slope reinforcement has a significant effect on the failure behaviour. Future research will focus on the effect of plant water uptake on soil cohesion.

  10. Study on transfer of cadmium in soil-plant systems with the isotopic dilution method

    International Nuclear Information System (INIS)

    Wu Qitang; Morel, J.L.; Guckert, A.

    1993-01-01

    Experiments were conducted to determine the transfer rate from endogenous and exogenous cadmium in soil to plants. Soils were labelled with 109 Cd and amended with soluble cadmium salt or Cd containing sewage sludge. Ryegrass (Lolium perenne L.) were grown in pots and the effective transfer of cadmium from different sources to shoot of the plant were measured. The soils were also extracted with 0.1 M CaCl 2 , DTPA and 0.1 N HCl. The results showed that the addition of soluble cadmium salt substantially increased the plant cadmium content. Plant absorbed mainly the cadmium from exogenous sources in the soils treated with cadmium. The effective transfer rate of exogenous cadmium was higher than that of endogenous ones, and the soluble salt form was 2 to 3 times higher than that in the sewage sludge. 0.1 M CaCl 2 extracted Cd was significantly correlated with the plant cadmium content. The specific radioactivity of cadmium extracted by this reagent was nearer to the plant cadmium than that extracted by others. 0.1 N HCl extracted cadmium could not be absorbed by plants

  11. The use in grass production of clinoptilolite as an ammonia adsorbent and a nitrogen carrier

    Directory of Open Access Journals (Sweden)

    Milovanović Jelena

    2015-01-01

    Full Text Available The clinoptilolite-rich tuff (NZ from Zlatokop deposit (Vranjska Banja, Serbia has been studied as a nitrogen carrier for grass production. Mechanism of binding ammonium cations present in water solutions by NZ has been examined as well as possibility of adsorption of ammonia released in fresh cattle manure during its fermentation. The NH4+ binding from solutions proceeds via an ion-exchange process which follows the pseudo-second-order kinetics. Adsorption isotherms studied at 298-318 K follow the Freundlich isotherm equation. The NZ readily adsorbs ammonia liberated from manure and an addition of 10 wt.% of NZ to manure can preserve up to 90% of ammonia. The potential benefit of this effect has been examined in greenhouse pot experiments with the Italian ryegrass (Lolium multiflorum, var. Macho using three different types of soil (silty, clayey and sandy. The zeta potential measurements show that stability of their colloidal dispersions differs mutually and that addition of the NZ differently affects the stability and nitrogen cycling. All results indicate that NZ can be applied in grass production. [Projekat Ministarstva nauke Republike Srbije, br. 172018 and Norwegian Programme in Higher Education, Research and Development HERD

  12. Production and chemical composition of grasses and legumes cultivated in pure form, mixed or in consortium

    Directory of Open Access Journals (Sweden)

    Antonio Augusto Cortiana Tambara

    2017-07-01

    Full Text Available The objective of this study was to assess the edible biomass and chemical composition of forages grown on pure form, as a grass mix, and in grass-legume consortia. The following species were tested: white oats (Avena sativa, black oats (Avena strigosa, ryegrass (Lolium multiflorum, forage peanut (Arachis pintoi, white clover (Trifolium repens, and red clover (Trifolium pratense. The experiment consisted of sixteen treatments arranged in a completely randomized design. The parameters measured were total dry matter (PMST, neutral detergent fiber (NDF, acid detergent fiber (ADF, and crude protein (CP. No significant differences in PMST were found among the consortia (p > 0.05. Only the pure cultivated white clover (p > 0.05 was comparable to the consortia in terms of biomass production. The three legumes had the lowest average NDF values (p > 0.05, based on their contributions to the total NDF content of the consortia along the cuts. The ADF content increased for all treatments during the cuts. The results indicate that in pasture, legumes increase protein content, and forage consortia increase both the pasture production and the grazing period. Their chemical composition is adequate for boosting livestock production in pastures.

  13. Accumulation of polycyclic aromatic hydrocarbons from creosote-contaminated soil in selected plants and the oligochaete worm Enchytraeus crypticus

    Energy Technology Data Exchange (ETDEWEB)

    Ann-Sofie Allard; Marianne Malmberg; Alasdair H. Neilson; Mikael Remberger [IVL, Stockholm (Sweden). Swedish Environmental Research Institute

    2005-07-01

    The accumulation of PAHs from a creosote-contaminated soil was examined in laboratory experiments using English ryegrass (Lolium perenne), white clover (Trifolium repens) and radish (Raphanus sativus), and the oligochaete worm Enchytraeus crypticus. Toxicity to the plants and the worms was assessed, and a soil sample mixed with calcined sand was used for accumulation experiments to avoid interference from toxicity in the soil. Accumulation of potentially carcinogenic PAHs varied among the plants, and there was a linear relation between concentrations of PAHs in the soil and in the plants. Correlations between values of the biota-soil accumulation factors and octanol-water partition coefficients, or water solubility varied among the plants and were rather weak, so that lipophilic character or water solubility of the PAHs alone cannot explain PAH accumulation. Accumulation of carcinogenic PAHs from the soil, in the presence of the other PAHs was greatest for Trifolium repens. PAHs were accumulated in the oligochaete worm (Enchytraeus crypticus), and biota-soil accumulation factors exceeded those for the plants. It is suggested that site-specific evaluation of contaminated sites should include not only chemical analysis and evaluation of toxicity but also accumulation of contaminants into biota such as plants and worms.

  14. Dairy cows increase ingestive mastication and reduce ruminative chewing when grazing chicory and plantain.

    Science.gov (United States)

    Gregorini, P; Minnee, E M K; Griffiths, W; Lee, J M

    2013-01-01

    Although the nutritive value of chicory (Cichorium intybus L.) and plantain (Plantago lanceolata L.) has been thoroughly studied, little is known about the grazing behavior of cattle feeding on chicory and plantain swards. The objective of the present study was to assess and describe the grazing behavior of dairy cows as affected by dietary proportions of chicory and plantain fed as monocultures for part of the day. Ninety Holstein-Friesian cows (489±42 kg of body weight; 4.1±0.3 body condition score, and 216±15 d in milk) were randomly assigned to 15 groups (6 cows per group) and grazed according to 7 treatments: control (CTL, 3 groups), perennial ryegrass (Lolium perenne L.) dominant sward (24-h pasture strip); 3 chicory treatments comprising 20, 40, and 60% of the diet, strip-grazing a monoculture of chicory to a fixed postgrazing residual before strip-grazing a perennial ryegrass dominant sward (2 groups of cows per treatment); and 3 plantain treatments comprising 20, 40, and 60% of the diet, strip-grazing a monoculture of plantain to a fixed postgrazing residual before strip-grazing a perennial ryegrass dominant sward (2 groups of cows per treatment). Four focal animals per group were equipped with 3-dimensional motion sensors, which provided the number of steps taken at each minute of the day. These cows were also fitted with automatic jaw-movement recorders that identified bites, mastication during ingestion, chewing during rumination, and determined grazing, rumination and idling times and bouts. Daily grazing time and bouts were not affected by treatments but rumination time differed and was reduced by up to 90 min when cows were allocated to chicory and plantain as 60% of their diet. Ruminative chewing was reduced in cows grazing chicory and plantain by up to 20% in cows allocated to the 60% treatments. Compared with perennial ryegrass, as the dietary proportion of chicory and plantain increased, cows spent more time idling and less time ruminating

  15. Molecular genetics of human immune responsiveness to Lolium perenne (rye) allergen, Lol p III.

    Science.gov (United States)

    Ansari, A A; Freidhoff, L R; Marsh, D G

    1989-01-01

    Lol p II and III are each about 11-kD protein allergens from the pollen of Lolium perenne (rye grass). We have found that human immune responses (IgE and IgG antibodies) to both proteins are significantly associated with HLA-DR3. In addition, the two proteins are cross-reactive with the antibodies in many human sera (about 84% human sera showed the cross-reactivity). We have determined greater than 90% of the amino acid sequences of the two proteins and found that they are at least 54% homologous. Berzofsky found that 75% of the 23 known T cell sites in various proteins had an amphipathic structure. Our analysis by the same method showed that both Lol p II and III have a major region of amphipathicity (at residues 61-67, Lol p III numbering) which might contain sites for binding to an Ia molecule and a T cell receptor. This region is identical between Lol p II and III, except for an Arg-Lys substitution, and could account, in part, for the DR3 association with responsiveness to both molecules. An interesting difference between the two proteins is that immune response to Lol p III is associated with DR5 (in addition to DR3), whereas no DR5 association is found in the case of Lol p II. One possibility is that Lol p III has an additional site which binds to the DR5 Ia molecule. Lol p III indeed has a second highly amphiphathic peptide, 24-30 (Lol p III 24 R P G D T L A 30), which is different and not amphipathic in Lol p II.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Nutritive value and dry matter yield of Annual Ryegrass 121c

    African Journals Online (AJOL)

    Unknown

    Short paper and poster abstracts: 38th Congress of the South African Society of Animal Science. The South African Journal of Animal Science is available online at ... Each plot received nitrogen at a rate of 50 kg/ha after each cut, and potassium at a rate of 50 kg/ha after each second cut. Plots were harvested seven times at ...

  17. Immunochemical studies of Lolium perenne (rye grass) pollen allergens, Lol p I, II, and III.

    Science.gov (United States)

    Ansari, A A; Kihara, T K; Marsh, D G

    1987-12-15

    It was reported earlier that human immune responses to three perennial rye grass (Lolium perenne) pollen allergens, Lol p I, II, and III, are associated with histocompatibility leukocyte antigen (HLA)-DR3. Rye-allergic people are often concordantly sensitive to all three of these allergens. Since earlier studies suggested that these antigens are non-cross-reactive, their immunologic relatedness by double antibody radioimmunoassay (DARIA) was studied in order to understand further the immunochemical basis for the concordant recognition of the three allergens. Direct binding DARIA studies were performed with human sera from 189 allergic subjects. Inhibition DARIA studies were carried out with 17 human sera from grass-allergic patients who were on grass immunotherapy, one goat anti-serum, and six rabbit antisera. None of the sera detected any significant degree of two-way cross-reactivity between Lol p I and II, or between Lol p I and III. However, the degree of two-way cross-reactivity between Lol p II and III exhibited by individual human and animal antisera varied between undetectable and 100%. In general, the degree of cross-reactivity between Lol p II and III was higher among human sera than among animal sera. Taken together with earlier findings that antibody responses to Lol p I, II and III are associated with HLA-HDR3, and that most Lol p II and III responders are also Lol p I responders, but not vice versa, our present results suggest the following: the HLA-DR3-encoded Ia molecule recognizes a similar immunodominant Ia recognition site (agretope) shared between Lol p I and Lol p II and/or III; in addition, Lol p I appears to contain unique Ia recognition site(s) not present in Lol p II and III. However, further epitope analyses are required to investigate these possibilities.

  18. Exogenous Application of Citric Acid Ameliorates the Adverse Effect of Heat Stress in Tall Fescue (Lolium arundinaceum)

    Science.gov (United States)

    Hu, Longxing; Zhang, Zhifei; Xiang, Zuoxiang; Yang, Zhijian

    2016-01-01

    Citric acid may be involved in plant response to high temperature. The objective of this study was to investigate whether exogenous citric acid could improve heat tolerance in a cool-season turfgrass species, tall fescue (Lolium arundinaceum), and to determine the physiological mechanisms of citric acid effects on heat stress tolerance. The grasses were subjected to four citric acid levels (0, 0.2, 2, and 20 mM) and two temperature levels (25/20 and 35/30 ± 0.5°C, day/night) treatments in growth chambers. Heat stress increased an electrolyte leakage (EL) and malonaldehyde (MDA) content, while reduced plant growth, chlorophyll (Chl) content, photochemical efficiency (Fv/Fm), root activity and antioxidant enzyme activities (superoxide dismutase, SOD; catalase, CAT; peroxidase, POD). External citric acid alleviated the detrimental effects of heat stress on tall fescue, which was evidenced by decreased EL and MDA content, and improved plant growth under stress conditions. Additionally, the reduction in Chl content, Fv/Fm, SOD, POD, CAT and root activity were ameliorated in citric acid treated plants under heat stressed conditions. High temperature induced the expression of heat shock protein (HSP) genes, which exhibited greater expression levels after citric acid treatment under heat stress. These results suggest that exogenous citric acid application may alleviate growth and physiological damage caused by high temperature. In addition, the exogenously applied citric acid might be responsible for maintaining membrane stability, root activity, and activation of antioxidant response and HSP genes which could contribute to the protective roles of citric acid in tall fescue responses to heat stress. PMID:26925085

  19. Exogenous Application of Citric Acid Ameliorates the Adverse Effect of Heat Stress in Tall Fescue (Lolium arundinaceum).

    Science.gov (United States)

    Hu, Longxing; Zhang, Zhifei; Xiang, Zuoxiang; Yang, Zhijian

    2016-01-01

    Citric acid may be involved in plant response to high temperature. The objective of this study was to investigate whether exogenous citric acid could improve heat tolerance in a cool-season turfgrass species, tall fescue (Lolium arundinaceum), and to determine the physiological mechanisms of citric acid effects on heat stress tolerance. The grasses were subjected to four citric acid levels (0, 0.2, 2, and 20 mM) and two temperature levels (25/20 and 35/30 ± 0.5°C, day/night) treatments in growth chambers. Heat stress increased an electrolyte leakage (EL) and malonaldehyde (MDA) content, while reduced plant growth, chlorophyll (Chl) content, photochemical efficiency (Fv/Fm), root activity and antioxidant enzyme activities (superoxide dismutase, SOD; catalase, CAT; peroxidase, POD). External citric acid alleviated the detrimental effects of heat stress on tall fescue, which was evidenced by decreased EL and MDA content, and improved plant growth under stress conditions. Additionally, the reduction in Chl content, Fv/Fm, SOD, POD, CAT and root activity were ameliorated in citric acid treated plants under heat stressed conditions. High temperature induced the expression of heat shock protein (HSP) genes, which exhibited greater expression levels after citric acid treatment under heat stress. These results suggest that exogenous citric acid application may alleviate growth and physiological damage caused by high temperature. In addition, the exogenously applied citric acid might be responsible for maintaining membrane stability, root activity, and activation of antioxidant response and HSP genes which could contribute to the protective roles of citric acid in tall fescue responses to heat stress.

  20. Potencial de quatro espécies herbáceas forrageiras para fitorremediação de solo contaminado por arsênio Potential of four herbaceous forage species for phytoremediation of a soil contaminated with arsenic

    Directory of Open Access Journals (Sweden)

    Roseli Freire de Melo

    2009-04-01

    fitoestabilização e, ou, na revegetação de áreas contaminadas por As, uma vez que apresentaram tolerância a esse elemento. Por se tratar de espécies forrageiras, quando utilizadas para esses fins, cuidados especiais são necessários, como o isolamento da área, para evitar a entrada do elemento na cadeia trófica.The decontamination of soils and substrates contaminated with arsenic through phytoremediation techniques has attracted increasing interest of researchers and specialists of environmental sciences. This study aimed to evaluate the potential of the species townsville stylo (Stylosanthes humilis HBK, forage peanut (Arachis pintoi Krapov. & Gregory, oat (Avena strigosa Schreb, and ryegrass (Lolium multiflorum Lam. for phytoremediation of arsenic-contaminated soils. Samples of a Red Yellowh Latossol (Oxisol were incubated with different doses of arsenic (0; 50; 100 and 200 mg dm-3. After this incubation period, the four species were sown and, after germination, soil samples were fertilized accordingly. Sixty five days after sowing, plants were evaluated for height and biomass weight of roots and shoots. Arsenic content in young, intermediate, and old leaves, stem and roots and the As-translocation index (IT were determined. By regression analysis we estimated the critical contents for available arsenic (TC in soil which reduced the biomass production by 50 %. The species differed in As-tolerance; no morphologic symptoms of As toxicity were observed for ryegrass, forage peanut and townsville stylo. The TC values for oat and ryegrass were high. In forage peanut and townsville stylo plants the absorption and shoot translocation of arsenic were higher, but the potential of forage peanut for phytoremediation programs is greater. Ryegrass, peanut and stylo plants can be used in phytostabilization and / or the revegetation of As-contaminated areas. When forage species are used with phytoremediation purposes, special care is needed, such as the isolation of the area, to

  1. Complete primary structure of a Lolium perenne (perennial rye grass) pollen allergen, Lol p III: comparison with known Lol p I and II sequences.

    Science.gov (United States)

    Ansari, A A; Shenbagamurthi, P; Marsh, D G

    1989-10-17

    The complete amino acid sequence of a Lolium perenne (rye grass) pollen allergen, Lol p III, determined by the automated Edman degradation of the protein and its selected fragments, is reported in this paper. Cleavage by enzymatic and chemical techniques established unambiguously the sequence for this 97-residue protein (Mr = 10,909), which lacks cysteine and shows no evidence of glycosylation. The sequence of Lol p III is very similar to that of another L. perenne allergen, Lol p II, which was sequenced recently; of the 97 positions in the two proteins, 57 are occupied by identical amino acids (59% identity). In addition, both allergens share a similar structure with an antibody-binding fragment of a third L. perenne allergen, Lol p I. Since human antibody responsiveness to all these three allergens is associated with HLA-DR3, and since the structure common to the three molecules shows high degrees of amphipathicity in Lol p II and III, we speculate that this common segment in the three molecules might contain or contribute to the respectively Ia/T-cell sites.

  2. Exploring the potential of phyllosilicate minerals as potassium fertilizers using sodium tetraphenylboron and intensive cropping with perennial ryegrass

    Science.gov (United States)

    Li, Ting; Wang, Huoyan; Wang, Jing; Zhou, Zijun; Zhou, Jianmin

    2015-01-01

    In response to addressing potassium (K) deficiency in soil and decreasing agricultural production costs, the potential of K-bearing phyllosilicate minerals that can be directly used as an alternative K source has been investigated using sodium tetraphenylboron (NaTPB) extraction and an intensive cropping experiment. The results showed that the critical value of K-release rate and leaf K concentration was 3.30 g kg−1 h−1 and 30.64 g (kg dry matter)−1, respectively under the experimental conditions. According to this critical value, the maximum amount of released K that could be utilized by a plant with no K deficiency symptoms was from biotite (27.80 g kg−1) and vermiculite (5.58 g kg−1), followed by illite, smectite and muscovite with 2.76, 0.88 and 0.49 g kg−1, respectively. Ryegrass grown on phlogopite showed K deficiency symptoms during the overall growth period. It is concluded that biotite and vermiculite can be directly applied as a promising and sustainable alternative to the use of classical K fertilizers, illite can be utilized in combination with soluble K fertilizers, whereas muscovite, phlogopite and smectite may not be suitable for plant growth. Further field experiments are needed to assess the use of these phyllosilicate minerals as sources of K fertilizer. PMID:25782771

  3. Non-ionic Surfactants and Non-Catalytic Protein Treatment on Enzymatic Hydrolysis of Pretreated Creeping Wild Ryegrass

    Science.gov (United States)

    Zheng, Yi; Pan, Zhongli; Zhang, Ruihong; Wang, Donghai; Jenkins, Bryan

    Our previous research has shown that saline Creeping Wild Ryegrass (CWR), Leymus triticoides, has a great potential to be used for bioethanol production because of its high fermentable sugar yield, up to 85% cellulose conversion of pretreated CWR. However, the high cost of enzyme is still one of the obstacles making large-scale lignocellulosic bioethanol production economically difficult. It is desirable to use reduced enzyme loading to produce fermentable sugars with high yield and low cost. To reduce the enzyme loading, the effect of addition of non-ionic surfactants and non-catalytic protein on the enzymatic hydrolysis of pretreated CWR was investigated in this study. Tween 20, Tween 80, and bovine serum albumin (BSA) were used as additives to improve the enzymatic hydrolysis of dilute sulfuric-acid-pretreated CWR. Under the loading of 0.1 g additives/g dry solid, Tween 20 was the most effective additive, followed by Tween 80 and BSA. With the addition of Tween 20 mixed with cellulase loading of 15 FPU/g cellulose, the cellulose conversion increased 14% (from 75 to 89%), which was similar to that with cellulase loading of 30 FPU/g cellulose and without additive addition. The results of cellulase and BSA adsorption on the Avicel PH101, pretreated CWR, and lignaceous residue of pretreated CWR support the theory that the primary mechanism behind the additives is prevention of non-productive adsorption of enzymes on lignaceous material of pretreated CWR. The addition of additives could be a promising technology to improve the enzymatic hydrolysis by reducing the enzyme activity loss caused by non-productive adsorption.

  4. Genetic Gain and Inbreeding from Genomic Selection in a Simulated Commercial Breeding Program for Perennial Ryegrass

    Directory of Open Access Journals (Sweden)

    Zibei Lin

    2016-03-01

    Full Text Available Genomic selection (GS provides an attractive option for accelerating genetic gain in perennial ryegrass ( improvement given the long cycle times of most current breeding programs. The present study used simulation to investigate the level of genetic gain and inbreeding obtained from GS breeding strategies compared with traditional breeding strategies for key traits (persistency, yield, and flowering time. Base population genomes were simulated through random mating for 60,000 generations at an effective population size of 10,000. The degree of linkage disequilibrium (LD in the resulting population was compared with that obtained from empirical studies. Initial parental varieties were simulated to match diversity of current commercial cultivars. Genomic selection was designed to fit into a company breeding program at two selection points in the breeding cycle (spaced plants and miniplot. Genomic estimated breeding values (GEBVs for productivity traits were trained with phenotypes and genotypes from plots. Accuracy of GEBVs was 0.24 for persistency and 0.36 for yield for single plants, while for plots it was lower (0.17 and 0.19, respectively. Higher accuracy of GEBVs was obtained for flowering time (up to 0.7, partially as a result of the larger reference population size that was available from the clonal row stage. The availability of GEBVs permit a 4-yr reduction in cycle time, which led to at least a doubling and trebling genetic gain for persistency and yield, respectively, than the traditional program. However, a higher rate of inbreeding per cycle among varieties was also observed for the GS strategy.

  5. Genetic Gain and Inbreeding from Genomic Selection in a Simulated Commercial Breeding Program for Perennial Ryegrass.

    Science.gov (United States)

    Lin, Zibei; Cogan, Noel O I; Pembleton, Luke W; Spangenberg, German C; Forster, John W; Hayes, Ben J; Daetwyler, Hans D

    2016-03-01

    Genomic selection (GS) provides an attractive option for accelerating genetic gain in perennial ryegrass () improvement given the long cycle times of most current breeding programs. The present study used simulation to investigate the level of genetic gain and inbreeding obtained from GS breeding strategies compared with traditional breeding strategies for key traits (persistency, yield, and flowering time). Base population genomes were simulated through random mating for 60,000 generations at an effective population size of 10,000. The degree of linkage disequilibrium (LD) in the resulting population was compared with that obtained from empirical studies. Initial parental varieties were simulated to match diversity of current commercial cultivars. Genomic selection was designed to fit into a company breeding program at two selection points in the breeding cycle (spaced plants and miniplot). Genomic estimated breeding values (GEBVs) for productivity traits were trained with phenotypes and genotypes from plots. Accuracy of GEBVs was 0.24 for persistency and 0.36 for yield for single plants, while for plots it was lower (0.17 and 0.19, respectively). Higher accuracy of GEBVs was obtained for flowering time (up to 0.7), partially as a result of the larger reference population size that was available from the clonal row stage. The availability of GEBVs permit a 4-yr reduction in cycle time, which led to at least a doubling and trebling genetic gain for persistency and yield, respectively, than the traditional program. However, a higher rate of inbreeding per cycle among varieties was also observed for the GS strategy. Copyright © 2016 Crop Science Society of America.

  6. Sheep Excreta as Source of Nitrous Oxide in Ryegrass Pasture in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Michely Tomazi

    2015-10-01

    Full Text Available ABSTRACT Livestock urine and dung are important components of the N cycle in pastures, but little information on its effect on soil nitrous oxide (N2O emissions is available. We conducted a short-term (39-day trial to quantify the direct N2O-N emissions from sheep excreta on an experimental area of ryegrass pasture growing on a Typic Paleudult in southern Brazil. Four rates of urine-N (161, 242, 323, and 403 kg ha-1 N and one of dung-N (13 kg ha-1 N were applied, as well as a control plot receiving no excreta. The N2O-N emission factor (EF = % of added N released as N2O-N for urine and dung was calculated, taking into account the N2O fluxes in the field, over a period of 39 days. The EF value of the urine and dung was used to estimate the emissions of N2O-N over a 90-day period of pasture in the winter under two grazing intensities (2.5 or 5.0 times the herbage intake potential of grazing lambs. The soil N2O-N fluxes ranged from 4 to 353 µg m-2h-1. The highest N2O-N fluxes occurred 16 days after application of urine and dung, when the highest soil nitrate content was also recorded and the water-filled pore space exceeded 60 %. The mean EF for urine was 0.25 % of applied N, much higher than that for dung (0.06 %. We found that N2O-N emissions for the 90-day winter pasture period were 0.54 kg ha-1 for low grazing intensity and 0.62 kg ha-1 for moderate grazing intensity. Comparison of the two forms of excreta show that urine was the main contributor to N2O-N emissions (mean of 36 %, whereas dung was responsible for less than 0.1 % of total soil N2O-N emissions.

  7. Forage yield and nutritive value of Elephant grass, Italian ryegrass and spontaneous growing species mixed with forage peanut or red clover

    Directory of Open Access Journals (Sweden)

    Michelle Schalemberg Diehl

    2014-10-01

    Full Text Available The objective of this research was to evaluate of three grazing systems (GS with elephant grass (EG, Italian ryegrass (IR + spontaneous growing species (SGS; EG + IR + SGS + forage peanut (FP; and EG + IR + SGS + red clover (RC, during the winter and summer periods in rotational grazing with dairy cattle. Experimental design was completely randomized with three treatments, two replicates with repeated measures. Lactating Holstein cows receiving 1% BW-daily feed supplement with concentrate were used in the evaluation. Eight grazing cycles were performed during the experimental period. The values of pre forage mass and stocking rate were 2.52, 2.60 and 2.99 t ha-1 and 2.64, 2.77 and 3.14 animal unit ha-1, respectively for GS. Samples of forage were collected by hand-plucking technique to analyze the crude protein (CP, neutral detergent fiber (NDF, in situ dry matter digestibility (ISDMD, in situ organic matter digestibility (ISOMD of forage present between rows of elephant grass, in the rows of elephant grass and the legumes. Higher value of CP, ISOMD and lower of NDF were observed for the grazing systems mixed with legumes forage.

  8. Quarterly, Bi-annual and Annual Reports

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Quarterly, Bi-annual and Annual Reports are periodic reports issued for public release. For the deep set fishery these reports are issued quarterly and anually....

  9. Produção animal em pastagem natural e pastagem sobre-semeada com espécies de estação fria com e sem o uso de glyphosate = Animal production in natural pasture and pasture overseeded with cool season species with and without the use of glyphosate

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Nogueira Martins

    2008-04-01

    Full Text Available Objetivou-se avaliar a produção animal de novilhos e vegetal de campo natural e de campo natural sobre-semeado com azevém (Lolium multiflorum, trevo branco (Trifolium repens e cornichão (Lotus corniculatus com e sem a utilização do herbicida glyphosate. Os tratamentos foram: CN – campo nativo, com roçada anual; CNI – campo nativo com sobre-semeadura, adubação e roçada anual; G1 – Idem ao CNI com aplicação de herbicida no primeiro ano; G3 – idem ao G1 com supressão da vegetação natural com herbicida no segundo e terceiro ano; GA3 – Idem ao G3 com adubação duplicada nos três anos. O delineamento experimental foi blocos completamente casualizados com duas repetições. Os resultados apresentados são do terceiro anode avaliação. Para ganho médio diário, houve diferenças (p £ 0,1 entre tratamentos e períodos, que variaram de 0,214 kg animal-1 dia-1 em CN a 1,406 para os tratamentos com introdução de espécies. Quanto à variável ganho por área, os ganhos variaram de 84 a 410 kg PV ha-1. As cargas variaram de 283 a 679 kg PV ha-1. O uso do herbicida não apresentou efeitos sobre a produção; e a introdução de espécies de estação fria por sobre-semeadura melhorou a produção animal emCN, que possibilitou a colheita de maiores ganhos animal-1 dia-1 e por área.This study evaluated animal production of steers and pasture production of natural grassland and grassland overseeded withItalian ryegrass (Lolium multiflorum, white clover (Trifolium repens and birdsfoot trefoil (Lotus corniculatus, with and without the use of glyphosate herbicide. Treatments consisted of: NG –natural grassland, with annual mowing; ING – natural grassland with overseeding, fertilizing and annual mowing; G1 – Same ING, but with glyphosate application in the first year; G3 – same as G1, with suppression of natural vegetation using herbicide in the second and third years; GF3 – same as G3, with doubled fertilizing in the three

  10. Fotossíntese de biótipos de azevém sob condição de competição Photosynthesis of ryegrass biotypes under different competition levels

    Directory of Open Access Journals (Sweden)

    G. Concenço

    2008-01-01

    Full Text Available As características associadas à atividade fotossintética de biótipos de azevém, resistente e suscetível ao herbicida glyphosate, foram avaliadas sob diferentes níveis de competição entre biótipos. O experimento foi realizado em esquema fatorial 2 x 5, com dois biótipos de azevém, resistente e suscetível ao glyphosate, cultivados em planta única no centro da parcela, competindo com zero, um, dois, três ou quatro plantas do biótipo oposto. Cinqüenta dias após a emergência, foram determinadas a taxa de fluxo de gases pelos estômatos (U - µmol s-1, a concentração de CO2 subestomática (Ci - µmol mol-1 e a taxa fotossintética (A - µmol m-2 s-1, sendo calculado ainda o CO2 consumido (ΔC - µmol mol-1 a partir dos valores de CO2 de referência e CO2 na câmara de avaliação. Os dados foram coletados utilizando-se analisador de gases no infravermelho (IRGA, marca ADC, modelo LCA 4. Foi elaborada matriz de correlação entre as variáveis. Os biótipos de azevém resistente e suscetível ao glyphosate não diferiram quanto à atividade fotossintética na ausência de competição. No entanto, a taxa fotossintética foi reduzida com o aumento na intensidade de competição com plantas do biótipo oposto, tanto para o biótipo resistente como para o suscetível, e também para o biótipo resistente quando em competição com plantas do mesmo biótipo. Atribuiu-se tal comportamento ao aumento no sombreamento mútuo e à competição por luz.Characteristics associated with photosynthetic activity of ryegrass biotypes, susceptible and resistant to glyphosate, were evaluated under different competition levels. The experiment was installed in a factorial design, with two ryegrass biotypes, susceptible and resistant to glyphosate, growing in the plot center, surrounded by 0, 1, 2, 3, and 4 plants of the opposite biotype. Fifty days after emergence, stomatal gas flow rate (U µmol s¹, sub-stomatal CO2 concentration (Ci - µmol mol-1

  11. Bioenergy production from perennial energy crops: a consequential LCA of 12 bioenergy scenarios including land use changes.

    Science.gov (United States)

    Tonini, Davide; Hamelin, Lorie; Wenzel, Henrik; Astrup, Thomas

    2012-12-18

    In the endeavor of optimizing the sustainability of bioenergy production in Denmark, this consequential life cycle assessment (LCA) evaluated the environmental impacts associated with the production of heat and electricity from one hectare of Danish arable land cultivated with three perennial crops: ryegrass (Lolium perenne), willow (Salix viminalis) and Miscanthus giganteus. For each, four conversion pathways were assessed against a fossil fuel reference: (I) anaerobic co-digestion with manure, (II) gasification, (III) combustion in small-to-medium scale biomass combined heat and power (CHP) plants and IV) co-firing in large scale coal-fired CHP plants. Soil carbon changes, direct and indirect land use changes as well as uncertainty analysis (sensitivity, MonteCarlo) were included in the LCA. Results showed that global warming was the bottleneck impact, where only two scenarios, namely willow and Miscanthus co-firing, allowed for an improvement as compared with the reference (-82 and -45 t CO₂-eq. ha⁻¹, respectively). The indirect land use changes impact was quantified as 310 ± 170 t CO₂-eq. ha⁻¹, representing a paramount average of 41% of the induced greenhouse gas emissions. The uncertainty analysis confirmed the results robustness and highlighted the indirect land use changes uncertainty as the only uncertainty that can significantly change the outcome of the LCA results.

  12. [Physical and chemical methods for eliminating propagules of indigenous mycorrhizal fungi from soil samples].

    Science.gov (United States)

    Covacevich, Fernanda; Castellari, Claudia C; Echeverría, Hernán E

    2014-01-01

    The objective of this work was to evaluate methods to eliminate or reduce the number of indigenous arbuscular mycorrhizal fungi (AMF) from soil samples without affecting their edaphic or microbiological properties. At an early trial we evaluated moist heat (autoclaving), dry heat (oven), sodium hypochlorite (NaClO) and formaldehyde at a range of 100.0-3.3μl/g and 16.7-3.3μl/g respectively. There was no germination in plants of ryegrass (Lolium multiflorum Lam.) sown on substrates receiving NaClO (100.0-33.3μl/g), whereas autoclaving significantly increased the available soil phosphorous content. Both treatments failed to eradicate AMF colonization at 9 weeks; therefore, they were discarded. In a second trial, oven and formaldehyde (10.0μl/g) treatments were analyzed to assess the effects of seed decontamination and AMF reinoculation. Both procedures were effective in reducing or eliminating indigenous AMF at a range of soil P availability of 12-29mg/kg. However, the time between soil treatment and AMF multiplication and safety requirements were greater in the case of formaldehyde application. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

  13. Biology of Anicla infecta (Ochsenheimer, 1816 (Lepidoptera, Noctuidae, Noctuinae, under laboratory conditions

    Directory of Open Access Journals (Sweden)

    J. A. TESTON

    Full Text Available Larvae of Anicla infecta (Ochsenheimer, 1816 (Noctuidae feed upon many grasses and may be harmful to cereals and fodder of economic importance. This study was developed aiming to contribute to knowledge of the biology of this species. The rearing was done in an environmental chamber with the following settings: temperature of 25 ± 1ºC; relative humidity of 70% ± 10%, and photoperiod of L14: D10. The larvae fed on ryegrass, Lolium multiflorum Lam. The results express the mean and standard error for the length of every stage in days. For each stage we observed the following time of development: egg 3.2 ± 0.09; larvae 18.7 ± 0.07; pre-pupae 3.3 ± 0.04; pupae 12.6 ± 0.14; and adult longevity was 12.1 ± 1.03. Also the pre-egg-laying period was 4.4 ± 0.59; the egg-laying period was 8.1 ± 0.84; and the post-egg-laying period was 0.3 ± 0.14. The mean number of egg-laying cycles per female was 6.7 ± 0.73; that of eggs per cycle was 77.5 ± 4.37; and total eggs per female was 521.4 ± 47.36.

  14. A novel substance with allelopathic activity in Ginkgo biloba.

    Science.gov (United States)

    Kato-Noguchi, Hisashi; Takeshita, Sayaka; Kimura, Fukiko; Ohno, Osamu; Suenaga, Kiyotake

    2013-12-15

    Ginkgo (Ginkgo biloba) is one of the oldest living tree species and has been widely used in traditional medicine. Leaf extracts of ginkgo, such as the standardized extract EGb761, have become one of the best-selling herbal products. However, no bioactive compound directed at plants has been reported in this species. Therefore, we investigated possible allelopathic activity and searched for allelopathically active substances in ginkgo leaves. An aqueous methanol leaf extract inhibited the growth of roots and shoots of garden cress (Lepidium sativum), lettuce (Lactuca sativa), timothy (Phleum pratense) and ryegrass (Lolium multiflorum) seedlings. The extract was purified by several chromatographic runs and an allelopathically active substance was isolated and identified by spectral analysis to be the novel compound 2-hydroxy-6-(10-hydroxypentadec-11-enyl)benzoic acid. The compound inhibited root and shoot growth of garden cress and timothy at concentrations greater than 3 μM. The activity of the compound was 10- to 52-fold that of nonanoic acid. These results suggest that 2-hydroxy-6-(10-hydroxypentadec-11-enyl)benzoic acid may contribute to the allelopathic effect caused by ginkgo leaf extract. The compound may also have potential as a template for the development of new plant control substances. Copyright © 2013 Elsevier GmbH. All rights reserved.

  15. Polymer Coated Urea in Turfgrass Maintains Vigor and Mitigates Nitrogen's Environmental Impacts.

    Directory of Open Access Journals (Sweden)

    Joshua J LeMonte

    Full Text Available Polymer coated urea (PCU is a N fertilizer which, when added to moist soil, uses temperature-controlled diffusion to regulate N release in matching plant demand and mitigate environmental losses. Uncoated urea and PCU were compared for their effects on gaseous (N2O and NH3 and aqueous (NO3(- N environmental losses in cool season turfgrass over the entire PCU N-release period. Field studies were conducted on established turfgrass sites with mixtures of Kentucky bluegrass (Poa pratensis L. and perennial ryegrass (Lolium perenne L. in sand and loam soils. Each study compared 0 kg N ha(-1 (control to 200 kg N ha(-1 applied as either urea or PCU (Duration 45CR®. Application of urea resulted in 127-476% more evolution of measured N2O into the atmosphere, whereas PCU was similar to background emission levels from the control. Compared to urea, PCU reduced NH3 emissions by 41-49% and N2O emissions by 45-73%, while improving growth and verdure compared to the control. Differences in leachate NO3(- among urea, PCU and control were inconclusive. This improvement in N management to ameliorate atmospheric losses of N using PCU will contribute to conserving natural resources and mitigating environmental impacts of N fertilization in turfgrass.

  16. Genomic and metabolic characterisation of alkaloid biosynthesis by asexual Epichloë fungal endophytes of tall fescue pasture grasses.

    Science.gov (United States)

    Ekanayake, Piyumi N; Kaur, Jatinder; Tian, Pei; Rochfort, Simone J; Guthridge, Kathryn M; Sawbridge, Timothy I; Spangenberg, German C; Forster, John W

    2017-06-01

    Symbiotic associations between tall fescue grasses and asexual Epichloë