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Sample records for blackgrass alopecurus myosuroides

  1. Development of herbicide resistance in black-grass (Alopecurus myosuroides in Bavaria

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    Gehring, Klaus

    2016-02-01

    Full Text Available Black-grass (Alopecurus myosuroides is one of the most important grass weeds in Bavaria. Chemical weed control with high efficacy is very important in crops like winter cereals, oilseed rape and maize. Crop rotations with more winter cereals, reduced soil cultivation and e.g. contract harvesting enhanced distribution of blackgrass in arable farming regions. Effects of herbicide resistance were observed since the last 20 years. The blackgrass herbicide resistance is well observed by the official plant protection service of Bavaria. A wide experience of resistance tests shows the development of resistant black-grass and provides an opportunity for future prospects in resistance dynamics.

  2. Ecological review of black-grass (Alopecurus myosuroides Huds. propagation abilities in relationship with herbicide resistance

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    Maréchal, PY.

    2012-01-01

    Full Text Available Alopecurus myosuroides Huds. (black-grass has always been a major concern for cereal growers, and the development of herbicide resistance does not improve the situation. This review article summarizes the different traits involved in the dispersal pattern of herbicide resistant black-grass individuals within a susceptible field population. Therefore, the whole life cycle of black-grass is depicted from the seed to the seed. From the early vegetative development to the seed falling, every stage is described, taking into account how herbicide resistance can influence or exert a different impact compared to susceptible plants.

  3. Impact of non-target-site-resistance on herbicidal activity of imazamox on blackgrass (Alopecurus myosuroides Huds. in comparison to other ALS-graminicides

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    Sievernich, Bernd

    2014-02-01

    Full Text Available A black-grass (Alopecurus myosuroides Huds. resistance-monitoring conducted by BASF in 2010 - 2012 revealed a high number of accessions with resistance against imazamox. However, application of imazamoxbased products in a winter crop was limited to winter beans in France and United Kingdom only until the introduction of the Clearfield®-production system in autumn 2012 in winter oilseed rape. It is therefore assumed that the resistance mechanisms were probably selected by the frequent use of ACCase- and ALSinhibitors in winter crop rotations during the last 2 decades. Resistance level for each product-biotype combination was calculated according the “R”-classification system (S, R?, RR, RRR by directly comparing the product performance on a biotype versus untreated control. Majority of resistant biotypes did not show a target-site mutation at the known codon Pro197 or Trp574. In order to better evaluate the impact of Non-Target-Site-Resistance (NTSR on the activity of BEYOND (imazamox, ATLANTIS WG (mesosulfuron+iodosulfuron and ABAK (pyroxsulam, biotypes who have shown an ALS-target-site mutation were removed from further analysis. At the dose rate of 35 g ai/ha BEYOND provided good activity on susceptible biotypes of black-grass almost matching up with ATLANTIS WG and ABAK. However, activity of BEYOND declined stronger on biotypes classified as R? or RR for that product, while ATLANTIS WG and ABAK hardly showed any decline in control on this group of biotypes when applied at the recommended dose rate. It is assumed that the underlying NTSR-mechanism is not effective enough yet to confer resistance to ATLANTIS WG and ABAK, but on BEYOND. In contrast, biotypes classified as R? for ATLANTIS WG did show a stronger impact on the activity of BEYOND and ABAK then of ATLANTIS WG. These differences in control level probably do translate into differences in selection pressure as well.

  4. Spread and control of blackgrass (Alopecurus myosuroides according to an increasing occurrence of resistance - Evaluation of field trials in the federal states Brandenburg, Hessen, Saxony, Saxony-Anhalt and Thuringia in the years 2000 - 2014

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    Meinlschmidt, Ewa

    2016-02-01

    Full Text Available An increasing occurrence of blackgrass (Alopecurus myosuroides with high densities has been reported for Brandenburg, Hessen, Saxony-Anhalt, Saxony and Thuringia. In recent years, an increasing resistance to blackgrass especially to ALS inhibitors and partially to ACCase inhibitors has been reported for some eastern federal states and Hessen, too. It was determined to what extent dicotyledonous weeds are associated with blackgrass. The efficacy of different herbicide applications was tested in field trials between 2000 and 2014. A total of 191 trials have been included in the analysis of blackgrass. Using the HRAC-classification of herbicides tested, combinations of herbicides were used which might contribute to solve problems specifically linked to the detected resistance situation of the site. The study aimed to identify the right timing of the herbicide applications as well as applications as single or serial treatments and the use of herbicide at reduced doses according to the intensity of blackgrass. In autumn, single applications of soil active herbicides were not effective enough, especially at a high density of more than 500 heads of blackgrass per m2. The mixtures of soil active herbicides with leave active herbicides applied in autumn achieved very good control. The herbicide sequences were more effective than single applications. In order to counteract further spread of herbicide resistance, the right choice of the mode of action and highly efficacious herbicide treatments are the methods of choice, of course in addition to nonchemical controlling measures such as delayed autumn drilling, ploughing and crop rotation.

  5. Impact of weed control strategies on resistance evolution in Alopecurus myosuroides – a long-term field trial

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    Ulber, Lena

    2016-02-01

    Full Text Available The impact of various herbicide strategies on populations of Alopecurus myosuroides is investigated in a longterm field trial situated in Wendhausen (Germany since 2009. In the initial years of the field experiment, resistant populations were selected by means of repeated application of the same herbicide active ingredients. For the selection of different resistance profiles, herbicides with actives from different HRAC groups were used. The herbicide actives flupyrsulfuron, isoproturon und fenoxaprop-P were applied for two years on large plots. In a succeeding field trial starting in 2011, it was investigated if the now existing resistant field populations could be controlled by various herbicide strategies. Eight different strategies consisting of various herbicide combinations were tested. Resistance evolution was investigated by means of plant counts and molecular genetic analysis.

  6. DNA analysis of herbarium Specimens of the grass weed Alopecurus myosuroides reveals herbicide resistance pre-dated herbicides.

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    Délye, Christophe; Deulvot, Chrystel; Chauvel, Bruno

    2013-01-01

    Acetyl-CoA carboxylase (ACCase) alleles carrying one point mutation that confers resistance to herbicides have been identified in arable grass weed populations where resistance has evolved under the selective pressure of herbicides. In an effort to determine whether herbicide resistance evolves from newly arisen mutations or from standing genetic variation in weed populations, we used herbarium specimens of the grass weed Alopecurus myosuroides to seek mutant ACCase alleles carrying an isoleucine-to-leucine substitution at codon 1781 that endows herbicide resistance. These specimens had been collected between 1788 and 1975, i.e., prior to the commercial release of herbicides inhibiting ACCase. Among the 734 specimens investigated, 685 yielded DNA suitable for PCR. Genotyping the ACCase locus using the derived Cleaved Amplified Polymorphic Sequence (dCAPS) technique identified one heterozygous mutant specimen that had been collected in 1888. Occurrence of a mutant codon encoding a leucine residue at codon 1781 at the heterozygous state was confirmed in this specimen by sequencing, clearly demonstrating that resistance to herbicides can pre-date herbicides in weeds. We conclude that point mutations endowing resistance to herbicides without having associated deleterious pleiotropic effects can be present in weed populations as part of their standing genetic variation, in frequencies higher than the mutation frequency, thereby facilitating their subsequent selection by herbicide applications.

  7. Wheat root length and not branching is altered in the presence of neighbours, including blackgrass.

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    Jessica A Finch

    Full Text Available The effect of neighbouring plants on crop root system architecture may directly interfere with water and nutrient acquisition, yet this important and interesting aspect of competition remains poorly understood. Here, the effect of the weed blackgrass (Alopecurus myosuroides Huds. on wheat (Triticum aestivum L. roots was tested, since a low density of this species (25 plants m-2 can lead to a 10% decrease in wheat yield and herbicide resistance is problematic. We used a simplified growth system based on gelled medium, to grow wheat alongside a neighbour, either another wheat plant, a blackgrass or Brachypodium dystachion individual (a model grass. A detailed analysis of wheat seminal root system architecture showed that the presence of a neighbour principally affected the root length, rather than number or diameter under a high nutrient regime. In particular, the length of first order lateral roots decreased significantly in the presence of blackgrass and Brachypodium. However, this effect was not noted when wheat plants were grown in low nutrient conditions. This suggests that wheat may be less sensitive to the presence of blackgrass when grown in low nutrient conditions. In addition, nutrient availability to the neighbour did not modulate the neighbour effect on wheat root architecture.

  8. Wheat root length and not branching is altered in the presence of neighbours, including blackgrass

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    Finch, Jessica A.; Guillaume, Gaëtan; French, Stephanie A.; Colaço, Renato D. D. R.; Davies, Julia M.

    2017-01-01

    The effect of neighbouring plants on crop root system architecture may directly interfere with water and nutrient acquisition, yet this important and interesting aspect of competition remains poorly understood. Here, the effect of the weed blackgrass (Alopecurus myosuroides Huds.) on wheat (Triticum aestivum L.) roots was tested, since a low density of this species (25 plants m-2) can lead to a 10% decrease in wheat yield and herbicide resistance is problematic. We used a simplified growth system based on gelled medium, to grow wheat alongside a neighbour, either another wheat plant, a blackgrass or Brachypodium dystachion individual (a model grass). A detailed analysis of wheat seminal root system architecture showed that the presence of a neighbour principally affected the root length, rather than number or diameter under a high nutrient regime. In particular, the length of first order lateral roots decreased significantly in the presence of blackgrass and Brachypodium. However, this effect was not noted when wheat plants were grown in low nutrient conditions. This suggests that wheat may be less sensitive to the presence of blackgrass when grown in low nutrient conditions. In addition, nutrient availability to the neighbour did not modulate the neighbour effect on wheat root architecture. PMID:28542446

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

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    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.

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

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    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.

  11. Transcriptome Profiling to Identify Genes Involved in Mesosulfuron-Methyl Resistance in Alopecurus aequalis

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    Ning Zhao

    2017-08-01

    Full Text Available Non-target-site resistance (NTSR to herbicides is a worldwide concern for weed control. However, as the dominant NTSR mechanism in weeds, metabolic resistance is not yet well-characterized at the genetic level. For this study, we have identified a shortawn foxtail (Alopecurus aequalis Sobol. population displaying both TSR and NTSR to mesosulfuron-methyl and fenoxaprop-P-ethyl, yet the molecular basis for this NTSR remains unclear. To investigate the mechanisms of metabolic resistance, an RNA-Seq transcriptome analysis was used to find candidate genes that may confer metabolic resistance to the herbicide mesosulfuron-methyl in this plant population. The RNA-Seq libraries generated 831,846,736 clean reads. The de novo transcriptome assembly yielded 95,479 unigenes (averaging 944 bp in length that were assigned putative annotations. Among these, a total of 29,889 unigenes were assigned to 67 GO terms that contained three main categories, and 14,246 unigenes assigned to 32 predicted KEGG metabolic pathways. Global gene expression was measured using the reads generated from the untreated control (CK, water-only control (WCK, and mesosulfuron-methyl treatment (T of R and susceptible (S. Contigs that showed expression differences between mesosulfuron-methyl-treated R and S biotypes, and between mesosulfuron-methyl-treated, water-treated and untreated R plants were selected for further quantitative real-time PCR (qRT-PCR validation analyses. Seventeen contigs were consistently highly expressed in the resistant A. aequalis plants, including four cytochrome P450 monooxygenase (CytP450 genes, two glutathione S-transferase (GST genes, two glucosyltransferase (GT genes, two ATP-binding cassette (ABC transporter genes, and seven additional contigs with functional annotations related to oxidation, hydrolysis, and plant stress physiology. These 17 contigs could serve as major candidate genes for contributing to metabolic mesosulfuron-methyl resistance; hence

  12. Distribution of endophytic bacteria in Alopecurus aequalis Sobol and Oxalis corniculata L. from soils contaminated by polycyclic aromatic hydrocarbons.

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    Anping Peng

    Full Text Available The distributions of endophytic bacteria in Alopecurus aequalis Sobol and Oxalis corniculata L. grown in soils contaminated with different levels of polycyclic aromatic hydrocarbons (PAHs were investigated with polymerase chain reaction followed by denaturing gradient gel electrophoresis technology (PCR-DGGE and cultivation methods. Twelve types of PAHs, at concentrations varying from 0.16 to 180 mg·kg(-1, were observed in the roots and shoots of the two plants. The total PAH concentrations in Alopecurus aequalis Sobol obtained from three different PAH-contaminated stations were 184, 197, and 304 mg·kg(-1, and the total PAH concentrations in Oxalis corniculata L. were 251, 346, and 600 mg·kg(-1, respectively. The PCR-DGGE results showed that the endophytic bacterial communities in the roots and shoots of the two plants were quite different, although most bacteria belonged to Firmicutes, Proteobacteria, Actinobacteria and Bacteroidetes. A total of 68 endophytic bacterial strains were isolated from different tissues of the two plants and classified into three phyla: Firmicutes, Proteobacteria and Bacteroidetes. In both plants, Bacillus spp. and Pseudomonas spp. were the dominant cultivable populations. With an increase in the PAH pollution level, the diversity and distribution of endophytic bacteria in the two plants changed correspondingly, and the number of cultivable endophytic bacterial strains decreased rapidly. Testing of the isolated endophytic bacteria for tolerance to each type of PAH showed that most isolates could grow well on Luria-Bertani media in the presence of different PAHs, and some isolates were able to grow rapidly on a mineral salt medium with a single PAH as the sole carbon and energy source, indicating that these strains may have the potential to degrade PAHs in plants. This research provides the first insight into the characteristics of endophytic bacterial populations under different PAH pollution levels and provides a

  13. ISOTHECIUM MYOSUROIDES AND THUIDIUM TAMARISCINUM MOSSES AS BIOINDICATORS OF NITROGEN AND HEAVY METAL DEPOSITION IN ATLANTIC OAK WOODLANDS

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    K. Wilkins

    2015-04-01

    Full Text Available Moss tissue chemistry is widely used as a bioindicator of atmospheric deposition. The objective of this study was to compare the tissue chemistry of two moss species in Irish Atlantic oak woodlands, Isothecium myosuroides [Im] and Thuidium tamariscinum [Tt], and to determine their relationship to indices of atmospheric deposition. Moss species were collected from twenty-two woodland sites during April 2013 and analysed for nitrogen, sulphur, and eleven heavy metals. Nitrogen content was significantly correlated between species (rs = 0.84, but their mean values (Im = 1.23%, Tt = 1.34% were significantly different. A simple linear regression suggested that nitrogen content was significantly related to atmospheric ammonia (R2 = 0.67 [Im], R2 = 0.65 [Tt] and total nitrogen deposition (R2 = 0.57 [Im], R2 = 0.54 [Tt]. Many heavy metals had significant interspecies correlations (Al, V, Ni, Cu, Zn, As, Sb, Pb; rs = 0.46−0.77. A few metals (As, Sb and Pb were positively correlated with easting and northing for both species, which may suggest transboundary or national industrial emissions sources. The results suggest that both species could be used as bioindicators of deposition for nitrogen and some heavy metals, although further study of the relationship between tissue concentrations and atmospheric deposition is warranted. Furthermore, interspecies calibration is required to use both species in conjunction.

  14. Isparta Yöresinde Doğal Yayılış Gösteren Bazı Bitki Türlerinin Kesme ve Kuru Çiçekçilikte Kullanım Olanakları

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    Güliz TÜRKMENOĞLU

    2016-04-01

    Full Text Available Bu çalışmada Isparta yöresinde yayılış gösteren bazı doğal bitki taksonlarının kesme ve kuru çiçekçilikte kullanım olanakları araştırılmıştır. 2014-2015 yılları arasında gerçekleştirilen arazi çalışmalarında Acantholimon acerosum subsp. acerosum var. acerosum, Origanum sipyleum, Hypericum perforatum, Fibigia clypeata subsp. clypeata var. eriocarpa, Minuartia gracilis, Dianthus calocephalus,  Alyssum murale subsp. murale var. murale, Dactylis glomerata subsp. hispanica, Alopecurus myosuroides subsp. myosuroides, Iris pseudacorus bitki taksonları toplanmıştır. O. sipyleum ve M. gracilis ülkemiz için endemik türlerdir ve IUCN Red Data Book tehlike kategorilerine göre az tehdit altında, en az endişe verici (LR(Ic ve zarar görebilir (VU  grubuna girmektedir. Toplanan bitki taksonlarının morfolojik özelliklerden bitki boyu, çiçek sayısı, çiçeklenme ve yapraklanma başlangıcı ölçümleri yapılmıştır. Yapılan ölçümlerde bitki boyu en uzun olan takson 163 cm ile Iris pseudacorus, en kısa olan takson 10 cm ile Minuartıa gracilis’tir. Çiçek sayısı en fazla olan takson 54 adet ile Alopecurus myosuroides subsp. myosuroides, en az olan takson ise 1 adet ile Dactylis glomerata subsp. hispanica’dır. Tespit edilen bu türlerin çiçek renkleri turuncu ve sarı ağırlıklıdır. Çiçeklenme süresi genellikle Nisan-Ağustos ayları arasındadır.

  15. Impact of fungicides on weed growth

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    Nordmeyer, Henning

    2014-02-01

    Full Text Available The study has shown that fungicides influence the growth of weeds. The competition against crops will be substantially reduced. Bioassays in a climate chamber variation in temperature as well as different lightning phases and microplot trials under semi field levels were carried out to investigate the influence of fungicides on weed growth. Selected weed species (Alopecurus myosuroides, Viola arvensis, Galium aparine, Stellaria media, Lamium purpureum have been examined with different dose rates of fungicides (Adexar, Bravo 500, Diamant, Crupozin flüssig. Weed species showed a different sensitivity. There were leaf discoloration, contractions and growth inhibition. In some cases using common practise dose rates of fungicides more than 70% growth inhibition could be estimated 14 days after application in comparison to the untreated control. Effects were much stronger in bioassays than in semi field trials.

  16. New xenophytes from Gran Canaria (Canary Islands, Spain, with emphasis on naturalized and (potentially invasive species

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    Verloove, F.

    2013-12-01

    Full Text Available Trabajos recientes de campo en Gran Canaria han facilitado el descubrimiento de nuevas localidades para plantas vasculares no nativas. Agave attenuata, Antigonon leptopus, Atriplex nummularia, Cascabela thevetia, Cenchrus echinatus, Cuscuta campestris, Diplachne fusca subsp. uninervia, Diplotaxis tenuifolia, Dysphania anthelmintica (hasta ahora confundida con D. ambrosioides, Eclipta prostrata, Euphorbia pulcherrima, Fagopyrum esculentum, Gossypium barbadense, Lablab purpureus, Lemna minuta, Opuntia leucotricha, Passiflora edulis, Pennisetum glaucum, Phaseolus acutifolius, Pluchea carolinensis, Prosopis juliflora, Salvia microphylla, Schinus terebinthifolius, Senna spectabilis, Solanum chrysotrichum, Tecoma stans, Tipuana tipu, Urochloa mutica, U. plantaginea y Washingtonia se citan por primera vez para las Islas Canarias, mientras que Alopecurus myosuroides, Amaranthus blitoides, Bothriochloa ischaemum var. songarica, Cardamine flexuosa subsp. debilis, Heliotropium curassavicum, Leonotis nepetifolia, Medicago lupulina, Parkinsonia aculeata, Physalis peruviana, Phytolacca americana y Turnera ulmifolia son nuevas para la flora de la isla de Gran Canaria. Finalmente, se confirma la presencia de Paspalum vaginatum, P. distichum y Cortaderia selloana en Gran Canaria.Trabajos recientes de campo en Gran Canaria han facilitado el descubrimiento de nuevas localidades para plantas vasculares no nativas. Agave attenuata, Antigonon leptopus, Atriplex nummularia, Cascabela thevetia, Cenchrus echinatus, Cuscuta campestris, Diplachne fusca subsp. uninervia, Diplotaxis tenuifolia, Dysphania anthelmintica (hasta ahora confundida con D. ambrosioides, Eclipta prostrata, Euphorbia pulcherrima, Fagopyrum esculentum, Gossypium barbadense, Lablab purpureus, Lemna minuta, Opuntia leucotricha, Passiflora edulis, Pennisetum glaucum, Phaseolus acutifolius, Pluchea carolinensis, Prosopis juliflora, Salvia microphylla, Schinus terebinthifolius, Senna spectabilis, Solanum

  17. Diversité des communautés de mauvaises herbes des cultures annuelles de Côte-d'Or (France

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    Dessaint F.

    2001-01-01

    Full Text Available Diversity of weed communities of annual crops in Cote-d'Or, France. Weed flora of annual crops in Cote-d'Or, France, were characterized in three successive growing seasons by measuring species frequencies and abundance over 245 fields. A total of 210 species in 143 genera were recorded representing a total of 43 families with Asteraceae, Poaceae, Fabaceae, Scrophulariaceae, Brassicaceae, Lamiaceae and Caryophyllaceae predominating. More than half of the species occurred in less than 5/ of the sampled plots (fields x years and only 9 species (namely Galium aparine L., Polygonum aviculare L., Fallopia convolvulus (L. A. Loeve, Alopecurus myosuroides Hudson, Stellaria media (L. Vill., Convolvulus arvensis L., Sinapis arvensis L., Veronica persica Poiret and Anagallis arvensis L. occurred in more than 50/ of the plots. The maximum plot density was greater than 20 plants per square metre for more than one third of the species. Meanwhile, the plots where the density exceeded 20 plants per square metre, were rare and represented, for the most abundant species (A. myosuroides, less than 16/ of the plots. The total number of weed species per plots varied from 4 to 65 with a median species number of 20. In most of the plots, the weed community was mainly composed of species having a small density (less than one plant per square metre and was dominated by only one or two species in half of the plots.

  18. Determination of ploidy level and isolation of genes encoding acetyl-CoA carboxylase in Japanese Foxtail (Alopecurus japonicus.

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    Hongle Xu

    Full Text Available Ploidy level is important in biodiversity studies and in developing strategies for isolating important plant genes. Many herbicide-resistant weed species are polyploids, but our understanding of these polyploid weeds is limited. Japanese foxtail, a noxious agricultural grass weed, has evolved herbicide resistance. However, most studies on this weed have ignored the fact that there are multiple copies of target genes. This may complicate the study of resistance mechanisms. Japanese foxtail was found to be a tetraploid by flow cytometer and chromosome counting, two commonly used methods in the determination of ploidy levels. We found that there are two copies of the gene encoding plastidic acetyl-CoA carboxylase (ACCase in Japanese foxtail and all the homologous genes are expressed. Additionally, no difference in ploidy levels or ACCase gene copy numbers was observed between an ACCase-inhibiting herbicide-resistant and a herbicide-sensitive population in this study.

  19. Studying Geographical Distribution Map of Weeds of Irrigated Wheat Fields of Ardabil Province

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    B Soheili

    2013-12-01

    Full Text Available In order to identify the density and abundance of weeds in irrigated wheat fields of Ardabil Province, 76 samples of irrigated wheat fields based on cultivation area from all counties of Ardabil province for six years (2001-2006 were selected. The genus and species of weeds from each sampling fields and their population indices density, frequency and uniformity of each species were calculated by using Thomas method. Geographic coordinates of field (Latitude, Altitude and Elevation were the main coverage and were determined by using GPS. These data were used for producing weed maps using GIS in irrigated wheat fields of Ardabil province. Results showed that bedstraw (Galium tricurnatum, Fumitory(Fumaria vaillantiand wildradish (Raphanus raphanistrum were dominant broad leaf weed species and wild oats (Avena fatua, rye (Secale cereal and mouse foxtail(Alopecurus myosuroides dominant grassy weeds species in irrigated wheat fields of Ardabil province. Bindweed (Convolvulus arvensis, Canada thistle(Cirsium arvenseand Acroptilon repens were the most important disturbing plants prior to harvesting in irrigated wheat fields of Ardabil province.

  20. Development and characterization of mutant winter wheat (Triticum aestivum L.) accessions resistant to the herbicide quizalofop.

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    Ostlie, Michael; Haley, Scott D; Anderson, Victoria; Shaner, Dale; Manmathan, Harish; Beil, Craig; Westra, Phillip

    2015-02-01

    New herbicide resistance traits in wheat were produced through the use of induced mutagenesis. While herbicide-resistant crops have become common in many agricultural systems, wheat has seen few introductions of herbicide resistance traits. A population of Hatcher winter wheat treated with ethyl methanesulfonate was screened with quizalofop to identify herbicide-resistant plants. Initial testing identified plants that survived multiple quizalofop applications. A series of experiments were designed to characterize this trait. In greenhouse studies the mutants exhibited high levels of quizalofop resistance compared to non-mutant wheat. Sequencing ACC1 revealed a novel missense mutation causing an alanine to valine change at position 2004 (Alopecurus myosuroides reference sequence). Plants carrying single mutations in wheat's three genomes (A, B, D) were identified. Acetyl co-enzyme A carboxylase in resistant plants was 4- to 10-fold more tolerant to quizalofop. Populations of segregating backcross progenies were developed by crossing each of the three individual mutants with wild-type wheat. Experiments conducted with these populations confirmed largely normal segregation, with each mutant allele conferring an additive level of resistance. Further tests showed that the A genome mutation conferred the greatest resistance and the B genome mutation conferred the least resistance to quizalofop. The non-transgenic herbicide resistance trait identified will enhance weed control strategies in wheat.

  1. Estimating economic thresholds for site-specific weed control using manual weed counts and sensor technology: an example based on three winter wheat trials.

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    Keller, Martina; Gutjahr, Christoph; Möhring, Jens; Weis, Martin; Sökefeld, Markus; Gerhards, Roland

    2014-02-01

    Precision experimental design uses the natural heterogeneity of agricultural fields and combines sensor technology with linear mixed models to estimate the effect of weeds, soil properties and herbicide on yield. These estimates can be used to derive economic thresholds. Three field trials are presented using the precision experimental design in winter wheat. Weed densities were determined by manual sampling and bi-spectral cameras, yield and soil properties were mapped. Galium aparine, other broad-leaved weeds and Alopecurus myosuroides reduced yield by 17.5, 1.2 and 12.4 kg ha(-1) plant(-1)  m(2) in one trial. The determined thresholds for site-specific weed control with independently applied herbicides were 4, 48 and 12 plants m(-2), respectively. Spring drought reduced yield effects of weeds considerably in one trial, since water became yield limiting. A negative herbicide effect on the crop was negligible, except in one trial, in which the herbicide mixture tended to reduce yield by 0.6 t ha(-1). Bi-spectral cameras for weed counting were of limited use and still need improvement. Nevertheless, large weed patches were correctly identified. The current paper presents a new approach to conducting field trials and deriving decision rules for weed control in farmers' fields. © 2013 Society of Chemical Industry.

  2. Psárky Alopecurus aequalis a A. geniculatus v České republice: jejich určování a rozšíření

    Czech Academy of Sciences Publication Activity Database

    Bureš, P.; Danihelka, Jiří; Husáková, M.; Pařil, P.

    2008-01-01

    Roč. 23, - (2008), s. 3-61 ISSN 0862-2035 R&D Projects: GA MŠk(CZ) LC06073; GA ČR(CZ) GA206/07/0706 Institutional research plan: CEZ:AV0Z60050516 Keywords : phytogeography * Poaceae * Central Europe Subject RIV: EF - Botanics

  3. Effect of Cover Crops on Vertical Distribution of Leaf Area and Dry Matter of Soybean (Glycine max L. in Competition with Weeds

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    seyyedeh samaneh hashemi

    2017-08-01

    foxtail (Setaria viridis L., foxtail grass (Alopecurus myosuroides Huds, and red root pigweed (Amaranthus retroflexus L. in the experimental field. The other weed was considered as the others. At the soybean canopy closure stage, a vertical card board frame marked in 20-cm increments was used in the field as a guide to cut standing plants including soybean, cover crops and weeds. In each vertical layer of canopy, leaves and stem samples were separated. The leaf area both crops and weeds were measured with a leaf area meter LICOR-3000A (LI-COR, Lincoln, NE, USA. Stem and leaf samples oven dried. Results and discussion The results showed that the maximum leaf area and dry matter of soybean was varied in different layers of canopy depending on the type of cover crop and cover crop planting time, while delaying in planting of cover crop causes lower leaf area and dry matter than the plants were planted at the same time with soybean. In most cases, the maximum leaf area index and dry matter accumulation of weeds were obtained in primary layer (0-20 cm. The maximum weed leaf area (290.4 cm2 was observed in simultaneous planting of soybean with fenugreek and maximum of total weed dry matter (12.4 g.plant-1 was observed in soybean without weeding, while the minimum of weed total leaf area and total weed dry matter (0 cm2 and 0 g.plant-1, respectively was achieved in planting of winter vetch after 21 days of soybean planting. Also delayed planting of winter vetch produced the maximum grain yield (3792.6 kg.ha-1 of soybean in weedy plots, where it had the greatest weed suppressive ability than other cover crops. Conclusion Winter vetch can suppress weed with competition and allelopathic mechanism, so we can conclude that winter vetch planting21 days after soybean planting is suitable replacement for weed suppression in sustainable agriculture.

  4. 76 FR 39888 - Endangered Species Recovery Permit Applications

    Science.gov (United States)

    2011-07-07

    ... (Sonoma alopecurus); Amsinckia grandiflora (large-flowered fiddleneck); Arabis mcdonaldiana (McDonald's... of receipt of permit applications; request for comment. SUMMARY: We, the U.S. Fish and Wildlife... received on or before August 8, 2011. ADDRESSES: Written data or comments should be submitted to the U.S...

  5. The influence of mountain meadow management on the occurence of Puccinia perplexans Plow

    Czech Academy of Sciences Publication Activity Database

    Voženílková, B.; Marková, J.; Klimeš, F.; Květ, Jan; Mašková, Z.

    2008-01-01

    Roč. 115, č. 4 (2008), s. 167-171 ISSN 1861-3829 R&D Projects: GA ČR(CZ) GA206/99/1410 Institutional research plan: CEZ:AV0Z60870520 Keywords : Alopecurus pratensis * fallow stand * mown stand * mulched stand * rust fungi Subject RIV: EF - Botanics Impact factor: 0.566, year: 2008

  6. Increasing efficacy of graminicides with a forward angled spray

    DEFF Research Database (Denmark)

    Jensen, Peter Kryger

    2012-01-01

    Control of annual grass species with vertically oriented leaves in agricultural crops by application of foliar acting herbicides with conventional hydraulic sprayers can be increased using forward angled nozzles. Changing the spray angle from the normally predominantly vertical spray towards...... an angled spray increases the potential target size of vertically oriented targets. This theory was tested in field experiments from 2005 to 2009 investigating control of three different grass species and a dicotyledonous weed species at early growth stages using foliar acting herbicides. Lolium perenne...... efficacy on L. perenne at early growth stages using nozzles with different spray quality, at different driving speeds and in different wind conditions. Similarly graminicide efficacy was increased when nozzles were angled 60° forward controlling A. myosuroides. Experiments investigating control of the two...

  7. Weed Growth Stage Estimator Using Deep Convolutional Neural Networks.

    Science.gov (United States)

    Teimouri, Nima; Dyrmann, Mads; Nielsen, Per Rydahl; Mathiassen, Solvejg Kopp; Somerville, Gayle J; Jørgensen, Rasmus Nyholm

    2018-05-16

    This study outlines a new method of automatically estimating weed species and growth stages (from cotyledon until eight leaves are visible) of in situ images covering 18 weed species or families. Images of weeds growing within a variety of crops were gathered across variable environmental conditions with regards to soil types, resolution and light settings. Then, 9649 of these images were used for training the computer, which automatically divided the weeds into nine growth classes. The performance of this proposed convolutional neural network approach was evaluated on a further set of 2516 images, which also varied in term of crop, soil type, image resolution and light conditions. The overall performance of this approach achieved a maximum accuracy of 78% for identifying Polygonum spp. and a minimum accuracy of 46% for blackgrass. In addition, it achieved an average 70% accuracy rate in estimating the number of leaves and 96% accuracy when accepting a deviation of two leaves. These results show that this new method of using deep convolutional neural networks has a relatively high ability to estimate early growth stages across a wide variety of weed species.

  8. REVISIÓN TAXONÓMICA DEL GÉNERO LELLINGERIA (POLYPODIACEAE PARA COLOMBIA

    Directory of Open Access Journals (Sweden)

    Murillo José

    2010-12-01

    Full Text Available Se presenta la revisión taxonómica del género Lellingeria para Colombia, la cualcontiene una clave dicotómica para las especies, descripciones del género y especies,ilustraciones de todas las especies y anotaciones sobre la distribución. El género estáformado por 19 especies de distribución principalmente Andina, aunque cinco deéstas también se encuentran en las regiones Amazónica, Caribe y Pacífi ca. Aunquecrecen desde el nivel del mar hasta los 3750 m de altitud, la mayor diversidad seencuentra entre los 1200 y los 2500 m. Las especies más frecuentes y más ampliamente distribuidas son L. major, L. myosuroides y L. subsessilis. Se describe una especie nueva y se registran por primera vez para el país a L. mitchelliae y L. tenuicula.

  9. Bio-herbicide effect of salt marsh tolerant Enterobacter sp. I-3 on weed seed germination and seedling growth

    International Nuclear Information System (INIS)

    Radhakrishan, R.; Lee, I.J.

    2017-01-01

    Weeds are major challenges in crop cultivation and cause yield loss. The bacteria based bio-herbicides are emerging against chemical herbicides. This study was aimed to explore the bio-herbicide effect of salt marsh tolerant Enterobacter sp. I-3 on various weed species. The efficacy of I-3 bacterial isolates against weed growth was compared with I-4-5 bacterial strain. The bacterial strains, I-3 and I-4-5 inhibited the seed germination of Cyperus microiria Maxim. Enterobacter sp. I-3 showed higher weed control activity than I-4-5. It was confirmed with growth reduction of C. microiria Maxim. The seed germination of Digitaria sanguinalis L. weed was accelerated during the interaction of I-4-5 and it was drastically declined by I-3 bacterial culture. However, Alopecurus aequalis Sobol. seeds treated with either I-3 or I-4-5 bacterial culture showed no significant germination inhibition. The results of this study suggested that salt marsh tolerant Enterobacter sp. I-3 can be applied as bacterial herbicides to control weeds in agricultural fields. (author)

  10. [Plant communities in the terrestrial-aquatic transition zone in the paramo of Chingaza, Colombia].

    Science.gov (United States)

    Schmidt-Mumm, Udo; Vargas Ríos, Orlando

    2012-03-01

    Plant communities in the terrestrial-aquatic transition zone in the paramo of Chingaza, Colombia. High Andean paramo ecosystems are an important water resource for many towns, and major cities in this region. The aquatic and wetland vegetation of different paramo lakes, pond, swamps and bogs was studied according to the classical phytosociological approach, which is based on homogenous stands, but excludes any border phenomena or transitional zone. The present research aimed at determining the aquatic and wetland vegetation along different moisture gradients. A total of 89 species in 30 transects were reported, of which Crassula venezuelensis, Carex honplandii, Callitriche nubigena, Eleocharis macrostachya, Ranunculus flagelliformis, R. nubigenus, Eleocharis stenocarpa, Galium ascendens y Alopecurus aequalis were present in more than one third of the transects. Numerical classification and indicator species analysis resulted in the definition of the next 18 communities: 1) Calamagrostis effusa, 2) Sphagnum cuspidatum, 3) Cyperus rufus, 4) Eleocharis stenocarpa, 5) Carex acutata, 6) Poa annua,7) Valeriana sp., 8) Ranunculus flagelliformis, 9) Carex bonplandii, 10) Festuca andicola. 11) Muhlenbergia fustigiata, 12) Elatine paramoana, 13) Isoëtes palmeri, 14) Crassula venezuelensis, 15) Lilaeopsis macloviana, 16) Callitriche nubigena, 17) Potamogeton paramoanus and 18) Potamogeton illinoensis. The ordination of communities reveals the presence of three different aquatic-terrestrial gradients which are related to the life form structure of species that characterized the various communities. We concluded that patchiness and heterogeneity of the vegetation is mainly the result of alterations caused by human activities (burning, cattle raise and material extraction for road and dam construction).

  11. Metals and arsenic in soils and corresponding vegetation at Central Elbe river floodplains (Germany)

    Energy Technology Data Exchange (ETDEWEB)

    Overesch, M. [Department for Geo- and Agroecology, Institute of Spatial Analysis and Planning in Areas of Intensive Agriculture, University of Vechta, P.O. Box 1553, D-49364 Vechta (Germany)]. E-mail: moveresch@ispa.uni-vechta.de; Rinklebe, J. [Department of Soil Science, UFZ Center for Environmental Research Leipzig-Halle, Theodor-Lieser-Strasse 4, D-06120 Halle (Germany)]. E-mail: joerg.rinklebe@ufz.de; Broll, G. [Department for Geo- and Agroecology, Institute of Spatial Analysis and Planning in Areas of Intensive Agriculture, University of Vechta, P.O. Box 1553, D-49364 Vechta (Germany)]. E-mail: gbroll@ispa.uni-vechta.de; Neue, H.-U. [Department of Soil Science, UFZ Center for Environmental Research Leipzig-Halle, Theodor-Lieser-Strasse 4, D-06120 Halle (Germany)]. E-mail: heinz-ulrich.neue@ufz.de

    2007-02-15

    Floodplain soils at the Elbe river are frequently polluted with metals and arsenic. High contents of these pollutants were detected down to subsoil layers. NH{sub 4}NO{sub 3}-extractable (phytoavailable) Cd, Ni, and Zn were elevated in horizons with high acidity. Among five common floodplain plant species, Artemisia vulgaris showed highest concentrations of Cd, Cu, and Hg, Alopecurus pratensis of As and Phalaris arundinacea of Ni, Pb, and Zn. Relationships were weak between metal concentrations in plants and phytoavailable stocks in soil. As and Hg uptake seems to be enhanced on long submerged soils. Enrichments of Cd and Hg are linked to a special plant community composition. Grassland herbage sampled in July/August revealed higher concentrations of As (+122%), Hg (+124%), and Pb (+3723%) than in May. To limit harmful transfers into the food chain, low-lying terraces and flood channels revealing highest contaminations or phytoavailabilities should be excluded from mowing and grazing. - Soils in the Elbe river floodplains are highly polluted with metals and arsenic and a critical enrichment in the grassland herbage seems to be most likely in flood channels or within special plant species.

  12. Arbuscular mycorrhizas are present on Spitsbergen.

    Science.gov (United States)

    Newsham, K K; Eidesen, P B; Davey, M L; Axelsen, J; Courtecuisse, E; Flintrop, C; Johansson, A G; Kiepert, M; Larsen, S E; Lorberau, K E; Maurset, M; McQuilkin, J; Misiak, M; Pop, A; Thompson, S; Read, D J

    2017-10-01

    A previous study of 76 plant species on Spitsbergen in the High Arctic concluded that structures resembling arbuscular mycorrhizas were absent from roots. Here, we report a survey examining the roots of 13 grass and forb species collected from 12 sites on the island for arbuscular mycorrhizal (AM) colonisation. Of the 102 individuals collected, we recorded AM endophytes in the roots of 41 plants of 11 species (Alopecurus ovatus, Deschampsia alpina, Festuca rubra ssp. richardsonii, putative viviparous hybrids of Poa arctica and Poa pratensis, Poa arctica ssp. arctica, Trisetum spicatum, Coptidium spitsbergense, Ranunculus nivalis, Ranunculus pygmaeus, Ranunculus sulphureus and Taraxacum arcticum) sampled from 10 sites. Both coarse AM endophyte, with hyphae of 5-10 μm width, vesicles and occasional arbuscules, and fine endophyte, consisting of hyphae of 1-3 μm width and sparse arbuscules, were recorded in roots. Coarse AM hyphae, vesicles, arbuscules and fine endophyte hyphae occupied 1.0-30.7, 0.8-18.3, 0.7-11.9 and 0.7-12.8% of the root lengths of colonised plants, respectively. Principal component analysis indicated no associations between the abundances of AM structures in roots and edaphic factors. We conclude that the AM symbiosis is present in grass and forb roots on Spitsbergen.

  13. Spectrometric analyses in comparison to the physiological condition of heavy metal stressed floodplain vegetation in a standardised experiment

    Science.gov (United States)

    Götze, Christian; Jung, András; Merbach, Ines; Wennrich, Rainer; Gläßer, Cornelia

    2010-06-01

    Floodplain ecosystems are affected by flood dynamics, nutrient supply as well as anthropogenic activities. Heavy metal pollution poses a serious environmental challenge. Pollution transfer from the soil to vegetation is still present at the central location of Elbe River, Germany. The goal of this study was to assess and separate the current heavy metal contamination of the floodplain ecosystem, using spectrometric field and laboratory measurements. A standardized pot experiment with floodplain vegetation in differently contaminated soils provided the basis for the measurements. The dominant plant types of the floodplains are: Urtica dioica, Phalaris arundinacea and Alopecurus pratensis, these were also chemically analysed. Various vegetation indices and methods were used to estimate the red edge position, to normalise the spectral curve of the vegetation and to investigate the potential of different methods for separating plant stress in floodplain vegetation. The main task was to compare spectral bands during phenological phases to find a method to detect heavy metal stress in plants. A multi-level algorithm for the curve parameterisation was developed. Chemo-analytical and ecophysiological parameters of plants were considered in the results and correlated with spectral data. The results of this study show the influence of heavy metals on the spectral characteristics of the focal plants. The developed method (depth CR1730) showed significant relationship between the plants and the contamination.

  14. Temperature and water potential of grey clays in relation to their physical, chemical and microbiological characteristics and phytocoenology within the scope of the Radovesice Dump

    Directory of Open Access Journals (Sweden)

    Lenka Zoubková

    2015-07-01

    Full Text Available Radovesice Dump is a part of brown-coal Most basin, which is situated in the northern part of the Czech Republic. Grey clays are the anthropogenic substrates, which have been used here as a reclamation material in most cases. Water potential of these substrates corresponds to their physical properties, annual precipitation, soil temperature and terrain exposition. All of these characteristics are the limiting factors of soil water, which is available to plants. Area left to spontaneous succession and reclaimed area served as the serviced ones. Water potential was studied in three depths (10, 20 and 30 cm of soil profile and the evaluated values showed significant difference between individual depths as well as exposition. As far as chemical analyses are concerned, the highest values were recorded in case of reclaimed area, whereas the levels of soil moisture here were medium. On the other hand, area left to spontaneous succession showed the lowest values in this sense, however specific representation of vegetation was much large-scale. As far as microbiological characteristics are concerned, the concentrations of phospholipid fatty acids were relatively low in both cases. To the dominant herb species belonged Calamagrostis epigejos, Urtica dioica, Alopecurus pratensis and Astragalus glycyphyllos. It was found that spontaneous succession was more variable as far as the specific representation of vegetation is concerned, though favourable soil physical and chemical properties were provided by technical reclamation too.

  15. 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.

  16. Variations of Leaf Cuticular Waxes Among C3 and C4 Gramineae Herbs.

    Science.gov (United States)

    He, Yuji; Gao, Jianhua; Guo, Na; Guo, Yanjun

    2016-11-01

    Modern C4 plants are commonly distributed in hot and dry environments whereas C3 plants predominate in cool and shade areas. At the outmost of plant surface, the deposition and chemical composition of cuticular waxes vary under different environmental conditions. However, whether such variation of cuticular wax is related to the distribution of C3 and C4 under different environmental conditions is still not clear. In this study, leaves of six C3 Gramineae herbs distributed in spring, Roegneria kamoji, Polypogon fugax, Poa annua, Avena fatua, Alopecurus aequalis, and Oplismenus undulatifolius, and four C4 and one C3 Gramineae herbs distributed in summer, Digitaria sanguinalis, Eleusine indica, Setaria viridis, S. plicata, and O. undulatifolius, were sampled and analyzed for cuticular wax. Plates were the main epicuticular wax morphology in both C3 and C4 plants except S. plicata. The plates melted in C4 plants but not in C3 plants. The total cuticular wax amounts in C4 plants were significantly lower than those in C3 plants, except for O. undulatifolius. Primary alcohols were the most abundant compounds in C3 plants, whereas n-alkanes were relatively the most abundant compounds in C4 plants. C 29 was the most abundant n-alkane in C3 plants except for O. undulatifolius, whereas the most abundant n-alkane was C 31 or C 33 in C4 plants. The average chain length (ACL) of n-alkanes was higher in C4 than in C3 plants, whereas the ACL of n-alkanoic acids was higher in C3 than C4 plants. The cluster analysis based on the distribution of n-alkanes clearly distinguished C3 and C4 plants into two groups, except for O. undulatifolius which was grouped with C4 plants. These results suggest that the variations of cuticular waxes among C3 and C4 Gramineae herbs are related to the distribution of C3 and C4 plants under different environmental conditions. © 2016 Wiley-VHCA AG, Zurich, Switzerland.

  17. Comunidades vegetales de las transiciones terrestre-acuáticas del páramo de Chingaza, Colombia

    Directory of Open Access Journals (Sweden)

    Udo Schmidt-Mumm

    2012-03-01

    aquatic and wetland vegetation along different moisture gradients. A total of 89 species in 30 transects were reported, of which Crassula venezuelensis, Carex bonplandii, Callitriche nubigena, Eleocharis macrostachya, Ranunculus flagelliformis, R. nubigenus, Eleocharis stenocarpa, Galium ascendens y Alopecurus aequalis were present in more than one third of the transects. Numerical classification and indicator species analysis resulted in the definition of the next 18 communities: 1 Calamagrostis effusa, 2 Sphagnum cuspidatum, 3 Cyperus rufus, 4 Eleocharis stenocarpa, 5 Carex acutata, 6 Poa annua, 7 Valeriana sp., 8 Ranunculus flagelliformis, 9 Carex bonplandii, 10 Festuca andicola, 11 Muhlenbergia fastigiata, 12 Elatine paramoana, 13 Isoëtes palmeri, 14 Crassula venezuelensis, 15 Lilaeopsis macloviana, 16 Callitriche nubigena, 17 Potamogeton paramoanus and 18 Potamogeton illinoensis. The ordination of communities reveals the presence of three different aquatic-terrestrial gradients which are related to the life form structure of species that characterized the various communities. We concluded that patchiness and heterogeneity of the vegetation is mainly the result of alterations caused by human activities (burning, cattle raise and material extraction for road and dam construction.

  18. Analysis of landslide overgrowing rates at Vaskiny Dachi key site, Central Yamal, Russia

    Science.gov (United States)

    Khomutov, A.

    2009-04-01

    An estimation of overgrowing of landslide-affected slopes by vegetation at three main landslide elements: shear surface, landslide body and "frontal zone" at Vaskiny Dachi key site is presented. Vaskiny Dachi key site is located in the watershed of Se-Yakha and Mordy-Yakha rivers on Central Yamal, Russia. The area is represented by highly-dissected alluvial-lacustrine-marine plains and terraces. The closest to Vaskiny Dachi climate station is Marresale, about 90 km southwest of Vaskiny Dachi, at the Kara sea coast. The weather here is probably somewhat cooler than at Vaskiny Dachi. The average annual (summer) air temperature at Marresale is -8.3° C (4.3° C) ("Russia's Weather" Server). To estimate vegetation cover dynamics on cryogenic landslides at "Vaskiny Dachi", data published by O.Rebristaya and others (1995) were used. Their observations were done in 1991-1993, and were supplemented by further field observations (Leibman et al., 2000, Khomutov & Leibman 2007) and by field and remote sensing observations in 2008. An estimation of vegetation cover dynamics on cryogenic landslides at "Vaskiny Dachi" leads to the following results. Immediately after landsliding in 1989, landslide shear surface was bare without any vegetation, landslide body had initial vegetation, and "frontal zone" was under liquefied sediment masses. "Frontal zone" formed in front of a landslide body, appears as a result of damming of drainage routes by a landslide body with flooding of the shear surface "upstream" of the landslide body, formation of a sedge-cottongrass meadow there, and swamping downstream (Khomutov & Leibman 2007). By 1993, landslide shear surface got overgrown by species subordinate in surrounding initial landscapes (Alopecurus alpinus, Festuca ovina, Calamagrostis neglecta, Poa alpigena ssp. Alpigena, etc.). Landslide body was covered by initial communities which got depressed: vitality of Salix polaris, Vaccinium vitis-idaea was reduced, dead off moss cover and overgrown