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Sample records for alfalfa medicago sativa

  1. Alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Fu, Chunxiang; Hernandez, Timothy; Zhou, Chuanen; Wang, Zeng-Yu

    2015-01-01

    Alfalfa (Medicago sativa L.) is a high-quality forage crop widely grown throughout the world. This chapter describes an efficient protocol that allows for the generation of large number of transgenic alfalfa plants by sonication-assisted Agrobacterium-mediated transformation. Binary vectors carrying different selectable marker genes that confer resistance to phosphinothricin (bar), kanamycin (npt II), or hygromycin (hph) were used to generate transgenic alfalfa plants. Intact trifoliates collected from clonally propagated plants in the greenhouse were sterilized with bleach and then inoculated with Agrobacterium strain EHA105. More than 80 % of infected leaf pieces could produce rooted transgenic plants in 4-5 months after Agrobacterium-mediated transformation.

  2. Alfalfa (Medicago Sativa L As A Promising Forage In Indonesia

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    Sajimin

    2011-06-01

    Full Text Available Alfalfa (Medicago sativa L or Lucerne is a perennial herbaceous legume with superior forage quality. It is the most important forage crop in the world and it was the first domesticated forage crop. Alfalfa is able to fix nitrogen from the air through a symbiotic relationship with Rhizobium bacteria with N production 7.85 – 10.37 g/m2. Its rooting system can reach 4.5 m that allows it to escape drought. Forage production can reach 15.48 tons of dry matter per ha/year and containing 18.0 – 29.1 % crude protein. Plants can live 3 to 12 years depending on climatic conditions and crop varieties. However, alfalfa is not a tropical plant, thus it has not been widely cultivated in Indonesia. The problem of alfalfa cultivation are high pest attacks and competition with weeds. Therefore, alfalfa cultivation requires attention and good management to obtain optimum yield.

  3. Evaluation of ensilage potential of alfalfa cultivars (Medicago sativa L.)

    OpenAIRE

    Monteiro, ALG; Costa,Ciniro; Arrigoni, M. D.

    1998-01-01

    The objective of this trial was to study the ensilage potential of alfalfa (Medicago sativa L,.). The material used in the evaluation was harvested from an experiment in a complete randomized blocks design with three replicates, with seventeen alfalfa cultivars, Criouil, Florida 77, P555, P581, Moapa, Gilboa, 34 Linea, C/W 8754, C/W 4468, C/W 86, C/W 8746, Hunter Field, Trifecta, Sequel, CUF 101, Aurora e Siriver, during three years. The harvest used for the determinations was collected at 30...

  4. Genetic Engineering of Alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Wang, Dan; Khurshid, Muhammad; Sun, Zhan Min; Tang, Yi Xiong; Zhou, Mei Liang; Wu, Yan Min

    2016-01-01

    Alfalfa is excellent perennial legume forage for its extensive ecological adaptability, high nutrition value, palatability and biological nitrogen fixation. It plays a very important role in the agriculture, animal husbandry and ecological construction. It is cultivated in all continents. With the development of modern plant breeding and genetic engineering techniques, a large amount of work has been carried out on alfalfa. Here we summarize the recent research advances in genetic engineering of alfalfa breeding, including transformation, quality improvement, stress resistance and as a bioreactor. The review article can enables us to understand the research method, direction and achievements of genetic engineering technology of Alfalfa.

  5. Beta-Amylases from Alfalfa (Medicago sativa L.) Roots.

    Science.gov (United States)

    Doehlert, D C; Duke, S H; Anderson, L

    1982-05-01

    Amylase was found in high activity (193 international units per milligram protein) in the tap root of alfalfa (Medicago sativa L. cv. Sonora). The activity was separated by gel filtration chromatography into two fractions with molecular weights of 65,700 (heavy amylase) and 41,700 (light amylase). Activity staining of electrophoretic gels indicated the presence of one isozyme in the heavy amylase fraction and two in the light amylase fraction. Three amylase isozymes with electrophoretic mobilities identical to those in the heavy and the light amylase fractions were the only amylases identified in crude root preparations. Both heavy and light amylases hydrolyzed amylopectin, soluble starch, and amylose but did not hydrolyze pullulan or beta-limit dextrin. The ratio of viscosity change to reducing power production during starch hydrolysis was identical for both alfalfa amylase fractions and sweet potato beta-amylase, while that of bacterial alpha-amylase was considerably higher. The identification of maltose and beta-limit dextrin as hydrolytic end-products confirmed that these alfalfa root amylases are all beta-amylases.The pH optimum for both beta-amylase fractions was 6.0. Both light and heavy beta-amylases showed normal Michaelis-Menten kinetics, with soluble starch as substrate, and had respectively K(m) values of 5.9 and 6.8 milligrams starch per milliliter and V(max) of 640 and 130 international units per milligram protein. Arrhenius plots indicated that the energy of activation for the heavy beta-amylase remained relatively unchanged (12.7 to 13.0 kilocalories per mole) from 0 to 30 degrees C, whereas the energy of activation for the light amylase increased from 12.0 to about 28.0 kilocalories per mole at 8.7 degrees C as temperature was lowered. The light amylase was shown to be inhibited by maltose.

  6. Induction of peroxidases and superoxide dismutases in transformed embryogenic calli of alfalfa (Medicago sativa L.)

    Science.gov (United States)

    Activities of peroxidase (POD) and superoxide dismutase (SOD) enzymes were analyzed in non-regenerative transformed embryogenic lines of alfalfa (Medicago sativa L.) carrying wound-inducible oryzacystatin I (OC-I), wound-inducible oryzacystatin I antisense (OC-Ias) or hygromycin phosphotransferase (...

  7. Occurrence of Transgenic Feral Alfalfa (Medicago sativa subsp. sativa L.) in Alfalfa Seed Production Areas in the United States.

    Science.gov (United States)

    Greene, Stephanie L; Kesoju, Sandya R; Martin, Ruth C; Kramer, Matthew

    2015-01-01

    The potential environmental risks of transgene exposure are not clear for alfalfa (Medicago sativa subsp. sativa), a perennial crop that is cross-pollinated by insects. We gathered data on feral alfalfa in major alfalfa seed-production areas in the western United States to (1) evaluate evidence that feral transgenic plants spread transgenes and (2) determine environmental and agricultural production factors influencing the location of feral alfalfa, especially transgenic plants. Road verges in Fresno, California; Canyon, Idaho; and Walla Walla, Washington were surveyed in 2011 and 2012 for feral plants, and samples were tested for the CP4 EPSPS protein that conveys resistance to glyphosate. Of 4580 sites surveyed, feral plants were observed at 404 sites. Twenty-seven percent of these sites had transgenic plants. The frequency of sites having transgenic feral plants varied among our study areas. Transgenic plants were found in 32.7%, 21.4.7% and 8.3% of feral plant sites in Fresno, Canyon and Walla Walla, respectively. Spatial analysis suggested that feral populations started independently and tended to cluster in seed and hay production areas, places where seed tended to drop. Significant but low spatial auto correlation suggested that in some instances, plants colonized nearby locations. Neighboring feral plants were frequently within pollinator foraging range; however, further research is needed to confirm transgene flow. Locations of feral plant clusters were not well predicted by environmental and production variables. However, the likelihood of seed spillage during production and transport had predictive value in explaining the occurrence of transgenic feral populations. Our study confirms that genetically engineered alfalfa has dispersed into the environment, and suggests that minimizing seed spillage and eradicating feral alfalfa along road sides would be effective strategies to minimize transgene dispersal.

  8. Occurrence of Transgenic Feral Alfalfa (Medicago sativa subsp. sativa L. in Alfalfa Seed Production Areas in the United States.

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    Stephanie L Greene

    Full Text Available The potential environmental risks of transgene exposure are not clear for alfalfa (Medicago sativa subsp. sativa, a perennial crop that is cross-pollinated by insects. We gathered data on feral alfalfa in major alfalfa seed-production areas in the western United States to (1 evaluate evidence that feral transgenic plants spread transgenes and (2 determine environmental and agricultural production factors influencing the location of feral alfalfa, especially transgenic plants. Road verges in Fresno, California; Canyon, Idaho; and Walla Walla, Washington were surveyed in 2011 and 2012 for feral plants, and samples were tested for the CP4 EPSPS protein that conveys resistance to glyphosate. Of 4580 sites surveyed, feral plants were observed at 404 sites. Twenty-seven percent of these sites had transgenic plants. The frequency of sites having transgenic feral plants varied among our study areas. Transgenic plants were found in 32.7%, 21.4.7% and 8.3% of feral plant sites in Fresno, Canyon and Walla Walla, respectively. Spatial analysis suggested that feral populations started independently and tended to cluster in seed and hay production areas, places where seed tended to drop. Significant but low spatial auto correlation suggested that in some instances, plants colonized nearby locations. Neighboring feral plants were frequently within pollinator foraging range; however, further research is needed to confirm transgene flow. Locations of feral plant clusters were not well predicted by environmental and production variables. However, the likelihood of seed spillage during production and transport had predictive value in explaining the occurrence of transgenic feral populations. Our study confirms that genetically engineered alfalfa has dispersed into the environment, and suggests that minimizing seed spillage and eradicating feral alfalfa along road sides would be effective strategies to minimize transgene dispersal.

  9. Complete nucleotide sequence of Alfalfa mosaic virus isolated from alfalfa (Medicago sativa L.) in Argentina.

    Science.gov (United States)

    Trucco, Verónica; de Breuil, Soledad; Bejerman, Nicolás; Lenardon, Sergio; Giolitti, Fabián

    2014-06-01

    The complete nucleotide sequence of an Alfalfa mosaic virus (AMV) isolate infecting alfalfa (Medicago sativa L.) in Argentina, AMV-Arg, was determined. The virus genome has the typical organization described for AMV, and comprises 3,643, 2,593, and 2,038 nucleotides for RNA1, 2 and 3, respectively. The whole genome sequence and each encoding region were compared with those of other four isolates that have been completely sequenced from China, Italy, Spain and USA. The nucleotide identity percentages ranged from 95.9 to 99.1 % for the three RNAs and from 93.7 to 99 % for the protein 1 (P1), protein 2 (P2), movement protein and coat protein (CP) encoding regions, whereas the amino acid identity percentages of these proteins ranged from 93.4 to 99.5 %, the lowest value corresponding to P2. CP sequences of AMV-Arg were compared with those of other 25 available isolates, and the phylogenetic analysis based on the CP gene was carried out. The highest percentage of nucleotide sequence identity of the CP gene was 98.3 % with a Chinese isolate and 98.6 % at the amino acid level with four isolates, two from Italy, one from Brazil and the remaining one from China. The phylogenetic analysis showed that AMV-Arg is closely related to subgroup I of AMV isolates. To our knowledge, this is the first report of a complete nucleotide sequence of AMV from South America and the first worldwide report of complete nucleotide sequence of AMV isolated from alfalfa as natural host.

  10. Crystal structure of isoflavone reductase from alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Wang, Xiaoqiang; He, Xianzhi; Lin, Jianqiao; Shao, Hui; Chang, Zhenzhan; Dixon, Richard A

    2006-05-19

    Isoflavonoids play important roles in plant defense and exhibit a range of mammalian health-promoting activities. Isoflavone reductase (IFR) specifically recognizes isoflavones and catalyzes a stereospecific NADPH-dependent reduction to (3R)-isoflavanone. The crystal structure of Medicago sativa IFR with deletion of residues 39-47 has been determined at 1.6A resolution. Structural analysis, molecular modeling and docking, and comparison with the structures of other NADPH-dependent enzymes, defined the putative binding sites for co-factor and substrate and potential key residues for enzyme activity and substrate specificity. Further mutagenesis has confirmed the role of Lys144 as a catalytic residue. This study provides a structural basis for understanding the enzymatic mechanism and substrate specificity of IFRs as well as the functions of IFR-like proteins.

  11. Micromonospora from nitrogen fixing nodules of alfalfa (Medicago sativa L.). A new promising Plant Probiotic Bacteria.

    OpenAIRE

    Pilar Martínez-Hidalgo; Purificación Galindo-Villardón; Trujillo, Martha E.; Igual, José M.; Eustoquio Martínez-Molina

    2014-01-01

    Biotic interactions can improve agricultural productivity without costly and environmentally challenging inputs. Micromonospora strains have recently been reported as natural endophytes of legume nodules but their significance for plant development and productivity has not yet been established. The aim of this study was to determine the diversity and function of Micromonospora isolated from Medicago sativa root nodules. Micromonospora-like strains from field alfalfa nodules were characteri...

  12. Concerted changes in N and C primary metabolism in alfalfa (Medicago sativa) under water restriction

    OpenAIRE

    Aranjuelo, Iker; Tcherkez, Guillaume,; Molero, Gemma; Gilard, Françoise; AVICE, JEAN-CHRISTOPHE; Nogués, Salvador

    2013-01-01

    Although the mechanisms of nodule N2 fixation in legumes are now well documented, some uncertainty remains on the metabolic consequences of water deficit. In most cases, little consideration is given to other organs and, therefore, the coordinated changes in metabolism in leaves, roots, and nodules are not well known. Here, the effect of water restriction on exclusively N2-fixing alfalfa (Medicago sativa L.) plants was investigated, and proteomic, metabolomic, and physiological analyses were ...

  13. Environmental Impact Research Program: Alfalfa (Medicago sativa). Section 7.3.1, U.S. Army Corps of Engineers Wildlife Resources Management Manual.

    Science.gov (United States)

    1986-07-01

    ADAl?3 141 ENVIRONMENTAL IMPACT RESEARCH PROGRAM: ALFALFA 1/1 ( MEDICAGO SATIVA ) SECTION 7..(U) ARMY ENGINEER7F R ?’ 4 N OM ENRATERWAYS EXPERIMENT... Medicago sativa ) Section 7.3.1, US ARMY CORPS OF ENGINEERS WILDLIFE RESOURCES MANAGEMENT MANUAL CV) P% by Clinton H. Wasser Colorado State University Fort...20314-1000 EIRP 31631.. 11 TITLE (Include Security Classification) Alfalfa ( Medicago sativa ): Section 7.3.1, US Army Corps of Engineers Wildlife

  14. Accumulation and residue of napropamide in alfalfa (Medicago sativa) and soil involved in toxic response.

    Science.gov (United States)

    Cui, Li E; Yang, Hong

    2011-06-15

    Napropamide belongs to the amide herbicide family and widely used to control weeds in farmland. Intensive use of the herbicide has resulted in widespread contamination to ecosystems. The present study demonstrated an analysis on accumulation of the toxic pesticide napropamide in six genotypes of alfalfa (Medicago sativa), along with biological parameters and its residues in soils. Soil was treated with napropamide at 3 mg kg(-1) dry soil and alfalfa plants were cultured for 10 or 30 d, respectively. The maximum value for napropamide accumulation is 0.426 mg kg(-1) in shoots and 2.444 mg kg(-1) in roots. The napropamide-contaminated soil with alfalfa cultivation had much lower napropamide concentrations than the control (soil without alfalfa cultivation). Also, the content of napropamide residue in the rhizosphere was significantly lower than that in the non-rhizosphere soil. M. sativa exposed to 3 mg kg(-1) napropamide showed inhibited growth. Further analysis revealed that plants treated with napropamide accumulated more reactive oxygen species (O(2)(-) and H(2)O(2)) and less amounts of chlorophyll. However, not all cultivars showed oxidative injury, suggesting that the alfalfa cultivars display different tolerance to napropamide.

  15. [Natural nucleotide polymorphism of the Srlk gene that determines salt stress tolerance in alfalfa (Medicago sativa L)].

    Science.gov (United States)

    Vishnevskaia, M S; Pavlov, A V; Dziubenko, E A; Dziubenko, N I; Potokina, E K

    2014-04-01

    Based on legume genome syntheny, the nucleotide sequence of Srlk gene, key role of which in response to salt stress was demonstrated for the model species Medicago truncatula, was identified in the major forage and siderate crop alfalfa (Medicago sativa). In twelve alfalfa samples originating from regions with contrasting growing conditions, 19 SNPs were revealed in the Srlk gene. For two nonsynonymous SNPs, molecular markers were designed that could be further used to analyze the association between Srlk gene nucleotide polymorphism and the variability in salt stress tolerance among alfalfa cultivars.

  16. [Determination of Hard Rate of Alfalfa (Medicago sativa L.) Seeds with Near Infrared Spectroscopy].

    Science.gov (United States)

    Wang, Xin-xun; Chen, Ling-ling; Zhang, Yun-wei; Mao, Pei-sheng

    2016-03-01

    Alfalfa (Medicago sativa L.) is the most commonly grown forage crop due to its better quality characteristics and high adaptability in China. However, there was 20%-80% hard seeds in alfalfa which could not be identified easily from non hard seeds which would cause the loss of seed utilization value and plant production. This experiment was designed for 121 samples of alfalfa. Seeds were collected according to different regions, harvested year and varieties. 31 samples were artificial matched as hard rates ranging from 20% to 80% to establish a model for hard seed rate by near infrared spectroscopy (NIRS) with Partial Least Square (PLS). The objective of this study was to establish a model and to estimate the efficiency of NIRS for determining hard rate of alfalfa seeds. The results showed that the correlation coefficient (R2(cal)) of calibration model was 0.981 6, root mean square error of cross validation (RMSECV) was 5.32, and the ratio of prediction to deviation (RPD) was 3.58. The forecast model in this experiment presented the satisfied precision. The proposed method using NIRS technology is feasible for identification and classification of hard seed in alfalfa. A new method, as nondestructive testing of hard seed rate, was provided to theoretical basis for fast nondestructive detection of hard seed rates in alfalfa.

  17. The Current Status, Problems, and Prospects of Alfalfa (Medicago sativa L. Breeding in China

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    Shangli Shi

    2017-01-01

    Full Text Available This paper reviews the current status, methodology, achievements, and prospects of alfalfa (Medicago sativa L. breeding in China. There are 77 cultivars that have been registered in the country, these include 36 cultivars bred through breeding programs, 17 introduced from overseas, 5 domesticated from wild ecotypes, and 19 through regional collection/breeding programs. Cultivars have been selected for cold resistance, disease resistance, salt tolerance, grazing tolerance, high yield, and early maturity. Most of these cultivars have been developed through conventional breeding techniques, such as selective and cross breeding, and some are now being evaluated that have been developed through the application of transgenic technology. The major problems for alfalfa breeding in China include low success rate, slow progress to breed resistant varieties, lack of breeding materials and their systematic collection, storage and evaluation, lack of advanced breeding techniques, and low adoption rate of new cultivars. There are gaps in alfalfa breeding between China and the developed world. Improvement of alfalfa breeding techniques, development of cultivars with adaptations to different regions within China, and the protection and utilization of alfalfa germplasm resources have been identified as major strategies to improve the efficiency of alfalfa breeding in China.

  18. Development of simple sequence repeat markers and diversity analysis in alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Wang, Zan; Yan, Hongwei; Fu, Xinnian; Li, Xuehui; Gao, Hongwen

    2013-04-01

    Efficient and robust molecular markers are essential for molecular breeding in plant. Compared to dominant and bi-allelic markers, multiple alleles of simple sequence repeat (SSR) markers are particularly informative and superior in genetic linkage map and QTL mapping in autotetraploid species like alfalfa. The objective of this study was to enrich SSR markers directly from alfalfa expressed sequence tags (ESTs). A total of 12,371 alfalfa ESTs were retrieved from the National Center for Biotechnology Information. Total 774 SSR-containing ESTs were identified from 716 ESTs. On average, one SSR was found per 7.7 kb of EST sequences. Tri-nucleotide repeats (48.8 %) was the most abundant motif type, followed by di-(26.1 %), tetra-(11.5 %), penta-(9.7 %), and hexanucleotide (3.9 %). One hundred EST-SSR primer pairs were successfully designed and 29 exhibited polymorphism among 28 alfalfa accessions. The allele number per marker ranged from two to 21 with an average of 6.8. The PIC values ranged from 0.195 to 0.896 with an average of 0.608, indicating a high level of polymorphism of the EST-SSR markers. Based on the 29 EST-SSR markers, assessment of genetic diversity was conducted and found that Medicago sativa ssp. sativa was clearly different from the other subspecies. The high transferability of those EST-SSR markers was also found for relative species.

  19. Modeling of desorption of Alfalfa (Medicago sativa) stems and leaves.

    NARCIS (Netherlands)

    ArabHosseini, A.; Huisman, W.; Müller, J.

    2011-01-01

    The equilibrium moisture content of agricultural products is necessary to optimize drying process and helps to keep the quality of the product during the period of storage. The main aim of this research was to find the best model which could define well, the exchange of moisture between alfalfa (Med

  20. PHENOTYPIC DIVERSITY OF ALFALFA (MEDICAGO SATIVA L. GERMPLASM

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    Marijana Tucak

    2011-06-01

    Full Text Available The objective of this study was to evaluate phenotypic diversity in the alfalfa germplasm collections using multivariate analysis to examine the extent of genetic diversity and contribution of selected characters to the total diversity and finally to select the most promising clusters/populations for further breeding work. Forty alfalfa populations/cultivars of different geographical origin were evaluated for 12 agro-morphological characters during two consecutive years. The populations/ cultivars were grouped into six clusters. In most cases populations/cultivars within clusters were not associated with their geographical origin. Intercluster distances were larger than the intracluster ones. This research revealed a broad phenotypic diversity within and between the alfalfa germplasm collections. The following characters contributed most to the total phenotypic diversity: dry matter yield in the first production year, plant height and length of central leaflet. Based on the mean value of the evaluated characters and determined distances between clusters, the most promising populations/cultivars belong to the clusters IV and V. Selected populations/cultivars could be considered as a valuable genetic material for the yield and quality improvement of alfalfa in our breeding programme.

  1. Proteomic Identification of Differentially Expressed Proteins during Alfalfa (Medicago sativa L.) Flower Development.

    Science.gov (United States)

    Chen, Lingling; Chen, Quanzhu; Zhu, Yanqiao; Hou, Longyu; Mao, Peisheng

    2016-01-01

    Flower development, pollination, and fertilization are important stages in the sexual reproduction process of plants; they are also critical steps in the control of seed formation and development. During alfalfa (Medicago sativa L.) seed production, some distinct phenomena such as a low seed setting ratio, serious flower falling, and seed abortion commonly occur. However, the causes of these phenomena are complicated and largely unknown. An understanding of the mechanisms that regulate alfalfa flowering is important in order to increase seed yield. Hence, proteomic technology was used to analyze changes in protein expression during the stages of alfalfa flower development. Flower samples were collected at pre-pollination (S1), pollination (S2), and the post-pollination senescence period (S3). Twenty-four differentially expressed proteins were successfully identified, including 17 down-regulated in pollinated flowers, one up-regulated in pollinated and senesced flowers, and six up-regulated in senesced flowers. The largest proportions of the identified proteins were involved in metabolism, signal transduction, defense response, oxidation reduction, cell death, and programmed cell death (PCD). Their expression profiles demonstrated that energy metabolism, carbohydrate metabolism, and amino acid metabolism provided the nutrient foundation for pollination in alfalfa. Furthermore, there were three proteins involved in multiple metabolic pathways: dual specificity kinase splA-like protein (kinase splALs), carbonic anhydrase, and NADPH: quinone oxidoreductase-like protein. Expression patterns of these proteins indicated that MAPK cascades regulated multiple processes, such as signal transduction, stress response, and cell death. PCD also played an important role in the alfalfa flower developmental process, and regulated both pollination and flower senescence. The current study sheds some light on protein expression profiles during alfalfa flower development and

  2. Proteomic Identification of Differentially Expressed Proteins during Alfalfa (Medicago sativa L.) Flower Development

    Science.gov (United States)

    Chen, Lingling; Chen, Quanzhu; Zhu, Yanqiao; Hou, Longyu; Mao, Peisheng

    2016-01-01

    Flower development, pollination, and fertilization are important stages in the sexual reproduction process of plants; they are also critical steps in the control of seed formation and development. During alfalfa (Medicago sativa L.) seed production, some distinct phenomena such as a low seed setting ratio, serious flower falling, and seed abortion commonly occur. However, the causes of these phenomena are complicated and largely unknown. An understanding of the mechanisms that regulate alfalfa flowering is important in order to increase seed yield. Hence, proteomic technology was used to analyze changes in protein expression during the stages of alfalfa flower development. Flower samples were collected at pre-pollination (S1), pollination (S2), and the post-pollination senescence period (S3). Twenty-four differentially expressed proteins were successfully identified, including 17 down-regulated in pollinated flowers, one up-regulated in pollinated and senesced flowers, and six up-regulated in senesced flowers. The largest proportions of the identified proteins were involved in metabolism, signal transduction, defense response, oxidation reduction, cell death, and programmed cell death (PCD). Their expression profiles demonstrated that energy metabolism, carbohydrate metabolism, and amino acid metabolism provided the nutrient foundation for pollination in alfalfa. Furthermore, there were three proteins involved in multiple metabolic pathways: dual specificity kinase splA-like protein (kinase splALs), carbonic anhydrase, and NADPH: quinone oxidoreductase-like protein. Expression patterns of these proteins indicated that MAPK cascades regulated multiple processes, such as signal transduction, stress response, and cell death. PCD also played an important role in the alfalfa flower developmental process, and regulated both pollination and flower senescence. The current study sheds some light on protein expression profiles during alfalfa flower development and

  3. Proteomic identification of differentially expressed proteins during alfalfa (Medicago sativa L. flower development

    Directory of Open Access Journals (Sweden)

    Lingling Chen

    2016-10-01

    Full Text Available Flower development, pollination, and fertilization are important stages in the sexual reproduction process of plants; they are also critical steps in the control of seed formation and development. During alfalfa (Medicago sativa L. seed production, some distinct phenomena such as a low seed setting ratio, serious flower falling, and seed abortion commonly occur. However, the causes of these phenomena are complicated and largely unknown. An understanding of the mechanisms that regulate alfalfa flowering is important in order to increase seed yield. Hence, proteomic technology was used to analyze changes in protein expression during the stages of alfalfa flower development. Flower samples were collected at pre-pollination (S1, pollination (S2, and the post-pollination senescence period (S3. Twenty-four differentially expressed proteins were successfully identified, including 17 down-regulated in pollinated flowers, one up-regulated in pollinated and senesced flowers, and six up-regulated in senesced flowers. The largest proportions of the identified proteins were involved in metabolism, signal transduction, defense response, oxidation reduction, cell death, and programmed cell death (PCD. Their expression profiles demonstrated that energy metabolism, carbohydrate metabolism, and amino acid metabolism provided the nutrient foundation for pollination in alfalfa. Furthermore, there were three proteins involved in multiple metabolic pathways: dual specificity kinase splA-like protein (kinase splALs, carbonic anhydrase (CA, and NADPH: quinone oxidoreductase-like protein (NQOLs. Expression patterns of these proteins indicated that MAPK cascades regulated multiple processes, such as signal transduction, stress response, and cell death. PCD also played an important role in the alfalfa flower developmental process, and regulated both pollination and flower senescence. The current study sheds some light on protein expression profiles during alfalfa flower

  4. Detection of QTL for forage yield, lodging resistance and spring vigor traits in alfalfa (Medicago sativa L.)

    Science.gov (United States)

    Alfalfa (Medicago sativa L.) is an internationally significant forage crop. Forage yield, lodging resistance and spring vigor are important agronomic traits conditioned by quantitative genetic and environmental effects. The objective of this study was to identify quantitative trait loci (QTL) and mo...

  5. Effect of alfalfa (medicago sativa) on fermentation profile and nutritive value of switchgrass (panicum virgatum) and bermudagrass (cynodon dactylon) silages

    Science.gov (United States)

    An experiment was conducted at the University of Kentucky Spindletop Farm in Lexington, Kentucky between October and November, 2009 to evaluate the effect of different percentages of alfalfa (Medicago sativa) as mixtures in switchgrass (Panicum virgatus) and bermudagrass (Cynodon dactylon) silages. ...

  6. THE EFFECT OF PRIMING ON GERMINATION AND SEEDLING GROWTH OF ALFALFA (MEDICAGO SATIVA L.) UNDER SALINITY STRESS

    OpenAIRE

    Jorjandi M.; SHARIFI SIRCHI G.R.

    2012-01-01

    Salinity stress is an abiotic stress which has harmful effects on germination, growth and yield of alfalfa (Medicago sativa L.) in many parts of the world. Seed priming is a way of increasing salt tolerance of plants. In this study, the effect of seed priming on germination and growth of alfalfa seedlings, Bami cultivar, under salinity condition was investigated. According to germination percentage of seeds under In vitro conditions, salicylic acid, Vitamin B12 and distilled water were select...

  7. Micromonospora from nitrogen fixing nodules of alfalfa (Medicago sativa L.). A new promising Plant Probiotic Bacteria.

    Science.gov (United States)

    Martínez-Hidalgo, Pilar; Galindo-Villardón, Purificación; Trujillo, Martha E; Igual, José M; Martínez-Molina, Eustoquio

    2014-09-17

    Biotic interactions can improve agricultural productivity without costly and environmentally challenging inputs. Micromonospora strains have recently been reported as natural endophytes of legume nodules but their significance for plant development and productivity has not yet been established. The aim of this study was to determine the diversity and function of Micromonospora isolated from Medicago sativa root nodules. Micromonospora-like strains from field alfalfa nodules were characterized by BOX-PCR fingerprinting and 16S rRNA gene sequencing. The ecological role of the interaction of the 15 selected representative Micromonospora strains was tested in M. sativa. Nodulation, plant growth and nutrition parameters were analyzed. Alfalfa nodules naturally contain abundant and highly diverse populations of Micromonospora, both at the intra- and at interspecific level. Selected Micromonospora isolates significantly increase the nodulation of alfalfa by Ensifer meliloti 1021 and also the efficiency of the plant for nitrogen nutrition. Moreover, they promote aerial growth, the shoot-to-root ratio, and raise the level of essential nutrients. Our results indicate that Micromonospora acts as a Rhizobia Helper Bacteria (RHB) agent and has probiotic effects, promoting plant growth and increasing nutrition efficiency. Its ecological role, biotechnological potential and advantages as a plant probiotic bacterium (PPB) are also discussed.

  8. Screening of Cd tolerant genotypes and isolation of metallothionein genes in alfalfa (Medicago sativa L.)

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xiaojuan, E-mail: xiaojuanwang@lzu.edu.cn [School of Pastoral Agriculture Science and Technology, Lanzhou University, P.O. Box 61, Lanzhou 730020 (China); Song, Yu [School of Pastoral Agriculture Science and Technology, Lanzhou University, P.O. Box 61, Lanzhou 730020 (China); Environment Management College of China, Qinhuangdao 066004 (China); Ma Yanhua [Hebei Normal University of Science and Technology, Qinhuangdao 066004 (China); Zhuo Renying [Key Lab of Tree Genomics, Research Institute of Subtropical of Forest, Chinese Academy of Forest, Fuyang 311400 (China); Jin Liang [School of Pastoral Agriculture Science and Technology, Lanzhou University, P.O. Box 61, Lanzhou 730020 (China)

    2011-12-15

    In order to evaluate Cd tolerance in wide-ranging sources of alfalfa (Medicago sativa) and to identify Cd tolerant genotypes which may potentially be useful for restoring Cd-contaminated environments, thirty-six accessions of alfalfa were screened under hydroponic culture. Our results showed that the relative root growth rate varied from 0.48 to 1.0, which indicated that different alfalfa accessions had various responses to Cd stress. The candidate fragments derived from differentially expressed metallothionein (MT) genes were cloned from leaves of two Cd tolerant genotypes, YE and LZ. DNA sequence and the deduced protein sequence showed that MsMT2a and MsMT2b had high similarity to those in leguminous plants. DDRT-PCR analysis showed that MsMT2a expressed in both YE and LZ plants under control and Cd stress treatment, but MsMT2b only expressed under Cd stress treatment. This suggested that MsMT2a was universally expressed in leaves of alfalfa but expression of MsMT2b was Cadmium (Cd) inducible. - Highlights: > Evaluate Cd tolerance in wide sources of alfalfa accessions. > Identify Cd-hyperaccumulators potentially useful for restoring Cd-contaminated environments. > Cloned differentially expressed metallothionein (MT) genes. > Characteristics and deduced protein sequence of MsMT2a and MsMT2b were analyzed. > MsMT2a might be a universally gene of alfalfa but MsMT2b might be an inductive gene. - Two Cd tolerant alfalfa genotypes were screened and their metallothionein genes were cloned which showed that MsMT2a was universally expressed but MsMT2b was Cd inducible expression.

  9. Uptake of oxytetracycline and its phytotoxicity to alfalfa (Medicago sativa L.)

    Energy Technology Data Exchange (ETDEWEB)

    Kong, W.D. [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Zhu, Y.G. [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China)]. E-mail: ygzhu@rcees.ac.cn; Liang, Y.C. [Ministry of Agriculture Key Laboratory of Plant Nutrition and Nutrient Cycling, Institute of Soils and Fertilizers, Chinese Academy of Agricultural Sciences, Beijing 100081 (China); Zhang, J. [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Smith, F.A. [Soil and Land Systems, School of Earth and Environmental Sciences, University of Adelaide, DP 636, Adelaide, SA 5005 (Australia); Yang, M. [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China)

    2007-05-15

    A series of experiments were conducted in a hydroponic system to investigate the uptake of oxytetracycline (OTC) and its toxicity to alfalfa (Medicago sativa L.). OTC inhibited alfalfa shoot and root growth by up to 61% and 85%, respectively. The kinetics of OTC uptake could be well described by Michaelis-Menten equation with V {sub max} of 2.25 {mu}mol g{sup -1} fresh weight h{sup -1}, and K {sub m} of 0.036 mM. The uptake of OTC by alfalfa was strongly inhibited by the metabolic inhibitor, 2,4-DNP (2,4-dinitrophenol), at pH 3.5 and 6.0, but not by the aquaporin competitors, glycerol and Ag{sup +}. OTC uptake, however, was significantly inhibited by Hg{sup 2+}, suggesting that the inhibition of influx was due to general cellular stress rather than the specific action of Hg{sup 2+} on aquaporins. Results from the present study suggested that OTC uptake into alfalfa is an energy-dependent process. - Plant uptake of antibiotic oxytetracycline is energy-dependent.

  10. Selective lignin downregulation leads to constitutive defense response expression in alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Gallego-Giraldo, Lina; Jikumaru, Yusuke; Kamiya, Yuji; Tang, Yuhong; Dixon, Richard A

    2011-05-01

    • Downregulation of hydroxycinnamoyl CoA: shikimate hydroxycinnamoyl transferase (HCT) in alfalfa (Medicago sativa) reduces lignin levels and improves forage quality and saccharification efficiency for bioethanol production. However, the plants have reduced stature. It was previously reported that HCT-down-regulated Arabidopsis have impaired auxin transport, but this has recently been disproved. • To address the basis for the phenotypes of lignin-modified alfalfa, we measured auxin transport, profiled a range of metabolites including flavonoids and hormones, and performed in depth transcriptome analyses. • Auxin transport is unaffected in HCT antisense alfalfa despite increased flavonoid biosynthesis. The plants show increased cytokinin and reduced auxin levels, and gibberellin levels and sensitivity are both reduced. Levels of salicylic, jasmonic and abscisic acids are elevated, associated with massive upregulation of pathogenesis and abiotic stress-related genes and enhanced tolerance to fungal infection and drought. • We suggest that HCT downregulated alfalfa plants exhibit constitutive activation of defense responses, triggered by release of bioactive cell wall fragments and production of hydrogen peroxide as a result of impaired secondary cell wall integrity.

  11. Screening of Cd tolerant genotypes and isolation of metallothionein genes in alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Wang, Xiaojuan; Song, Yu; Ma, Yanhua; Zhuo, Renying; Jin, Liang

    2011-12-01

    In order to evaluate Cd tolerance in wide-ranging sources of alfalfa (Medicago sativa) and to identify Cd tolerant genotypes which may potentially be useful for restoring Cd-contaminated environments, thirty-six accessions of alfalfa were screened under hydroponic culture. Our results showed that the relative root growth rate varied from 0.48 to 1.0, which indicated that different alfalfa accessions had various responses to Cd stress. The candidate fragments derived from differentially expressed metallothionein (MT) genes were cloned from leaves of two Cd tolerant genotypes, YE and LZ. DNA sequence and the deduced protein sequence showed that MsMT2a and MsMT2b had high similarity to those in leguminous plants. DDRT-PCR analysis showed that MsMT2a expressed in both YE and LZ plants under control and Cd stress treatment, but MsMT2b only expressed under Cd stress treatment. This suggested that MsMT2a was universally expressed in leaves of alfalfa but expression of MsMT2b was Cadmium (Cd) inducible.

  12. Photosynthate partitioning and nitrogen fixation of alfalfa and birdsfoot trefoil. [Lotus corniculatus L. ; Medicago sativa L

    Energy Technology Data Exchange (ETDEWEB)

    Shieh, W.J.

    1985-01-01

    Nodule mass and number are usually correlated with rates of nitrogen fixation in legumes. Birdsfoot trefoil (Lotus corniculatus L.) with more than twice the nodule number and mass, however, fixes far less nitrogen than alfalfa (Medicago sativa L.) at the same age. In this research, photosynthesis and photosynthate partitioning and utilization in relation to nitrogen fixation of alfalfa and birdsfoot trefoil were examined in order to determine their relationship to nitrogen fixation potential. Photosynthate to nodules was studied using /sup 14/CO/sub 2/ labeling techniques. Partitioning patterns were altered by shading and dark depletion treatments. Efficiency of photosynthate utilization was examined by determining turnover of /sup 14/C photosynthate in nodule metabolites and by studying rates of cyanide-resistant and cyanide-sensitive O/sub 2/ uptake. Alfalfa nodule activity was greater than trefoil expressed on a hole pot or nodule dry weight basis. Both shading and dark treatments significantly reduced nodule activity as estimated by the acetylene reduction assay. Shoots of both species were found to be the dominant sinks for photosynthate. Percentage /sup 14/C recovered in alfalfa roots was more than twice that of trefoil at 1,2,3,4 and 24 h after labeling. Greater relative specific radioactivity (RSA) in nodules of both species suggests that they were stronger sinks for current photosynthate than roots.

  13. Evaluation of Selection Indices for Alfalfa (Medicago sativa L.

    Directory of Open Access Journals (Sweden)

    Hassan MONIRIFAR

    2010-03-01

    Full Text Available In order to evaluate the efficiency of selection indices in alfalfa improvement, an experiment was conducted from 2000 to 2007 at East Azarbaijan Agricultural and Natural Resources Research Center, Iran. A set of 29 native ecotypes, which were collected in 2000 and 2001 from Azerbaijan (Iran, together with one improved variety were used to conduct a polycross nursery. For the purpose of random mating, a randomized complete block design was used with 12 replications arranged in this nursery. The resulting 30 half-sib families were planted individually in pots and the 30 days old seedlings were transplanted to the field in May, 2004. Each 3-row plot consisted of 45 HS plants. Several traits, such as individual plants� fresh weight and individual plants� dry weight (IPFW, IPDW, number of shoots per plant (NS and plant height (PH in each harvest and also, days until 10% flowering, the ratio of fresh and dry weight of leaves/plant and size of trifoliate leaves were measured for three cropping seasons. The results of analysis of variance showed large variation among polycross progenies. Six selection indices (Ii with different number of traits at adult plant stage were evaluated. Based on the result of this investigation, if number of shoots and height of adult plant, excluding yield, are recorded, I2 is suggested. If, in addition to fresh yield, height of adult plant is measured, I6 is recommended. I4 is useful when number of shoots and plant height with dry yield are included in the index. In conclusion, the importance of mature plant traits in selection indices was in the order of yield > plant height > number of shoots. The results provided more evidence that selection indices incorporating the component of dry yield are more advantageous. The most efficient selection index consisted of NS, IPDW and PH, having a relative efficiency of 280%.

  14. Toxic effects of copper-based nanoparticles or compounds to lettuce (Lactuca sativa) and alfalfa (Medicago sativa).

    Science.gov (United States)

    Hong, Jie; Rico, Cyren M; Zhao, Lijuan; Adeleye, Adeyemi S; Keller, Arturo A; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L

    2015-01-01

    The increased production and use of nanoparticles (NPs) has generated concerns about their impact on living organisms. In this study, nCu, bulk Cu, nCuO, bulk CuO, Cu(OH)2 (CuPRO 2005, Kocide 3000), and CuCl2 were exposed for 15 days to 10 days-old hydroponically grown lettuce (Lactuca sativa) and alfalfa (Medicago sativa). Each compound was applied at 0, 5, 10, and 20 mg L(-1). At harvest, we measured the size of the plants and determined the concentration of Cu, macro and microelements by using ICP-OES. Catalase and ascorbate peroxidase activity was also determined. Results showed that all Cu NPs/compounds reduced the root length by 49% in both plant species. All Cu NPs/compounds increased Cu, P, and S (>100%, >50%, and >20%, respectively) in alfalfa shoots and decreased P and Fe in lettuce shoot (>50% and >50%, respectively, excluding Fe in CuCl2 treatment). Biochemical assays showed reduced catalase activity in alfalfa (root and shoot) and increased ascorbate peroxidase activity in roots of both plant species. Results suggest that Cu NPs/compounds not only reduced the size of the plants but altered nutrient content and enzyme activity in both plant species.

  15. Enhanced salt tolerance of alfalfa (Medicago sativa) by rstB gene transformation.

    Science.gov (United States)

    Zhang, Wan-Jun; Wang, Tao

    2015-05-01

    Generating salt tolerance forage plant is essential for use of the land affected by high salinity. A salt tolerance gene rstB was used as a selectable marker gene in Agrobacterium-mediated transformation of tobacco under a selective regime of 170mM NaCl. The transgenic plants showed clear improvement in salt tolerance. To improve salt tolerance of alfalfa (Medicago sativa L.), rstB gene was introduced into alfalfa genome by Agrobacterium-mediated transformation. No abnormal phenotype was observed among the transgenic plants when compared with wild type (wt) plants. Significant enhancement of resistance to salt-shock treatment was noted on the rstB transgenic (T0) plants. Transgenic second-generation (T1) seeds showed improved germination rate and seedling growth under salt-stress condition. Hindered Na(+) accumulation, but enhanced Ca(2+) accumulation was observed on the rstB T1 plants when subjected to salt-stresses. Enhanced calcium accumulation in transgenic plants was also verified by cytohistochemical localization of calcium. Under salt-stress of 50mM NaCl, about 15% of the transgenic plants finished their life-cycle but the wt plants had no flower formation. The results demonstrated that the expression of rstB gene improved salt tolerance in transgenic alfalfa.

  16. Partitioning and mobilization of photoassimilate in alfalfa subjected to water deficits. [Medicago sativa L

    Energy Technology Data Exchange (ETDEWEB)

    Hall, M.H. (Univ. of Idaho, Moscow (USA)); Sheaffer, C.C.; Heichel, G.H. (Univ. of Minnesota, St. Paul (USA))

    Faster regrowth of a stressed alfalfa (Medicago sativa L.) crop compared to an unstressed crop after rewatering has been reported. The bases of this compensatory response are unknown, but they may be important to understanding adaptation to water stress and to developing crop water management strategies. The authors objectives was to determine the effect of stress induced by water deficit on photoassimilate partitioning and the utilization of stored assimilates during regrowth of alfalfa. Field and greenhouse experiments were conducted using cultivars differing in winterhardiness. Plants were subjected to water stress, pulse-labeled with {sup 14}CO{sub 2}, and sampled following 0, 1, 14, 21, and 28-d translocation periods. Following the 14-d sampling, herbage was harvested and water stress was removed. Cultivars contrasting in winterhardiness responded similarly to water stress. Stressed plant roots contained 73 and 114% more total plant radioactivity (TPR) than the control at the 1 and 14-d translocation periods, respectively. Water stress significantly increased root starch and TPR percentage in the starch fraction, but had much smaller effects on root soluble-sugar concentration and TPR percentage of the root sugar fraction. Herbage regrowth mass following harvest and rewatering of the water-stressed plants was similar to that of the control. Compared to the control, water-stressed alfalfa has greater total nonstructural carbohydrates in the roots, apparently due to increased photoassimilate partitioning to the roots. However, the greater root carbohydrate concentrations did not result in compensatory herbage regrowth following rewatering.

  17. Effect of UV-C on Drought Tolerance of Alfalfa (Medicago sativa Callus

    Directory of Open Access Journals (Sweden)

    Ali A. Ehsanpour

    2005-01-01

    Full Text Available Water stress and unfavorable climate decrease the growth and development of plant globally. Medicago is a valuable plant as a source of food for animal, foliage and for medicine. Since, Iran is located in a dry area; consequently, the study of plant responses to water stress is important. In this research UV-C radiation was used to induce physiological and genetic changes in alfalfa callus. In vitro grown calluses of M. sativa were exposed to UV-C for 0, 15, 30 and 60 min and then, were transferred to MS medium containing 0, 2, 5, 10, 20, 30% PEG. All explants were kept in the dark in the culture room. Calluses tolerate to osmotic stress were selected according to fresh weight. Results showed that radiation of UV-C for 60 min increased the osmotic tolerance and decreased the effect of drought stress.

  18. Weed control in dormant alfalfa (Medicago sativa L. with active ingredients’ metribuzin, imazetapyr and pronamide

    Directory of Open Access Journals (Sweden)

    Zvonko Pacanoski

    2017-03-01

    Full Text Available Field trials were conducted during 2008 – 2010 to evaluate weed control in dormant alfalfa (Medicago sativa L. with metribuzin, imazetapyr and pronamide. The weed population in all experimental years was consisted mainly of annual winter and spring grass and broadleaf weeds, and some perennial weeds. The number of weed species and weed density increased with the years of alfalfa growing, from second to the fourth year. Weed density in the untreated control plots was 201.0, 217.2 and 240.5 plants per m2 in 2008, 2009 and 2010, respectively. The most dominant weeds were Anthemis cotula, Capsell bursa-pastoris and Taraxacum officinale in 2008, Alopecurus myosuroides and Poa pratensis in 2009 and Millium vernale and Arabidopsis thaliana in 2010. Efficacy of herbicides in control of weeds was ranged of 91.8% (pronamide to 98.4% (metribuzin 1.0 kg*ha-1 in 2008, 93.1% (imazetapyr to 97.3% (metribuzin 1.0 kg*ha-1 in 2009 and 92.1% (imazetapyr to 97.3% (metribuzin 1.0 kg*ha-1 in 2010, respectively. Efficacy of herbicides in control of prevailing weeds during the 3 years field trial period was ranged of 48.5% to 100.0%. No visual alfalfa injured was determined by any rates during the experimental period, and consequently, none of the applied herbicides reduced first-harvest alfalfa yields. Alfalfa yield was markedly affected by herbicide efficacy in all experimental years, particularly in the second year, where yields of herbicide treatments were similar to that of the weed free control.

  19. Combined effects of ozone and water stress on alfalfa growth and yield. [Medicago sativa L

    Energy Technology Data Exchange (ETDEWEB)

    Temple, P.J.; Benoit, L.F.; Lennox, R.W.; Reagan, C.A.; Taylor, O.C.

    A 2-yr study (1984 and 1985) designed to determine the interactive effects of ozone (O/sub 3/) and water stress on alfalfa (Medicago sativa L. cv. WL-514) was conducted in Shafter, CA. The objectives of this study were to develop O/sub 3/ dose-yield response functions for alfalfa, to determine how water stress could alter these functions, and to describe the cumulative effects of multiple-year exposures to O/sub 3/ on this perennial crop. Field-grown alfalfa, raised under normally irrigated (NI) or water-stressed (WS) conditions in open-top chambers, was exposed to five O/sub 3/ treatments including charcoal-filtered (CF), nonfiltered (NF), and NF plus an additional 33, 67, or 100% of ambient O/sub 3/ concentrations. Ambient O/sub 3/ concentrations averaged 0.049 ..mu..L L/sup -1/ in 1984 and 0.042 ..mu..L L/sup -1/ in 1985 for the seasonal 12-h (0900-2100) means from April to October. Water stress reduced total seasonal yield about 10% in 1984 and 27% in 1985. Ozone significantly reduced yields in both years, and the interactions between O/sub 3/ and water stress was statistically significant in 1985 and for combined 1984 and 1985 years. Ozone dose-alfalfa yield loss functions were homogeneous between 1984 and 1985 and no evidence of a cumulative effect of multiple-year exposure to O/sub 3/ was found on top growth. However, crown (underground stem) weights were significantly reduced by O/sub 3/, suggesting that continued exposure to O/sub 3/ could shorten the productive life of alfalfa stands, in addition to its effect on yield.

  20. Cloning and characterization of chromosomal markers in alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Yu, Feng; Lei, Yunting; Li, Yuan; Dou, Quanwen; Wang, Haiqing; Chen, Zhiguo

    2013-07-01

    Eleven tandemly repetitive sequences were identified from a Cot-1 library by FISH and sequence analysis of alfalfa (Medicago sativa). Five repetitive sequences (MsCR-1, MsCR-2, MsCR-3, MsCR-4, and MsCR-5) were centromeric or pericentromeric, of which three were satellite DNAs and two were minisatellite DNAs. Monomers of 144, 148, and 168 bp were identified in MsCR-1, MsCR-2, and MsCR-3, respectively, while 15 and 39 bp monomers were identified in MsCR-4 and MsCR-5, respectively. Three repetitive sequences were characterized as subtelomeric; one repetitive sequence, MsTR-1, had a 184 bp monomer, and two repetitive sequences had fragments of 204 and 327 bp. Sequence analysis revealed homology (70-80 %) between MsTR-1 and a highly repeated sequence (C300) isolated from M. ssp. caerulea. Three identified repetitive sequences produced hybridization signals at multiple sites in a few of the chromosomes; one repetitive sequence was identified as the E180 satellite DNA previously isolated from M. sativa, while the other 163 and 227 bp fragments had distinct sequences. Physical mapping of the repetitive sequences with double-target FISH revealed different patterns. Thus, nine novel tandemly repetitive sequences that can be adopted as distinct chromosome markers in alfalfa were identified in this study. Furthermore, the chromosome distribution of each sequence was well described. Though significant chromosome variations were detected within and between cultivars, a molecular karyotype of alfalfa was suggested with the chromosome markers we identified. Therefore, these novel chromosome markers will still be a powerful tool for genome composition analysis, phylogenetic studies, and breeding applications.

  1. Characterization of two novel cold-inducible K3 dehydrin genes from alfalfa (Medicago sativa spp. sativa L.).

    Science.gov (United States)

    Dubé, Marie-Pier; Castonguay, Yves; Cloutier, Jean; Michaud, Josée; Bertrand, Annick

    2013-03-01

    Dehydrin defines a complex family of intrinsically disordered proteins with potential adaptive value with regard to freeze-induced cell dehydration. Search within an expressed sequence tags library from cDNAs of cold-acclimated crowns of alfalfa (Medicago sativa spp. sativa L.) identified transcripts putatively encoding K(3)-type dehydrins. Analysis of full-length coding sequences unveiled two highly homologous sequence variants, K(3)-A and K(3)-B. An increase in the frequency of genotypes yielding positive genomic amplification of the K(3)-dehydrin variants in response to selection for superior tolerance to freezing and the induction of their expression at low temperature strongly support a link with cold adaptation. The presence of multiple allelic forms within single genotypes and independent segregation indicate that the two K(3) dehydrin variants are encoded by distinct genes located at unlinked loci. The co-inheritance of the K(3)-A dehydrin with a Y(2)K(4) dehydrin restriction fragment length polymorphism with a demonstrated impact on freezing tolerance suggests the presence of a genome domain where these functionally related genes are located. These results provide additional evidence that dehydrin play important roles with regard to tolerance to subfreezing temperatures. They also underscore the value of recurrent selection to help identify variants within a large multigene family in allopolyploid species like alfalfa.

  2. SRAP polymorphisms associated with superior freezing tolerance in alfalfa (Medicago sativa spp. sativa).

    Science.gov (United States)

    Castonguay, Yves; Cloutier, Jean; Bertrand, Annick; Michaud, Réal; Laberge, Serge

    2010-05-01

    Sequence-related amplified polymorphism (SRAP) analysis was used to uncover genetic polymorphisms among alfalfa populations recurrently selected for superior tolerance to freezing (TF populations). Bulk DNA samples (45 plants/bulk) from each of the cultivar Apica (ATF0), and populations ATF2, ATF4, ATF5, and ATF6 were evaluated with 42 different SRAP primer pairs. Several polymorphisms that progressively intensified or decreased with the number of recurrent cycles were identified. Four positive polymorphisms (F10-R14, Me4-R8, F10-R8 and F11-R9) that, respectively, yielded 540-, 359-, 213-, and 180-bp fragments were selected for further analysis. SRAP amplifications with genotypes within ATF populations confirmed that the polymorphisms identified with bulk DNA samples were reflecting changes in the frequency of their occurrence in response to selection. In addition, the number of genotypes cumulating multiple polymorphisms markedly increased in response to recurrent selection. Independent segregation of the four SRAP polymorphisms suggests location at unlinked loci. Homology search gave matches with BAC clones from syntenic Medicago truncatula for the four SRAP fragments. Analysis of the relationship with low temperature tolerance showed that multiple SRAP polymorphisms are more frequent in genotypes that maintain superior regrowth after freezing. These results show that SRAP analysis of bulk DNA samples from recurrent selections is an effective approach for the identification of genetic polymorphisms associated with quantitative traits in allogamous species. These polymorphisms could be useful tools for indirect selection of freezing tolerance in alfalfa.

  3. Ractopamine up take by alfalfa (Medicago sativa) and wheat (Triticum aestivum) from soil.

    Science.gov (United States)

    Shelver, Weilin L; DeSutter, Thomas M

    2015-08-01

    Ractopamine is a beta adrenergic agonist used as a growth promoter in swine, cattle and turkeys. To test whether ractopamine has the potential to accumulate in plants grown in contaminated soil, a greenhouse study was conducted with alfalfa (Medicago sativa) and wheat (Triticum aestivum) grown in two soils having different concentrations of organic matter (1.3% and 2.1%), amended with 0, 0.5, and 10 μg/g of ractopamine. Plant growth ranged from 2.7 to 8.8 g dry weight (dw) for alfalfa, and 8.7 to 40 g dw for wheat and was generally greater in the higher organic matter content soil. The uptake of ractopamine in plant tissues ranged from non-detectable to 897 ng/g and was strongly dependent on soil ractopamine concentration across soil and plant tissue. When adjusted to the total fortified quantities, the amount of ractopamine taken up by the plant tissue was low, <0.01% for either soil.

  4. Alfalfa (Medicago sativa L.) shoot saponins: identification and bio-activity by the assessment of aphid feeding.

    Science.gov (United States)

    Mazahery-Laghab, H; Yazdi-Samadi, B; Bagheri, M; Bagheri, A R

    2011-01-01

    Biochemical components in alfalfa (Medicago sativa L.), such as saponins, can act as protecting factors against bio-stresses. Saponins are also antifeedants and show oral toxicity towards higher and lower animals. Changes in saponins, such as variation in the carbon skeleton, or hydrolysis of saponin glycosides and other conjugates, may change their biological effects. The aims of this research were to study saponin variation in different growth stages of alfalfa and to investigate the biological role of saponins in the spotted alfalfa aphid, Therioaphis maculata. Saponins from alfalfa shoots in different growth stages were extracted, chemically purified and analysed by TLC. Specific saponins such as soyasaponin1 from root and shoot and two bisdesmosides of medicagenic acid, one from shoot and another from root tissues, were identified using reference compounds allowing changes in saponin composition during plant development in different shoot tissues of alfalfa to be assessed. The response of the alfalfa aphid to feeding on alfalfa in different growth stages was studied. No significant difference in the survival of aphids, from neonate to adult, was observed, but due to the antibiotic effects of saponins, two differences were found in the onset of nymph production and cumulative nymph production. The results show that the saponin composition in alfalfa changes with plant development and this, in turn, can often negatively affect the development of specific insect pests such as the spotted alfalfa aphid, suggesting a possible biological role of alfalfa saponins.

  5. Concerted changes in N and C primary metabolism in alfalfa (Medicago sativa) under water restriction.

    Science.gov (United States)

    Aranjuelo, Iker; Tcherkez, Guillaume; Molero, Gemma; Gilard, Françoise; Avice, Jean-Christophe; Nogués, Salvador

    2013-02-01

    Although the mechanisms of nodule N(2) fixation in legumes are now well documented, some uncertainty remains on the metabolic consequences of water deficit. In most cases, little consideration is given to other organs and, therefore, the coordinated changes in metabolism in leaves, roots, and nodules are not well known. Here, the effect of water restriction on exclusively N(2)-fixing alfalfa (Medicago sativa L.) plants was investigated, and proteomic, metabolomic, and physiological analyses were carried out. It is shown that the inhibition of nitrogenase activity caused by water restriction was accompanied by concerted alterations in metabolic pathways in nodules, leaves, and roots. The data suggest that nodule metabolism and metabolic exchange between plant organs nearly reached homeostasis in asparagine synthesis and partitioning, as well as the N demand from leaves. Typically, there was (i) a stimulation of the anaplerotic pathway to sustain the provision of C skeletons for amino acid (e.g. glutamate and proline) synthesis; (ii) re-allocation of glycolytic products to alanine and serine/glycine; and (iii) subtle changes in redox metabolites suggesting the implication of a slight oxidative stress. Furthermore, water restriction caused little change in both photosynthetic efficiency and respiratory cost of N(2) fixation by nodules. In other words, the results suggest that under water stress, nodule metabolism follows a compromise between physiological imperatives (N demand, oxidative stress) and the lower input to sustain catabolism.

  6. Stem nematode counteracts plant resistance of aphids in alfalfa, Medicago sativa.

    Science.gov (United States)

    Ramirez, Ricardo A; Spears, Lori R

    2014-10-01

    Plants are exploited by a diverse community of insect herbivores and phytopathogens that interact indirectly through plant-mediated interactions. Generally, plants are thought to respond to insects and pathogens through different defensive signaling pathways. As plants are selected for resistance to one phytophagous organism type (insect vs. pathogen) in managed systems, it is not clear how this selection may affect community interactions. This study examined the effect of nematode-resistant varieties on aphid (Acyrthosiphon pisum) suppression, and then determined how infection by the stem nematode, Ditylenchus dipsaci, mediated ecological effects on aphids and on plant defense proteins. Four alfalfa (Medicago sativa) varieties were selected with resistance to nematodes only (+,-), aphids only (-,+), nematodes and aphids (+,+), and susceptibility to nematodes and aphids (-,-). Field and greenhouse experiments were conducted to isolate the effect of nematode infection and aphid abundance on each variety. We found that varieties resistant to nematode, regardless of aphid resistance, had the lowest aphid counts, suggesting possible cross-resistance. Aphid abundance, however, increased when plants were exposed to nematodes. Resistant varieties were associated with elevated saponins but these compounds were not affected by insect or pathogen feeding. Concentrations of peroxidases and trypsin inhibitors, however, were increased in nematode resistant varieties when exposed to nematodes and aphids, respectively. The patterns of plant defense were variable, and a combination of resistance traits and changes in nutrient availability may drive positive interactions between nematodes and aphids aboveground.

  7. Enhancement of lead uptake by alfalfa (Medicago sativa) using EDTA and a plant growth promoter.

    Science.gov (United States)

    López, Martha L; Peralta-Videa, Jose R; Benitez, Tenoch; Gardea-Torresdey, Jorge L

    2005-10-01

    Phytoremediation is a novel cleanup technology for the removal of contaminants from polluted waters and soils. In phytoremediation, the plant uptake capability and the availability of the pollutant in the media are important. Here we show the results of a study on the combined effects of ethylenediaminetetraacetic acid (EDTA) and the phytohormone indole-3-acetic acid (IAA) on Pb uptake by Medicago sativa (alfalfa). Plants were grown in hydroponics media containing a nutrient solution amended with Pb at 0.2mM and different combinations of EDTA, and IAA. After 10d of treatment, the Pb content in plant tissues was quantified using an Inductively Coupled Plasma Optical Emission Spectrometer (ICP/OES). The results showed that the combination of 100 microM IAA/0.2 mM EDTA increased the Pb accumulation in leaves by about 2800% and by about 600%, as compared to Pb content in leaves of plants exposed to Pb alone and those cultivated with Pb/EDTA, respectively. These results indicate that non-metal hyperaccumulator plants could increase their hyperaccumulating potential without genetic manipulation.

  8. Glyphosate-tolerant alfalfa is compositionally equivalent to conventional alfalfa (Medicago sativa L.).

    Science.gov (United States)

    McCann, Melinda C; Rogan, Glennon J; Fitzpatrick, Sharie; Trujillo, William A; Sorbet, Roy; Hartnell, Gary F; Riodan, Susan G; Nemeth, Margaret A

    2006-09-20

    Glyphosate-tolerant alfalfa (GTA) was developed to withstand over-the-top applications of glyphosate, the active ingredient in Roundup agricultural herbicides. As a part of the safety assessment, GTA (designated J101 x J163) was grown under controlled field conditions at geographically diverse locations within the United States during the 2001 and 2003 field seasons along with control and other conventional alfalfa varieties for compositional assessment. Field trials were conducted using a randomized complete block design with four replication blocks at each site. Alfalfa forage was harvested at the late bud to early bloom stage from each plot at five field sites in 2001 (establishment year) and from four field sites in 2003 (third year of stand). The concentration of proximate constituents, fibers, amino acids, coumestrol, and minerals in the forage was measured. The results showed that the forage from GTA J101 x J163 is compositionally equivalent to forage from the control and conventional alfalfa varieties.

  9. Modeling feral alfalfa (Medicago sativa subsp. sativa L.) occurrence using topographical and environmental variables

    Science.gov (United States)

    Because alfalfa is a perennial species cross pollinated by bees and can establish along roadsides and ruderal areas, there is concern that feral plants can serve as reservoirs and conduits for transgenic genes. The objective of this study was to survey feral alfalfa in alfalfa seed production areas ...

  10. Molecular Diversity and Population Structure of a Worldwide Collection of Cultivated Tetraploid Alfalfa (Medicago sativa subsp. sativa L.) Germplasm as Revealed by Microsatellite Markers.

    Science.gov (United States)

    Qiang, Haiping; Chen, Zhihong; Zhang, Zhengli; Wang, Xuemin; Gao, Hongwen; Wang, Zan

    2015-01-01

    Information on genetic diversity and population structure of a tetraploid alfalfa collection might be valuable in effective use of the genetic resources. A set of 336 worldwide genotypes of tetraploid alfalfa (Medicago sativa subsp. sativa L.) was genotyped using 85 genome-wide distributed SSR markers to reveal the genetic diversity and population structure in the alfalfa. Genetic diversity analysis identified a total of 1056 alleles across 85 marker loci. The average expected heterozygosity and polymorphism information content values were 0.677 and 0.638, respectively, showing high levels of genetic diversity in the cultivated tetraploid alfalfa germplasm. Comparison of genetic characteristics across chromosomes indicated regions of chromosomes 2 and 3 had the highest genetic diversity. A higher genetic diversity was detected in alfalfa landraces than that of wild materials and cultivars. Two populations were identified by the model-based population structure, principal coordinate and neighbor-joining analyses, corresponding to China and other parts of the world. However, lack of strictly correlation between clustering and geographic origins suggested extensive germplasm exchanges of alfalfa germplasm across diverse geographic regions. The quantitative analysis of the genetic diversity and population structure in this study could be useful for genetic and genomic analysis and utilization of the genetic variation in alfalfa breeding.

  11. Molecular Diversity and Population Structure of a Worldwide Collection of Cultivated Tetraploid Alfalfa (Medicago sativa subsp. sativa L. Germplasm as Revealed by Microsatellite Markers.

    Directory of Open Access Journals (Sweden)

    Haiping Qiang

    Full Text Available Information on genetic diversity and population structure of a tetraploid alfalfa collection might be valuable in effective use of the genetic resources. A set of 336 worldwide genotypes of tetraploid alfalfa (Medicago sativa subsp. sativa L. was genotyped using 85 genome-wide distributed SSR markers to reveal the genetic diversity and population structure in the alfalfa. Genetic diversity analysis identified a total of 1056 alleles across 85 marker loci. The average expected heterozygosity and polymorphism information content values were 0.677 and 0.638, respectively, showing high levels of genetic diversity in the cultivated tetraploid alfalfa germplasm. Comparison of genetic characteristics across chromosomes indicated regions of chromosomes 2 and 3 had the highest genetic diversity. A higher genetic diversity was detected in alfalfa landraces than that of wild materials and cultivars. Two populations were identified by the model-based population structure, principal coordinate and neighbor-joining analyses, corresponding to China and other parts of the world. However, lack of strictly correlation between clustering and geographic origins suggested extensive germplasm exchanges of alfalfa germplasm across diverse geographic regions. The quantitative analysis of the genetic diversity and population structure in this study could be useful for genetic and genomic analysis and utilization of the genetic variation in alfalfa breeding.

  12. Effects of chlorpyrifos and chlorantraniliprole on fermentation quality of alfalfa (Medicago sativa L.) silage inoculated with or without Lactobacillus plantarum LP.

    Science.gov (United States)

    Zhang, Qing; Yu, Zhu; Wang, Xianguo; Na, Risu

    2017-03-01

    The effects of pesticides and Lactobacillus plantarum (LP) on fermentation quality of alfalfa (Medicago sativa L.) silage were investigated. Chlorpyrifos and chlorantraniliprole were sprayed on the surface of alfalfa plants at 658.6 and 45.0 g active ingredient/ha, respectively. Alfalfa plants were harvested on day 5 post-application and ensiled with or without LP. Chlorpyrifos and chlorantraniliprole decreased the yeast count of alfalfa material (P alfalfa silage (P alfalfa silage treated with pesticides (P alfalfa silage (P alfalfa silage and affected the fermentation process, whereas LP improved the fermentation quality of pesticides-contaminated alfalfa silage and slowed down the dissipation of chlorpyrifos.

  13. Effect of UV-C on Drought Tolerance of Alfalfa (Medicago sativa) Callus

    OpenAIRE

    Ali A. Ehsanpour; Roya Razavizadeh

    2005-01-01

    Water stress and unfavorable climate decrease the growth and development of plant globally. Medicago is a valuable plant as a source of food for animal, foliage and for medicine. Since, Iran is located in a dry area; consequently, the study of plant responses to water stress is important. In this research UV-C radiation was used to induce physiological and genetic changes in alfalfa callus. In vitro grown calluses of M. sativa were exposed to UV-C for 0, 15, 30 and 60 min and then, were trans...

  14. In vitro and in vivo antioxidant activity of alfalfa (Medicago sativa L.) on carbon tetrachloride intoxicated rats.

    Science.gov (United States)

    Al-Dosari, Mohammed S

    2012-01-01

    The present study was conducted to determine whether lyophilized aqueous extract of alfalfa, or Medicago sativa L. could exert antioxidant activity against carbon tetrachloride-induced oxidative stress and liver injury in rats. The hepatoprotective activity of alfalfa extract was determined by assessing the levels of serum transaminases, ALP, bilirubin and lipid profile. Further, the effect of the test substance on malondialdehyde (MDA), an end product of lipid peroxidation; antioxidant liver enzyme non-protein sulfhydryl (NP-SH); and total protein (TP) were also studied. Serum transaminase, ALP, bilirubin level, lipid profile and liver MDA were significantly elevated and the antioxidant status in liver NP-SH and TP contents were declined in animals treated with CCl (4) alone. Pretreatment with alfalfa and silymarin for three weeks prior to the administration of CCl (4) significantly prevented the increase in the serum levels of hepatic marker, LDL, VLDL levels enzymes and reduced oxidative stress indicated by elevated NP-SH and TP concentration. The histopathological examination of the livers also showed that the alfalfa extract reduced the incidence of liver lesions induced by CCl (4). The in vitro antioxidant assessment of alfalfa extract on DPPH and carotene-linoleic assays demonstrated a moderate antioxidant potential. Results suggest that the alfalfa extract possesses hepatoprotective and antioxidative stress properties possibly through its antioxidant phytochemical constituents and substantiates its use in various liver disorders as a hepatoprotector.

  15. Paenibacillus medicaginis sp. nov. a chitinolytic endophyte isolated from the root nodule of alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Lai, Wei-An; Hameed, Asif; Lin, Shih-Yao; Hung, Mei-Hua; Hsu, Yi-Han; Liu, You-Cheng; Shahina, Mariyan; Shen, Fo-Ting; Young, Chiu-Chung

    2015-08-04

    A Gram-stain-variable, short-rod-shaped, endospore-forming, strictly aerobic, non-motile, chitinolytic and endophytic bacterium, designated strain CC-Alfalfa-19T, exhibiting unusual bipolar appendages was isolated from the root nodule of alfalfa (Medicago sativa L.) in Taiwan and subjected to a polyphasic taxonomy. Based on 16S rRNA gene sequence analysis, strain CC-Alfalfa-19T was found to be most closely related to Paenibacillus puldeungensis CAU 9324T (95.2 %), whereas other Paenibacillus species shared ≤95.0 % sequence similarity. The phylogenetic analysis revealed a distinct phyletic lineage established by strain CC-Alfalfa-19T with respect to other Paenibacillus species. Fatty acids comprised predominantly anteiso-C15:0, C16:0, anteiso-C17:0 and iso-C16. Menaquinone 7 (MK-7) was identified as the sole respiratory quinone and the genomic DNA G+C content was 42.7 mol%. Polar lipids included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine, an unidentified glycolipid and an unidentified lipid. The diagnostic diamino acid found in the cell-wall peptidoglycan was meso-diaminopimelic acid. Based on the polyphasic taxonomic evidences that were in line with the genus Paenibacillus and additional distinguishing characteristics, strain CC-Alfalfa-19T is considered to represent a novel species, for which the name Paenibacillus medicaginis sp. nov. (type strain CC-Alfalfa-19T = BCRC 80441T = JCM 18446T) is proposed.

  16. Speciation Matters: Bioavailability of Silver and Silver Sulfide Nanoparticles to Alfalfa (Medicago sativa).

    Science.gov (United States)

    Stegemeier, John P; Schwab, Fabienne; Colman, Benjamin P; Webb, Samuel M; Newville, Matthew; Lanzirotti, Antonio; Winkler, Christopher; Wiesner, Mark R; Lowry, Gregory V

    2015-07-21

    Terrestrial crops are directly exposed to silver nanoparticles (Ag-NPs) and their environmentally transformed analog silver sulfide nanoparticles (Ag2S-NPs) when wastewater treatment biosolids are applied as fertilizer to agricultural soils. This leads to a need to understand their bioavailability to plants. In the present study, the mechanisms of uptake and distribution of silver in alfalfa (Medicago sativa) were quantified and visualized upon hydroponic exposure to Ag-NPs, Ag2S-NPs, and AgNO3 at 3 mg total Ag/L. Total silver uptake was measured in dried roots and shoots, and the spatial distribution of elements was investigated using transmission electron microscopy (TEM) and synchrotron-based X-ray imaging techniques. Despite large differences in release of Ag(+) ions from the particles, Ag-NPs, Ag2S-NPs, and Ag(+) became associated with plant roots to a similar degree, and exhibited similarly limited (<1%) amounts of translocation of silver into the shoot system. X-ray fluorescence (XRF) mapping revealed differences in the distribution of Ag into roots for each treatment. Silver nanoparticles mainly accumulated in the (columella) border cells and elongation zone, whereas Ag(+) accumulated more uniformly throughout the root. In contrast, Ag2S-NPs remained largely adhered to the root exterior, and the presence of cytoplasmic nano-SixOy aggregates was observed. Exclusively in roots exposed to particulate silver, NPs smaller than the originally dosed NPs were identified by TEM in the cell walls. The apparent accumulation of Ag in the root apoplast determined by XRF, and the presence of small NPs in root cell walls suggests uptake of partially dissolved NPs and translocation along the apoplast.

  17. A saturated genetic linkage map of autotetraploid alfalfa (Medicago sativa L.) developed using genotyping-by-sequencing is highly syntenous with the Medicago truncatula genome.

    Science.gov (United States)

    Li, Xuehui; Wei, Yanling; Acharya, Ananta; Jiang, Qingzhen; Kang, Junmei; Brummer, E Charles

    2014-08-21

    A genetic linkage map is a valuable tool for quantitative trait locus mapping, map-based gene cloning, comparative mapping, and whole-genome assembly. Alfalfa, one of the most important forage crops in the world, is autotetraploid, allogamous, and highly heterozygous, characteristics that have impeded the construction of a high-density linkage map using traditional genetic marker systems. Using genotyping-by-sequencing (GBS), we constructed low-cost, reasonably high-density linkage maps for both maternal and paternal parental genomes of an autotetraploid alfalfa F1 population. The resulting maps contain 3591 single-nucleotide polymorphism markers on 64 linkage groups across both parents, with an average density of one marker per 1.5 and 1.0 cM for the maternal and paternal haplotype maps, respectively. Chromosome assignments were made based on homology of markers to the M. truncatula genome. Four linkage groups representing the four haplotypes of each alfalfa chromosome were assigned to each of the eight Medicago chromosomes in both the maternal and paternal parents. The alfalfa linkage groups were highly syntenous with M. truncatula, and clearly identified the known translocation between Chromosomes 4 and 8. In addition, a small inversion on Chromosome 1 was identified between M. truncatula and M. sativa. GBS enabled us to develop a saturated linkage map for alfalfa that greatly improved genome coverage relative to previous maps and that will facilitate investigation of genome structure. GBS could be used in breeding populations to accelerate molecular breeding in alfalfa.

  18. Identification of molecular markers associated with Verticillium wilt resistance in alfalfa (Medicago sativa L. using high-resolution melting.

    Directory of Open Access Journals (Sweden)

    Tiejun Zhang

    Full Text Available Verticillium wilt, caused by the soilborne fungus, Verticillium alfalfae, is one of the most serious diseases of alfalfa (Medicago sativa L. worldwide. To identify loci associated with resistance to Verticillium wilt, a bulk segregant analysis was conducted in susceptible or resistant pools constructed from 13 synthetic alfalfa populations, followed by association mapping in two F1 populations consisted of 352 individuals. Simple sequence repeat (SSR and single nucleotide polymorphism (SNP markers were used for genotyping. Phenotyping was done by manual inoculation of the pathogen to replicated cloned plants of each individual and disease severity was scored using a standard scale. Marker-trait association was analyzed by TASSEL. Seventeen SNP markers significantly associated with Verticillium wilt resistance were identified and they were located on chromosomes 1, 2, 4, 7 and 8. SNP markers identified on chromosomes 2, 4 and 7 co-locate with regions of Verticillium wilt resistance loci reported in M. truncatula. Additional markers identified on chromosomes 1 and 8 located the regions where no Verticillium resistance locus has been reported. This study highlights the value of SNP genotyping by high resolution melting to identify the disease resistance loci in tetraploid alfalfa. With further validation, the markers identified in this study could be used for improving resistance to Verticillium wilt in alfalfa breeding programs.

  19. Identification of molecular markers associated with Verticillium wilt resistance in alfalfa (Medicago sativa L.) using high-resolution melting.

    Science.gov (United States)

    Zhang, Tiejun; Yu, Long-Xi; McCord, Per; Miller, David; Bhamidimarri, Suresh; Johnson, David; Monteros, Maria J; Ho, Julie; Reisen, Peter; Samac, Deborah A

    2014-01-01

    Verticillium wilt, caused by the soilborne fungus, Verticillium alfalfae, is one of the most serious diseases of alfalfa (Medicago sativa L.) worldwide. To identify loci associated with resistance to Verticillium wilt, a bulk segregant analysis was conducted in susceptible or resistant pools constructed from 13 synthetic alfalfa populations, followed by association mapping in two F1 populations consisted of 352 individuals. Simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers were used for genotyping. Phenotyping was done by manual inoculation of the pathogen to replicated cloned plants of each individual and disease severity was scored using a standard scale. Marker-trait association was analyzed by TASSEL. Seventeen SNP markers significantly associated with Verticillium wilt resistance were identified and they were located on chromosomes 1, 2, 4, 7 and 8. SNP markers identified on chromosomes 2, 4 and 7 co-locate with regions of Verticillium wilt resistance loci reported in M. truncatula. Additional markers identified on chromosomes 1 and 8 located the regions where no Verticillium resistance locus has been reported. This study highlights the value of SNP genotyping by high resolution melting to identify the disease resistance loci in tetraploid alfalfa. With further validation, the markers identified in this study could be used for improving resistance to Verticillium wilt in alfalfa breeding programs.

  20. Resistance and susceptibility of alfalfa (Medicago sativa L.) cultivars to the aphid Therioaphis maculata (Homoptera:Aphididae): insect biology and cultivar evaluation

    Institute of Scientific and Technical Information of China (English)

    ALEXANDRE DE ALMEIDA E SILVA; ELENICE MOURO VARANDA; JOS(E) RICARDO BAROSELA

    2006-01-01

    Biology of the aphid Therioaphis maculata was studied on alfalfa (Medicago sativa L.), including four resistant (Mesa-Sirsa, CUF101, Baker and Lahontan) and two susceptible (ARC and Caliverde) alfalfa cultivars, and one of the most cropped Brazilian cultivars, Crioula. Under controlled conditions, antibiosis (i.e., reduced longevity, fecundity and increased mortality of the aphid) was observed mainly on the resistant alfalfa cultivars,except on Lahontan. Crioula seemed to be tolerant to aphids. Present data support geographic limitation usage of cultivars, and we suggest Baker and Mesa-Sirsa as sources of antibiosis,and provide biological information of a tropical T. maculata biotype on alfalfa.

  1. In vivo characterization of the effects of abscisic acid and drying protocols associated with the acquisition of desiccation tolerance in alfalfa (Medicago sativa L.) somatic embryos

    NARCIS (Netherlands)

    Sreedhar, L.; Wolkers, W.F.; Hoekstra, F.A.; Bewley, J.D.

    2002-01-01

    Although somatic embryos of alfalfa (Medicago sativa L.) had acquired some tolerance to desiccation at the cotyledonary stage of development (22 d after plating), additional culturing in 20 ?M abscisic acid (ABA) for 8 d induced greater desiccation tolerance, as determined by increased germination.

  2. Co-transforming bar and CsALDH Genes Enhanced Resistance to Herbicide and Drought and Salt Stress in Transgenic Alfalfa (Medicago sativa L.)

    OpenAIRE

    Duan, Zhen; Zhang, Daiyu; Zhang, Jianquan; Di, Hongyan; Wu, Fan; Hu, Xiaowen; Meng, Xuanchen; Luo, Kai; Zhang, Jiyu; Wang, Yanrong

    2015-01-01

    Drought and high salinity are two major abiotic factors that restrict the productivity of alfalfa. By application of the Agrobacterium-mediated transformation method, an oxidative responsive gene, CsALDH12A1, from the desert grass Cleistogenes songorica together with the bar gene associated with herbicide resistance, were co-transformed into alfalfa (Medicago sativa L.). From the all 90 transformants, 16 were positive as screened by spraying 1 mL L-1 10% Basta solution and molecularly diagnos...

  3. The succinoglycan endoglycanase encoded by exoK is required for efficient symbiosis of Sinorhizobium meliloti 1021 with the host plants Medicago truncatula and Medicago sativa (Alfalfa).

    Science.gov (United States)

    Mendis, Hajeewaka C; Queiroux, Clothilde; Brewer, Tess E; Davis, Olivia M; Washburn, Brian K; Jones, Kathryn M

    2013-09-01

    The acidic polysaccharide succinoglycan produced by the nitrogen-fixing rhizobial symbiont Sinorhizobium meliloti 1021 is required for this bacterium to invade the host plant Medicago truncatula and to efficiently invade the host plant M. sativa (alfalfa). The β-glucanase enzyme encoded by exoK has previously been demonstrated to cleave succinoglycan and participate in producing the low molecular weight form of this polysaccharide. Here, we show that exoK is required for efficient S. meliloti invasion of both M. truncatula and alfalfa. Deletion mutants of exoK have a substantial reduction in symbiotic productivity on both of these plant hosts. Insertion mutants of exoK have an even less productive symbiosis than the deletion mutants with the host M. truncatula that is caused by a secondary effect of the insertion itself, and may be due to a polar effect on the expression of the downstream exoLAMON genes.

  4. Genome-Wide Association Mapping and Genomic Selection for Alfalfa (Medicago sativa) Forage Quality Traits

    Science.gov (United States)

    Pecetti, Luciano; Brummer, E. Charles; Palmonari, Alberto; Tava, Aldo

    2017-01-01

    Genetic progress for forage quality has been poor in alfalfa (Medicago sativa L.), the most-grown forage legume worldwide. This study aimed at exploring opportunities for marker-assisted selection (MAS) and genomic selection of forage quality traits based on breeding values of parent plants. Some 154 genotypes from a broadly-based reference population were genotyped by genotyping-by-sequencing (GBS), and phenotyped for leaf-to-stem ratio, leaf and stem contents of protein, neutral detergent fiber (NDF) and acid detergent lignin (ADL), and leaf and stem NDF digestibility after 24 hours (NDFD), of their dense-planted half-sib progenies in three growing conditions (summer harvest, full irrigation; summer harvest, suspended irrigation; autumn harvest). Trait-marker analyses were performed on progeny values averaged over conditions, owing to modest germplasm × condition interaction. Genomic selection exploited 11,450 polymorphic SNP markers, whereas a subset of 8,494 M. truncatula-aligned markers were used for a genome-wide association study (GWAS). GWAS confirmed the polygenic control of quality traits and, in agreement with phenotypic correlations, indicated substantially different genetic control of a given trait in stems and leaves. It detected several SNPs in different annotated genes that were highly linked to stem protein content. Also, it identified a small genomic region on chromosome 8 with high concentration of annotated genes associated with leaf ADL, including one gene probably involved in the lignin pathway. Three genomic selection models, i.e., Ridge-regression BLUP, Bayes B and Bayesian Lasso, displayed similar prediction accuracy, whereas SVR-lin was less accurate. Accuracy values were moderate (0.3–0.4) for stem NDFD and leaf protein content, modest for leaf ADL and NDFD, and low to very low for the other traits. Along with previous results for the same germplasm set, this study indicates that GBS data can be exploited to improve both quality traits

  5. Salicornia europaea L. Na⁺/H⁺ antiporter gene improves salt tolerance in transgenic alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Zhang, L Q; Niu, Y D; Huridu, H; Hao, J F; Qi, Z; Hasi, A

    2014-07-24

    In order to obtain a salt-tolerant perennial alfalfa (Medicago sativa L.), we transferred the halophyte Salicornia europaea L. Na(+)/H(+) antiporter gene, SeNHX1, to alfalfa by using the Agrobacterium-mediated transformation method. The transformants were confirmed by both PCR and RT-PCR analyses. Of 197 plants that were obtained after transformation, 36 were positive by PCR analysis using 2 primer pairs for the CaMV35S-SeNHX1 and SeNHX1-Nos fragments; 6 plants survived in a greenhouse. RT-PCR analysis revealed that SeNHX1 was expressed in 5 plants. The resultant transgenic alfalfa had better salt tolerance. After stress treatment for 21 days with 0.6% NaCl, the chlorophyll and MDA contents in transgenic plants were lower, but proline content and SOD, POD, and CAT activities were higher than those in wild-type plants. These results suggest that the salt tolerance of transgenic alfalfa was improved by the overexpression of the SeNHX1 gene.

  6. Cytotoxicity and apoptosis induced by alfalfa (Medicago sativa) leaf extracts in sensitive and multidrug-resistant tumor cells.

    Science.gov (United States)

    Gatouillat, Grégory; Magid, Abdulmagid Alabdul; Bertin, Eric; Okiemy-Akeli, Marie-Genevieve; Morjani, Hamid; Lavaud, Catherine; Madoulet, Claudie

    2014-01-01

    Alfalfa (Medicago sativa) has been used to cure a wide variety of ailments. However, only a few studies have reported its anticancer effects. In this study, extracts were obtained from alfalfa leaves and their cytotoxic effects were assessed on several sensitive and multidrug-resistant tumor cells lines. Using the mouse leukaemia P388 cell line and its doxorubicin-resistant counterpart (P388/DOX), we showed that the inhibition of cell growth induced by alfalfa leaf extracts was mediated through the induction of apoptosis, as evidenced by DNA fragmentation analysis. The execution of programmed cell death was achieved via the activation of caspase-3, leading to PARP cleavage. Fractionation of toluene extract (To-1), the most active extract obtained from crude extract, led to the identification of 3 terpene derivatives and 5 flavonoids. Among them, (-)-medicarpin, (-)-melilotocarpan E, millepurpan, tricin, and chrysoeriol showed cytotoxic effects in P388 as well as P388/DOX cells. These results demonstrate that alfalfa leaf extract may have interesting potential in cancer chemoprevention and therapy.

  7. Molecular cloning and functional analysis of the drought tolerance gene MsHSP70 from alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Li, Zhenyi; Long, Ruicai; Zhang, Tiejun; Wang, Zhen; Zhang, Fan; Yang, Qingchuan; Kang, Junmei; Sun, Yan

    2017-03-01

    Heat shock proteins (HSPs) are a ubiquitously expressed class of protective proteins that play a key role in plant response to stressful conditions. This study aimed to characterize and investigate the function of an HSP gene in alfalfa (Medicago sativa). MsHSP70, which contains a 2028-bp open reading frame, was identified through homology cloning. MsHSP70 shares high sequence identity (94.47%) with HSP70 from Medicago truncatula. Expression analysis of MsHSP70 in alfalfa organs revealed a relatively higher expression level in aerial organs such as flowers, stems and leaves than in roots. MsHSP70 was induced by heat shock, abscisic acid (ABA) and hydrogen peroxide. Transgenic Arabidopsis seedlings overexpressing MsHSP70 were hyposensitive to polyethylene glycol (PEG) and ABA treatments, suggesting that exogenous expression of MsHSP70 enhanced Arabidopsis tolerance to these stresses. Examination of physiological indexes related to drought and ABA stress demonstrated that in comparison with non-transgenic plants, T3 transgenic Arabidopsis plants had an increased proline content, higher superoxide dismutase (SOD) activity, and decreased malondialdehyde (MDA) content. Furthermore, higher relative water content (RWC) was detected in transgenic plants compared with non-transgenic plants under drought stress. These findings clearly indicate that molecular manipulation of MsHSP70 in plants can have substantial effects on stress tolerance.

  8. Identification of transcriptome involved in atrazine detoxification and degradation in alfalfa (Medicago sativa) exposed to realistic environmental contamination.

    Science.gov (United States)

    Zhang, Jing Jing; Lu, Yi Chen; Zhang, Shu Hao; Lu, Feng Fan; Yang, Hong

    2016-08-01

    Plants are constantly exposed to a variety of toxic compounds (or xenobiotics) such as pesticides (or herbicides). Atrazine (ATZ) as herbicide has become one of the environmental contaminants due to its intensive use during crop production. Plants have evolved strategies to cope with the adverse impact of ATZ. However, the mechanism for ATZ degradation and detoxification in plants is largely unknown. Here we employed a global RNA-sequencing (RNA-Seq) strategy to dissect transcriptome variation in alfalfa (Medicago sativa) exposed to ATZ. Four libraries were constructed including Root-ATZ (root control, ATZ-free), Shoot-ATZ, Root+ATZ (root treated with ATZ) and Shoot+ATZ. Hierarchical clustering was performed to display the expression patterns for all differentially expressed genes (DEGs) under ATZ exposure. Transcripts involved in ATZ detoxification, stress responses (e.g. oxidation and reduction, conjugation and hydrolytic reactions), and regulations of cysteine biosynthesis were identified. Several genes encoding glycosyltransferases, glutathione S-transferases or ABC transporters were up-regulated notably. Also, many other genes involved in oxidation-reduction, conjugation, and hydrolysis for herbicide degradation were differentially expressed. These results suggest that ATZ in alfalfa can be detoxified or degraded through different pathways. The expression patterns of some DEGs by high-throughput sequencing were well confirmed by qRT-PCR. Our results not only highlight the transcriptional complexity in alfalfa exposed to ATZ but represent a major improvement for analyzing transcriptional changes on a large scale as well.

  9. Manejo de água para estabelecimento de alfafa (Medicago sativa L. Water management for alfalfa (Medicago sativa L. establishment

    Directory of Open Access Journals (Sweden)

    Joaquim Bartolomeu Rassini

    2001-04-01

    Full Text Available O manejo de água para o desenvolvimento da alfafa cv. Crioula foi avaliado a campo, com a finalidade de verificar seus efeitos no estabelecimento da planta, até o 1º corte, em 1997. Para isso, verificou-se o comportamento em três estádios de desenvolvimento (E1 = início do estádio vegetativo, E2 = vegetativo pleno e E3 = reprodutivo até colheita em quatro níveis de água (A = 100%, B = 80%, C = 45-50% e D = 20-25% de uma lâmina de irrigação por aspersão. Foram avaliados oito experimentos: 111, 110, 100, 101, 001, 011, 010, 000, em que o primeiro dígito se refere a E1; o segundo, a E2; e o terceiro, a E3. O valor 0 representa a época em que o estádio não recebeu água, coberto por uma estrututura móvel, que deslizava sobre trilhos, e também protegia contra precipitações pluviais casuais. O valor 1 refere-se à época em que houve aplicação dos níveis de água de irrigação. Os estádios de desenvolvimento da planta, em termos de rendimento de matéria seca, responderam de maneira diferente às condições hídricas, sendo E2 e E3 (planta estabelecida os mais sensíveis e E1 (início do estádio vegetativo, o menos sensível, no qual a água foi prejudicial ao estabelecimento e rendimento da planta.The water management for growth of Crioula alfalfa cultivar was evaluated in a field study, in order to assess the effects in the plant establishment up to the first cut, at 1977. The study was carried out in 1997. So that, the behaviour at three growth stages (E1 = early vegetative stage, E2 = full vegetative stage, and E3 = reproductive stage until harvest in the presence of four water levels (A = 100%, B = 80%, C = 45-50%, and D = 20-25% from a sprinkler irrigation was studied. Eight combinations were evaluated: 111, 110, 100, 101, 001, 011, 010, 000, where the first digit is E1, the second is E2 and the third is E3. The number 0 in the figures represents the period in which growth stage did not receive water, cover by a

  10. Fixed-precision sequential sampling plans for estimating alfalfa caterpillar, Colias lesbia, egg density in alfalfa, Medicago sativa, fields in Córdoba, Argentina.

    Science.gov (United States)

    Serra, Gerardo V; Porta, Norma C La; Avalos, Susana; Mazzuferi, Vilma

    2013-01-01

    The alfalfa caterpillar, Colias lesbia (Fabricius) (Lepidoptera: Pieridae), is a major pest of alfalfa, Medicago sativa L. (Fabales: Fabaceae), crops in Argentina. Its management is based mainly on chemical control of larvae whenever the larvae exceed the action threshold. To develop and validate fixed-precision sequential sampling plans, an intensive sampling programme for C. lesbia eggs was carried out in two alfalfa plots located in the Province of Córdoba, Argentina, from 1999 to 2002. Using Resampling for Validation of Sampling Plans software, 12 additional independent data sets were used to validate the sequential sampling plan with precision levels of 0.10 and 0.25 (SE/mean), respectively. For a range of mean densities of 0.10 to 8.35 eggs/sample, an average sample size of only 27 and 26 sample units was required to achieve a desired precision level of 0.25 for the sampling plans of Green and Kuno, respectively. As the precision level was increased to 0.10, average sample size increased to 161 and 157 sample units for the sampling plans of Green and Kuno, respectively. We recommend using Green's sequential sampling plan because it is less sensitive to changes in egg density. These sampling plans are a valuable tool for researchers to study population dynamics and to evaluate integrated pest management strategies.

  11. Regulation of symbiotic nitrogen fixation in root nodules of alfalfa (Medicago sativa) infected with Rhizobium meliloti.

    Science.gov (United States)

    Kamberger, W

    1977-10-24

    Symbiotic nitrogen fixation of Rhizobium meliloti bacteroids in Medicago sativa root nodules was suppressed by several inorganic nitrogen sources. Amino acids like glutamine, glutamic acid and aspartic acid, which can serve as sole nitrogen sources for the unnodulated plant did not influence nitrogenase activity of effective nodules, even at high concetrations. Ammonia and nitrate suppressed symbiotic nitrogen fixation in vivo only at concentrations much higher than those needed for suppression of nitrogenase activity in free living nitrogen fixing bacteria. The kinetics of suppression were slow compared with that of free living nitrogen fixing bacteria. On the other hand, nitrite, which acts as a direct inhibitor of nitrogenase, suppressed very quickly and at low concentrations. Glutamic acid and glutamine enhanced the effect of ammonia dramatically, while the suppression by nitrate was enhanced only slightly.

  12. In vivo Characterization of the Effects of Abscisic Acid and Drying Protocols Associated with the Acquisition of Desiccation Tolerance in Alfalfa (Medicago sativa L.) Somatic Embryos

    OpenAIRE

    SREEDHAR, LEKHA; Wolkers, Willem F.; Hoekstra, Folkert A.; BEWLEY, J. DEREK

    2002-01-01

    Although somatic embryos of alfalfa (Medicago sativa L.) had acquired some tolerance to desiccation at the cotyledonary stage of development (22 d after plating), additional culturing in 20 μm abscisic acid (ABA) for 8 d induced greater desiccation tolerance, as determined by increased germination. Compared with fast drying, slow drying of the ABA‐treated embryos improved desiccation tolerance. However, slow drying of non‐ABA‐treated embryos led to the complete loss of germination capacity, w...

  13. The Effect of Priming on Germination and Seedling Growth of Alfalfa (Medicago sativa L. under Salinity Stress

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    Jorjandi M.

    2012-08-01

    Full Text Available Salinity stress is an abiotic stress which has harmful effects on germination, growth and yield of alfalfa (Medicago sativa L. in many parts of the world. Seed priming is a way of increasing salt tolerance of plants. In this study, the effect of seed priming on germination and growth of alfalfa seedlings, Bami cultivar, under salinity condition was investigated. According to germination percentage of seeds under In vitro conditions, salicylic acid, Vitamin B12 and distilled water were selected as primes under salinities of 0, 5 and 10 ds.m-2 NaCl solution for further studies. These studies were carried out in a factorial experiment based on Completely Randomized Design (CRD with three replications in greenhouse under controlled condition (25°C in day/night. Parameters like percentage and rate of germination, dry and fresh weight of seedling and leaf number were measured. Based on our research All of the treatments (priming, salinity and the interaction of priming with salinity significantly (p<0.01 affected Hypocotyl length and radicle length and in low level of salt (0 ds.m2 germination and seedling growth indexes enhanced and also with applying salicylic acid both hypocotyl and radicle lengths improved.

  14. Effects of compost organic amendments on chemical composition and in vitro digestibility of alfalfa (Medicago sativa L.

    Directory of Open Access Journals (Sweden)

    Francesco Montemurro

    2010-01-01

    Full Text Available The following fertiliser treatments were compared during the years 2002 and 2003 on alfalfa forage (Medicago sativa L.: compost obtained from the organic fraction of the Municipal Solid Waste (MSW; olive pomace compost (OPC; mineral fertiliser (Min. All the treatments allowed a distribution of 75kg ha-1 of P2O5. Three cuttings occurred: at 168, 206 and 351 days after compost application (DAA in 2002; 119, 152 and 320 DAA in 2003. Cumulative biomass and dry matter yields were measured during each experimental year. Furthermore, chemical composition and in vitro digestibility of dry matter (DMd, organic matter (OMd, crude protein (CPd and NDF (NDFd were determined. MSW treatment showed a significantly (P<0.01 higher content of ADL than OPC and Min (77.0, 66.0 and 65.0g kg-1 DM, respectively. Fertiliser treatments also affected (P<0.01 digestibility parameters. In fact, DMd and OMd values showed the same trend with lower percentages in MSW treatment than in the OPC and Min ones. The NDFd differed in all treatments having the highest value in OPC (40.1%. The results indicated that the soil distribution of organic materials offer the possibility to reduce the application of mineral fertilisers and production costs without decreasing alfalfa yield, forage chemical composition and in vitro digestibility.

  15. Soil bulk electrical resistivity and forage ground cover: nonlinear models in an alfalfa (Medicago sativa L. case study

    Directory of Open Access Journals (Sweden)

    Roberta Rossi

    2015-12-01

    Full Text Available Alfalfa is a highly productive and fertility-building forage crop; its performance, can be highly variable as influenced by within-field soil spatial variability. Characterising the relations between soil and forage- variation is important for optimal management. The aim of this work was to model the relationship between soil electrical resistivity (ER and plant productivity in an alfalfa (Medicago sativa L. field in Southern Italy. ER mapping was accomplished by a multi-depth automatic resistivity profiler. Plant productivity was assessed through normalised difference vegetation index (NDVI at 2 dates. A non-linear relationship between NDVI and deep soil ER was modelled within the framework of generalised additive models. The best model explained 70% of the total variability. Soil profiles at six locations selected along a gradient of ER showed differences related to texture (ranging from clay to sandy-clay loam, gravel content (0 to 55% and to the presence of a petrocalcic horizon. Our results prove that multi-depth ER can be used to localise permanent soil features that drive plant productivity.

  16. Low-fiber alfalfa (Medicago sativa L.) meal in the laying hen diet: effects on productive traits and egg quality.

    Science.gov (United States)

    Laudadio, V; Ceci, E; Lastella, N M B; Introna, M; Tufarelli, V

    2014-07-01

    This study was designed to determine the effects on laying performance and egg quality resulting from partial substitution of soybean meal (SBM) with low-fiber alfalfa (LFA; Medicago sativa L.) meal in the diet of early-phase laying hens. ISA Brown layers, 18 wk of age, were randomly allocated to 2 dietary treatments and fed for 10 wk. The hens were fed 2 wheat middling-based diets: a control diet, which contained SBM (15% of diet), and a test diet containing LFA (15% of diet) as the main protein source. Low-fiber alfalfa meal was obtained by a combination of sieving and air-classification processes. Feed intake was recorded daily, and egg production was calculated on a hen-day basis; eggs from each group were weekly collected to evaluate egg components and quality. The partial substitution of SBM with LFA had no adverse effect on growth performance of early-phase laying hens. Egg production and none of the egg-quality traits examined were influenced by dietary treatment, except for yolk color (P hens fed the LFA diet. Including LFA increased serum β-carotene and reduced serum cholesterol concentrations (P laying-hen diet can positively influence yolk quality without adversely affecting productive traits.

  17. Molecular cloning and characterization of a gene regulating flowering time from Alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Zhang, Tiejun; Chao, Yuehui; Kang, Junmei; Ding, Wang; Yang, Qingchuan

    2013-07-01

    Genes that regulate flowering time play crucial roles in plant development and biomass formation. Based on the cDNA sequence of Medicago truncatula (accession no. AY690425), the LFY gene of alfalfa was cloned. Sequence similarity analysis revealed high homology with FLO/LFY family genes of other plants. When fused to the green fluorescent protein, MsLFY protein was localized in the nucleus of onion (Allium cepa L.) epidermal cells. The RT-qPCR analysis of MsLFY expression patterns showed that the expression of MsLFY gene was at a low level in roots, stems, leaves and pods, and the expression level in floral buds was the highest. The expression of MsLFY was induced by GA3 and long photoperiod. Plant expression vector was constructed and transformed into Arabidopsis by the agrobacterium-mediated methods. PCR amplification with the transgenic Arabidopsis genome DNA indicated that MsLFY gene had integrated in Arabidopsis genome. Overexpression of MsLFY specifically caused early flowering under long day conditions compared with non-transgenic plants. These results indicated MsLFY played roles in promoting flowering time.

  18. Cloning and characterization of a heme oxygenase-2 gene from alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Fu, Guang-Qing; Jin, Qi-Jiang; Lin, Yu-Ting; Feng, Jian-Fei; Nie, Li; Shen, Wen-Biao; Zheng, Tian-Qing

    2011-11-01

    Heme oxygenase (HO, EC 1.14.99.3) catalyzes the oxidation of heme and performs vital roles in plant development and stress responses. Two HO isozymes exist in plants. Between these, HO-1 is an oxidative stress-response protein, and HO-2 usually exhibited constitutive expression. Although alfalfa HO-1 gene (MsHO1) has been investigated previously, HO2 is still poorly understood. In this study, we report the cloning and characterization of HO2 gene, MsHO2, from alfalfa (Medica sativa L.). The full-length cDNA of MsHO2 contains an ORF of 870 bp and encodes for 290 amino acid residues with a predicted molecular mass of 33.3 kDa. Similar to MsHO1, MsHO2 also appears to have an N-terminal transit peptide sequence for chloroplast import. Many conserved residues in plant HO were also conserved in MsHO2. However, unlike HO-1, the conserved histidine (His) required for heme-iron binding and HO activity was replaced by tyrosine (Tyr) in MsHO2. Further biochemical activity analysis of purified mature MsHO2 showed no HO activity, suggesting that MsHO2 may not be a true HO in nature. Semi-quantitative RT-PCR confirmed its maximum expression in the germinating seeds. Importantly, the expression levels of MsHO2 were up-regulated under sodium nitroprusside (SNP) and H(2)O(2) (especially) treatment, respectively.

  19. The thiol compounds glutathione and homoglutathione differentially affect cell development in alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Pasternak, Taras; Asard, Han; Potters, Geert; Jansen, Marcel A K

    2014-01-01

    Glutathione (GSH) is an important scavenger of Reactive Oxygen Species (ROS), precursor of metal chelating phytochelatins, xenobiotic defence compound and regulator of cell proliferation. Homoglutathione (hGSH) is a GSH homologue that is present in several taxa in the family of Fabaceae. It is thought that hGSH performs many of the stress-defence roles typically ascribed to GSH, yet little is known about the potential involvement of hGSH in controlling cell proliferation. Here we show that hGSH/GSH ratios vary across organs and cells and that these changes in hGSH/GSH ratio occur during dedifferentiation and/or cell cycle activation events. The use of a GSH/hGSH biosynthesis inhibitor resulted in impaired cytokinesis in isolated protoplasts, showing the critical importance of these thiol-compounds for cell division. However, exposure of isolated protoplasts to exogenous GSH accelerated cytokinesis, while exogenous hGSH was found to inhibit the same process. We conclude that GSH and hGSH have distinct functional roles in cell cycle regulation in Medicago sativa L. GSH is associated with meristemic cells, and promotes cell cycle activation and induction of somatic embryogenesis, while hGSH is associated with differentiated cells and embryo proliferation.

  20. [Simulation on the restoration effect of soil moisture in alfalfa (Medicago sativa)-grain rotation system in semi-arid and drought-prone regions of Loess Plateau].

    Science.gov (United States)

    Wang, Xue-Chun; Li, Jun; Fang, Xin-Yu; Sun, Jian; Tahir, Muhammad Naveed

    2011-01-01

    With the combination of field survey and EPIC modeling, this paper simulated the restoration effect of soil moisture in different alfalfa (Medicago sativa)-grain rotation systems in semi-arid and drought-prone regions of Loess Plateau. In perennial alfalfa field and in grain crop field after alfalfa, the correlation coefficients between the simulated and observed values of soil moisture content in 0-10 m layer were larger than 0.9 (P alfalfa field. During the cultivation of alfalfa, the soil moisture content in the layers at 8-10 m depth should not be less than 5.7%. Considering the sustainable development of agricultural production, the appropriate cultivation duration of alfalfa should be 4-6 years and no more than 8 years. For the restoration of soil moisture after alfalfa cultivation in the study regions, the rotation system potato (Solanum tuberosum) --> potato --> spring wheat (Triticum aestivum) could be adopted, and alfalfa could be cultivated again after 32-33 years.

  1. Relationship between photosynthetic capacity, nitrogen assimilation and nodule metabolism in alfalfa (Medicago sativa) grown with sewage sludge.

    Science.gov (United States)

    Antolín, M Carmen; Fiasconaro, M Laura; Sánchez-Díaz, Manuel

    2010-10-15

    Sewage sludge has been used as N fertilizer because it contains some of inorganic N, principally as nitrate and ammonium ions. However, sewage sludge addition to legumes could result in impaired nodule metabolism due to the presence of inorganic N from sludge. A greenhouse experiment was conducted to examine the effects of sewage sludge on growth, photosynthesis, nitrogen assimilation and nodule metabolism in alfalfa (Medicago sativa L. cv. Aragón). Plants were grown in pots with a mixture of perlite and vermiculite (2:1, v/v). The experiment included three treatments: (1) plants inoculated with rhizobia and amended with sewage sludge at rate of 10% (w/w) (RS); (2) plants inoculated with rhizobia without any amendment (R); and (3) non-inoculated plants fed with ammonium nitrate (N). N(2)-fixing plants had lower growth and sucrose phosphate synthase activity but higher photosynthesis than nitrate-fed plants because they compensated the carbon cost of the rhizobia. However, sewage sludge-treated plants evidenced a loss of carbon sink strength due to N(2) fixation by means of decreased photosynthetic capacity, leaf chlorophylls and N concentration in comparison to untreated plants. Sewage sludge did no affect nodulation but decreased nodule enzyme activities involved in carbon and N metabolisms that may lead to accumulation of toxic N-compounds.

  2. 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.

  3. Plant regeneration from proroplasts of alfalfa (Medicago sativa) via somatic embryogenesis

    OpenAIRE

    Monteiro, Mariza; Appezzato-da-Glória, Beatriz; Valarini,Maria José; Oliveira, Carlos Alberto; Vieira, Maria Lucia Carneiro

    2003-01-01

    Alfalfa is one of the most frequently studied species from the production of tissue culture-derived embryos point of view. In this study, five alfalfa cultivars were analyzed with reference to their ability to regenerate plants from protoplast cultures via somatic embryogenesis. Plant regeneration from leaf-derived protoplasts isolated from the cultivar Rangelander was achieved using a protocol defined for alfalfa cell suspension-derived embryogenesis. Because of its high efficiency, this pro...

  4. Mapping fall dormancy and winter injury in tetraploid alfalfa (Medicago sativa L.)

    Science.gov (United States)

    Alfalfa is a widely planted perennial forage crop. Dormancy in autumn (fall dormancy) is generally negatively correlated with winter injury in alfalfa. To understand the genetic basis of the two traits, we identified quantitative trait loci (QTL) controlling autumn growth and winter injury using a...

  5. Extraction, composition, and functional properties of dried alfalfa (Medicago sativa L.) leaf protein

    Science.gov (United States)

    Alfalfa, traditionally used for animal feed, has attracted attention as a potential feedstock for biofuels and the viability of the process would be enhanced by co-products with value-added uses. This study describes extraction of protein from dried alfalfa leaves and the functional properties of th...

  6. The Productivity and Quality of Alfalfa (Medicago sativa L. in Romanian Forest Steppe

    Directory of Open Access Journals (Sweden)

    Mihai STAVARACHE

    2015-04-01

    Full Text Available Alternative use of alfalfa, for various purposes, including the production of biofuels or food supplement for human alimentation, is a study topic still in its early stages of research. Studying and understanding the biology of alfalfa and the factors with a major influence on it are very important activities. The productivity and quality of alfalfa are two indicators that help determine, in addition to economic value, the way in which alfalfa can be used. Evolution of alfalfa yield and quality depends on many factors, such as the growth stage of alfalfa plants at harvesting. It was observed over three years of vegetation the influence of alfalfa plant growth stage at harvest on plant height, leaves/stems ratio, production of leaves, stems and whole plant (DM - dry matter per hectare and on quality indicators (CP - crude protein, NDF - neutral detergent fiber and ADF - acid detergent fiber. The results showed that, with the advancement of phenological phases, from early bud stage to complete flowering, the total biomass output raised from 2.79 Mg·ha-1 to 4.60 Mg·ha-1, the neutral detergent fiber raised from 48.4-50.6% to 62.0-67.7%, while crude protein content decreased from 21.2-24.0% to 13.3-16.5%. The parameter values were correlated with alfalfa growth stage during the harvesting (significant at the 0.05 and 0.01 probability levels.

  7. Evaluación cuantitativa de diez variedades de alfalfa (Medicago sativa L.).

    OpenAIRE

    Álvarez Vázquez, Perpetuo

    2013-01-01

    En México, la alfalfa es la leguminosa más utilizada en la alimentación del ganado lechero, debido a su alto rendimiento y valor nutritivo. El objetivo del presente estudio fue evaluar las variables que determinan el crecimiento y rendimiento de diez variedades de alfalfa a intervalos de corte definidos estacionalmente. El estudio se realizó de septiembre de 2011 a septiembre de 2012 en el Colegio de Postgraduados, Campus Montecillo, Texcoco, México. Las variedades de alfalfa estudiadas fuero...

  8. Phosphate Rock Application on Alfalfa (Medicago sativa L. Production and Macronutrients in Latosol Soil

    Directory of Open Access Journals (Sweden)

    Y. Liani

    2011-12-01

    Full Text Available The objective of this study was to evaluate the effectiveness of phosphate rocks (PRs fertilizer compared to chemical P fertilizer for the best crop production and macronutrients of alfalfa. A completely randomized design under 3x3 factorial patterns was used in this research. The first factor was different sources of P fertilizer: Guizhou Phosphate Rock (GPR, Jingxiang Phosphate Rock (JPR, and Single Super Phosphate (SSP. The second factor was level of P fertilizer: 75, 100, and 125 mg P2O5/kg soil. A control treatment (without addition of P fertilizer, CK was added as a comparison with the treatments. The results showed that JPR was the best for alfalfa production, whereas GPR and SSP were better for nutrient content in the alfalfa tissue than JPR. On the whole, phosphate rocks had similar effect on alfalfa growth compared to SSP at the experimental conditions.

  9. Role of Silicon Counteracting Cadmium Toxicity in Alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Kabir, Ahmad H; Hossain, Mohammad M; Khatun, Most A; Mandal, Abul; Haider, Syed A

    2016-01-01

    Cadmium (Cd) is one of the most phytotoxic elements causing an agricultural problem and human health hazards. This work investigates whether and how silicon (Si) ameliorates Cd toxicity in Alfalfa. The addition of Si in Cd-stressed plants caused significant improvement in morpho-physiological features as well as total protein and membrane stability, indicating that Si does have critical roles in Cd detoxification in Alfalfa. Furthermore, Si supplementation in Cd-stressed plants showed a significant decrease in Cd and Fe concentrations in both roots and shoots compared with Cd-stressed plants, revealing that Si-mediated tolerance to Cd stress is associated with Cd inhibition in Alfalfa. Results also showed no significant changes in the expression of two metal chelators [MsPCS1 (phytochelatin synthase) and MsMT2 (metallothionein)] and PC (phytochelatin) accumulation, indicating that there may be no metal sequestration or change in metal sequestration following Si application under Cd stress in Alfalfa. We further performed a targeted study on the effect of Si on Fe uptake mechanisms. We observed the consistent reduction in Fe reductase activity, expression of Fe-related genes [MsIRT1 (Fe transporter), MsNramp1 (metal transporter) and OsFRO1 (ferric chelate reductase] and Fe chelators (citrate and malate) by Si application to Cd stress in roots of Alfalfa. These results support that limiting Fe uptake through the down-regulation of Fe acquisition mechanisms confers Si-mediated alleviation of Cd toxicity in Alfalfa. Finally, an increase of catalase, ascorbate peroxidase, and superoxide dismutase activities along with elevated methionine and proline subjected to Si application might play roles, at least in part, to reduce H2O2 and to provide antioxidant defense against Cd stress in Alfalfa. The study shows evidence of the effect of Si on alleviating Cd toxicity in Alfalfa and can be further extended for phytoremediation of Cd toxicity in plants.

  10. Role of Silicon Counteracting Cadmium Toxicity in Alfalfa (Medicago sativa L.)

    Science.gov (United States)

    Kabir, Ahmad H.; Hossain, Mohammad M.; Khatun, Most A.; Mandal, Abul; Haider, Syed A.

    2016-01-01

    Cadmium (Cd) is one of the most phytotoxic elements causing an agricultural problem and human health hazards. This work investigates whether and how silicon (Si) ameliorates Cd toxicity in Alfalfa. The addition of Si in Cd-stressed plants caused significant improvement in morpho-physiological features as well as total protein and membrane stability, indicating that Si does have critical roles in Cd detoxification in Alfalfa. Furthermore, Si supplementation in Cd-stressed plants showed a significant decrease in Cd and Fe concentrations in both roots and shoots compared with Cd-stressed plants, revealing that Si-mediated tolerance to Cd stress is associated with Cd inhibition in Alfalfa. Results also showed no significant changes in the expression of two metal chelators [MsPCS1 (phytochelatin synthase) and MsMT2 (metallothionein)] and PC (phytochelatin) accumulation, indicating that there may be no metal sequestration or change in metal sequestration following Si application under Cd stress in Alfalfa. We further performed a targeted study on the effect of Si on Fe uptake mechanisms. We observed the consistent reduction in Fe reductase activity, expression of Fe-related genes [MsIRT1 (Fe transporter), MsNramp1 (metal transporter) and OsFRO1 (ferric chelate reductase] and Fe chelators (citrate and malate) by Si application to Cd stress in roots of Alfalfa. These results support that limiting Fe uptake through the down-regulation of Fe acquisition mechanisms confers Si-mediated alleviation of Cd toxicity in Alfalfa. Finally, an increase of catalase, ascorbate peroxidase, and superoxide dismutase activities along with elevated methionine and proline subjected to Si application might play roles, at least in part, to reduce H2O2 and to provide antioxidant defense against Cd stress in Alfalfa. The study shows evidence of the effect of Si on alleviating Cd toxicity in Alfalfa and can be further extended for phytoremediation of Cd toxicity in plants. PMID:27512401

  11. Role of silicon counteracting cadmium toxicity in Alfalfa (Medicago sativa L.

    Directory of Open Access Journals (Sweden)

    Ahmad H. Kabir

    2016-07-01

    Full Text Available Cadmium (Cd is one of the most phytotoxic elements causing an agricultural problem and human health hazards. This work investigates whether and how silicon (Si ameliorates Cd toxicity in Alfalfa. The addition of Si in Cd-stressed plants caused significant improvement in morpho-physiological features as well as total protein and membrane stability, indicating that Si does have critical roles in Cd detoxification in Alfalfa. Furthermore, Si supplementation in Cd-stressed plants showed a significant decrease in Cd and Fe concentrations in both roots and shoots compared with Cd-stressed plants, revealing that Si-mediated tolerance to Cd stress is associated with Cd inhibition in Alfalfa. Results also showed no significant changes in the expression of two metal chelators [MsPCS1 (phytochelatin synthase and MsMT2 (metallothionein] and PC (phytochelatin accumulation, indicating that there may be no metal sequestration or change in metal sequestration following Si application under Cd stress in Alfalfa. We further performed a targeted study on the effect of Si on Fe uptake mechanisms. We observed the consistent reduction in Fe reductase activity, expression of Fe-related genes [MsIRT1 (Fe transporter, MsNramp1 (metal transporter and OsFRO1 (ferric chelate reductase] and Fe chelators (citrate and malate by Si application to Cd stress in roots of Alfalfa. These results support that limiting Fe uptake through the down-regulation of Fe acquisition mechanisms confers Si-mediated alleviation of Cd toxicity in Alfalfa. Finally, an increase of catalase (CAT, ascorbate peroxidase (APX and superoxide dismutase (SOD activities along with elevated methionine and proline subjected to Si application might play roles, at least in part, to reduce H2O2 and to provide antioxidant defense against Cd stress in Alfalfa. The study shows evidence of the effect of Si on alleviating Cd toxicity in Alfalfa and can be further extended for phytoremediation of Cd toxicity in plants.

  12. De novo characterization of fall dormant and nondormant alfalfa (Medicago sativa L.) leaf transcriptome and identification of candidate genes related to fall dormancy.

    Science.gov (United States)

    Zhang, Senhao; Shi, Yinghua; Cheng, Ningning; Du, Hongqi; Fan, Wenna; Wang, Chengzhang

    2015-01-01

    Alfalfa (Medicago sativa L.) is one of the most widely cultivated perennial forage legumes worldwide. Fall dormancy is an adaptive character related to the biomass production and winter survival in alfalfa. The physiological, biochemical and molecular mechanisms causing fall dormancy and the related genes have not been well studied. In this study, we sequenced two standard varieties of alfalfa (dormant and non-dormant) at two time points and generated approximately 160 million high quality paired-end sequence reads using sequencing by synthesis (SBS) technology. The de novo transcriptome assembly generated a set of 192,875 transcripts with an average length of 856 bp representing about 165.1 Mb of the alfalfa leaf transcriptome. After assembly, 111,062 (57.6%) transcripts were annotated against the NCBI non-redundant database. A total of 30,165 (15.6%) transcripts were mapped to 323 Kyoto Encyclopedia of Genes and Genomes pathways. We also identified 41,973 simple sequence repeats, which can be used to generate markers for alfalfa, and 1,541 transcription factors were identified across 1,350 transcripts. Gene expression between dormant and non-dormant alfalfa at different time points were performed, and we identified several differentially expressed genes potentially related to fall dormancy. The Gene Ontology and pathways information were also identified. We sequenced and assembled the leaf transcriptome of alfalfa related to fall dormancy, and also identified some genes of interest involved in the fall dormancy mechanism. Thus, our research focused on studying fall dormancy in alfalfa through transcriptome sequencing. The sequencing and gene expression data generated in this study may be used further to elucidate the complete mechanisms governing fall dormancy in alfalfa.

  13. Contrasting Storage Protein Synthesis and Messenger RNA Accumulation during Development of Zygotic and Somatic Embryos of Alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Krochko, J E; Pramanik, S K; Bewley, J D

    1992-05-01

    During development on hormone-free media, somatic embryos pass through distinct morphological stages that superficially resemble those of zygotic embryo development (globular, heart, torpedo, cotyledonary stages). Despite these similarities, they differ from zygotic embryos in the extent of cotyledonary development and the patterns of synthesis and quantitative expression of seed-specific storage proteins (7S, 11S, and 2S proteins). Alfin (7S) is the first storage protein synthesized in developing zygotic embryos (stage IV). The 11S (medicagin) and 2S (Low Molecular Weight, LMW) storage proteins are not detectable until the following stage of development (stage V), although all three are present before the completion of embryo enlargement. Likewise, the 7S storage protein is the first to be synthesized in developing somatic embryos (day 5). Medicagin is evident by day 7 and the LMW protein by day 10. In contrast to zygotic embryos, alfin remains the predominant storage protein in somatic embryos throughout development. Not only are the relative amounts of medicagin and the LMW protein reduced in somatic embryos but the LMW protein is accumulated much later than the other proteins. Quantification of the storage protein mRNAs (7S, 11S, and 2S) by northern blot analysis confirms that there are substantial differences in the patterns of message accumulation in zygotic and somatic embryos of alfalfa (Medicago sativa). In zygotic embryos, the 7S, 11S, and 2S storage protein mRNAs are abundant during maturation and, in particular, during the stages of maximum protein synthesis (alfin, stages VI and VII; medicagin, stage VII; LMW, stage VII). In somatic embryos, the predominance of the 7S storage protein is correlated with increased accumulation of its mRNA, whereas the limited synthesis of the 11S storage protein is associated with much lower steady-state levels of its message. The mRNA for the LMW protein is present already by 3 days after transfer to hormone-free media

  14. The Medicago sativa gene index 1.2: a web-accessible gene expression atlas for investigating expression differences between Medicago sativa subspecies

    Science.gov (United States)

    Alfalfa (Medicago sativa L.) is the primary forage legume crop species in the United States and plays essential economic and ecological roles in agricultural systems across the country. Modern alfalfa is the result of hybridization between tetraploid M. sativa ssp. sativa and M. sativa ssp. falcata....

  15. Genome-Wide Association Study Identifies Loci for Salt Tolerance during Germination in Autotetraploid Alfalfa (Medicago sativa L.) Using Genotyping-by-Sequencing.

    Science.gov (United States)

    Yu, Long-Xi; Liu, Xinchun; Boge, William; Liu, Xiang-Ping

    2016-01-01

    Salinity is one of major abiotic stresses limiting alfalfa (Medicago sativa L.) production in the arid and semi-arid regions in US and other counties. In this study, we used a diverse panel of alfalfa accessions previously described by Zhang et al. (2015) to identify molecular markers associated with salt tolerance during germination using genome-wide association study (GWAS) and genotyping-by-sequencing (GBS). Phenotyping was done by germinating alfalfa seeds under different levels of salt stress. Phenotypic data of adjusted germination rates and SNP markers generated by GBS were used for marker-trait association. Thirty six markers were significantly associated with salt tolerance in at least one level of salt treatments. Alignment of sequence tags to the Medicago truncatula genome revealed genetic locations of the markers on all chromosomes except chromosome 3. Most significant markers were found on chromosomes 1, 2, and 4. BLAST search using the flanking sequences of significant markers identified 14 putative candidate genes linked to 23 significant markers. Most of them were repeatedly identified in two or three salt treatments. Several loci identified in the present study had similar genetic locations to the reported QTL associated with salt tolerance in M. truncatula. A locus identified on chromosome 6 by this study overlapped with that by drought in our previous study. To our knowledge, this is the first report on mapping loci associated with salt tolerance during germination in autotetraploid alfalfa. Further investigation on these loci and their linked genes would provide insight into understanding molecular mechanisms by which salt and drought stresses affect alfalfa growth. Functional markers closely linked to the resistance loci would be useful for MAS to improve alfalfa cultivars with enhanced resistance to drought and salt stresses.

  16. Evaluation of alfalfa (Medicago sativa L.) populations' response to salinity stress

    Science.gov (United States)

    Alfalfa is a moderately salt tolerant crop with high economic return, therefore more suitable for production with lower quality water than most high value crops. This study was conducted to examine the effects of the irrigation water salt type (ST=Cl- or SO4 2-) and five salinity levels (ECiw= 0.85,...

  17. EFICIENCIA DEL AGUA DE RIEGO EN LA PRODUCCIÓN DE MAÍZ FORRAJERO (Zea mays L.) Y ALFALFA (Medicago sativa): IMPACTO SOCIAL Y ECONÓMICO

    OpenAIRE

    Aurelio Pedroza Sandoval; José Luis Ríos Flores; Myriam Torres Moreno; Jesús Enrique Cantú Brito; Cesar Piceno Sagarnaga; Luis Gerardo Yáñez Chávez

    2014-01-01

    El maíz y la alfalfa, son los dos principales cultivos forrajeros en la Cuenca Lechera de la Laguna de los estados de Coahuila y Durango, México, donde el recurso hídrico es el mayor factor limitante. El objetivo de este estudio fue hacer una evaluación de la eficiencia biológica, económica y social del uso de agua de riego en los cultivos de maíz forrajero (Zea mays L.) y alfalfa (Medicago sativa), mediante un análisis económico comparativo y de eficiencia de productividad. El maíz fue más e...

  18. Co-transforming bar and CsLEA enhanced tolerance to drought and salt stress in transgenic alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Zhang, Jiyu; Duan, Zhen; Zhang, Daiyu; Zhang, Jianquan; Di, Hongyan; Wu, Fan; Wang, Yanrong

    2016-03-25

    Drought and high salinity are two major abiotic factors that restrict alfalfa productivity. A dehydrin protein, CsLEA, from the desert grass Cleistogenes songorica was transformed into alfalfa (Medicago sativa L.) via Agrobacterium-mediated transformation using the bar gene as a selectable marker, and the drought and salt stress tolerances of the transgenic plants were assessed. Thirty-nine of 119 transformants were positive, as screened by Basta, and further molecularly authenticated using PCR and RT-PCR. Phenotype observations revealed that the transgenic plants grew better than the wild-type (WT) plants after 15d of drought stress and 10d of salt stress: the leaves of WT alfalfa turned yellow, whereas the transgenic alfalfa leaves only wilted; after rewatering, the transgenic plants returned to a normal state, though the WT plants could not be restored. Evaluation of physiologic and biochemical indices during drought and salt stresses showed a relatively lower Na(+) content in the leaves of the transgenic plants, which would reduce toxic ion effects. In addition, the transgenic plants were able to maintain a higher relative water content (RWC), higher shoot biomass, fewer photosystem changes, decreased membrane injury, and a lower level of osmotic stress injury. These results demonstrate that overexpression of the CsLEA gene can enhance the drought and salt tolerance of transgenic alfalfa; in addition, carrying the bar gene in the genome may increase herbicide resistance.

  19. Increase phosphorus availability from the use of alfalfa (Medicago sativa L) green manure in rice (Oryza sativa L.) agroecosystem.

    Science.gov (United States)

    Gao, Xiaoye; Shi, Dongyan; Lv, Aimin; Wang, Shengyin; Yuan, Shili; Zhou, Peng; An, Yuan

    2016-11-11

    Alfalfa is a good green manure source, but its effect on rice growth has not been fully elucidated. Two green manure species, alfalfa and broad bean (Vicia faba L.), and two N fertilizer levels, alone or combination, were applied to a rice field. The results indicated that alfalfa had more pronounced effects on increasing soil labile phosphorus (P) fractions (including NaHCO3-Pi, NaOH-Pi), P uptake and soil enzyme activities (dehydrogenase, urease, acid phosphatase and β-glucosidase) than broad bean and N fertilizer. The transformation of NaHCO3-Po to labile P regulated by alfalfa played a significant direct and indirect effect on grain yield. Although a much lower N input from alfalfa addition, a similar grain yield with N fertilizer treatment was achieved, and the integration of alfalfa with N fertilizer produced the highest grain yield and P availability, which was associated with the highest urease, acid phosphatase and β-glucosidase activity in soil. These results indicate that alfalfa green manure had a great ability of increasing grain yield through enhancing P availability in rice paddy, which could give us a way to reduce N fertilizer application by enhancing P availability.

  20. Increase phosphorus availability from the use of alfalfa (Medicago sativa L) green manure in rice (Oryza sativa L.) agroecosystem

    Science.gov (United States)

    Gao, Xiaoye; Shi, Dongyan; Lv, Aimin; Wang, Shengyin; Yuan, Shili; Zhou, Peng; An, Yuan

    2016-01-01

    Alfalfa is a good green manure source, but its effect on rice growth has not been fully elucidated. Two green manure species, alfalfa and broad bean (Vicia faba L.), and two N fertilizer levels, alone or combination, were applied to a rice field. The results indicated that alfalfa had more pronounced effects on increasing soil labile phosphorus (P) fractions (including NaHCO3-Pi, NaOH-Pi), P uptake and soil enzyme activities (dehydrogenase, urease, acid phosphatase and β-glucosidase) than broad bean and N fertilizer. The transformation of NaHCO3-Po to labile P regulated by alfalfa played a significant direct and indirect effect on grain yield. Although a much lower N input from alfalfa addition, a similar grain yield with N fertilizer treatment was achieved, and the integration of alfalfa with N fertilizer produced the highest grain yield and P availability, which was associated with the highest urease, acid phosphatase and β-glucosidase activity in soil. These results indicate that alfalfa green manure had a great ability of increasing grain yield through enhancing P availability in rice paddy, which could give us a way to reduce N fertilizer application by enhancing P availability. PMID:27833163

  1. Identification and Selection for Salt Tolerance in Alfalfa (Medicago sativa L. Ecotypes via Physiological Traits

    Directory of Open Access Journals (Sweden)

    Hassan MONIRIFAR

    2009-12-01

    Full Text Available Salt stress is a serious environmental problem throughout the world which may be partially relieved by breeding cultivars that can tolerate salt stress. Plant breeding may provide a relatively cost effective short-term solution to the salinity problem by producing cultivars able to remain productive at low to moderate levels of salinity. Five alfalfa cultivars, �Seyah-Roud�, �Ahar-Hourand�, �Oskou�, �Malekan� and �Sefida-Khan� were assessed for salt tolerance at mature plant stage. A greenhouse screening system was used to evaluate individual alfalfa plants grown in perlit medium, and irrigated with water containing different amounts of NaCl. Three salt levels were achieved by adding 0, 100 and 200 mM NaCl to Hoagland nutrient solution, respectively. Forage yield, sodium and potassium contents and K/Na ratio was determined. Also, leaf samples were analyzed for proline and chlorophyll contents. The ecotypes Seyha-Roud and �Sefida-Khan� had comparatively less sodium contents than �Oskou�, �Ahar-Hourand� and �Malekan� ecotypes, also potassium content increased under saline condition. Forage yield of different alfalfa ecotypes was significantly influenced by the salinity. The ecotypes �Malekan�, Ahar- Hourand and �Oskou� were successful in maintaining forage yield under salinity stress. Sodium contents increased due to salinity in all alfalfa ecotypes however ecotypes �Ahar-Hourand� and �Malekan� maintained the highest leaf Na concentration. They showed higher content of K than other ecotypes but had lower K/Na ratio. It was concluded that, two ecotypes �Malekan� and �Ahar-Hourand� were better.

  2. A CLIPS expert system for maximizing alfalfa (Medicago Sativa L.) production

    Science.gov (United States)

    Engel, B. A.; Jones, D. D.; Rhykerd, R. L.; Rhykerd, L. M.; Rhykerd, C. L., Jr.; Rhykerd, C. L.

    1990-01-01

    An alfalfa management expert system originally developed by Purdue University agricultural scientists on the PC Plus expert system shell from Texas Instrument has been updated and successfully converted to CLIPS (C Language Integrated Production System). This reduces the cost and legal restrictions associated with making the expert system available to agribusiness industries, extension personnel and farm managers and operators. The expert system includes recommendations concerning soil drainage, liming, P and K fertilization, weed control, variety selection and seeding rate including pure live seeds.

  3. Association of AFLP and SCAR markers with common leafspot resistance in autotetraploid alfalfa (Medicago sativa).

    Science.gov (United States)

    Wang, Y; Bi, B; Yuan, Q H; Li, X L; Gao, J M

    2012-03-14

    To identify amplified fragment length polymorphism (AFLP) markers associated with resistance or susceptibility of alfalfa to common leafspot (CLS) caused by the fungus Pseudopeziza medicaginis (Dermateaceae), bulked segregant analysis was conducted based on an F(1(M × M)) population of 93 plants and a BC(1)S population of 91 plants. Three AFLP markers, ACTCAA(R206), TAGCAC(R185), and GGACTA(S264), were found to be associated with CLS resistance or susceptibility. All three markers were found at significantly different frequencies (71.9, 80.3 and 91.8%) compared to resistant or susceptible plants in the original population. Subsequently, these three AFLP markers were converted into three SCAR markers, ACTCAA(R136), TAGCAC(R128) and GGACTA(S254), which are easier to employ in breeding programs. The three SCAR markers were used in a randomly selected population with 50% resistance; the probability of finding one resistant plant was increased to 67.3, 66.7 and 90.0% with markers ACTCAA(R136), TAGCAC(R128) and GGACTA(S254), independently. If two of the SCAR markers were used simultaneously, the probability would be higher than 89%. The three SCAR markers identified in this study would be applicable for selection for CLS resistance in alfalfa breeding programs. Moreover, the genetic analysis indicated that CLS resistance in alfalfa is conferred by a single dominant gene.

  4. IDENTIFICATION OF SOIL FUNGI ISOLATED FROM ALFALFA (Medicago sativa L TO FIND SPECIFIC FUNGI WHICH IMPROVED THE GROWTH OF ALFALFA

    Directory of Open Access Journals (Sweden)

    T. Yudiarti

    2014-10-01

    Full Text Available Objective of the study was to identify all kinds of fungi which can life in the alfalfa plantation inBaturaden Purwokerto-Central Java. Fungi used in this study was 38 isolates. All fungi have been takenfrom the isolation of soil and root of diseased plant. Macroscopic and microscopic methods were usedfor identification. Potato Dextrose Agar (PDA medium was used to grow the fungi. All fungi wereidentified using book identification of fungi. The results showed that from 38 isolates, six species wasdetermined and one was unidentifed. Those species identified were Cuninghammela sp, Trichoderma sp,Vertilicium sp, Eupenicillium sp, Pythium sp, Aspergillus sp.

  5. Identification and Selection for Salt Tolerance in Alfalfa (Medicago sativa L.) Ecotypes via Physiological Traits

    OpenAIRE

    Monirifar, Hassan; Maryam BARGHI

    2009-01-01

    Salt stress is a serious environmental problem throughout the world which may be partially relieved by breeding cultivars that can tolerate salt stress. Plant breeding may provide a relatively cost effective short-term solution to the salinity problem by producing cultivars able to remain productive at low to moderate levels of salinity. Five alfalfa cultivars, �Seyah-Roud�, �Ahar-Hourand�, �Oskou�, �Malekan� and �Sefida-Khan� were assessed for salt tolerance at mature plant stage. A greenhou...

  6. Effects of drought stress on germination characters of some alfalfa (Medicago sativa L. varieties

    Directory of Open Access Journals (Sweden)

    Emine BUDAKLI ÇARPICI

    2015-12-01

    Full Text Available This study was conducted to determine the responses of some alfalfa varieties to different drought stress at germination stage. Alfalfa varieties Bilensoy-80, Alsancak, Gözlü-1, Prosementi and Isıde were used as plant materials. Four different drought stress levels (0, -2.95, -4.91 and -10.27 bar were handled in this study and were used Polyethylene glycol-6000 (PEG-6000 to create of drought stress at different levels. The experiment was conducted as completely randomized design with two factors and four replications. In the experiment, some characters such as germination percentage, plumula length, radicle length and vigour index were examined. The results revealed that drought stress had a significant effect on all characters. Germination percentage, plumula length, radicle length, and vigour index ranged 0.00-99.50 %, 0.00-43.24 mm, 0.00-54.45 mm and 0.00-43.79, respectively. Considering germination percentage, the cultivars tolerated the drought stress up to-4.91 bar, but after this level germination percentage decreased significantly. In terms of plumula length and vigour index, the cultivars tolerated the drought stress up to -2.95 bar and in terms of radicle length the cultivars tolerated the drought stress up to -4.91 bar and were observed a significant decreases or deaths after this levels. Bilensoy-80 and Alsancak had been more successful for drought than the other varieties in experiment.

  7. Overexpression of Medicago sativa TMT elevates the α-tocopherol content in Arabidopsis seeds, alfalfa leaves, and delays dark-induced leaf senescence.

    Science.gov (United States)

    Jiang, Jishan; Jia, Huili; Feng, Guangyan; Wang, Zan; Li, Jun; Gao, Hongwen; Wang, Xuemin

    2016-08-01

    Alfalfa (Medicago sativa L.) is a major forage legume for livestock and a target for improving their dietary quality. Vitamin E is an essential vitamin that animals must obtain from their diet for proper growth and development. γ-tocopherol methyltransferase (γ-TMT), which catalyzes the conversion of δ- and γ-tocopherols (or tocotrienols) to β- and α-tocopherols (or tocotrienols), respectively, is the final enzyme involved in the vitamin E biosynthetic pathway. The overexpression of M. sativa L.'s γ-TMT (MsTMT) increased the α-tocopherol content 10-15 fold above that of wild type Arabidopsis seeds without altering the total content of vitamin E. Additionally, in response to osmotic stress, the biomass and the expression levels of several osmotic marker genes were significantly higher in the transgenic lines compared with wild type. Overexpression of MsTMT in alfalfa led to a modest, albeit significant, increase in α-tocopherol in leaves and was also responsible for a delayed leaf senescence phenotype. Additionally, the crude protein content was increased, while the acid and neutral detergent fiber contents were unchanged in these transgenic lines. Thus, increased α-tocopherol content occurred in transgenic alfalfa without compromising the nutritional qualities. The targeted metabolic engineering of vitamin E biosynthesis through MsTMT overexpression provides a promising approach to improve the α-tocopherol content of forage crops.

  8. Excessive ammonia inhibited transcription of MsU2 gene and furthermore affected accumulation distribution of allantoin and amino acids in alfalfa Medicago sativa

    Institute of Scientific and Technical Information of China (English)

    WANG Li; JIANG Lin-lin; Nomura Mika; Tajima Shigeyuki; CHENG Xian-guo

    2015-01-01

    In legume plants, uricase gene (Nodulin-35) plays a positive role in metabolism of ureide and amide compounds in symbiotic nitrogen-ifxing in the nodules. In this study, a pot experiment was performed to examine the effects of ammonium application on the transcription of MsU2 gene and distribution of major nitrogen compounds in alfalfa Medicago sativa. Data showed that alfalfa plant has a signiifcant difference in contents of nitrogen compounds in xylem saps compared with soybean plant, and belongs to typical amide type legume plants with little ureide accumulation, and the accumulation of asparagines and ureide in the tissues of alfalfa is mainly gathered in the nodules. Northern blotting showed that excessive ammonium signiifcantly inhibited the transcription of MsU2 gene in the nodules and roots, and mRNA accumulation of MsU2 gene in the plants exposed to excessive ammonium decreased gradual y with culture time extension, indicating that application of ammonium signiifcantly inhibited the transcription of MsU2 gene in the alfalfa plants. Although the application of exces-sive ammonium increased the contents of amino acids in various tissues of alfalfa, the accumulation of al antoin relfecting the strength of uricase activity is remarkably reduced in the xylem saps, stems and nodules when alfalfa plants exposed to excessive ammonium, suggesting that application of excessive ammonium generated a negative effect on symbiosis ifxing-nitrogen system due to inhibition of ammonium ion on uricase activity in the nodules of alfalfa. This result seems to imply that application of excessive ammonium in legume plants should not be proposed to avoid affecting the ability of ifxing nitrogen in the nodules of legume plants, and reasonable dose of ammonium should be recommended to effectively utilize the ifxed N from atmosphere in legume plant production.

  9. Rhizobium favelukesii sp. nov., isolated from the root nodules of alfalfa (Medicago sativa L).

    Science.gov (United States)

    Torres Tejerizo, Gonzalo; Rogel, Marco Antonio; Ormeño-Orrillo, Ernesto; Althabegoiti, María Julia; Nilsson, Juliet Fernanda; Niehaus, Karsten; Schlüter, Andreas; Pühler, Alfred; Del Papa, María Florencia; Lagares, Antonio; Martínez-Romero, Esperanza; Pistorio, Mariano

    2016-11-01

    Strains LPU83T and Or191 of the genus Rhizobium were isolated from the root nodules of alfalfa, grown in acid soils from Argentina and the USA. These two strains, which shared the same plasmid pattern, lipopolysaccharide profile, insertion-sequence fingerprint, 16S rRNA gene sequence and PCR-fingerprinting pattern, were different from reference strains representing species of the genus Rhizobium with validly published names. On the basis of previously reported data and from new DNA-DNA hybridization results, phenotypic characterization and phylogenetic analyses, strains LPU83T and Or191 can be considered to be representatives of a novel species of the genus Rhizobium, for which the name Rhizobium favelukesii sp. nov. is proposed. The type strain of this species is LPU83T (=CECT 9014T=LMG 29160T), for which an improved draft-genome sequence is available.

  10. Replacement of alfalfa hay (Medicago sativa) with maralfalfahay (Pennisetum sp.) in diets of lactating dairy goats

    DEFF Research Database (Denmark)

    Criscioni, P.; Marti, J.V.; Pérez-Baena, I.;

    2016-01-01

    of body weight [BW]) were selected in a 2-treatment and crossoverdesign experiment where each goat received both treatments in 2 periods. One group offive goats was fed a mixed ration with alfalfa as forage (A diet) and the other diet replacedalfalfa with maralfalfa (M diet) in a forage concentrate ratio...... of 40/60. Diets were isoen-ergetic and isoproteic. The goats were allocated to individual metabolism cages. After 17d of adaptation, feed intake, total faecal and urine output and milk yield were recordeddaily over a 5 d period. Then, gas exchange measurements were recorded individually by amobile open...... milkyield (1.8 vs. 1.7 kg/d) and CH4emissions (28.5 vs. 25.9 g/d) in A compared to M diet wereobserved, respectively. Use of tropical grasses such as maralfalfa in temperate climatescould be a strategy for farmers to incorporate forage into feed for flocks, as milk chemicalcomposition did not change...

  11. Seed Priming to Overcome Salinity Stress in Persian Cultivars of Alfalfa (Medicago sativa L.

    Directory of Open Access Journals (Sweden)

    Ali SEPEHRI

    2015-03-01

    Full Text Available In order to investigate the effect of hydro-priming on seed germination with distilled water on germination of five Alfalfa cultivars under salinity stress, an experiment was conducted as a factorial experiment based on a completely randomized design with three replications. Seven levels of hydro-priming and salinity of NaCl including prime and non-salinity, prime and 50 mM salinity, prime and 100 mM salinity, prime and 150 mM salinity, prime and 200 mM salinity, prime and 250 mM salinity and without prime and salinity and five alfalfa varieties, including ‘Hamedani’, ‘Isfahani’, ‘Bami’, ‘Yazdi’ and ‘Ghareh Yonjeh’ were used. The results showed that the main effect of prime, salinity and cultivars and their interaction in all studied traits were significantly affected at the 5% probability level. Priming treatments in non-salinity of all cultivars were the highest. In all cultivars, final germination percentage, length and weight of radicle, plumule and seedling, germination rate and time, relative radicle elongation, vigor index and stress index, were significantly improved in response to priming in salinity levels of 50-200 mM, compared to control. Radicle produced higher length and weight than the plumule in hydro- priming and salinity treatments. ‘Hamedani’ cultivar in most of studied characteristics had a better response than others. The lowest response to salinity stress and priming was observed in ‘Yazdi’ cultivar.

  12. Co-expression of bacterial aspartate kinase and adenylylsulfate reductase genes substantially increases sulfur amino acid levels in transgenic alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Tong, Zongyong; Xie, Can; Ma, Lei; Liu, Liping; Jin, Yongsheng; Dong, Jiangli; Wang, Tao

    2014-01-01

    Alfalfa (Medicago sativa L.) is one of the most important forage crops used to feed livestock, such as cattle and sheep, and the sulfur amino acid (SAA) content of alfalfa is used as an index of its nutritional value. Aspartate kinase (AK) catalyzes the phosphorylation of aspartate to Asp-phosphate, the first step in the aspartate family biosynthesis pathway, and adenylylsulfate reductase (APR) catalyzes the conversion of activated sulfate to sulfite, providing reduced sulfur for the synthesis of cysteine, methionine, and other essential metabolites and secondary compounds. To reduce the feedback inhibition of other metabolites, we cloned bacterial AK and APR genes, modified AK, and introduced them into alfalfa. Compared to the wild-type alfalfa, the content of cysteine increased by 30% and that of methionine increased substantially by 60%. In addition, a substantial increase in the abundance of essential amino acids (EAAs), such as aspartate and lysine, was found. The results also indicated a close connection between amino acid metabolism and the tricarboxylic acid (TCA) cycle. The total amino acid content and the forage biomass tested showed no significant changes in the transgenic plants. This approach provides a new method for increasing SAAs and allows for the development of new genetically modified crops with enhanced nutritional value.

  13. Combining -Omics to Unravel the Impact of Copper Nutrition on Alfalfa (Medicago sativa) Stem Metabolism.

    Science.gov (United States)

    Printz, Bruno; Guerriero, Gea; Sergeant, Kjell; Audinot, Jean-Nicolas; Guignard, Cédric; Renaut, Jenny; Lutts, Stanley; Hausman, Jean-Francois

    2016-02-01

    Copper can be found in the environment at concentrations ranging from a shortage up to the threshold of toxicity for plants, with optimal growth conditions situated in between. The plant stem plays a central role in transferring and distributing minerals, water and other solutes throughout the plant. In this study, alfalfa is exposed to different levels of copper availability, from deficiency to slight excess, and the impact on the metabolism of the stem is assessed by a non-targeted proteomics study and by the expression analysis of key genes controlling plant stem development. Under copper deficiency, the plant stem accumulates specific copper chaperones, the expression of genes involved in stem development is decreased and the concentrations of zinc and molybdenum are increased in comparison with the optimum copper level. At the optimal copper level, the expression of cell wall-related genes increases and proteins playing a role in cell wall deposition and in methionine metabolism accumulate, whereas copper excess imposes a reduction in the concentration of iron in the stem and a reduced abundance of ferritins. Secondary ion mass spectrometry (SIMS) analysis suggests a role for the apoplasm as a copper storage site in the case of copper toxicity.

  14. Risks and benefits of compost-like materials prepared by the thermal treatment of raw scallop hepatopancreas for supplying cadmium and the growth of alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Ushijima, Kensuke; Fukushima, Masami; Kanno, Shinya; Kanno, Itoko; Ohnishi, Mitsuhiro

    2016-01-01

    Scallop hepatopancreas, fishery waste, contains relatively high levels of Cd and organic nitrogen compounds, the latter of which represent a fertilizer. In this study, raw scallop hepatopancreas tissue was thermally treated with sawdust and red loam in the presence of an iron catalyst to produce compost-like materials (CLMs). Two CLM samples were prepared by varying the content of raw scallop hepatopancreas tissue: 46 wt.% for CLM-1 and 18 wt.% for CLM-2. Mixtures of control soil (CTL) and CLMs (CLM content: 10 and 25 wt.%) were examined for the growth of alfalfa (Medicago sativa L.) to evaluate the risks and benefits of using this material for fertilization. The Cd content in shoots and roots of alfalfa, that were grown in the presence of CLMs, was significantly higher than those for the plants grown in the CTL, indicating that Cd had accumulated in the plants from CLMs. The accumulation of Cd in the alfalfa roots was quite high in the case of the 25% CLM-1 sample. However, alfalfa growth was significantly promoted in the presence of 10% CLM-1. This can be attributed to the higher levels of nitrogen and humic substances, which serve as fertilizer components. Although the fertilization effect in case of CLM-1showed a potential benefit, the accumulation of Cd in alfalfa was clearly increased in the presence of both CLMs. In conclusion, the use of CLMs produced from raw scallop hepatopancreas tissue can be considered to have a desirable benefit from standpoint of its use as fertilizer, but is accompanied by a risk of the accumulation of Cd in alfalfa plants.

  15. EFICIENCIA DEL AGUA DE RIEGO EN LA PRODUCCIÓN DE MAÍZ FORRAJERO (Zea mays L. Y ALFALFA (Medicago sativa: IMPACTO SOCIAL Y ECONÓMICO

    Directory of Open Access Journals (Sweden)

    Aurelio Pedroza Sandoval

    2014-06-01

    Full Text Available El maíz y la alfalfa, son los dos principales cultivos forrajeros en la Cuenca Lechera de la Laguna de los estados de Coahuila y Durango, México, donde el recurso hídrico es el mayor factor limitante. El objetivo de este estudio fue hacer una evaluación de la eficiencia biológica, económica y social del uso de agua de riego en los cultivos de maíz forrajero (Zea mays L. y alfalfa (Medicago sativa, mediante un análisis económico comparativo y de eficiencia de productividad. El maíz fue más eficiente que la alfalfa, puesto que un m3 de agua subterránea produjo 5.72 kg de biomasa, $0.67 de ganancia por m3 de agua usada y 100 000 m3 de agua produjeron 0.65 empleos durante el ciclo del cultivo; mientras que la alfalfa produjo 0.215 kg de biomasa, $0.90 de ganancia y se generaron 0.43 empleos con los mismos volúmenes de agua indicados en el maíz. El cultivo de maíz forrajero fue más eficiente en producción de biomasa por volumen de agua utilizado y empleos generados, pero menos eficiente en ganancias, donde la alfalfa fue mejor. Una combinación durante el año de cultivos forrajeros con calidad energética y proteica como el maíz y la alfalfa respectivamente, éstos producidos bajo un programa de rotación, habrán de redundar en un equilibrio entre calidad de forraje, productividad del mismo, un mayor beneficio social y un menor impacto ambiental.

  16. Integrative analysis of transgenic alfalfa (Medicago sativa L. suggests new metabolic control mechanisms for monolignol biosynthesis.

    Directory of Open Access Journals (Sweden)

    Yun Lee

    2011-05-01

    Full Text Available The entanglement of lignin polymers with cellulose and hemicellulose in plant cell walls is a major biological barrier to the economically viable production of biofuels from woody biomass. Recent efforts of reducing this recalcitrance with transgenic techniques have been showing promise for ameliorating or even obviating the need for costly pretreatments that are otherwise required to remove lignin from cellulose and hemicelluloses. At the same time, genetic manipulations of lignin biosynthetic enzymes have sometimes yielded unforeseen consequences on lignin composition, thus raising the question of whether the current understanding of the pathway is indeed correct. To address this question systemically, we developed and applied a novel modeling approach that, instead of analyzing the pathway within a single target context, permits a comprehensive, simultaneous investigation of different datasets in wild type and transgenic plants. Specifically, the proposed approach combines static flux-based analysis with a Monte Carlo simulation in which very many randomly chosen sets of parameter values are evaluated against kinetic models of lignin biosynthesis in different stem internodes of wild type and lignin-modified alfalfa plants. In addition to four new postulates that address the reversibility of some key reactions, the modeling effort led to two novel postulates regarding the control of the lignin biosynthetic pathway. The first posits functionally independent pathways toward the synthesis of different lignin monomers, while the second postulate proposes a novel feedforward regulatory mechanism. Subsequent laboratory experiments have identified the signaling molecule salicylic acid as a potential mediator of the postulated control mechanism. Overall, the results demonstrate that mathematical modeling can be a valuable complement to conventional transgenic approaches and that it can provide biological insights that are otherwise difficult to obtain.

  17. Measuring residual feed intake in dairy heifers fed an alfalfa (Medicago sativa) cube diet.

    Science.gov (United States)

    Waghorn, G C; Macdonald, K A; Williams, Y; Davis, S R; Spelman, R J

    2012-03-01

    Selection for divergence between individuals for efficiency of feed utilization (residual feed intake, RFI) has widespread application in the beef industry and is usually undertaken when animals are fed diets based on silages with grain. The objective of this research was to develop a feeding system (using Gallagher, Hamilton, New Zealand, electronics) to measure RFI for growth in Holstein-Friesian heifers (aged 5-9 mo), and identify divergent individuals to be tested for RFI during lactation. A dry forage diet (alfalfa cubes) was fed because intakes could be measured accurately, and the New Zealand dairy industry (4.4 million milking cows in lactation) relies heavily on forage feeding. The evaluation was undertaken over 3 yr with 1,052 animals fed in a facility for 7 wk, and weighed 3 times weekly. The mean age at the start of measurements was 215 d, body weight (BW) 189 kg, and mean daily dry matter intakes averaged 6.7 kg. Body weight gain (all animals) averaged 0.88 kg/d. The RFI was determined as the residuals from the regression of mean intake on mean BW(0.75) and daily BW gain of individuals. Actual and fitted intakes were strongly related (R(2) = 0.82). In terms of gross efficiency (feed intake/BW gain), RFI+year explained 43% of the variation, BW gain+year explained 66%, and RFI+BW gain+year explained 79% of the variation (all Pdry matter/d. The most and least efficient animals will be tested for RFI during lactation and genetic markers will be identified for the trait.

  18. The 3' untranslated region of the two cytosolic glutamine synthetase (GS(1)) genes in alfalfa (Medicago sativa) regulates transcript stability in response to glutamine.

    Science.gov (United States)

    Simon, Bindu; Sengupta-Gopalan, Champa

    2010-10-01

    Glutamine synthetase (GS) catalyzes the ATP-dependent condensation of ammonia with glutamate to produce glutamine. The GS enzyme is located either in the chloroplast (GS(2)) or in the cytoplasm (GS(1)). GS(1) is encoded by a small gene family and the members exhibit differential expression pattern mostly attributed to transcriptional regulation. Based on our recent finding that a soybean GS(1) gene, Gmglnβ ( 1 ) is subject to its 3'UTR-mediated post-transcriptional regulation as a transgene in alfalfa (Medicago sativa) we have raised the question of whether the 3'UTR-mediated transcript destabilization is a more universal phenomenon. Gene constructs consisting of the CaMV35S promoter driving the reporter gene, GUS, followed by the 3'UTRs of the two alfalfa GS(1) genes, MsGSa and MsGSb, were introduced into alfalfa and tobacco. The analysis of these transformants suggests that while both the 3'UTRs promote transcript turnover, the MsGSb 3'UTR is more effective than the MsGSa 3'UTR. However, both the 3'UTRs along with Gmglnβ ( 1 ) 3'UTR respond to nitrate as a trigger in transcript turnover. More detailed analysis points to glutamine rather than nitrate as the mediator of transcript turnover. Our data suggests that the 3'UTR-mediated regulation of GS(1) genes at the level of transcript turnover is probably universal and is used for fine-tuning the expression in keeping with the availability of the substrates.

  19. Citric acid- and Tween(®) 80-assisted phytoremediation of a co-contaminated soil: alfalfa (Medicago sativa L.) performance and remediation potential.

    Science.gov (United States)

    Agnello, A C; Huguenot, D; van Hullebusch, E D; Esposito, G

    2016-05-01

    A pot experiment was designed to assess the phytoremediation potential of alfalfa (Medicago sativa L.) in a co-contaminated (i.e., heavy metals and petroleum hydrocarbons) soil and the influence of citric acid and Tween(®) 80 (polyethylene glycol sorbitan monooleate), applied individually and combined together, for their possible use in chemically assisted phytoremediation. The results showed that alfalfa plants could tolerate and grow in a co-contaminated soil. Over a 90-day experimental time, shoot and root biomass increased and negligible plant mortality occurred. Heavy metals were uptaken by alfalfa to a limited extent, mostly by plant roots, and their concentration in plant tissues were in the following order: Zn > Cu > Pb. Microbial population (alkane-degrading microorganisms) and activity (lipase enzyme) were enhanced in the presence of alfalfa with rhizosphere effects of 9.1 and 1.5, respectively, after 90 days. Soil amendments did not significantly enhance plant metal concentration or total uptake. In contrast, the combination of citric acid and Tween(®) 80 significantly improved alkane-degrading microorganisms (2.4-fold increase) and lipase activity (5.3-fold increase) in the rhizosphere of amended plants, after 30 days of experiment. This evidence supports a favorable response of alfalfa in terms of tolerance to a co-contaminated soil and improvement of rhizosphere microbial number and activity, additionally enhanced by the joint application of citric acid and Tween(®) 80, which could be promising for future phytoremediation applications.

  20. Response of cotton, alfalfa, and cantaloupe to foliar-deposited salt in an arid environment. [Gossypium hirsumtum L. ; Medicago sativa L. ; Cucumis melo L

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, W.C.; Karpiscak, M.M.; Bartels, P.G.

    The cooling towers at the Palo Verde Nuclear Generating Station (PVNGS), located 80 km west of Phoenix, AZ, will release as estimated 2.1 Mg/d of particulates (primarily salts) into the atmosphere when the station is in full operation. The saline drift will disperse and settle onto agricultural fields surrounding the station. Field studies were conducted in 1983 to investigate the influence of foliar-applied saline aerosol on crop growth, foliar injury, and tissue elemental concentration on cotton (Gossypium hirsutum L.), alfalfa (medicago sativa L.), and cantaloupe (Cucumis melo L.) in an arid environment. The treatment aerosol solutions simulated treated wastewater effluent and included all essential plant nutrients and other elements, including trace concentrations of heavy metals. The treatments included unsprayed plots, and plots sprayed with salt solutions at 0 (distilled water), 8, 83, and 415 kg/(ha yr). The alfalfa received an additional 829 kg/(ha yr) treatment. The species were evaluated in separate experiments on Mohave clay loam and Sonoita sandy loam soils (Typic Haplargid) near Marana, AZ. Cotton treated with 415 kg/(ha yr) had significantly less chlorosis and tended to be slightly taller than the cotton in the unsprayed plots. The alfalfa treated at a rate of 829 kg/(ha yr) showed significantly more leaf margin necrosis than did the unsprayed alfalfa. In the cantaloupe, there were no visually apparent differences among salt treatments. Hand-harvested cotton plots had a significant reduction is seed cotton yield at the 415 kg/(ha yr) treatment. A similar though nonsignificant, trend towards reduced yield with increased salt treatment was observed in machine-harvested cotton plots.

  1. Chloroform extract of alfalfa (Medicago sativa) inhibits lipopolysaccharide-induced inflammation by downregulating ERK/NF-κB signaling and cytokine production.

    Science.gov (United States)

    Choi, Ki-Choon; Hwang, Jung-Min; Bang, Sung-Jun; Kim, Beom-Tae; Kim, Dong-Hern; Chae, Minseon; Lee, Seung-Ah; Choi, Gi Jun; Kim, Da Hye; Lee, Jeong-Chae

    2013-05-01

    Alfalfa (Medicago sativa L.) is commonly used as a traditional medicine and functional food. This study investigated the anti-inflammatory potential of alfalfa and the mechanisms involved. The chloroform extract of alfalfa aerial parts inhibited lipopolysaccharide (LPS)-stimulated immune responses more than ether, butanol, or water soluble extracts. Treatment with 1 μg/mL LPS increased nitrite concentrations to 44.3 μM in RAW267.4 macrophages, but it was reduced to 10.6 μM by adding 100 μg/mL chloroform extract. LPS treatment also increased the concentrations of tumor necrosis factor-α, interleukin (IL)-6, and IL-1β to 41.3, 11.6, and 0.78 ng/mL in culture supernatants of the cells, but these cytokine levels decreased to 12.5, 3.1, and 0.19 ng/mL, respectively, by pretreating with 100 μg/mL of the extract. ICR mice injected with LPS (30 mg/kg body weight) alone showed a 0% survival rate after 48 h of the injection, but 48-h survival of the mice increased to 60% after oral administration of the extract. Subfractions of the chloroform extract markedly suppressed LPS-mediated activation of the extracellular signal-regulated kinase and nuclear factor kappa-B. Cinnamic acid derivatives and fatty acids were found to be active constituents of the extract. This research demonstrated that alfalfa aerial parts exert anti-inflammatory activity and may be useful as a functional food for the prevention of inflammatory disorders.

  2. Expression of an alfalfa (Medicago sativa L.) peroxidase gene in transgenic Arabidopsis thaliana enhances resistance to NaCl and H2O2.

    Science.gov (United States)

    Teng, K; Xiao, G Z; Guo, W E; Yuan, J B; Li, J; Chao, Y H; Han, L B

    2016-05-23

    Peroxidases (PODs) are enzymes that play important roles in catalyzing the reduction of H2O2 and the oxidation of various substrates. They function in many different and important biological processes, such as defense mechanisms, immune responses, and pathogeny. The POD genes have been cloned and identified in many plants, but their function in alfalfa (Medicago sativa L.) is not known, to date. Based on the POD gene sequence (GenBank accession No. L36157.1), we cloned the POD gene in alfalfa, which was named MsPOD. MsPOD expression increased with increasing H2O2. The gene was expressed in all of the tissues, including the roots, stems, leaves, and flowers, particularly in stems and leaves under light/dark conditions. A subcellular analysis showed that MsPOD was localized outside the cells. Transgenic Arabidopsis with MsPOD exhibited increased resistance to H2O2 and NaCl. Moreover, POD activity in the transgenic plants was significantly higher than that in wild-type Arabidopsis. These results show that MsPOD plays an important role in resistance to H2O2 and NaCl.

  3. Co-downregulation of the hydroxycinnamoyl-CoA:shikimate hydroxycinnamoyl transferase and coumarate 3-hydroxylase significantly increases cellulose content in transgenic alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Tong, Zongyong; Li, Heng; Zhang, Rongxue; Ma, Lei; Dong, Jiangli; Wang, Tao

    2015-10-01

    Lignin is a component of the cell wall that is essential for growth, development, structure and pathogen resistance in plants, but high lignin is an obstacle to the conversion of cellulose to ethanol for biofuel. Genetically modifying lignin and cellulose contents can be a good approach to overcoming that obstacle. Alfalfa (Medicago sativa L.) is rich in lignocellulose biomass and used as a model plant for the genetic modification of lignin in this study. Two key enzymes in the lignin biosynthesis pathway-hydroxycinnamoyl -CoA:shikimate hydroxycinnamoyl transferase (HCT) and coumarate 3-hydroxylase (C3H)-were co-downregulated. Compared to wild-type plants, the lignin content in the modified strain was reduced by 38%, cellulose was increased by 86.1%, enzyme saccharification efficiency was increased by 10.9%, and cell wall digestibility was increased by 13.0%. The modified alfalfa exhibited a dwarf phenotype, but normal above ground biomass. This approach provides a new strategy for reducing lignin and increasing cellulose contents and creates a new genetically modified crop with enhanced value for biofuel.

  4. Co-transforming bar and CsALDH genes enhanced resistance to herbicide and drought and salt stress in transgenic alfalfa (Medicago sativa L.

    Directory of Open Access Journals (Sweden)

    Zhen eDuan

    2015-12-01

    Full Text Available Drought and high salinity are two major abiotic factors that restrict the productivity of alfalfa. By application of the Agrobacterium-mediated transformation method, an oxidative responsive gene, CsALDH12A1, from the desert grass Cleistogenes songorica together with the bar gene associated with herbicide resistance, were co-transformed into alfalfa (Medicago sativa L.. From the all 90 transformants, 16 were positive as screened by spraying 1 mL L-1 10% Basta solution and molecularly diagnosis using PCR. Real-time PCR analysis indicated that drought and salt stress induced high CsALDH expression in the leaves of the transgenic plants. The CsALDH expression levels under drought (15 d and salt stress (200 mM NaCl were 6.11 and 6.87 times higher than in the control plants, respectively. In comparison to the WT plants, no abnormal phenotypes were observed among the transgenic plants, which showed significant enhancement of tolerance to 15 d of drought and 10 d of salinity treatment. Evaluation of the physiological and biochemical indices during drought and salt stress of the transgenic plants revealed relatively lower Na+ content and higher K+ content in the leaves relative to the WT plants, a reduction of toxic on effects and maintenance of osmotic adjustment. In addition, the transgenic plants could maintain a higher relative water content (RWC level, higher shoot biomass, fewer changes in the photosystem, decreased membrane injury, and a lower level of osmotic stress. These results indicate that the co-expression of the introduced bar and CsALDH genes enhanced the herbicide, drought and salt tolerance of alfalfa and therefore can potentially be used as a novel genetic resource for the future breeding programs to develop new cultivars.

  5. Effect of arbuscular mycorrhizal fungi (AMF) on heavy metal tolerance of alfalfa (Medicago sativa L.) and oat (Avena sativa L.) on a sewage-sludge treated soil; Bedeutung der arbuskulaeren Mykorrhiza (AM) fuer die Schwermetalltoleranz von Luzerne (Medicago sativa L.) und Hafer (Avena sativa L.) auf einem klaerschlammgeduengten Boden

    Energy Technology Data Exchange (ETDEWEB)

    Ricken, B. [Institut fuer Pflanzenernaehrung, Giessen Univ. (Germany); Hoefner, W. [Institut fuer Pflanzenernaehrung, Giessen Univ. (Germany)

    1996-10-01

    In pot experiments with a sewage sludge treated soil, the influence of two arbuscular mycorrhizal fungi (AMF) isolates of Glomus sp. (T6 and D13) on plant growth and on the uptake of heavy metals by alfalfa (Medicago sativa L.) and oat (Avena sativa L.) was investigated. Alfalfa showed an increase of biomass with mycorrhizal infection only to a small extent. In oat AMF inoculation increased the growth of both root and shoot by up to 70% and 55% respectively. Mycorrhization raised the P-content and -uptake in alfalfa, but not in oat, in both roots and shoots. Mycorrhizal alfalfa showed lower Zn-, Cd- and Ni-contents and uptake in roots and shoots. The root length was significantly decreased in mycorrhizal alfalfa plants (up to 38%). The translocation of heavy metals into the shoot of mycorrhizal alfalfa was slightly increased. Mycorrhizal infection of oat led to higher concentrations of Zn, Cd and Ni in the root but to less Zn in the shoot. The translocation of heavy metals to the oat shoot was clearely decreased by mycorrhizal colonisation. This may be based on the ability of fungal tissues to complex heavy metals at the cell walls, thus excluding metals from the shoot. This conclusion is supported by the enhanced root length (up to 78%) of mycorrhizal oat plants in this experiment. The mycorrhizal infection seemed to protect plants against heavy metal pollution in soils. It was obvious that different host plants reacted in different ways. (orig.) [Deutsch] In Gefaessversuchen mit einem klaerschlammgeduengten Boden wurde der Einfluss der arbuskulaeren Mykorrhiza (AM)-Pilzisolate von Glomus sp. (T6 und D13) auf Pflanzenwachstum und Schwermetall (SM)-aufnahme von Luzerne (Medicago sativa L.) und Hafer (Avena sativa L.) untersucht. Das Wachstum von Luzerne wurde durch eine Mykorrhizierung nicht signifikant beeinflusst. Bei Hafer foerderte eine AM-Inokulation mit T6 das Wachstum von Wurzel und Spross bis zu 70% bzw. 55%, zur Reife aber ergab sich gleicher Sprossertrag

  6. TCP在种植苜蓿土壤中的降解研究%Degradation of TCP in Soil Planted with Alfalfa (Medicago sativa L.)

    Institute of Scientific and Technical Information of China (English)

    丁克强

    2010-01-01

    [目的]研究TCP在苜蓿种植土壤中的降解作用,为氯酚类物质污染土壤生物修复技术的实际应用提供依据.[方法]利用玻璃房盆栽试验,研究苜蓿对土壤中2,4,6-三氯酚(TCP)污染的修复作用以及苜蓿的生长情况和TCP对土壤多酚氧化酶、脱氢酶和过氧化氢酶活性的影响.[结果]苜蓿经过75 d的生长后,在低、中、高3个浓度处理中,土壤中TCP含量均在15 d内迅速降低,随后降低速度逐渐变缓;在苜蓿生长30d时,3个处理的苜蓿鲜重与对照间无显著差异(P<0.05),而在生长75 d时,各处理的苜蓿鲜重明显对照低(P<0.05),表明土壤中TCP对苜蓿的生长具有抑制作用;苜蓿能显著提高土壤中多酚氧化酶、脱氢酶和过氧化氢酶的活性,从而提高了土壤植物和微生物对污染物的降解能力.[结论]苜蓿能促进土壤酶活性的提高,促进土壤中有机物的降解,从而可以利用苜蓿进行TCP污染土壤的植物修复.%[Objective]The research aimed to study the degradation of 2,4,6-trichlorophenol(TCP)in soil planted with alfalfa(Medicago sativa L.),as well as to provide references for the Chlorophenols phytoremediation technology in the practical application.[Method]By the use of pot culture experiment in greenhouse,the phytoremediation effect of alfalfa on TCP-contaminated soil,the growth conditions of alfalfa,as well as the effect of TCP on the activity of soil polyphenol oxidase,dehydrogenase and catalase were studied.[Result]After the alfalfa was grown for 75 d,the TCP content in soil of three different concentrations treatments(low,middle and high)decreased dramatically within 15 d,and then the decreasing rate was gradually slow;on the 30th d of cultivation,the fresh weight of treated alfalfa showed no significant difference with the control(P<0.05),indicating that TCP in soil had inhibition effect on the growth of alfalfa;alfalfa could significantly enhance the activities of polyphenol oxidase

  7. Disponibilidade hídrica relacionada ao conteúdo de nitrogênio e à produtividade da alfafa (Medicago sativa L. Water availability on yield and nitrogen contents of alfalfa (Medicago sativa L.

    Directory of Open Access Journals (Sweden)

    Wladecir Salles de Oliveira

    2003-12-01

    resultado do aumento da transpiração.Variation in the abundance of 13C and biological nitrogen fixation in legume plants such as alfalfa (Medicago sativa L. can be used in cultivar selection programs allowing a better understanding of the physiological processes related to water use, photosynthesis and biological nitrogen fixation and their interdependence. This would supply data for selection programs for the improvement of dry matter yield (DM, water use efficiency (WUE and biomass quality. Thus evaluation of the plant under contrasting conditions becomes necessary, therefore in this study, the plants were evaluated under rainfall and irrigated conditions in lysimeters. In this study, 12 and 6 alfalfa cultivars was evaluated respectively in two experiments installed in lysimeters by split-plot statistical design under constant irrigation and regime of rains. The results showed the existence of a complex interdependence between the agronomic characteristics of the alfalfa cultivars. Under controlled conditions the alfalfa responded positively to irrigation, in relation to both quantitative and qualitative characteristics. The cultivars Crioula Chilena and Crioula Brasileira showed the best results. In the first evaluation (after 6 months correlations between carbon isotopic discrimination (CID, biological nitrogen fixation (BNF, dry matter yield (DM and water use efficiency (WUE were not significant. In the second evaluation (after 1 year, under irrigated conditions CID was negatively correlated with DM (-0.92**, WUE (-0.94** and BNF (-0.79*. BNF was positively correlated with DM (0.93** and WUE (0.87*. Under non-irrigated conditions correlation between these parameters was not significant. There exists a tendency for a positive correlation between DM and CID in studies with C3 plants that can be altered when water is limiting, root development is limited or when contrasting cultivars are used. If a positive correlation is maintained, the possibility of increasing the

  8. Cloning and expression of 1-aminocyclopropane-1-carboxylate oxidase cDNA induced by thidiazuron during somatic embryogenesis of alfalfa (Medicago sativa).

    Science.gov (United States)

    Feng, Bi-Hong; Wu, Bei; Zhang, Chun-Rong; Huang, Xia; Chen, Yun-Feng; Huang, Xue-Lin

    2012-01-15

    Embryogenic callus (EC) induced from petioles of alfalfa (Medicago sativa L. cv. Jinnan) on B5h medium turned green, compact and non-embryogenic when the kinetin (KN) in the medium was replaced partially or completely by thidiazuron (TDZ). The application of CoCl₂, which is an inhibitor of 1-aminocyclopropane-1-carboxylate oxidase (ACO), counteracted the effect of TDZ. Ethylene has been shown to be involved in the modulation of TDZ-induced morphogenesis responses. However, very little is known about the genes involved in ethylene formation during somatic embryogenesis (SE). To investigate whether ethylene mediated by ACO is involved in the effect of TDZ on inhibition of embryogenic competence of the alfalfa callus. In this study we cloned full-length ACO cDNA from the alfalfa callus, named MsACO, and observed changes in this gene expression during callus formation and induction of SE under treatment with TDZ or TDZ plus CoCl₂. RNA blot analysis showed that during the EC subcultural period, the expression level of MsACO in EC was significantly increased on the 2nd day, rose to the highest level on the 8th day and remained at this high level until the 21st day. However, the ACO expression in the TDZ (0.93 μM)-treated callus was higher than in the EC especially on the 8th day. Moreover the ACO expression level increased with increasing TDZ concentration during the subcultural/maintenance period of the callus. It is worth noting that comparing the treatment with TDZ alone, the treatment with 0.93 μM TDZ plus 50 μM CoCl₂ reduced both of the ACO gene expressions and ACO activity in the treated callus. These results indicate that the effect of TDZ could be counteracted by CoCl₂ either on the ACO gene expression level or ACO activity. Thus, a TDZ inhibitory effect on embryogenic competence of alfalfa callus could be mediated by ACO gene expression.

  9. Improvement of in vitro embryo maturation, plantlet regeneration and transformation efficiency from alfalfa (Medicago sativa L.) somatic embryos using Cuscuta campestris extract.

    Science.gov (United States)

    Amini, Massoume; Deljou, Ali; Nabiabad, Haidar Saify

    2016-07-01

    Developmental deficiency of somatic embryos and regeneration to plantlets, especially in the case of transformation, are major problems of somatic embryo regeneration in alfalfa. One of the ways to overcome these problems is the use of natural plant regulators and nutrients in the culture medium of somatic embryos. For investigating the influence of Cuscuta campestris extract on the efficiency of plant regeneration and transformation, chimeric tissue type plasminogen activator was transferred to explants using Agrobacterium tumefaciens, and transgenic plants were recovered using medium supplemented with different concentration of the extract. Transgenic plants were analyzed by PCR and RT-PCR. Somatic embryos of Medicago sativa L. developed into plantlets at high frequency level (52 %) in the maturation medium supplemented with 50 mg 1(-1)C. campestris extract as compared to the medium without extract (26 %). Transformation efficiency was 29.3 and 15.2 % for medium supplemented with dodder extract and without the extract, respectively. HPLC and GC/MS analysis of the extract indicated high level of ABA and some compounds such as Phytol, which can affect the somatic embryo maturation. The antibacterial assay showed that the extract was effective against some strains of A. tumefaciens. These results have provided a scientific basis for using of C. campestris extract as a good natural source of antimicrobial agents and plant growth regulator as well, that can be used in tissue culture of transgenic plants.

  10. In vivo characterization of the effects of abscisic acid and drying protocols associated with the acquisition of desiccation tolerance in alfalfa (Medicago sativa L.) somatic embryos.

    Science.gov (United States)

    Sreedhar, Lekha; Wolkers, Willem F; Hoekstra, Folkert A; Bewley, J Derek

    2002-04-01

    Although somatic embryos of alfalfa (Medicago sativa L.) had acquired some tolerance to desiccation at the cotyledonary stage of development (22 d after plating), additional culturing in 20 microm abscisic acid (ABA) for 8 d induced greater desiccation tolerance, as determined by increased germination. Compared with fast drying, slow drying of the ABA-treated embryos improved desiccation tolerance. However, slow drying of non-ABA-treated embryos led to the complete loss of germination capacity, while some fast-dried embryos survived. An electron paramagnetic resonance spin probe technique and in vivo Fourier transform infrared microspectroscopy revealed that cellular membrane integrity and a-helical protein secondary structure were maintained during drying in embryos cultured in media enriched with 20 microM ABA, but not in embryos cultured in the absence of ABA. Slow-dried, non-ABA-treated embryos had low oligosaccharide to sucrose ratios, an increased proportion of beta-sheet protein secondary structures and broad membrane phase transitions extending over a temperature range of more than 60 degrees C, suggestive of irreversible phase separations. The spin probe study showed evidence of imbibitional damage, which could be alleviated by prehydration in humid air. These observations emphasize the importance of appropriate drying and prehydration protocols for the survival and storage of somatic embryos. It is suggested that ABA also plays a role in suppressing metabolism, thus increasing the level of desiccation tolerance; this is particularly evident under stressful conditions such as slow drying.

  11. Absorption of SO/sub 2/ by pecan (Carya illinoensis (Wang) K. Koch) and alfalfa (Medicago sativa L. ) and its effect on net photosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Sisson, W.B.; Booth, J.A.; Throneberry, G.O.

    1981-06-01

    Absorption rates of SO/sub 2/ by pecan (Carya illinoensis (Wang) K. Koch) leaflets exposed to 2.6, 5.2, and 7.8 mg SO/sub 2/ m/sup -3/ were measured over a 2 h period. SO/sub 2/ was rapidly absorbed by the leaflets in all treatments during the initial 30-50 min; the rate of uptake decreased to a rather constant level thereafter. Total SO/sub 2/ absorbed during the 2 h period was 15.6, 25.6, and 38.9 nmol cm/sup -2/ for the low, medium, and high SO/sub 2/ concentrations, respectively. Reductions in net photosynthetic rates were proportional to ambient SO/sub 2/ concentrations and total SO/sub 2/ absorbed. Partial photosynthetic recovery occurred in all treatments during a 2 hr post-treatment period and full recovery occurred during a 12 h dark period. Exposure to SO/sub 2/ resulted in slight increases in stomatal and boundary layer resistances to CO/sub 2/ and substantial increases in residual resistances. Absorption rates of SO/sub 2/ by alfalfa (Medicago sativa L.) exposed to 5.2 mg SO/sub 2/ m/sup -3/ for 1 h were approximately double those of pecan exposed to the same ambient SO/sub 2/ concentration. Alfalfa net photosynthetic rates were reduced 74% after 1 h exposure to 5.2 mg SO/sub 2/ m/sup -3/ while a depression of 42% occurred in pecan.

  12. Assessing of the contributions of pod photosynthesis to carbon acquisition of seed in alfalfa (Medicago sativa L.)

    Science.gov (United States)

    Zhang, Wenxu; Mao, Peisheng; Li, Yuan; Wang, Mingya; Xia, Fangshan; Wang, Hui

    2017-01-01

    The distribution of carbon from a branch setting pod in alfalfa was investigated during the seed development of seeds to determine the relative contribution of pod and leaf photoassimilates to the total C balance and to investigate the partitioning of these photoassimilates to other plant organs. A 13Clabeling procedure was used to label C photoassimilates of pods and leaves in alfalfa, and the Δ13C values of a pod, leaves, a section of stem and roots were measured during seed development on day 10, 15, 20 and 25 after labeling of the pod. The results showed that the alfalfa pod had photosynthetic capacity early in the development of seeds, and that pod photosynthesis could provide carbon to alfalfa organs including seeds, pods, leaves, stems and roots, in addition to leaf photosynthesis. Photosynthesis in the pod affected the total C balance of the alfalfa branch with the redistribution of a portion of pod assimilates to other plant organs. The assimilated 13C of the pod was used for the growth requirements of plant seeds and pods. The requirements for assimilated C came primarily from the young pod in early seed development, with later requirements provided primarily from the leaf. PMID:28169330

  13. Assessing of the contributions of pod photosynthesis to carbon acquisition of seed in alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Zhang, Wenxu; Mao, Peisheng; Li, Yuan; Wang, Mingya; Xia, Fangshan; Wang, Hui

    2017-02-07

    The distribution of carbon from a branch setting pod in alfalfa was investigated during the seed development of seeds to determine the relative contribution of pod and leaf photoassimilates to the total C balance and to investigate the partitioning of these photoassimilates to other plant organs. A (13)Clabeling procedure was used to label C photoassimilates of pods and leaves in alfalfa, and the Δ(13)C values of a pod, leaves, a section of stem and roots were measured during seed development on day 10, 15, 20 and 25 after labeling of the pod. The results showed that the alfalfa pod had photosynthetic capacity early in the development of seeds, and that pod photosynthesis could provide carbon to alfalfa organs including seeds, pods, leaves, stems and roots, in addition to leaf photosynthesis. Photosynthesis in the pod affected the total C balance of the alfalfa branch with the redistribution of a portion of pod assimilates to other plant organs. The assimilated (13)C of the pod was used for the growth requirements of plant seeds and pods. The requirements for assimilated C came primarily from the young pod in early seed development, with later requirements provided primarily from the leaf.

  14. Overexpression of GsZFP1 enhances salt and drought tolerance in transgenic alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Tang, Lili; Cai, Hua; Ji, Wei; Luo, Xiao; Wang, Zhenyu; Wu, Jing; Wang, Xuedong; Cui, Lin; Wang, Yang; Zhu, Yanming; Bai, Xi

    2013-10-01

    GsZFP1 encodes a Cys2/His2-type zinc-finger protein. In our previous study, when GsZFP1 was heterologously expressed in Arabidopsis, the transgenic Arabidopsis plants exhibited enhanced drought and cold tolerance. However, it is still unknown whether GsZFP1 is also involved in salt stress. GsZFP1 is from the wild legume Glycine soja. Therefore, the aims of this study were to further elucidate the functions of the GsZFP1 gene under salt and drought stress in the forage legume alfalfa and to investigate its biochemical and physiological functions under these stress conditions. Our data showed that overexpression of GsZFP1 in alfalfa resulted in enhanced salt tolerance. Under high salinity stress, greater relative membrane permeability and malondialdehyde (MDA) content were observed and more free proline and soluble sugars accumulated in transgenic alfalfa than in the wild-type (WT) plants; in addition, the transgenic lines accumulated less Na(+) and more K(+) in both the shoots and roots. Overexpression of GsZFP1 also enhanced the drought tolerance of alfalfa. The fold-inductions of stress-responsive marker gene expression, including MtCOR47, MtRAB18, MtP5CS, and MtRD2, were greater in transgenic alfalfa than those of WT under drought stress conditions. In conclusion, the transgenic alfalfa plants generated in this study could be used for farming in salt-affected as well as arid and semi-arid areas.

  15. Ensifer, Phyllobacterium and Rhizobium species occupy nodules of Medicago sativa (alfalfa) and Melilotus alba (sweet clover) grown at a Canadian site without a history of cultivation.

    Science.gov (United States)

    Bromfield, E S P; Tambong, J T; Cloutier, S; Prévost, D; Laguerre, G; van Berkum, P; Thi, T V Tran; Assabgui, R; Barran, L R

    2010-02-01

    Phage-resistant and -susceptible bacteria from nodules of alfalfa and sweet clover, grown at a site without a known history of cultivation, were identified as diverse genotypes of Ensifer, Rhizobium and Phyllobacterium species based on sequence analysis of ribosomal (16S and 23S rRNA) and protein-encoding (atpD and recA) genes, Southern hybridization/RFLP and a range of phenotypic characteristics. Among phage-resistant bacteria, one genotype of Rhizobium sp. predominated on alfalfa (frequency approximately 68 %) but was recovered infrequently ( approximately 1 %) from sweet clover. A second genotype was isolated infrequently only from alfalfa. These genotypes fixed nitrogen poorly in association with sweet clover and Phaseolus vulgaris, but were moderately effective with alfalfa. They produced a near-neutral reaction on mineral salts agar containing mannitol, which is atypical of the genus Rhizobium. A single isolate of Ensifer sp. and two of Phyllobacterium sp. were recovered only from sweet clover. All were highly resistant to multiple antibiotics. Phylogenetic analysis indicated that Ensifer sp. strain T173 is closely related to, but separate from, the non-symbiotic species 'Sinorhizobium morelense'. Strain T173 is unique in that it possesses a 175 kb symbiotic plasmid and elicits ineffective nodules on alfalfa, sweet clover, Medicago lupulina and Macroptilium atropurpureum. The two Phyllobacterium spp. were non-symbiotic and probably represent bacterial opportunists. Three genotypes of E. meliloti that were symbiotically effective with alfalfa and sweet clover were encountered infrequently. Among phage-susceptible isolates, two genotypes of E. medicae were encountered infrequently and were highly effective with alfalfa, sweet clover and Medicago polymorpha. The ecological and practical implications of the findings are discussed.

  16. Regeneration of foreign genes co-transformed plants of Medicago sativa L by Agrobacterium rhizogenes

    Institute of Scientific and Technical Information of China (English)

    吕德扬; 曹学远; 唐顺学; 田霞

    2000-01-01

    Gene encoding sulphur amino acid-rich protein (HNP) and rol genes were transferred into Medicago sativa L (alfalfa) mediated by Agrobacterium tumafeciens. Regeneration of trans-genie plants was induced successfully from hairy root tissue of cotyledon in alfalfa. Cotyledon tissues were an ideally transformed recipient. There was a negative correlation between age of hairy roots and embryogenesis frequency in alfalfa. Production of co-transformed plants with greater yield and super quality was important for development of new alfalfa varieties.

  17. Regeneration of foreign genes co-transformed plants of Medicago sativa L by Agrobacterium rhizogenes

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Gene encoding sulphur amino acid-rich protein (HNP) and rol genes were transferred into Medicago sativa L (alfalfa) mediated by Agrobacterium tumafeciens. Regeneration of transgenic plants was induced successfully from hairy root tissue of cotyledon in alfalfa. Cotyledon tissues were an ideally transformed recipient. There was a negative correlation between age of hairy roots and embryogenesis frequency in alfalfa. Production of co-transformed plants with greater yield and super quality was important for development of new alfalfa varieties.

  18. Evaluation of microbial biomass C and N content of the soils cultivated with vetch (Vicia sativa L. and alfalfa (Medicago sativa L.

    Directory of Open Access Journals (Sweden)

    İlyas Bolat

    2016-01-01

    Full Text Available Legume forage crops have the ability of retaining free nitrogen in the air through symbiotic Rhizobium bacteria found in their roots. Additionally, microbial biomass (MB–an essential living component of soil and a significant factor influencing plant nutrient dynamics–is considered to be accurate indicator of soil’s biological condition. Given the aforementioned aspects, soil MB C (Cmic and MB N (Nmic of different legume forage crops were investigated in this study. Soil samples were taken in order to identify certain physical and chemical characteristics of the soil using volume cylinders (0 – 6.5 cm depth from Vicia sativa L. (VSP and Medicago sativa L. planted (MSP areas. To determine the Cmic and Nmic contents, topsoil samples were also taken from 0 – 6.5 cm depth. Cmic and Nmic contents were identified using chloroform – fumigation – extraction method. There was no statistical significance for particle density, bulk density, electrical conductivity, CaCO3 %, and decomposition ratio (Corg/Ntotal of the VSP and MSP soil (P > 0.05. However, some other soil characteristics such as temperature, porosity, sand, silt and clay contents, pH, organic C and total N differed significantly (P < 0.05. Compared to VSP soil, the Cmic contents were determined to be 27 % higher (P < 0.05 in MSP soil. In VSP soil, the soil Nmic content ranged from 83.38 µg g-1 to 124.67 µg g-1, while it ranged from 91.62 µg g-1 to 187.07 µg g-1 in MSP soil. The Nmic content of the MSP soil was observed to be approximately 35 % higher than VSP soil, and a statistically significant difference (P < 0.05 was noticed between the two. Moreover, a significant positive correlation was found not only between the Cmic and organic C contents (r = 0.667; P < 0.05 but also between the Nmic and total N contents of MSP and VSP soil (r = 0.881; P < 0.01. The results of the study revealed that soil Cmic and Nmic values differ as the types of planted legume forage crops

  19. Circulating fluidized bed combustion product addition to acid soil: alfalfa (Medicago sativa L.) composition and environmental quality.

    Science.gov (United States)

    Chen, Liming; Dick, Warren A; Kost, David

    2006-06-28

    To reduce S emissions, petroleum coke with a high concentration of S was combusted with limestone in a circulating fluidized bed (CFB) boiler. The combustion process creates a bed product that has potential for agricultural uses. This CFB product is often alkaline and enriched in S and other essential plant nutrients, but also contains high concentrations of Ni and V. Agricultural land application of CFB product is encouraged, but little information is available related to plant responses and environmental impacts. CFB product and agricultural lime (ag-lime) were applied at rates of 0, 0.5, 1.0, and 2.0 times the soil's lime requirement (LR) to an acidic soil (Wooster silt loam). The 2.0x LR application rate of CFB product was equivalent to 67.2 Mg ha(-1). Alfalfa yield was increased 4.6 times by CFB product and 3.8 times by ag-lime compared to untreated control. Application of CFB product increased the concentration of V in soil and alfalfa tissue, but not in soil water, and increased the concentration of Ni in soil and soil water, but not in alfalfa tissue. However, these concentrations did not reach levels that might cause environmental problems.

  20. Contrasting pattern of somatic and zygotic embryo development in alfalfa (Medicago sativa L.) as revealed by scanning electron microscopy.

    Science.gov (United States)

    Xu, N; Bewley, J D

    1992-06-01

    Scanning electron microscopy has been used to investigate the morphological changes occurring during the development of alfalfa somatic embryos. Embryos were initiated from callus, transferred to suspension culture and matured on solid agar medium. This developmental pattern was compared to that of zygotic embryos developing in ovulo. Somatic embryos begin as distinct pro-embryos within the callus tissue pieces placed in suspension culture. They become globular and heart-shaped while on solid agar medium and then undergo cotyledon elongation and maturation. Somatic embryos develop comparatively slower at early stages of development and faster at the later stages than zygotic embryos. They lack a well-defined suspensor and have a very rough, poorly-differentiated epidermis, the first layer of which is lost after pro-embryo formation. The cotyledons of somatic embryos are multiple and poorlydeveloped; there appears to be a correlation between the amount of surface roughness of the developing embryo and the extent to which polycotyledony occurs.

  1. Investigating the Effect of Phosphorus, Potassium and Weed Management on Forage and Seed Yield of Alfalfa Ecotypes (Medicago sativa L.

    Directory of Open Access Journals (Sweden)

    Ali Reza Heidarian

    2012-09-01

    Full Text Available In order to investigate fertilizing and weed management effects on forage and seed yield of alfalfa ecotypes, a field trial was conducted during 2008-2009 growing season at Khorasan Agricultural and Natural Resource Research Center, Mashhad-Iran. Alfalfa ecotypes including (Ghareghozlo, Hoakmabad, Malekkandi, Kozre, Faminin, Galebani, Rahnani, Shorkat, Chaleshtar, Ghareaghaj, Gharoghlogh, Ordobad, Sedighan, Silvana, Sahandava, Ghahavand, Mohajerankaraj and Mashhad were allocated to main plots; sub plots consisted of two levels of none fertilizing and fertilization treatments using simultaneous application of potassium sulphate and phosphate triple at rates of 150 and 350 K/ha, respectively and sub-sub plots were allocated to weeding and none weeding treatments based on a complete randomized block design in a splitsplit- plot scheme with three replicates. Results showed that the effect of ecotype on forage yield was not significant. Gharoghlogh and Silvana produced the highest (18270 kg/ha and the lowest (14630 kg/ha green forage yield, respectively at both cuttings (first and second cuts. The interaction of fertilization and weeding on forage yield was significant (p<0.01. On the other hand, with application of fertilizer, forage yield 11.74% was increased and it was enhanced 26.93% by manual weeding. Furthermore, results revealed that ecotype fertilizer interaction was significant (p<0.05 for weed dry weight. Ecotype weeding interaction was significant (p<0.05 for number of seed per pod and seed weight (p<0.01. In addition, fertilizer weeding interaction was significant (p<0.05 for number of seed per plant. Among the treatments, highest number of seed per plant was produced by fertilizer and weeding treatment (2734 and the lowest one was obtained by non-fertilizer and non-weeding treatment (559.5.

  2. Structural, thermal, and anti-inflammatory properties of a novel pectic polysaccharide from alfalfa (Medicago sativa L.) stem.

    Science.gov (United States)

    Chen, Lei; Liu, Jie; Zhang, Yaqiong; Dai, Bona; An, Yuan; Yu, Liangli Lucy

    2015-04-01

    A pectic polysaccharide (APPS) was purified from the cold alkali extract of alfalfa stem and characterized to be a rhamnogalacturonan I (RG-I) type pectin with the molecular weight of 2.38 × 10(3) kDa and a radius of 123 nm. The primary structural analysis indicated that APPS composed of a →2)-α-l-Rhap-(1→4)-α-d-GalpA-(1→ backbone with 12% branching point at C-4 of Rhap forming side chains by l-arabinosyl and d-galactosyl oligosaccharide units. Transmission electron microscopy (TEM) analysis revealed a primary linear-shaped structure with a few branches in its assembly microstructures. The thermal decomposition evaluation revealed the stability of APPS with an apparent activation energy (Ea) of 226.5 kJ/mol and a pre-exponential factor (A) of 2.10 × 10(25)/s, whereas its primary degradation occurred in the temperature range from 215.6 to 328.0 °C. In addition, APPS showed significant anti-inflammatory effect against mRNA expressions of the pro-inflammatory cytokine genes, especially for IL-1β, suggesting its potential utilization in functional foods and dietary supplement products.

  3. A novel alkaline hemicellulosic heteroxylan isolated from alfalfa (Medicago sativa L.) stem and its thermal and anti-inflammatory properties.

    Science.gov (United States)

    Chen, Lei; Liu, Jie; Zhang, Yaqiong; Niu, Yuge; Dai, Bona; Yu, Liangli Lucy

    2015-03-25

    A novel hemicellulosic polysaccharide (ACAP) was purified from the cold alkali extraction of alfalfa stems and characterized as a heteroxylan with a weight-average molecular weight of 7.94 × 10(3) kDa and a radius of 58 nm. Structural analysis indicated that ACAP consisted of a 1,4-linked β-D-Xylp backbone with 4-O-MeGlcpA and T-L-Araf substitutions at O-2 and O-3 positions, respectively. Transmission electron microscopy (TEM) examination revealed the entangled chain morphology of ACAP molecules. The evaluation of thermal degradation property revealed a primary decomposition temperature range of 238.8-314.0 °C with an apparent activation energy (Ea) and a pre-exponential factor (A) of 220.0 kJ/mol and 2.81 × 10(24)/s, respectively. ACAP also showed significant inhibitory activities on IL-1β, IL-6, and COX-2 gene expressions in cultured RAW 264.7 mouse macrophage cells. These results suggested the potential utilization of ACAP in functional foods and dietary supplement products.

  4. Stress-related phenomena and detoxification mechanisms induced by common pharmaceuticals in alfalfa (Medicago sativa L.) plants.

    Science.gov (United States)

    Christou, Anastasis; Antoniou, Chrystalla; Christodoulou, Charalampia; Hapeshi, Evroula; Stavrou, Ioannis; Michael, Costas; Fatta-Kassinos, Despo; Fotopoulos, Vasileios

    2016-07-01

    Pharmaceutically active compounds (PhACs) have been recently shown to exert phytotoxic effects. The present study explores the uptake, systemic translocation, and abiotic stress responses and detoxification mechanisms induced by the exposure of alfalfa plants grown in sand under greenhouse conditions to four common, individually applied PhACs (10μgL(-1)) (diclofenac, sulfamethoxazole, trimethoprim, 17a-ethinylestradiol) and their mixture. Stress physiology markers (lipid peroxidation, proline, H2O2 and NO content, antioxidant activity assays) and gene expression levels of key plant detoxification components (including glutathione S-transferases, GST7, GST17; superoxide dismutases, CuZnSOD, FeSOD; proton pump, H(+)-ATP, and cytochrome c oxidase, CytcOx), were evaluated. PhACs were detected in significantly higher concentrations in roots compared with leaves. Stress related effects, manifested via membrane lipid peroxidation and oxidative burst, were local (roots) rather than systemic (leaves), and exacerbated when the tested PhACs were applied in mixture. Systemic accumulation of H2O2 in leaves suggests its involvement in signal transduction and detoxification responses. Increased antioxidant enzymatic activities, as well as upregulated transcript levels of GST7, GST17, H(+)-ATPase and CytcOx, propose their role in the detoxification of the selected PhACs in plants. The current findings provide novel biochemical and molecular evidence highlighting the studied PhACs as an emerging abiotic stress factor, and point the need for further research on wastewater flows under natural agricultural environments.

  5. Cloning and function analysis of an alfalfa (Medicago sativa L.) zinc finger protein promoter MsZPP.

    Science.gov (United States)

    Li, Yan; Sun, Yan; Yang, Qingchuan; Kang, Junmei; Zhang, Tiejun; Gruber, Margaret Yvonne; Fang, Feng

    2012-08-01

    A 1272 bp upstream sequence of MsZFN gene was cloned from alfalfa, which was designed as MsZPP (Genbank accession number: FJ 161979.2) using an adaptor-mediated genome walking method. A sole transcription start site was located 69 bp upstream of the translation start site. Its pattern of expression included roots, stem vascular tissues, floral reproductive organs, and leaves, but the promoter did not express in seeds, petals or sepals. Transcription levels can be stimulated by dark, MeJA, and IAA. However, GUS fusion activities had no change by treatments of GA, ABA, drought and high salt for 3 days. Deletion analysis revealed that all sections of the promoter can drive gus gene expression in the root, stem, leaves and floral reproductive organs; however, only fragments longer than the -460 bp promoter can stimulate strong gus gene expression in these organs. In addition, the -460 bp promoter fragment can drive gus expression not only in the vascular tissue, but also in leaf guard cells. The results suggest that the promoter MsZPP plays roles in the regulation of transgene expression, particularly due to its darkness, MeJA, and IAA responsiveness.

  6. Ethyl acetate extracts of alfalfa (Medicago sativa L. sprouts inhibit lipopolysaccharide-induced inflammation in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Chen Miaw-Ling

    2009-07-01

    Full Text Available Abstract This study aimed to investigate if food components that exert anti-inflammatory effects may be used for inflammatory disorders by examining alfalfa sprout ethyl acetate extract (ASEA. The cytokine profile and life span of BALB/c mice with acute inflammation after intra-peritoneal (ip injection of 15 mg/kg BW lipopolysaccharide (LPS were determined. The results showed that the life span of LPS-induced inflammatory mice were negatively correlated with serum levels of TNF-α, IL-6, and IL-1β at 9 hr after LPS-injection, which indicated that suppressing these cytokines in the late phase of inflammation may be beneficial for survival. The in vitro experiment then showed that ASEA significantly reduced IL-6 and IL-1β production and the NF-κB trans-activation activity of mitogen-stimulated RAW264.7 cells. To further evaluate the anti-inflammatory effects of ASEA in vivo, BALB/c mice were tube-fed with 25 mg ASEA/kg BW/day in 50 μl sunflower oil, while the control and PDTC (pyrrolidine dithiocarbamate, an anti-inflammatory agent groups were tube-fed with 50 μl sunflower oil/day only. After one week of tube-feeding, the PDTC group was injected with 50 mg/kg BW PDTC and one hour later, all of the mice were injected with 15 mg/kg BW LPS. The results showed that the ASEA and PDTC groups had significantly lower serum TNF-α, IL-6, and IL-1β levels at 9 hr after LPS challenge, and significantly higher survival rates than the control group. This study suggests that ASEA supplementation can suppress the production of pro-inflammatory cytokines and alleviate acute inflammatory hazards.

  7. Stress-related phenomena and detoxification mechanisms induced by common pharmaceuticals in alfalfa (Medicago sativa L.) plants

    Energy Technology Data Exchange (ETDEWEB)

    Christou, Anastasis [Agricultural Research Institute, P.O. Box 22016, 1516 Nicosia (Cyprus); Antoniou, Chrystalla; Christodoulou, Charalampia [Department of Agricultural Sciences, Biotechnology and Food Science, Cyprus University of Technology, 3603 Lemesos (Cyprus); Hapeshi, Evroula; Stavrou, Ioannis; Michael, Costas [NIREAS-International Water Research Center, University of Cyprus, P.O. Box 20537, 1678 Nicosia (Cyprus); Fatta-Kassinos, Despo [Department of Civil and Environmental Engineering, University of Cyprus, P.O. Box 20537, 1678 Nicosia (Cyprus); NIREAS-International Water Research Center, University of Cyprus, P.O. Box 20537, 1678 Nicosia (Cyprus); Fotopoulos, Vasileios, E-mail: vassilis.fotopoulos@cut.ac.cy [Department of Agricultural Sciences, Biotechnology and Food Science, Cyprus University of Technology, 3603 Lemesos (Cyprus)

    2016-07-01

    Pharmaceutically active compounds (PhACs) have been recently shown to exert phytotoxic effects. The present study explores the uptake, systemic translocation, and abiotic stress responses and detoxification mechanisms induced by the exposure of alfalfa plants grown in sand under greenhouse conditions to four common, individually applied PhACs (10 μg L{sup −1}) (diclofenac, sulfamethoxazole, trimethoprim, 17a-ethinylestradiol) and their mixture. Stress physiology markers (lipid peroxidation, proline, H{sub 2}O{sub 2} and NO content, antioxidant activity assays) and gene expression levels of key plant detoxification components (including glutathione S-transferases, GST7, GST17; superoxide dismutases, CuZnSOD, FeSOD; proton pump, H{sup +}-ATP, and cytochrome c oxidase, CytcOx), were evaluated. PhACs were detected in significantly higher concentrations in roots compared with leaves. Stress related effects, manifested via membrane lipid peroxidation and oxidative burst, were local (roots) rather than systemic (leaves), and exacerbated when the tested PhACs were applied in mixture. Systemic accumulation of H{sub 2}O{sub 2} in leaves suggests its involvement in signal transduction and detoxification responses. Increased antioxidant enzymatic activities, as well as upregulated transcript levels of GST7, GST17, H{sup +}-ATPase and CytcOx, propose their role in the detoxification of the selected PhACs in plants. The current findings provide novel biochemical and molecular evidence highlighting the studied PhACs as an emerging abiotic stress factor, and point the need for further research on wastewater flows under natural agricultural environments. - Highlights: • PhACs were detected in higher concentrations in roots compared with leaves. • Stress effects were local and exacerbated when PhACs were applied in mixture. • H{sub 2}O{sub 2} may be involved in signal transduction and detoxification responses. • GSTs, H{sup +}-ATPase and CytcOx contribute to the

  8. Regulating Alfalfa (Medicago Sativa L.) Vegetative and Reproductive Growth%紫花苜蓿营养生长与生殖生长调控

    Institute of Scientific and Technical Information of China (English)

    杜文华; 曹致中

    2005-01-01

    主要研究了播种行距,灌水量,N、P、K肥施用量,植物生长延缓剂,微肥,干燥剂对甘农3号紫花苜蓿(Medicago sativa L.CV.Gannong No·3)(下简称苜蓿)营养生长和生殖生长的影响,及其种群的生长冗余。结果表明。

  9. Advances in Study on Bio-Energy Utilization of Stem Cell Wall Components in Alfalfa (Medicago sativa L.)%紫花苜蓿(Medicago sativa L.)生物能源利用的研究进展

    Institute of Scientific and Technical Information of China (English)

    王晓娟; 张树振; 林双双; 邓志刚; 金樑

    2013-01-01

    紫花苜蓿(Medicago sativa L.)适应性强、生物质产量高,茎可用于生产酒精,叶片可用于家畜饲料,是最具开发潜力的能源植物之一.本文从紫花苜蓿生物能源利用角度出发,系统回顾了近年来紫花苜蓿作为能源植物在种质资源评价、细胞壁主要成分(纤维素、半纤维素、木质素)合成途径及其遗传调控以及栽培管理对酒精生产效率的影响等方面的研究进展,重点讨论了苜蓿细胞壁发育和木质素生物合成基因及其调控效应,并 对紫花苜蓿作为能源植物的研发前景进行了展望.

  10. Effects of untreated and treated wastewater at the morphological, physiological and biochemical levels on seed germination and development of sorghum (Sorghum bicolor (L.) Moench), alfalfa (Medicago sativa L.) and fescue (Festuca arundinacea Schreb.).

    Science.gov (United States)

    Rekik, Imen; Chaabane, Zayneb; Missaoui, Amara; Bouket, Ali Chenari; Luptakova, Lenka; Elleuch, Amine; Belbahri, Lassaad

    2017-03-15

    Wastewater reuse in agriculture may help mitigate water scarcity. This may be reached if high quality treatments removing harmful pollutants are applied. The aim of the present study was to compare the effect of untreated (UTW) and treated wastewater (TW) on germination and seedlings development of alfalfa (Medicago sativa L.), fescue (Festuca arundinacea Schreb.) and sorghum (Sorghum bicolor (L.) Moench). UTW presented high turbidity (130 NTU), chemical and biological oxygen demand (COD, 719mgL(-1), BOD5, 291mgL(-1)) and metal concentrations. These levels caused mortality (18% for fescue), decreased germination speed in seeds (37.5% for alfalfa) and reductions of root and stem length in seedlings (80% and 22% respectively for alfalfa). Adverse effects on seeds germination were reflected at the biochemical level by increased H2O2 levels (6 times for sorghum after 5days) and by increased Malondialdehyde (MDA) levels (more than 600 times for sorghum roots) during seedlings development. When TW was used, these parameters were close to control seeds ones. They were also dependent on plant species and developmental stage. Therefore, for efficient reclaimed wastewater reuse in irrigation, suitable crops, displaying wide tolerance to toxic contents during germination and later seedling development stages have to be selected.

  11. Fotossíntese em alfafa (Medicago sativa L. sob supressão e ressuprimento de fosfato Photosynthesis in alfalfa (Medicago sativa L. under phosphate suppression and ressuply

    Directory of Open Access Journals (Sweden)

    Fernando Teixeira Gomes

    2003-10-01

    Full Text Available Neste estudo, foram avaliados os efeitos da supressão e do ressuprimento de fosfato (Pi sobre a fotossíntese e eficiência fotoquímica de plantas de Medicago sativa cv. Flórida 77, em diferentes estádios do desenvolvimento vegetativo (V3, V4 e reprodutivo (R6, R8. O ensaio foi conduzido em casa de vegetação e as plantas cultivadas na solução nutritiva de HOAGLAND & ARNON (1950, contendo 0,14mmol L-1 de Pi. A supressão de Pi por dez dias reduziu os teores de fósforo nas folhas amostradas, em todos os estádios do desenvolvimento. Entretanto, com o ressuprimento, somente nos estádios vegetativos, os valores foram semelhantes ao tratamento controle. A fotossíntese por área foliar, em todos os estádios do desenvolvimento diminuiu com a supressão de Pi. De modo geral, o ressuprimento de Pi à solução nutritiva resultou em recuperação na fotossíntese, excetuando-se as plantas no estádio V3, uma indicação de que o período de supressão não causou danos permanentes no aparato fotossintético. Os teores dos pigmentos fotossintéticos e a eficiência fotoquímica do fotossistema II (FS II, avaliada pela relação Fv/Fm, não foram alterados quando as plantas foram submetidas à supressão de Pi. Esse resultado demonstra que o transporte de elétrons através do FS II não limitou a fotossíntese nas folhas amostradas, sob supressão de Pi, sugerindo que a supressão causou efeito mais pronunciado na etapa bioquímica da fotossíntese.This work evaluated the phosphate (Pi suppression and ressupply on photosynthesis and photochemical efficiency from Medicago sativa plants cv. Florida 77, in different growth stages (V3 and V4 and reproductive (R6 and R8. The experiment was performed in a greenhouse, the plants being cultivated in HOAGLAND & ARMOND (1950 nutritive solution containing 0,14mmol L-1 of Pi. Pi suppression for ten days reduced Pi levels in sampled leaves, in all growth stages. However, with the re-supply only in the

  12. Comparison of the phytoremediation potentials of Medicago falcata L. And Medicago sativa L. in aged oil-sludge-contaminated soil.

    Science.gov (United States)

    Panchenko, Leonid; Muratova, Anna; Turkovskaya, Olga

    2017-01-01

    Thirteen-year monitoring of the vegetation growing in the industrial and adjacent areas of an oil refinery showed the prevalence of yellow medick (Medicago falcata L.) over other plant species, including alfalfa (Medicago sativa L.). A comparative field study of the two Medicago species established that yellow medick and alfalfa exhibited similar resistance to soil petroleum hydrocarbons and that the pollutant concentration in their rhizosphere was 30% lower than that in the surrounding bulk soil. In laboratory pot experiments, yellow medick reduced the contaminant content by 18% owing to the degradation of the major heavy oil fractions, such as paraffins, naphthenes, and alcohol and benzene tars; and it was more successful than alfalfa. Both species were equally effective in stimulating the total number of soil microorganisms, but the number of hydrocarbon-oxidizing microorganisms, including polycyclic aromatic hydrocarbon degraders, was larger in the root zone of alfalfa. In turn, yellow medick provided a favorable balance of available nitrogen. Both Medicago species equally stimulated the dehydrogenase and peroxidase activities of the soil, and yellow medick increased the activity of soil polyphenol oxidase but reduced the activity of catalase. The root tissue activity of catalase, ascorbate oxidase, and tyrosinase was grater in alfalfa than in yellow medick. The peroxidase activity of plant roots was similar in both species, but nondenaturing polyacrylamide gel electrophoresis showed some differences in the peroxidase profiles of the root extracts of alfalfa and yellow medick. Overall, this study suggests that the phytoremediation potentials of yellow medick and alfalfa are similar, with some differences.

  13. Plant regeneration from proroplasts of alfalfa (Medicago sativa) via somatic embryogenesis Regeneração de plantas a partir de protoplastos de alfafa (Medicago sativa) via embriogênese somática

    OpenAIRE

    Mariza Monteiro; Beatriz Appezzato-da-Glória; Maria José Valarini; Carlos Alberto de Oliveira; Maria Lucia Carneiro Vieira

    2003-01-01

    Alfalfa is one of the most frequently studied species from the production of tissue culture-derived embryos point of view. In this study, five alfalfa cultivars were analyzed with reference to their ability to regenerate plants from protoplast cultures via somatic embryogenesis. Plant regeneration from leaf-derived protoplasts isolated from the cultivar Rangelander was achieved using a protocol defined for alfalfa cell suspension-derived embryogenesis. Because of its high efficiency, this pro...

  14. Nodule-enhanced expression of a sucrose phosphate synthase gene member (MsSPSA) has a role in carbon and nitrogen metabolism in the nodules of alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Aleman, Lorenzo; Ortega, Jose Luis; Martinez-Grimes, Martha; Seger, Mark; Holguin, Francisco Omar; Uribe, Diana J; Garcia-Ibilcieta, David; Sengupta-Gopalan, Champa

    2010-01-01

    Sucrose phosphate synthase (SPS) catalyzes the first step in the synthesis of sucrose in photosynthetic tissues. We characterized the expression of three different isoforms of SPS belonging to two different SPS gene families in alfalfa (Medicago sativa L.), a previously identified SPS (MsSPSA) and two novel isoforms belonging to class B (MsSPSB and MsSPSB3). While MsSPSA showed nodule-enhanced expression, both MsSPSB genes exhibited leaf-enhanced expression. Alfalfa leaf and nodule SPS enzymes showed differences in chromatographic and electrophoretic migration and differences in V (max) and allosteric regulation. The root nodules in legume plants are a strong sink for photosynthates with its need for ATP, reducing power and carbon skeletons for dinitrogen fixation and ammonia assimilation. The expression of genes encoding SPS and other key enzymes in sucrose metabolism, sucrose phosphate phosphatase and sucrose synthase, was analyzed in the leaves and nodules of plants inoculated with Sinorhizobium meliloti. Based on the expression pattern of these genes, the properties of the SPS isoforms and the concentration of starch and soluble sugars in nodules induced by a wild type and a nitrogen fixation deficient strain, we propose that SPS has an important role in the control of carbon flux into different metabolic pathways in the symbiotic nodules.

  15. Molecular cloning, characterization, and expression of an alfalfa (Medicago sativa L.) heme oxygenase-1 gene, MsHO1, which is pro-oxidants-regulated.

    Science.gov (United States)

    Fu, Guang-Qing; Xu, Sheng; Xie, Yan-Jie; Han, Bin; Nie, Li; Shen, Wen-Biao; Wang, Ren

    2011-07-01

    It has been documented that plant heme oxygenase-1 (HO-1; EC 1.14.99.3) is both development- and stress-regulated, thus it plays a vital role in light signalling and stress responses. In this study, an alfalfa (Medica sativa L.) HO-1 gene MsHO1 was isolated and sequenced. It contains four exons and three introns within genomic DNA sequence and encodes a polypeptide with 283 amino acids. MsHO1 had a conserved HO signature sequence and showed high similarity to other HOs in plants, especially HO-1 isoform. The MsHO1:GFP fusion protein was localized in the chloroplast. Further biochemical activity analysis of mature MsHO1, which was expressed in Escherichia coli, showed that the Vmax was 48.78 nmol biliverdin-IXα (BV) h⁻¹ nmol⁻¹ protein with an apparent Km value for hemin of 2.33 μM, and the optimum Tm and pH were 37 °C and 7.2, respectively. Results of semi-quantitative RT-PCR and western blot showed that the expressions of MsHO1 were higher in alfalfa stems and leaves than those in germinating seeds and roots. Importantly, MsHO1 gene expression and protein level were induced significantly by some pro-oxidant compounds, including hemin and nitric oxide (NO) donor sodium nitroprusside (SNP). In conclusion, MsHO1 may play an important role in oxidative responses.

  16. Integration and Expression of gfp in the plastid of Medicago sativa L.

    Science.gov (United States)

    Xing, Shaochen; Wei, Zhengyi; Wang, Yunpeng; Liu, Yanzhi; Lin, Chunjing

    2014-01-01

    Here we describe a protocol of alfalfa (Medicago sativa L.) plastid transformation by which gfp, a gene encoding the green fluorescent protein (GFP), is inserted into plastid genome via particle bombardment and homoplastomic plant is obtained. Plastid engineering is likely to make a significant contribution to the genetic improvement of this crop and the production of vaccines and therapeutic proteins.

  17. Plant regeneration from proroplasts of alfalfa (Medicago sativa via somatic embryogenesis Regeneração de plantas a partir de protoplastos de alfafa (Medicago sativa via embriogênese somática

    Directory of Open Access Journals (Sweden)

    Mariza Monteiro

    2003-12-01

    Full Text Available Alfalfa is one of the most frequently studied species from the production of tissue culture-derived embryos point of view. In this study, five alfalfa cultivars were analyzed with reference to their ability to regenerate plants from protoplast cultures via somatic embryogenesis. Plant regeneration from leaf-derived protoplasts isolated from the cultivar Rangelander was achieved using a protocol defined for alfalfa cell suspension-derived embryogenesis. Because of its high efficiency, this procedure is recommended for protoplast electroporation-mediated genetic transformation of alfalfa.A alfafa é uma das espécies mais freqüentemente estudadas do ponto de vista da produção de embriões somáticos derivados da cultura de tecidos. Neste trabalho, cinco cultivares de alfafa foram analisados com referência à capacidade de regenerar plantas a partir de culturas de protoplastos via embriogênese somática. Regeneração de plantas a partir de protoplastos isolados de folhas da cultivar Rangelander foi obtida usando-se um protocolo definido para embriogênese somática derivada de suspensões celulares de alfafa. Em função da sua alta eficiência, recomenda-se o uso deste procedimento para transformação genética de alfafa mediada por eletroporação de protoplastos.

  18. Bioaccumulation and degradation of pentachloronitrobenzene in Medicago sativa.

    Science.gov (United States)

    Li, Ying Ying; Yang, Hong

    2013-04-15

    Pentachloronitrobenzene (PCNB) is a fungicide belonging to the organochlorine family and used extensively in agriculture for crop production. Many studies have implied that PCNB has become an environmental concern due to its widespread contamination in eco-systems. However, whether PCNB is bioaccumulated, degraded and phytotoxic in plants is poorly understood. In this study, several alfalfa (Medicago sativa) cultivars were grown in soil with PCNB to investigate their absorption and catabolism, including PCNB residues in the soil and PCNB-induced toxic responses in plants. Alfalfa plants varied widely in their ability to accumulate and degrade PCNB. The degradation rate of PCNB was 66.26-77.68% after alfalfa growth in the soils for 20 d, while the rates in the control (soil without alfalfa) were only 48.42%. Moreover, concentrations of PCNB residues in the rhizosphere soil were significantly higher than those in the non-rhizosphere soils. Alfalfa exposed to 10 mg kg(-1) PCNB showed inhibited growth and oxidative damage, but the effects of PCNB on the cultivars differed significantly, indicating that the alfalfa cultivars have different tolerance to PCNB. Activities of invertase (INV), urease (URE), polyphenol oxidase (PPO), alkaline phosphatase (ALP) and acid phosphatase (ACP) were assayed in the treated soils and showed that the enzyme activities were altered after PCNB exposure. The URE, PPO, ALP and ACP activities were increased in soil following the planting of alfalfa. The objective of the study was to analyze the potential of different cultivars of alfalfa to accumulate and degrade PCNB from the contaminated soil.

  19. Occurrence of alfalfa (Medicago sativa L.) populations along roadsides in southern Manitoba, Canada and their potential role in intraspecific gene flow.

    Science.gov (United States)

    Bagavathiannan, Muthukumar V; Gulden, Robert H; Van Acker, Rene C

    2011-04-01

    Alfalfa is a highly outcrossing perennial species that can be noticed in roadsides as feral populations. There remains little information available on the extent of feral alfalfa populations in western Canadian prairies and their role in gene flow. The main objectives of this study were (a) to document the occurrence of feral alfalfa populations, and (b) to estimate the levels of outcrossing facilitated by feral populations. A roadside survey confirmed widespread occurrence of feral alfalfa populations, particularly in alfalfa growing regions. The feral populations were dynamic and their frequency ranged from 0.2 to 1.7 populations km(-1). In many cases, the nearest feral alfalfa population from alfalfa production field was located within a distance sufficient for outcrossing in alfalfa. The gene flow study confirmed that genes can move back and forth between feral and cultivated alfalfa populations. In this study, the estimated outcrossing levels were 62% (seed fields to feral), 78% (feral to seed fields), 82% (hay fields to feral) and 85% (feral to feral). Overall, the results show that feral alfalfa plants are prevalent in alfalfa producing regions in western Canada and they can serve as bridges for gene flow at landscape level. Management of feral populations should be considered, if gene flow is a concern. Emphasis on preventing seed spill/escapes and intentional roadside planting of alfalfa cultivars will be particularly helpful. Further, realistic and pragmatic threshold levels should be established for markets sensitive to the presence of GE traits.

  20. 肇东苜蓿与三种国外引进苜蓿品种间杂交的初步研究%Preliminary Study on Intervarietal Hybridization of Medicago sativa L.cv.Zhaodong and Three Introduced Abroad Alfalfa

    Institute of Scientific and Technical Information of China (English)

    刘凤歧; 张月学; 唐凤兰; 陈晶; 韩微波; 刘杰淋; 尚晨

    2012-01-01

    Heilongjiang is a high-latitude alpine regions,so breeding high-yield,cold resistant and adaptable Medicago sativa L.varieties become the primary breeding goal.The reciprocal intervarietal hybridizations between local variety Medicago sativa L.cv.Zhaodong of cold hardiness and adaptability and three abroad varieties of alfalfa of high yield were undertaken using conventional hybridization methods.Three abroad varieties of alfalfa included WL323 introducing from the USA,Pleven6 introducing from Bulgarian and Beza87 introducing from Russian.Meantime,pollen activities were detected by the method of in vitro germination,and pod bearing rates were investigated and analyzed.The results showed that:there were significant differences in pod bearing rate among male and female parents,and extremely significant differences existed among cross combination.The highest pod bearing rate of reciprocal cross was between Medicago sativa L.cv.Zhangdong and WL323,which laid the foundation of parent selection in cross breeding of alfalfa and provided the basis material for breeding new varieties.%黑龙江属高纬高寒地区,培育高产、抗寒、适应性强的品种成为紫花苜蓿(Medicago sativa L.)育种的首要目标,采用常规杂交方法对抗寒性、适应性强的地方品种肇东苜蓿(Medicago sativa L.cv.Zhaodong)和国外引进的3种高产苜蓿:美国苜蓿WL323、保加利亚苜蓿Pleven6、俄罗斯苜蓿Beza87分别进行正反品种间杂交,利用离体萌发法对杂交亲本的花粉活性进行检测,以及杂交结荚率等数据进行统计分析。结果表明:父、母本对结荚率影响显著,不同杂交组合结荚率差异极显著,肇东苜蓿与WL323正反交的结荚率高于其它杂交组合,为苜蓿杂交育种亲本选配奠定基础,同时为苜蓿杂交新品种的选育提供了基础材料。

  1. Identification of loci associated with drought resistance traits in heterozygous autotetraploid alfalfa (Medicago sativa L.) using genome-wide association studies with genotyping by sequencing

    Science.gov (United States)

    Developing molecular markers associated with drought resistance would be helpful for improving the accuracy in selecting resistant alfalfa, and accelerating the breeding process. A panel of accessions comprised of 200 alfalfa cultivars and landraces with potential drought tolerance were selected fro...

  2. Phytotoxicity of three plant-based biodiesels, unmodified castor oil, and Diesel fuel to alfalfa (Medicago sativa L.), lettuce (Lactuca sativa L.), radish (Raphanus sativus), and wheatgrass (Triticum aestivum).

    Science.gov (United States)

    Bamgbose, Ifeoluwa; Anderson, Todd A

    2015-12-01

    The wide use of plant-based oils and their derivatives, in particular biodiesel, have increased extensively over the past decade to help alleviate demand for petroleum products and improve the greenhouse gas emissions profile of the transportation sector. Biodiesel is regarded as a clean burning alternative fuel produced from livestock feeds and various vegetable oils. Although in theory these animal and/or plant derived fuels should have less environmental impact in soil based on their simplified composition relative to Diesel, they pose an environmental risk like Diesel at high concentrations when disposed. The aim of the present study was to ascertain the phytotoxicity of three different plant-derived biodiesels relative to conventional Diesel. For phytotoxicological analysis, we used seeds of four crop plants, Medicago sativa, Lactuca sativa, Raphanus sativus, and Triticum aestivum to analyze the germination of seeds in contaminated soil samples. The toxicological experiment was conducted with two different soil textures: sandy loam soil and silt loam soil. The studied plant-based biodiesels were safflower methyl-ester, castor methyl ester, and castor ethyl-ester. Biodiesel toxicity was more evident at high concentrations, affecting the germination and survival of small-seeded plants to a greater extent. Tolerance of plants to the biodiesels varied between plant species and soil textures. With the exception of R. sativus, all plant species were affected and exhibited some sensitivity to the fuels, such as delayed seedling emergence and slow germination (average=10 days) at high soil concentrations (0.85% for Diesel and 1.76% for the biodiesels). Tolerance of plants to soil contamination had a species-specific nature, and on average, decreased in the following order: Raphanus sativus (0-20%)>Triticum aestivum (10-40%) ≥ Medicago sativa> Lactuca sativa (80-100%). Thus, we conclude that there is some phytotoxicity associated with plant-based biodiesels. Further

  3. Alfalfa (Medicago sativa L./maize (Zea mays L. intercropping provides a feasible way to improve yield and economic incomes in farming and pastoral areas of northeast China.

    Directory of Open Access Journals (Sweden)

    Baoru Sun

    Full Text Available Given the growing challenges to food and eco-environmental security as well as sustainable development of animal husbandry in the farming and pastoral areas of northeast China, it is crucial to identify advantageous intercropping modes and some constraints limiting its popularization. In order to assess the performance of various intercropping modes of maize and alfalfa, a field experiment was conducted in a completely randomized block design with five treatments: maize monoculture in even rows, maize monoculture in alternating wide and narrow rows, alfalfa monoculture, maize intercropped with one row of alfalfa in wide rows and maize intercropped with two rows of alfalfa in wide rows. Results demonstrate that maize monoculture in alternating wide and narrow rows performed best for light transmission, grain yield and output value, compared to in even rows. When intercropped, maize intercropped with one row of alfalfa in wide rows was identified as the optimal strategy and the largely complementary ecological niches of alfalfa and maize were shown to account for the intercropping advantages, optimizing resource utilization and improving yield and economic incomes. These findings suggest that alfalfa/maize intercropping has obvious advantages over monoculture and is applicable to the farming and pastoral areas of northeast China.

  4. Alfalfa (Medicago sativa L.)/maize (Zea mays L.) intercropping provides a feasible way to improve yield and economic incomes in farming and pastoral areas of northeast China.

    Science.gov (United States)

    Sun, Baoru; Peng, Yi; Yang, Hongyu; Li, Zhijian; Gao, Yingzhi; Wang, Chao; Yan, Yuli; Liu, Yanmei

    2014-01-01

    Given the growing challenges to food and eco-environmental security as well as sustainable development of animal husbandry in the farming and pastoral areas of northeast China, it is crucial to identify advantageous intercropping modes and some constraints limiting its popularization. In order to assess the performance of various intercropping modes of maize and alfalfa, a field experiment was conducted in a completely randomized block design with five treatments: maize monoculture in even rows, maize monoculture in alternating wide and narrow rows, alfalfa monoculture, maize intercropped with one row of alfalfa in wide rows and maize intercropped with two rows of alfalfa in wide rows. Results demonstrate that maize monoculture in alternating wide and narrow rows performed best for light transmission, grain yield and output value, compared to in even rows. When intercropped, maize intercropped with one row of alfalfa in wide rows was identified as the optimal strategy and the largely complementary ecological niches of alfalfa and maize were shown to account for the intercropping advantages, optimizing resource utilization and improving yield and economic incomes. These findings suggest that alfalfa/maize intercropping has obvious advantages over monoculture and is applicable to the farming and pastoral areas of northeast China.

  5. Identification of Loci Associated with Drought Resistance Traits in Heterozygous Autotetraploid Alfalfa (Medicago sativa L. Using Genome-Wide Association Studies with Genotyping by Sequencing.

    Directory of Open Access Journals (Sweden)

    Tiejun Zhang

    Full Text Available Drought resistance is an important breeding target for enhancing alfalfa productivity in arid and semi-arid regions. Identification of genes involved in drought tolerance will facilitate breeding for improving drought resistance and water use efficiency in alfalfa. Our objective was to use a diversity panel of alfalfa accessions comprised of 198 cultivars and landraces to identify genes involved in drought tolerance. The panel was selected from the USDA-ARS National Plant Germplasm System alfalfa collection and genotyped using genotyping by sequencing. A greenhouse procedure was used for phenotyping two important traits associated with drought tolerance: drought resistance index (DRI and relative leaf water content (RWC. Marker-trait association identified nineteen and fifteen loci associated with DRI and RWC, respectively. Alignments of target sequences flanking to the resistance loci against the reference genome of M. truncatula revealed multiple chromosomal locations. Markers associated with DRI are located on all chromosomes while markers associated with RWC are located on chromosomes 1, 2, 3, 4, 5, 6 and 7. Co-localizations of significant markers between DRI and RWC were found on chromosomes 3, 5 and 7. Most loci associated with DRI in this work overlap with the reported QTLs associated with biomass under drought in alfalfa. Additional significant markers were targeted to several contigs with unknown chromosomal locations. BLAST search using their flanking sequences revealed homology to several annotated genes with functions in stress tolerance. With further validation, these markers may be used for marker-assisted breeding new alfalfa varieties with drought resistance and enhanced water use efficiency.

  6. Identification of Loci Associated with Drought Resistance Traits in Heterozygous Autotetraploid Alfalfa (Medicago sativa L.) Using Genome-Wide Association Studies with Genotyping by Sequencing.

    Science.gov (United States)

    Zhang, Tiejun; Yu, Long-Xi; Zheng, Ping; Li, Yajun; Rivera, Martha; Main, Dorrie; Greene, Stephanie L

    2015-01-01

    Drought resistance is an important breeding target for enhancing alfalfa productivity in arid and semi-arid regions. Identification of genes involved in drought tolerance will facilitate breeding for improving drought resistance and water use efficiency in alfalfa. Our objective was to use a diversity panel of alfalfa accessions comprised of 198 cultivars and landraces to identify genes involved in drought tolerance. The panel was selected from the USDA-ARS National Plant Germplasm System alfalfa collection and genotyped using genotyping by sequencing. A greenhouse procedure was used for phenotyping two important traits associated with drought tolerance: drought resistance index (DRI) and relative leaf water content (RWC). Marker-trait association identified nineteen and fifteen loci associated with DRI and RWC, respectively. Alignments of target sequences flanking to the resistance loci against the reference genome of M. truncatula revealed multiple chromosomal locations. Markers associated with DRI are located on all chromosomes while markers associated with RWC are located on chromosomes 1, 2, 3, 4, 5, 6 and 7. Co-localizations of significant markers between DRI and RWC were found on chromosomes 3, 5 and 7. Most loci associated with DRI in this work overlap with the reported QTLs associated with biomass under drought in alfalfa. Additional significant markers were targeted to several contigs with unknown chromosomal locations. BLAST search using their flanking sequences revealed homology to several annotated genes with functions in stress tolerance. With further validation, these markers may be used for marker-assisted breeding new alfalfa varieties with drought resistance and enhanced water use efficiency.

  7. Effects of AN Alfalfa (medicago Sativa) Buffer Strip on Leached δ15NNITRATE Values: Implications for Management of Hydrologic N Losses

    Science.gov (United States)

    Kelley, C. J.; Keller, C. K.; Smith, J. L.; Evans, R. D.; Harlow, B.

    2011-12-01

    Buffer strips are commonly used to decrease agricultural runoff with the objective of limiting sediment and agrochemicals fluxes to surface waters. The objective of this study was to determine the effects of an alfalfa buffer strip on the magnitude and source(s) of leached nitrate from a dryland agricultural field. Previous research at the Cook Agronomy Farm has inferred two sources of nitrate in tile drain discharge, a high-discharge-season (January through May) synthetic fertilizer source, and a low-discharge-season (June through December) soil organic nitrogen source. This study examines how a change in management strategy and crop species alters the low discharge season nitrate source. In the spring of 2006 an alfalfa buffer strip approximately 20 m wide was planted running approximately north-south in the lowland portion of a 12 ha tile-drained field bordering a ditch that drains into Missouri Flat Creek. Three-year (2003 through 2005) average NO3--N flux prior to the planting of the alfalfa buffer strip was ~0.40 kg ha-1 year-1. After planting, the three-year (2006 through 2008) average NO3--N flux was ~0.38 kg ha-1 year-1. The lack of evident buffer-strip influence on the fluxes may be due in part to the large variation in precipitation amounts and timing that control water flows through the system. Three-year average δ15Nnitrate values for the tile drain pre and post planting of the alfalfa buffer strip were 6.9 ± 1.1 % and 4.2 ± 0.9 % respectively. We hypothesize that the significant difference indicates that the alfalfa strip affects the source of leached nitrate. Before planting the alfalfa buffer strip, the interpreted source of nitrate was mineralization of soil organic nitrogen from non-N2 fixing crops (spring and summer wheat varieties). After planting the alfalfa buffer strip, the source of nitrate was interpreted to be a mixture of mineralized soil organic nitrogen from N2 fixing alfalfa and non-N2 fixing crops. Further work is needed to test

  8. Aluminium-induced reduction of plant growth in alfalfa (Medicago sativa) is mediated by interrupting auxin transport and accumulation in roots

    OpenAIRE

    Shengyin Wang; Xiaoyan Ren; Bingru Huang; Ge Wang; Peng Zhou; Yuan An

    2016-01-01

    The objective of this study was to investigate Al3+-induced IAA transport, distribution, and the relation of these two processes to Al3+-inhibition of root growth in alfalfa. Alfalfa seedlings with or without apical buds were exposed to 0 or 100 μM AlCl3 and were foliar sprayed with water or 6 mg L−1 IAA. Aluminium stress resulted in disordered arrangement of cells, deformed cell shapes, altered cell structure, and a shorter length of the meristematic zone in root tips. Aluminium stress signi...

  9. Survival and growth of Alfalfa (Medicago sativa l.) inoculated with an am fungus (Glomus intraradices) in contaminated soils treated with two different remediation technologies (bio-pile and thermal desorption)

    Energy Technology Data Exchange (ETDEWEB)

    Norini, M.P.; Beguiristain, Th.; Leyval, C. [LIMOS UMR 7137 CNRS-UHP Nancy - Faculty of Sciences, 54 - Vandoeuvre-les-Nancy (France)

    2005-07-01

    (Medicago sativa L.), inoculated or not with an AM fungus (Glomus intraradices) and fertilized with Hewitt solution. Control non-inoculated and non-fertilized plants were included. There was four replicates per treatment. After 2 months, plant survival and growth was measured, as well as mycorrhizal colonization of roots. PAH in rhizosphere soils was analyzed using ASE and GC-FID. Major and trace elements in plants were analyzed after acid digestion using ICP. AM fungal and bacterial communities present in roots and rhizosphere were also analysed after DNA extraction with a PCR-TGGE technique. Plant survival rate was significantly lower in the soil treated with bio-pile than in untreated soil. Non-inoculated and non fertilized alfalfa biomass was lower with soil treated with bio-pile and thermal desorption than with untreated soil. Mycorrhizal inoculation as well as fertilization significantly improved alfalfa growth in the soil treated with bio-pile. In the soil treated with thermal desorption, shoot and root biomass were significantly higher with mycorrhizal inoculation and fertilization. Estimation of root colonization showed that the roots of un-inoculated plants growing on the untreated contaminated soil contained indigenous mycorrhizal fungi. With the soil treated with bio-pile, mycorrhizal colonization of un-inoculated plants was significantly lower, while no colonization was observed in the roots in the soil treated with thermal desorption. Inoculation with a mycorrhizal fungus increased root colonization rate in both treated soils. It also significantly increased the number of rhizobia nodules. Phosphorus concentration in plant roots and shoots was significantly improved by mycorrhizal inoculation in soil treated with thermal desorption. Data on PAH concentration in soils and fungal and bacterial communities will be also presented and discussed.

  10. Agrophysiological and biochemical properties associated with adaptation of Medicago sativa populations to water deficit

    OpenAIRE

    Farissi, Mohamed; BOUIZGAREN, Abdelaziz; FAGHIRE, Mustapha; Bargaz, Adnane; Ghoulam, Cherki

    2013-01-01

    The effect of water deficit on growth and some physiological and biochemical parameters related to water deficit tolerance was studied in 4 Moroccan alfalfa Medicago sativa L. populations that originated from the mountains and oases of Morocco. The experiment was conducted in greenhouse conditions. Seeds were allowed to germinate in pots filled with sand and peat at a 2:1 ratio, respectively. After 1 month of sowing, the plants were subjected to 3 water regimes: optimal irrigation (75% of fie...

  11. Genotyping-by-sequencing based genome-wide association studies on Verticillium wilt resistance in heterozygous autotetraploid alfalfa (Medicago sativa L.)

    Science.gov (United States)

    Verticillium wilt (VW) is a fungal disease which causes severe yield loss in alfalfa. The most effective method to control the disease is through the development and use of resistant varieties. Identification of gene loci linked to VW resistance will facilitate breeding for the disease-resistant al...

  12. Detection of the genetic variation of polygalacturonase-inhibiting protein gene 2 in autotetraploid alfalfa (Medicago sativa) using an improved SSCP technique.

    Science.gov (United States)

    Gui, Z; Liu, H Q; Wang, Y; Yuan, Q H; Xin, N; Zhang, X; Li, X L; Pi, Y S; Gao, J M

    2014-12-04

    In this study, 2 approaches were adopted to obtain good single-strand conformation polymorphism (SSCP) data for autotetraploid alfalfa; primers were added to PCR products, and fluorescent-labeled primers were utilized. PCR-SSCP conditions for a 331-bp fragment in the coding region of polygalacturonase-inhibiting protein gene 2 in alfalfa (MsPGIP2) were optimized, and the results showed that the best SSCP gel pattern could be obtained when the loading mixture was made by mixing 1 μL PCR products, 0.2 to 0.8 μL unlabeled primers (50 μM) and 4 to 16 μL loading buffer. Furthermore, the use of the fluorescent-labeled primers resulted in 2 separated electrophoresis images from 2 complementary single DNA strands, thus making the determination of alleles and idiotypes a relatively easy task. In addition, the results of sequencing prove that the determination of alleles and idiotypes were accurate based on SSCP analysis. Finally, a total of 9 alleles with 18 SNP sites were identified for MsPGIP2 in the alfalfa variety 'Algonquin'. In conclusion, MsPGIP2 possessed great genetic variation, and the addition of primers to the PCR products in combination with the fluorescent labeling of primers could significantly improve the sensitivity and resolution of SSCP analysis. This technique could be used for genetic diversity detection and marker-assisted breeding of useful genes in autopolyploid species such as alfalfa.

  13. Ensifer, Phyllobacterium and Rhizobium species occupy nodules of Medicago sativa (alfalfa) and Melilotus alba (sweet clover) grown at a Canadian site without a history of cultivation

    Science.gov (United States)

    Phage resistant and susceptible bacteria from nodules of alfalfa and sweet clover grown at a site without a known history of cultivation, were identified as Ensifer, Rhizobium and Phyllobacterium species based on sequence analysis of ribosomal (16S and 23S rRNA)and protein encoding (atpD and recA) g...

  14. The Impact of Genotyping-by-Sequencing Pipelines on SNP Discovery and Identification of Markers Associated with Verticillium Wilt Resistance in Autotetraploid Alfalfa (Medicago sativa L.)

    Science.gov (United States)

    Yu, Long-Xi; Zheng, Ping; Bhamidimarri, Suresh; Liu, Xiang-Ping; Main, Dorie

    2017-01-01

    Verticillium wilt (VW) of alfalfa is a soilborne disease causing severe yield loss in alfalfa. To identify molecular markers associated with VW resistance, we used an integrated framework of genome-wide association study (GWAS) with high-throughput genotyping by sequencing (GBS) to identify loci associated with VW resistance in an F1 full-sib alfalfa population. Phenotyping was performed using manual inoculation of the pathogen to cloned plants of each individual and disease severity was scored using a standard scale. Genotyping was done by GBS, followed by genotype calling using three bioinformatics pipelines including the TASSEL-GBS pipeline (TASSEL), the Universal Network Enabled Analysis Kit (UNEAK), and the haplotype-based FreeBayes pipeline (FreeBayes). The resulting numbers of SNPs, marker density, minor allele frequency (MAF) and heterozygosity were compared among the pipelines. The TASSEL pipeline generated more markers with the highest density and MAF, whereas the highest heterozygosity was obtained by the UNEAK pipeline. The FreeBayes pipeline generated tetraploid genotypes, with the least number of markers. SNP markers generated from each pipeline were used independently for marker-trait association. Markers significantly associated with VW resistance identified by each pipeline were compared. Similar marker loci were found on chromosomes 5, 6, and 7, whereas different loci on chromosome 1, 2, 3, and 4 were identified by different pipelines. Most significant markers were located on chromosome 6 and they were identified by all three pipelines. Of those identified, several loci were linked to known genes whose functions are involved in the plants’ resistance to pathogens. Further investigation on these loci and their linked genes would provide insight into understanding molecular mechanisms of VW resistance in alfalfa. Functional markers closely linked to the resistance loci would be useful for MAS to improve alfalfa cultivars with enhanced resistance

  15. Alfalfa stem tissues: Cell wall deposition, composition, and degradability

    NARCIS (Netherlands)

    Jung, H.G.; Engels, F.M.

    2002-01-01

    Declining cell wall degradability of alfalfa (Medicago sativa L.) stems with maturation limits the nutritional value of alfalfa for ruminants. This study characterized changes in cell wall concentration, composition, and degradability by rumen microbes resulting from alfalfa stem tissue proliferatio

  16. In situ phytoremediation of PAH-contaminated soil by intercropping alfalfa (Medicago sativa L.) with tall fescue (Festuca arundinacea Schreb.) and associated soil microbial activity

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Mingming; Fu, Dengqiang; Teng, Ying; Shen, Yuanyuan; Luo, Yongming; Li, Zhengao [Chinese Academy of Sciences, Nanjing (China). Key Laboratory of Soil Environment and Pollution Remediation; Christie, Peter [Agri-Food and Biosciences Institute, Belfast (United Kingdom). Agri-Environment Branch

    2011-09-15

    Purpose: A 7-month field experiment was conducted to investigate the polycyclic aromatic hydrocarbon (PAH) remediation potential of two plant species and changes in counts of soil PAH-degrading bacteria and microbial activity. Materials and methods: Alfalfa and tall fescue were grown in monoculture and intercropped for 7 months in contaminated field soil. Soil and plant samples were analyzed for PAHs. Plant biomass, densities of PAH-degradation soil bacteria, soil microbial biomass C and N, enzyme activities, and the physiological profile of the soil microbial community were determined. Results and discussion: Average removal percentage of total PAHs in intercropping (30.5%) was significantly higher than in monoculture (19.9%) or unplanted soil (-0.6%). About 7.5% of 3-ring, 12.3% of 4-ring, and 17.2% of 5(+6)-ring PAHs were removed from the soil by alfalfa, with corresponding values of 25.1%, 10.4%, and 30.1% for tall fescue. Intercropping significantly enhanced the remediation efficiency. About 18.9% of 3-ring, 30.9% of 4-ring, and 33.4% of 5(+6)-ring PAHs were removed by the intercropping system. Higher counts of soil culturable PAH-degrading bacteria and elevated microbial biomass and enzyme activities were found after intercropping. Soil from intercropping showed significantly higher (p < 0.05) average well-color development obtained by the BIOLOG Ecoplate assay and Shannon-Weaver index compared with monoculture. Conclusions: Cropping promoted the dissipation of soil PAHs. Tall fescue gave greater removal of soil PAHs than alfalfa, and intercropping was more effective than monoculture. Intercropping of alfalfa and tall fescue may be a promising in situ bioremediation strategy for PAH-contaminated soils. (orig.)

  17. Transformation with TT8 and HB12 RNAi Constructs in Model Forage (Medicago sativa, Alfalfa) Affects Carbohydrate Structure and Metabolic Characteristics in Ruminant Livestock Systems.

    Science.gov (United States)

    Li, Xinxin; Zhang, Yonggen; Hannoufa, Abdelali; Yu, Peiqiang

    2015-11-04

    Lignin, a phenylpropanoid polymer present in secondary cell walls, has a negative impact on feed digestibility. TT8 and HB12 genes were shown to have low expression levels in low-lignin tissues of alfalfa, but to date, there has been no study on the effect of down-regulation of these two genes in alfalfa on nutrient chemical profiles and availability in ruminant livestock systems. The objectives of this study were to investigate the effect of transformation of alfalfa with TT8 and HB12 RNAi constructs on carbohydrate (CHO) structure and CHO nutritive value in ruminant livestock systems. The results showed that transformation with TT8 and HB12 RNAi constructs reduced rumen, rapidly degraded CHO fractions (RDCA4, P = 0.06; RDCB1, P < 0.01) and totally degraded CHO fraction (TRDCHO, P = 0.08). Both HB12 and TT8 populations had significantly higher in vitro digestibility of neutral detergent fiber (NDF) at 30 h of incubation (ivNDF30) compared to the control (P < 0.01). The TT8 populations had highest ivDM30 and ivNDF240. Transformation of alfalfa with TT8 and HB12 RNAi constructs induced molecular structure changes. Different CHO functional groups had different sensitivities and different responses to the transformation. The CHO molecular structure changes induced by the transformation were associated with predicted CHO availability. Compared with HB12 RNAi, transformation with TT8 RNAi could improve forage quality by increasing the availability of both NDF and DM. Further study is needed on the relationship between the transformation-induced structure changes at a molecular level and nutrient utilization in ruminant livestock systems when lignification is much higher.

  18. Expression of an alfalfa (Medicago sativa L.) ethylene response factor gene MsERF8 in tobacco plants enhances resistance to salinity.

    Science.gov (United States)

    Chen, Tingting; Yang, Qingchuan; Gruber, Margaret; Kang, Junmei; Sun, Yan; Ding, Wang; Zhang, Tiejun; Zhang, Xinquan

    2012-05-01

    Ethylene response factors (ERF) play crucial roles in plant development and response to stresses. Here, a novel cDNA fragment (MsERF8) encoding an ERF protein with an AP2 domain was isolated and characterized from alfalfa. The MsERF8 cDNA has an open reading frame of 603 bp and encodes a nuclear protein of 201 amino acids. Q-RT-PCR analysis revealed that MsERF8 was strongly enriched in roots and leaves compared with stems, flower buds and flowers of mature alfalfa plants. Bioinformatic analysis of the MsERF8 promoter indicated a number of elements associated with stress-related responses, and MsERF8 transcripts in alfalfa seedlings were induced by NaCl, PEG6000, Al(2)(SO(4))(3) and five different hormones. Expression of MsERF8 in transgenic tobacco plants resulted in higher tolerance to salinity than with non-transgenic plants. This data shows that MsERF8 is a gene which prevents or alleviates salinity damage and has strong potential to impart salt tolerance to other crop plants.

  19. Interactive effects of molasses by homofermentative and heterofermentative inoculants on fermentation quality, nitrogen fractionation, nutritive value and aerobic stability of wilted alfalfa (Medicago sativa L) silage.

    Science.gov (United States)

    Hashemzadeh-Cigari, F; Khorvash, M; Ghorbani, G R; Ghasemi, E; Taghizadeh, A; Kargar, S; Yang, W Z

    2014-04-01

    The effect of adding molasses (0, UM or 50 g/kg on DM basis, M) and two types of inoculant including homofermentative (HO) and a combination of homofermentative and propionate-producing bacterial (HOPAB) inoculants on silage fermentation quality, nitrogen fractionation and aerobic stability of pre-bloom, wilted alfalfa (AS) was determined in laboratory silos. The HOPAB inoculant was more effective than HO in reducing the alfalfa silage pH but increased propionate content in the absence of M (p alfalfa crop with M and HOPAB improved aerobic stability by increasing the concentration of acetate and propionate of AS respectively. Adding M tended (p < 0.10) to increase short-chain fatty acids (SCFA) and cumulative gas production (CGP). HOPAB alone increased DM disappearance at 24 h post-incubation and effective degradability assuming outflow rate of 8%/h relative to untreated AS (p < 0.05). It was concluded that adding M had no pronounced effects on AS fermentation quality, but increased aerobic stability. HOPAB-inoculated AS with no addition of M improved fermentation quality and increased DM degradability compared with HO.

  20. Overexpression of EsMcsu1 from the halophytic plant Eutrema salsugineum promotes abscisic acid biosynthesis and increases drought resistance in alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Zhou, C; Ma, Z Y; Zhu, L; Guo, J S; Zhu, J; Wang, J F

    2015-12-17

    The stress phytohormone abscisic acid (ABA) plays pivotal roles in plants' adaptive responses to adverse environments. Molybdenum cofactor sulfurases influence aldehyde oxidase activity and ABA biosynthesis. In this study, we isolated a novel EsMcsu1 gene encoding a molybdenum cofactor sulfurase from Eutrema salsugineum. EsMcus1 transcriptional patterns varied between organs, and its expression was significantly upregulated by abiotic stress or ABA treatment. Alfalfa plants that overexpressed EsMcsu1 had a higher ABA content than wild-type (WT) plants under drought stress conditions. Furthermore, levels of reactive oxygen species (ROS), ion leakage, and malondialdehyde were lower in the transgenic plants than in the WT plants after drought treatment, suggesting that the transgenic plants experienced less ROS-mediated damage. However, the expression of several stress-responsive genes, antioxidant enzyme activity, and osmolyte (proline and total soluble sugar) levels in the transgenic plants were higher than those in the WT plants after drought treatment. Therefore, EsMcsu1 overexpression improved drought tolerance in alfalfa plants by activating a series of ABA-mediated stress responses.

  1. Aluminium-induced reduction of plant growth in alfalfa (Medicago sativa) is mediated by interrupting auxin transport and accumulation in roots.

    Science.gov (United States)

    Wang, Shengyin; Ren, Xiaoyan; Huang, Bingru; Wang, Ge; Zhou, Peng; An, Yuan

    2016-07-20

    The objective of this study was to investigate Al(3+)-induced IAA transport, distribution, and the relation of these two processes to Al(3+)-inhibition of root growth in alfalfa. Alfalfa seedlings with or without apical buds were exposed to 0 or 100 μM AlCl3 and were foliar sprayed with water or 6 mg L(-1) IAA. Aluminium stress resulted in disordered arrangement of cells, deformed cell shapes, altered cell structure, and a shorter length of the meristematic zone in root tips. Aluminium stress significantly decreased the IAA concentration in apical buds and root tips. The distribution of IAA fluorescence signals in root tips was disturbed, and the IAA transportation from shoot base to root tip was inhibited. The highest intensity of fluorescence signals was detected in the apical meristematic zone. Exogenous application of IAA markedly alleviated the Al(3+)-induced inhibition of root growth by increasing IAA accumulation and recovering the damaged cell structure in root tips. In addition, Al(3+) stress up-regulated expression of AUX1 and PIN2 genes. These results indicate that Al(3+)-induced reduction of root growth could be associated with the inhibitions of IAA synthesis in apical buds and IAA transportation in roots, as well as the imbalance of IAA distribution in root tips.

  2. 陇东紫花苜蓿的栽培与田间管理技术%Longdong alfalfa Medicago sativa cultivation and management

    Institute of Scientific and Technical Information of China (English)

    王鑫

    2004-01-01

    对陇东地区紫花苜蓿Medicago sativa播种地的选择与准备,科学的施肥措施和品种选择,最适播期与播种方式的确定,主要病虫害的防治与耕作措施、最佳刈割期的选择等进行了系统的总结,提出了规范的栽培与管理技术措施,对提高当地紫花苜蓿的产量和品质,充分利用土地,发展当地支柱产业及经济可持续发展具有重要的参考价值.

  3. Evaluating Agronomic Performance and Investigating Molecular Structure of Drought and Heat Tolerant Wild Alfalfa (Medicago sativa L.) Collection from the Southeastern Turkey.

    Science.gov (United States)

    Basbag, Mehmet; Aydin, Ali; Sakiroglu, Muhammet

    2017-02-01

    Drought is a major stress factor for agricultural production including alfalfa production. One way to counterbalance the yield losses is the introgression of drought tolerant germplasm into breeding programs. As an effort to exploit such germplasm, 16 individual plants were selected from the Southeastern Turkey from their natural habitat and clonally propagated in field trials with an ultimate goal to use the germplasm as parents for releasing a synthetic cultivar. Forage yield and forage quality traits were evaluated and molecular genetic diversity among genotypes were determined using inter simple sequence repeat markers. Genotypes showed a variation from growth habit to yield and quality traits indicating sufficient phenotypic variation for diverse breeding efforts (for grazing or harvesting) and long term selection schemes. A large amount of genetic variation was observed even with a limited number of marker and genotypes. However, no pattern of spatial genetic structure was observed for the scale of the study when genetic variation is linked to the geographic origin. We conclude that ex situ natural variation provides a wealth of germplasm that could be incorporated into breeding programs aiming to improve drought tolerance. We also suggest an extensive collection of seeds/plant tissue from unique plants with desirable traits rather than putting more efforts to create a spatial germplasm sampling efforts in narrow regions.

  4. INFLUENCE OF pH AND TEMPERATURE ON GERMINATION ENERGY, GERMINATION, ROOT AND SEEDLINGS HYPOCOTIL LENGTH OF VARIOUS ALFALFA CULTIVARS (Medicago sativa L.

    Directory of Open Access Journals (Sweden)

    Gordana Bukvić

    2008-07-01

    Full Text Available The traits of germination energy, seed germination, as well as root and hypocotyls length of domestic alfalfa cultivars (Slavonka, Stela, Vuka were investigated in a climate chamber. The experiment was set up at two pH levels of water solution (4.00 and 6.00 and temperature levels of 10°C and 20°C using rolled filter paper method. Significant difference between cultivars (p=0.01, p=0.05 was determined for germination energy, seed germination and hypocotyls length. Cultivar Slavonka had the highest average values for germination energy and seed germination, and the lowest for hypocotyls length. Cultivar Vuka had the lowest germination energy (but with the same germination as Stela and the longest hypocotyls. Seed germination as well as root and hypocotyl length significantly depended (p=0.01 on pH of water solution. The higher average values of all traits were found at pH 4.00, except for germination energy. Temperature also significantly affected on all investigated traits (p=0.01, whilst the higher values were attained at higher temperature. Interactions cultivar x pH and cultivar x temperature were significant (p=0.01 for all traits, while pH x temperature interaction was not significant only for seed germination.

  5. Genetically engineered alfalfa and feral alfalfa plants: What should growers know?

    Science.gov (United States)

    Alfalfa (Medicago sativa subsp. sativa L) is the world’s most important forage crop. The western United States is the most important production area for both alfalfa forage and alfalfa seed. Alfalfa was the first major perennial genetically-engineered (GE)crop and a GE trait for resistance to glypho...

  6. Starch Grain Distribution in Taproots of Defoliated Medicago sativa L.

    Science.gov (United States)

    Habben, J E; Volenec, J J

    1990-11-01

    Defoliation of alfalfa (Medicago sativa L.) results in a cyclic pattern of starch degradation followed by reaccumulation in taproots. Characterization of changes in anatomical distribution of starch grains in taproots will aid our understanding of biochemical and physiological mechanisms involved in starch metabolism in taproots of this species. Our objectives were to determine the influence of defoliation on starch grain distribution and size variation in taproots of two alfalfa lines selected for contrasting concentrations of taproot starch. In addition, we used electron microscopy to examine the cellular environment of starch grains, and computer-based image optical analysis to determine how cross-sectional area of tissues influenced starch accumulation. Taproots of field-grown plants were sampled at defoliation and weekly thereafter over a 28-day period. Taproot segments were fixed in glutaraldehyde and prepared for either light or electron microscopy. Transverse sections were examined for number and size of starch grains and tissue areas were measured. Starch grains were located throughout bark tissues, but were confined primarily to ray parenchyma cells in wood tissues. During the first week of foliar regrowth after defoliation, starch grains in ray cells near the cambium disappeared first, while degradation of those near the center of the taproot was delayed. During the third and fourth weeks of regrowth, there was a uniform increase in number of starch grains per cell profile across the rays, but by 28 days after defoliation there were more starch grains in ray cells near the cambium than in cells near the center of the taproot (low starch line only). Bark tissues from both lines showed synchronous degradation and synthesis of starch grains that was not influenced greatly by cell location. Diameter of starch grains varied with cell location in medullary rays during rapid starch degradation, but was not influenced by cell position in bark tissues. Therefore

  7. Inoculação microbiana da silagem de alfafa (Medicago sativa e seu efeito sobre o consumo de matéria seca e sobre a fermentação ruminal em bovinos - DOI: 10.4025/actascianimsci.v25i2.2074 Microbial inoculation of alfalfa silage (Medicago sativa and its effect on dry matter intake and ruminal fermentation in bovines - DOI: 10.4025/actascianimsci.v25i2.2074

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Mazza Rodrigues

    2003-04-01

    Full Text Available O objetivo do presente estudo foi avaliar os efeitos da inoculação microbiana da alfafa (Medicago sativa para ensilagem sobre o consumo de matéria seca, fermentação ruminal e taxa de passagem de líquidos em bovinos. Doze vacas não-gestantes e não-lactantes foram distribuídas em um delineamento em blocos, e os tratamentos corresponderam à silagem pré-secada de alfafa (60% de MS e 19,5% de PB controle ou inoculada com o produto Silobac® (Lactobacillus plantarum e Pediococcus pentosaceus. A dieta experimental continha 50% de silagem de alfafa e 50% de concentrado. O experimento teve duração total de 21 dias, sendo o 21º dia utilizado para colheitas de líquido ruminal realizadas às 0h, 2h, 4h, 6h, 8h, 10h e 12h, após a 1a refeição. A inoculação microbiana da silagem de alfafa não alterou o consumo de MS (inoculada = 2,56 vs. controle = 2,39% PV, o pH do líquido ruminal (6,15 vs. 6,27, a concentração ruminal de N-NH3 (19,0 vs. 18,2mg/dl, a concentração total de AGVs (122,5 vs. 113,8mM ou a proporção molar de ácido acético (66,1 vs. 66,8% molar, propiônico (21,1 vs. 19,6% molar e butírico (12,8 vs. 13,6% molar. Parâmetros relativos à dinâmica líquida ruminal, como o volume líquido (59,5 vs. 63,4 litros e a taxa de passagem de líquidos (8,6 vs. 8,0%/h, também não foram alterados com a inoculação.The objective of this study was to evaluate the effects of microbial inoculation of alfalfa (Medicago sativa for ensiling on dry matter intake, ruminal fermentation and liquid passage rate in twelve non pregnant dry cows. A randomized block design was used and the treatments were alfalfa haylage control (60% DM and 19.5% CP or inoculated with Silobac® product (Lactobacillus plantarum and Pediococcus pentosaceus. Experimental diet contained 50% of alfalfa silage and 50% of concentrate. Experimental period lasted for twenty-one days; the 21st day was used for ruminal liquid sampling at 0, 2, 4, 6, 8, 10 e 12 hours

  8. Triterpenoid glycosides from Medicago sativa as antifungal agents against Pyricularia oryzae.

    Science.gov (United States)

    Abbruscato, Pamela; Tosi, Solveig; Crispino, Laura; Biazzi, Elisa; Menin, Barbara; Picco, Anna M; Pecetti, Luciano; Avato, Pinarosa; Tava, Aldo

    2014-11-19

    The antifungal properties of saponin mixtures from alfalfa (Medicago sativa L.) tops and roots, the corresponding mixtures of prosapogenins from tops, and purified saponins and sapogenins against the causal agent of rice blast Pyricularia oryzae isolates are presented. In vitro experiments highlighted a range of activities, depending upon the assayed metabolite. The antifungal effects of the most promising prosapogenin mixture from alfalfa tops were confirmed by means of in planta tests using three different Italian cultivars of rice (Oryza sativa L. ssp. japonica), known to possess high, medium, and low blast resistance. The evidenced antifungal properties of the tested metabolites allowed some considerations on their structure-activity relationship. Results indicate that prosapogenins are active compounds to prevent the fungal attack of P. oryzae on different rice cultivars. Therefore, if properly formulated, these substances could represent a promising and environmentally friendly treatment to control rice blast.

  9. Análisis de la variabilidad de caracteres de raíz en poblaciones de alfalfa (Medicago sativa L.) con alto número de raíces laterales Root traits variability in alfalfa (Medicago sativa L.) populations with a high number of lateral roots

    OpenAIRE

    A. Odorizzi; D. Basigalup; V. Arolfo; M. Balzarini

    2008-01-01

    Para atenuar el daño provocado por los gorgojos de la alfalfa en la Argentina, el mejoramiento orientado al aumento del número de raíces laterales puede ser importante. Los objetivos de este trabajo fueron estimar bajo cuatro condiciones ambientales, componentes de varianza, heredabilidad en sentido amplio (H) y correlaciones entre biomasa aérea y caracteres de raíz en 10 poblaciones de alfalfa de grado 6 a 9 de reposo invernal, mejoradas por sistema de raíz ramificada en la E.E.A. Manfredi-I...

  10. Alfalfa: bioenergy and more

    Science.gov (United States)

    Alfalfa (Medicago sativa) has the potential to be a significant contributor to America's renewable energy future. In an alfalfa biomass energy production system, alfalfa forage would be separated into stem and leave fractions. The stems would be processed to produce energy, and the leaves would be s...

  11. The Hybridization Barrier between Herbaceous Medicago sativa and Woody M. arborea Is Weakened by Selection of Seed Parents

    Directory of Open Access Journals (Sweden)

    Edwin Bingham

    2013-05-01

    Full Text Available Medicago sativa, alfalfa or lucerne, and M. arborea were considered reproductively isolated until recently. Then, in 2003, an alfalfa genotype was identified that produced a few seeds and progeny with hybrid traits after a large number of pollinations by M. arborea. A derivative of this alfalfa genotype also produced a low frequency of progeny with hybrid traits. Thus, the hybridization barrier was weakened by selection of seed parents. Hybrids from both events expressed traits from M. arborea and M. arborea-specific DNA bands, although more of the M. sativa genome was retained, based on the DNA results. Thus, there was chromatin elimination during embryogenesis, resulting in partial hybrids (hereafter hybrids. However, more than 30 hybrids with an array of M. arborea traits have been obtained thus far, and research continues on the nature of the hybrids. Traits have been genetically transmitted in crosses, and selected traits are in use for alfalfa breeding. This paper reviews the first hybrids and then focuses on further weakening of the hybridization barrier with the discovery of a more efficient hybridizer derived from crossing Medicago sativa subspecies, sativa, coerulea and falcata. This genotype was found to have reproductive abnormalities associated with its complex subspecies origin that are best described as hybrid breakdown. In effect, this subspecies derivative is a bridge-cross parent that consistently produces hybrids. Reproductive abnormalities in the bridge-cross parent are reported and discussed.

  12. [Physical localization of ribosomal genes and chromosome DAPI banding by in situ hybridization in Medicago sativa L].

    Science.gov (United States)

    Chen, Jian-Min; Hong, Yi-Huan; Wang, You-Ping; Bowley, Steve; Wan, Jian-Min

    2006-02-01

    Physical localization of ribosomal genes in diploid and tetraploid alfalfa (Medicago. sativa) was studied using fluorescent in situ hybridization (FISH). It was revealed that 45s gene was only located at nucleolus organizer region (NOR) with a single locus in both diploid and tetraploid alfalfa, while 5s gene had 2-3 loci on chromosomes. Using the genomic DNA from M. coerulea and M. falcata as probe to hybridize with tetraploid species in alfalfa, both diploid species were successfully hybridized with tetraploid chromosomes, only showing the difference in hybridization signals in different numbers of chromosomes. Chromosomes of alfalfa exhibited DAPI banding by FISH analysis. In general, the patterns of distribution of DAPI banding were consistent with C-banding for M. coerulea. The possible origination of tetraploid alfalfa was discussed based on DAPI banding patterns and FISH analysis for ribosomal genes .

  13. Análisis de la variabilidad de caracteres de raíz en poblaciones de alfalfa (Medicago sativa L. con alto número de raíces laterales Root traits variability in alfalfa (Medicago sativa L. populations with a high number of lateral roots

    Directory of Open Access Journals (Sweden)

    A. Odorizzi

    2008-12-01

    Full Text Available Para atenuar el daño provocado por los gorgojos de la alfalfa en la Argentina, el mejoramiento orientado al aumento del número de raíces laterales puede ser importante. Los objetivos de este trabajo fueron estimar bajo cuatro condiciones ambientales, componentes de varianza, heredabilidad en sentido amplio (H y correlaciones entre biomasa aérea y caracteres de raíz en 10 poblaciones de alfalfa de grado 6 a 9 de reposo invernal, mejoradas por sistema de raíz ramificada en la E.E.A. Manfredi-INTA. Los caracteres evaluados fueron: rendimiento de biomasa promedio (BP, diámetro de raíz pivotante (DP, número de raíces laterales (NRLR, diámetro de raíces laterales (DRLR y sistema radicular tipo ramificado (R. Hubo ausencia de correlación entre BP y los caracteres de raíz en la mayoría de los ambientes, indicando que se debe seleccionar por ambos caracteres en forma específica e individual. En ambientes con riego, DP fue el que más se correlacionó con BP (r =0,47; p In order to provide some level of tolerance to the alfalfa root curculio in Argentina, the improvement directed to increasing the number of secondary roots could be important. The objectives of this work were to estimate under four environmental conditions, variance components, trait heritabilities (H and correlations among aerial and root traits in 10 alfalfa populations ranging from 6 to 9 fall dormancy, obtained by the alfalfa breeding program at the Exp. Stn. of Manfredi- INTA. The evaluated traits were average forage yield per cut (BP, taproot diameter (DP, number of lateral roots (NRLR, lateral root diameter (DRLR and branched-type root system (R. Considerable variation for all traits was detected across all environments. There was no correlation between BP and most of root traits in almost every environmental condition, indicating that selection for yield and root traits could be independently managed. Under irrigation, DP was positively (r =0,47; p<0,01 correlated

  14. Characterization and genetic dissection of resistance to spotted alfalfa aphid (Therioaphis trifolii) in Medicago truncatula

    KAUST Repository

    Kamphuis, L. G.

    2013-09-21

    Aphids cause significant yield losses in agricultural crops worldwide. Medicago truncatula, a model legume, cultivated pasture species in Australia and close relative of alfalfa (Medicago sativa), was used to study the defence response against Therioaphis trifolii f. maculate [spotted alfalfa aphid (SAA)]. Aphid performance and plant damage were compared among three accessions. A20 is highly susceptible, A17 has moderate resistance, and Jester is strongly resistant. Subsequent analyses using A17 and A20, reciprocal F1s and an A17×A20 recombinant inbred line (RIL) population revealed that this moderate resistance is phloem mediated and involves antibiosis and tolerance but not antixenosis. Electrical penetration graph analysis also identified a novel waveform termed extended potential drop, which occurred following SAA infestation of M. truncatula. Genetic dissection using the RIL population revealed three quantitative trait loci on chromosomes 3, 6, and 7 involved in distinct modes of aphid defence including antibiosis and tolerance. An antibiosis locus resides on linkage group 3 (LG3) and is derived from A17, whereas a plant tolerance and antibiosis locus resides on LG6 and is derived from A20, which exhibits strong temporary tolerance. The loci identified reside in regions harbouring classical resistance genes, and introgression of these loci in current medic cultivars may help provide durable resistance to SAA, while elucidation of their molecular mechanisms may provide valuable insight into other aphid–plant interactions.

  15. The efficiency of nitrogen fixation of the model legume Medicago truncatula (Jemalong A17) is low compared to Medicago sativa.

    Science.gov (United States)

    Sulieman, Saad; Schulze, Joachim

    2010-06-15

    Medicago truncatula (Gaertn.) (barrel medic) serves as a model legume in plant biology. Numerous studies have addressed molecular aspects of the biology of M. truncatula, while comparatively little is known about the efficiency of N(2) fixation at the whole plant level. The objective of the present study was to compare the efficiency of N(2) fixation of M. truncatula to the genetically closely related Medicago sativa (L.) (alfalfa). The relative growth of both species relying exclusively on N(2) fixation versus nitrate nutrition, H(2) evolution, nitrogen assimilation, the concentration of amino acids and organic acids in nodules, and (15)N(2) uptake and distribution were studied. M. truncatula showed much lower efficiency of N(2) fixation. Nodule-specific activity was several-fold lower when compared to M. sativa, partially as a result of a lower electron allocation to N(2) versus H(+). M. truncatula or M. sativa plants grown solely on N(2) fixation as a nitrogen source reached about 30% or 80% of growth, respectively, when compared to plants supplied with sufficient nitrate. Moreover, M. truncatula had low %N in shoots and a lower allocation of (15)N to shoots during 1h (15)N(2) labeling period. Amino acid concentration was about 20% higher in M. sativa nodules, largely as a result of more asparagine, while the organic acid concentration was about double in M. sativa, coinciding with a six-fold higher concentration of malate. Total soluble protein in nodules was about three times lower in M. truncatula and the pattern of enzyme activity in that fraction was strongly different. Sucrose cleaving enzymes displayed higher activity in M. truncatula nodules, while the activity of phosphoenolpyruvate carboxylase (PEPC) was much lower. It is concluded that the low efficiency of the M. truncatula symbiotic system is related to a low capacity of organic acid formation and limited nitrogen export from nodules.

  16. Studies on Combined Application of 8 kinds of trace element fertilizers in fine production of alfalfa(Medicago sativa L.)%8种微肥配施在紫花苜蓿优质生产中的应用

    Institute of Scientific and Technical Information of China (English)

    郭孝; 介晓磊; 胡华锋

    2006-01-01

    针对河南省土壤微量元素的含量以及紫花苜蓿(Medicago sativa L.)对微量元素需要的特点,该文对锌、铁、铜、锰、硼、钼、钴、硒等八大微肥在紫花苜蓿优质生产中的应用进行了定量的研究,分析和比较不同的微肥配施技术对紫花苜蓿优质生产的关键性的影响,以达到用不同的配施方案,解决不同生产要求的目的.

  17. Isolation and functional characterization of salt-stress induced RCI2-like genes from Medicago sativa and Medicago truncatula.

    Science.gov (United States)

    Long, Ruicai; Zhang, Fan; Li, Zhenyi; Li, Mingna; Cong, Lili; Kang, Junmei; Zhang, Tiejun; Zhao, Zhongxiang; Sun, Yan; Yang, Qingchuan

    2015-07-01

    Salt stress is one of the most significant adverse abiotic factors, causing crop failure worldwide. So far, a number of salt stress-induced genes, and genes improving salt tolerance have been characterized in a range of plants. Here, we report the isolation and characterization of a salt stress-induced Medicago sativa (alfalfa) gene (MsRCI2A), which showed a high similarity to the yeast plasma membrane protein 3 gene (PMP3) and Arabidopsis RCI2A. The sequence comparisons revealed that five genes of MtRCI2(A-E) showed a high similarity to MsRCI2A in the Medicago truncatula genome. MsRCI2A and MtRCI2(A-E) encode small, highly hydrophobic proteins containing two putative transmembrane domains, predominantly localized in the plasma membrane. The transcript analysis results suggest that MsRCI2A and MtRCI2(A-D) genes are highly induced by salt stress. The expression of MsRCI2A and MtRCI2(A-C) in yeast mutants lacking the PMP3 gene can functionally complement the salt sensitivity phenotype resulting from PMP3 deletion. Overexpression of MsRCI2A in Arabidopsis plants showed improved salt tolerance suggesting the important role of MsRCI2A in salt stress tolerance in alfalfa.

  18. Relaciones entre propiedades físicas y químicas del suelo y raíces de alfalfa (Medicago sativa L. afectada por "manchoneo" Relantionships between soil physical and chemical properties and alfalfa (Medicago sativa L. roots in patched soils

    Directory of Open Access Journals (Sweden)

    Elena Bonadeo

    2006-12-01

    Full Text Available El objetivo de este trabajo fue relacionar propiedades físicas y físico-químicas del suelo con el sistema de raíces de un alfalfar para situaciones de desarrollo "normal" (N y de "manchoneo" (M de la pastura. El pH y el porcentaje de sodio intercambiable (PSI aumentan con la profundidad en N y M, siendo más notorio el incremento en M. Un pH de 9 ocurre a los 24 y a los 55 cm, para M y N, respectivamente. En el período comprendido entre noviembre de 2001 y abril de 2002, la mayor conductividad eléctrica medida en N fue de 1,83 dS m-¹ a los 70 cm y en M de 3,92 dS m-¹, a los 30 cm. El menor número total de raíces y la menor profundidad alcanzada en M, en 2001, se atribuyen principalmente a diferencias en el contenido salino, debido a la tolerancia de la alfalfa al elevado PSI. En 2001, hasta los 30 cm, la densidad de longitud de raíces de N superó significativamente a M. En 2002 se observaron diferencias significativas en la profundidad máxima. Se concluye que existe una relación estrecha entre la conductividad eléctrica del suelo y los parámetros radicales evaluados.The objective of this work was to evaluate the soil physical and physical-chemistries properties as related with the development of the alfalfa root system. Two situations were studied: "normal" (N and "patched" (M growth. Exchangeable sodium percentage (ESP and pH increase with the depth in N and M, being more noticeable in M. pH values of 9 occurred at 24 and 55 cm in M and N, respectively. The ESP shows a similar tendency. In the period between November 2001 and April 2002, the highest measured electrical conductivity in N was 1.83 dS m-1 at 70 cm, and in M 3.92 dS m-1 at 30 cm. In 2001, the lower total root number and the shallower depth reached in M, were due to differences in the saline content mainly. This is probably due to the tolerance of the alfalfa to the high ESP. In 2001, the roots length density until 30 cm, was significantly superior in N. In 2002

  19. Evaluación de daño de gorgojos en poblaciones de alfalfa (Medicago sativa L. con alto número de raíces laterales Evaluation of root curculio/weevil damage in alfalfa (Medicago sativa L. populations with large numbers of lateral roots

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    A. S. Odorizzi

    2011-12-01

    Full Text Available El aumento del número de raíces laterales a través del mejoramiento puede ser importante para reducir el daño provocado por el complejo de gorgojos de la alfalfa. El objetivo fue evaluar, en cuatro ambientes (siembras de otoño y primavera con y sin riego, el comportamiento de 10 poblaciones seleccionadas por alto número de raíces laterales. Los caracteres evaluados fueron: categoría (Cat de daño de gorgojos (de 1 = sin daño a 5 = daño severo, rendimiento promedio de forraje (BP, número de raíces secundarias (NRLR y diámetro de raíces laterales (DRLR. Las poblaciones s755, s545 y s614 presentaron los mayores valores de DRLR y NRLR, el menor daño de gorgojos (Cat 2+3 y la mayor variabilidad para los caracteres estudiados. Las poblaciones s545 y s616 exhibieron el mayor DRLR y el menor NRLR, respectivamente. Las condiciones de riego propiciaron un menor daño, y fueron menos afectadas en estos ambientes las poblaciones s545, s614 y s617; por el contrario, las poblaciones s461, s755, s463 resultaron las más afectadas. Los daños más severos (Cat 4+5 se observaron en secano y las poblaciones s618 y s616 fueron las más afectadas; sólo bajo estas condiciones el mayor daño se correlacionó con menor BP.Increasing the number of lateral roots through breeding may be important to reduce the damage caused by the root curculio complex in alfalfa in Argentina. The objective was to evaluate the performance of ten alfalfa experimental populations selected for their large number of lateral roots under four environmental conditions (fall and spring planting with or without irrigation. The evaluated traits were curculio damage (Categories (Cat 1 = no damage to 5 = very severe damage, dry matter yield (BP, number of secondary roots (NRLR, and diameter of lateral roots (DRLR. Populations s755, s545 and s614 had the highest values for DRLR and NRLR, the least damage from weevil (Cat 2 +3, and the largest variability (mean square for all the

  20. Influencia del agregado de enmiendas básicas sobre la producción de alfalfa (Medicago sativa L. en ámbitos templados argentinos Basic amendment application effects on alfalfa production in Argentine temperate areas

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    Mabel Vázquez

    2010-12-01

    ,1-0,9 unidad de pH en la capa superficial. La capacidad de intercambio catiónica aumentó de 0,2 a 5,3 cmol kg-1, y el Ca intercambiable hasta un máximo de 2,6 cmol kg-1. Se registró un efecto negativo del encalado sobre el contenido de P extractable, sugiriendo la necesidad de acompañar la práctica con diagnósticos de este elemento.Natural and anthropic factors may produce soil acidification in temperate areas, causing deficiencies/unbalances of basic nutrients, particularly Ca and Mg. This problem requires regional experimentation to generate regulations for the election of the amendment, rate and application form. The aim of this study was to compare the alfalfa yield of three areas in the argentine temperate region, the basic nutrient concentration in the plants, and the changes in edaphic properties caused by the different rates and types of amendments. Two trials were conducted in Typic Argiudolls and one in an Entic Hapludoll of Buenos Aires, Santa Fe and Córdoba provinces. The treatments consisted in the application of 0 and 700, or 1,000, 1,500 and 2,000 kg ha-1 of shell/calcite and dolomite, according to the site. The effect of the additional application of 200 kg ha-1 of gypsum was evaluated. Alfalfa dry matter yield, foliar concentration of Ca and Mg and the effect of the treatments on edaphic properties were measured. The smaller rates (700-1,000 kg ha-1, with or without gypsum, produced the greatest yield increases. These increases were of 9, 16.5 and 18.8% respect to the control, for the trial of Santa Fe (C1000; 6 harvests, Buenos Aires (C1000, 5 harvests and Córdoba (C700, 10 harvests, respectively, and of 11.7; 14.4 and 9.1% respect to the control, for the trial of Santa Fe (D1000, Buenos Aires (D1000 and Córdoba (D700, respectively. The residuality extended all along the evaluation time (27 months. The treatments did not produce mayor differences in the foliar concentrations of Ca and Mg, although they increased the availability of both nutrients

  1. In silico identification of transcription factors in Medicago sativa using available transcriptomic resources.

    Science.gov (United States)

    Postnikova, Olga A; Shao, Jonathan; Nemchinov, Lev G

    2014-06-01

    Transcription factors (TFs) are proteins that govern organismal development and response to the environment by regulating gene expression. Information on the amount and diversity of TFs within individual plant species is critical for understanding of their biological roles and evolutionary history across the plant kingdom. Currently, only scattered information on separate TFs is available for alfalfa, the most extensively cultivated forage legume in the world. In the meantime, several large transcriptomic resources that can be used to identify and characterize alfalfa TF genes are freely accessible online. In this study, we have performed an in silico analysis of transcriptome data generated in our laboratory and publicly acquirable from other sources to reveal and systematize alfalfa transcription factors. Transcriptome-wide mining enabled prediction of 983 TFs along with their sequence features and putative phylogenies of the largest families. All data were assembled into a simple open-access database named AlfalfaTFDB ( http://plantpathology.ba.ars.usda.gov/alfalfatfdb.html ). Transcriptomic analysis used in this work represents an effective approach for the identification of TF genes in plants with incomplete genomes, such as alfalfa. Integrated TF repertoires of Medicago sativa will provide an important tool for studying regulation of gene expression in other complex non-model species of agricultural significance.

  2. Deep-sequencing transcriptome analysis of field-grown Medicago sativa L. crown buds acclimated to freezing stress.

    Science.gov (United States)

    Song, Lili; Jiang, Lin; Chen, Yue; Shu, Yongjun; Bai, Yan; Guo, Changhong

    2016-09-01

    Medicago sativa L. (alfalfa) 'Zhaodong' is an important forage legume that can safely survive in northern China where winter temperatures reach as low as -30 °C. Survival of alfalfa following freezing stress depends on the amount and revival ability of crown buds. In order to investigate the molecular mechanisms of frost tolerance in alfalfa, we used transcriptome sequencing technology and bioinformatics strategies to analyze crown buds of field-grown alfalfa during winter. We statistically identified a total of 5605 differentially expressed genes (DEGs) involved in freezing stress including 1900 upregulated and 3705 downregulated DEGs. We validated 36 candidate DEGs using qPCR to confirm the accuracy of the RNA-seq data. Unlike other recent studies, this study employed alfalfa plants grown in the natural environment. Our results indicate that not only the CBF orthologs but also membrane proteins, hormone signal transduction pathways, and ubiquitin-mediated proteolysis pathways indicate the presence of a special freezing adaptation mechanism in alfalfa. The antioxidant defense system may rapidly confer freezing tolerance to alfalfa. Importantly, biosynthesis of secondary metabolites and phenylalanine metabolism, which is of potential importance in coordinating freezing tolerance with growth and development, were downregulated in subzero temperatures. The adaptive mechanism for frost tolerance is a complex multigenic process that is not well understood. This systematic analysis provided an in-depth view of stress tolerance mechanisms in alfalfa.

  3. 紫花苜蓿几种主要害虫的化学防治试验%Chemical Control Experiments on the Main Pests in Alfalfa (Medicago sativa L.)

    Institute of Scientific and Technical Information of China (English)

    杨向黎; 韩凤英; 秦旭; 杨慧; 张玉梅

    2014-01-01

    近年来,紫花苜蓿(Medicago sativa)上害虫发生与危害愈来愈严重,直接影响着苜蓿的产量和质量.针对生产中发生量大、为害重的害虫进行了化学农药的精准施药技术的研究,提出了使用噻虫嗪等杀虫剂可有效地防治蓟马(Thripidae)、苜蓿盲蝽(Adelphocoris lineolastus)、叶蝉(Cicadellidae)等刺吸式口器害虫的适用剂量,使用氯虫·高氯氟等杀虫剂防治甜菜夜蛾(Spodoptra exigua)、斜纹夜蛾(Prodenia litura)等咀嚼式口器害虫的适用剂量,为苜蓿生产中害虫的安全用药提供了依据.

  4. Chemical modification and degradation of atrazine in Medicago sativa through multiple pathways.

    Science.gov (United States)

    Zhang, Jing Jing; Lu, Yi Chen; Yang, Hong

    2014-10-08

    Atrazine is a member of the triazine herbicide family intensively used to control weeds for crop production. In this study, atrazine residues and its degraded products in alfalfa (Medicago sativa) were characterized using UPLC-TOF-MS/MS. Most of atrazine absorbed in plants was found as chemically modified derivatives like deisopropylated atrazine (DIA), dehydrogenated atrazine (DHA), or methylated atrazine (MEA), and some atrazine derivatives were conjugated through different functional groups such as sugar, glutathione, and amino acids. Interestingly, the specific conjugates DHA+hGSH (homoglutathione) and MEA-HCl+hGSH in alfalfa were detected. These results suggest that atrazine in alfalfa can be degraded through different pathways. The increased activities of glycosyltransferase and glutathione S-transferase were determined to support the atrazine degradation models. The outcome of the work uncovered the detailed mechanism for the residual atrazine accumulation and degradation in alfalfa and will help to evaluate whether the crop is suitable to be cultivated in the atrazine-polluted soil.

  5. [Quality standard of uygur medicine Medicago sativa seeds].

    Science.gov (United States)

    Ding, Wen-Huan; Xu, Hai-Yan; Wang, Dong-Dong; Li, Jie; Tian, Shu-Ge

    2013-11-01

    In this paper, microscopic identification method was adopted to observe the microscopic characters of ten batches of Medicago sativa seeds. And M. sativa seeds were identificated by TLC method in contrast to trigonelline and stachydrine hydrochloride. The impurities, moisture, ash, sour insoluble ash were detected based on Chinese Pharmacopoeia 2010 version (Vol I ). An HPLC method was also established for determination of trigonelline in the M. sativa seeds. The contents of impurities, moisture, ash, sour insoluble ash should not exceed 5%, 10%, 6%, and 2%, respectively. The content of trigonelline should be not less than 0.795 6 mg x g(-1). The experimental methods were accurate and reliable, and can be used as the quality control of the seeds of M. sativa.

  6. Effects of Cropping Patterns on Soil Aggregates of Alfalfa Field%耕作方式对苜蓿(Medicago sativa)地土壤团粒的影响

    Institute of Scientific and Technical Information of China (English)

    崔星; 师尚礼

    2014-01-01

    以甘肃干旱区连作5年和轮作1年的苜蓿(Medicago sativa)地土壤为研究对象,对不同耕作方式下土壤团粒结构、容重、含水量指标进行研究.结果表明:在轮作和连作模式下,随着土壤深度的增加,>0.25 mm土壤团粒质量在干筛和湿筛处理下均降低,>0.25 mm团粒累积质量越大,分形维数越小.在浸水条件下,粒径为0.5~0.25 mm的土壤团聚体含量最高,其它粒径团聚体含量依粒径的增大而降低.轮作土壤含水量呈现先增加后降低、最后再增加的变化过程;0~60 cm土层水分含量最高(13.881%),60~80 cm土层含水量下降到较低值(10.343%),80~100 cm土层水分迅速恢复(13.811%).连作和轮作土壤容重随土壤深度均呈现依次增大变化,连作最大值为1.425%比最小值高出17.6%,轮作最大值1.432%比最小值高出18.7%.

  7. Physiological and Biochemical Responses of Leaves and Roots of Alfalfa (Medicago sativa L. ) to Water Stress%苜蓿叶片及根系对水分亏缺的生理生化响应

    Institute of Scientific and Technical Information of China (English)

    李文娆; 张岁岐; 山仑

    2007-01-01

    利用PEG-6000模拟研究水分胁迫(ψs=-0.2 MPa)48 h,后复水48 h,阿尔冈金和陇东苜蓿(Medicago sativa L.)品种幼苗根系与叶片的渗透调节作用及抗氧化酶活性的变化.结果表明:叶片的渗透调节能力及抗氧化酶活性均强于根系;受到水分胁迫后,叶片与根系水势、渗透势及饱和渗透势明显下降并随着时间的延长而逐渐降低;但抗氧化酶(SOD、POD和CAT)活性显著增强并随着胁迫的延续而保持高活性;细胞膜相对透性在胁迫中后期逐渐增大,MDA开始累积;叶片脯氨酸、可溶性糖、K+和可溶性蛋白含量随着胁迫时间的延长亦逐渐累积,根系可溶性糖含量逐渐显著升高,脯氨酸含量没有明显变化,而可溶性蛋白和K+含量呈现下降趋势;复水后产生一定的恢复补偿效应,但叶片生理代谢未能恢复到正常水平;陇东与阿尔冈金苜蓿抗氧化酶活性间存在差异,且二者对水分胁迫的适应能力亦略有差别.

  8. Salt stress alters DNA methylation levels in alfalfa (Medicago spp).

    Science.gov (United States)

    Al-Lawati, A; Al-Bahry, S; Victor, R; Al-Lawati, A H; Yaish, M W

    2016-02-26

    Modification of DNA methylation status is one of the mechanisms used by plants to adjust gene expression at both the transcriptional and posttranscriptional levels when plants are exposed to suboptimal conditions. Under abiotic stress, different cultivars often show heritable phenotypic variation accompanied by epigenetic polymorphisms at the DNA methylation level. This variation may provide the raw materials for plant breeding programs that aim to enhance abiotic stress tolerance, including salt tolerance. In this study, methylation-sensitive amplified polymorphism (MSAP) analysis was used to assess cytosine methylation levels in alfalfa (Medicago spp) roots exposed to increasing NaCl concentrations (0.0, 8.0, 12.0, and 20.0 dS/m). Eleven indigenous landraces were analyzed, in addition to a salt-tolerant cultivar that was used as a control. There was a slight increase in DNA methylation upon exposure to high levels of soil salinity. Phylogenetic analysis using MSAP showed epigenetic variation within and between the alfalfa landraces when exposed to saline conditions. Based on MSAP and enzyme-linked immunosorbent assay results, we found that salinity increased global DNA methylation status, particularly in plants exposed to the highest level of salinity (20 dS/m). Quantitative reverse transcription-polymerase chain reaction indicated that this might be mediated by the overexpression of methyltransferase homolog genes after exposure to saline conditions. DNA demethylation using 5-azacytidine reduced seedling lengths and dry and fresh weights, indicating a possible decrease in salinity tolerance. These results suggest that salinity affects DNA methylation flexibility.

  9. Allelopatic effects of cyanobacteria extracts containing microcystins on Medicago sativa-Rhizobia symbiosis.

    Science.gov (United States)

    El Khalloufi, Fatima; Oufdou, Khalid; Lahrouni, Majida; El Ghazali, Issam; Saqrane, Sanaa; Vasconcelos, Vitor; Oudra, Brahim

    2011-03-01

    The eutrophication of water leads to massive blooms of cyanobacteria potentially producers of highly toxic substances: cyanotoxins, especially microcystins (MC). The contamination of water used for irrigation by these toxins, can cause several adverse effects on plants and microorganisms. In this work, we report the phytotoxic effects of microcystins on the development of symbiosis between the leguminous plant Medicago sativa (Alfalfa) and rhizobia strains. The exposure of rhizobial strains to three different concentrations 0.01, 0.05 and 0.1 μg MC ml(-1) led to decrease on the bacteria growth. The strains of rhizobia Rh L1, Rh L2, Rh L3 and Rh L4 reduced their growth to, respectively, 20.85%, 20.80%, 33.19% and 25.65%. The chronic exposure of alfalfa seeds and seedlings to different MC concentrations affects the whole stages of plant development. The germination process has also been disrupted with an inhibition, which reaches 68.34% for a 22.24 μg MC ml(-1). Further, seedlings growth and photosynthetic process were also disrupted. The toxins reduced significantly the roots length and nodule formation and leads to an oxidative stress. Thus, the MCs contained in lake water and used for irrigation affect the development of symbiosis between M. sativa and Rhizobia.

  10. Differential antifungal activity of alfalfa (Medicago santva L. saponins originated from roots and aerial parts for some ornamental plant pathogens

    Directory of Open Access Journals (Sweden)

    Alicja Saniewska

    2013-12-01

    Full Text Available The total saponins isolated from aerial parts and roots of alfalfa (Medicago sativa L. at the concentration of 0,01%, 0,05% and 0,1% showed differential influence on the mycelium growth of Alternaria zinniae, Botrytis cinerea, Botrytis tulipae, Phoma narcissi, Phoma poolensis and Rhizoctonia solani. A higher inhibitory effect on in vitro growth of mycelium of all tested pathogens indicated saponins from roots of alfalfa than from aerial parts. Tested saponins from roots at lhe concentration of 0,1% totally inhibited linear growth of Phoma narcissi, and linear growth of Alternaria zinniae was limited about 67%, Botrytis cinerea about 74%, Botrytis tulipae about 68%, Phoma poolensis about 38%, and Rhizoctonia solani about 74% in comparison to the control. The saponins of alfalfa from roots at the concentration of 0,1% and 0,2% applied as preinoculation sprays evidently inhibited the development of Phoma narcissi on Hippeastrum leaves. This dose of aerial saponins of alfalfa did not effect the development of necrotic spots on the leaves.

  11. Comparative Analysis of the Symbiotic Efficiency of Medicago truncatula and Medicago sativa under Phosphorus Deficiency

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    Lam-Son Phan Tran

    2013-03-01

    Full Text Available Phosphorus (P-deficiency is a major abiotic stress that limits legume growth in many types of soils. The relationship between Medicago and Sinorhizobium, is known to be affected by different environmental conditions. Recent reports have shown that, in combination with S. meliloti 2011, Medicago truncatula had a lower symbiotic efficiency than Medicago sativa. However, little is known about how Medicago–Sinorhizobium is affected by P-deficiency at the whole-plant level. The objective of the present study was to compare and characterize the symbiotic efficiency of N2 fixation of M. truncatula and M. sativa grown in sand under P-limitation. Under this condition, M. truncatula exhibited a significantly higher rate of N2 fixation. The specific activity of the nodules was much higher in M. truncatula in comparison to M. sativa, partially as a result of an increase in electron allocation to N2 versus H+. Although the main organic acid, succinate, exhibited a strong tendency to decrease under P-deficiency, the more efficient symbiotic ability observed in M. truncatula coincided with an apparent increase in the content of malate in its nodules. Our results indicate that the higher efficiency of the M. truncatula symbiotic system is related to the ability to increase malate content under limited P-conditions.

  12. Physiological and antioxidant responses of Medicago sativa-rhizobia symbiosis to cyanobacterial toxins (Microcystins) exposure.

    Science.gov (United States)

    El Khalloufi, Fatima; Oufdou, Khalid; Lahrouni, Majida; Faghire, Mustapha; Peix, Alvaro; Ramírez-Bahena, Martha Helena; Vasconcelos, Vitor; Oudra, Brahim

    2013-12-15

    Toxic cyanobacteria in freshwaters can induce potent harmful effects on growth and development of plants irrigated with contaminated water. In this study, the effect of cyanobacteria extract containing Microcystins (MC) on Medicago sativa-rhizobia symbiosis was investigated in order to explore plants response through biomass production, photosynthetic pigment and antioxidant enzymes analysis: Peroxidase (POD), Polyphenoloxidase (PPO) and Catalase (CAT). Alfalfa plants were inoculated with two endosymbiotic rhizobial strains: RhOL1 (MC less sensitive strain) and RhOL3 (MC more sensitive strain), to evaluate the rhizobial contribution on the plant response cultured under cyanobacterial toxins stress. The two rhizobia strains were identified as Ensifer meliloti by sequence analysis of their rrs and atpD genes. The chronic exposure to MC extract showed shoot, root and nodules dry weight decrease, in both symbiosis cultures. The rate of decline in plants inoculated with RhOL3 was higher than that in symbiosis with RhOL1 mainly at 20 μg L(-1) of MC. Cyanotoxins also reduced photosynthetic pigment content and generated an oxidative stress observed at cellular level. POD, PPO and CAT activities were significantly increased in leaves, roots and nodules of alfalfa plants exposed to MC. These enzyme activities were higher in plants inoculated with RhOL3 especially when alfalfa plants were exposed to 20 μg L(-1) of MC. The present paper reports new scientific finding related to the behavior of rhizobia-M. sativa associations to MC (Microcystins) for later recommendation concerning the possible use of these symbiosis face to crops exposure to MC contaminated water irrigation.

  13. Varianza genética y mapeo molecular de rendimiento y calidad nutricional en familias de medios hermanos en Medicago sativa.

    OpenAIRE

    Galicia Juárez, Marisol

    2012-01-01

    La alfalfa (Medicago sativa L.) es considerada como el cultivo forrajero de mayor importancia en la nutrición de animales domésticos, y se siembra en todo el mundo. A pesar de existir una amplia gama de variedades de alfalfa sembradas en México hay pocos estudios acerca de la variabilidad genética dentro y entre poblaciones criollas, por tanto esta investigación tuvo el objetivo de estimar la variabilidad genética de caracteres cuantitativos agronómicos y de calidad de nutrientes consideran...

  14. Fermentation characteristics and nutritive value of low moisture silage made from mature bermudagrass (C. dactylon) and switchgrass (P. virgatum) in mixture with alfalfa (M. sativa) or treated with urea and plantain (Musa AAB

    Science.gov (United States)

    Two experiments were conducted at the University of Kentucky Spindletop Farm in Lexington, Kentucky between October and November, 2009 to evaluate the effect of different percentages of alfalfa (Medicago sativa) as mixtures in switchgrass (Panicum virgatus) and bermudagrass (Cynodon dactylon) silage...

  15. Stress responses in alfalfa (Medicago sativa L.) 12. Sequence analysis of phenylalanine ammonia-lyase (PAL) cDNA clones and appearance of PAL transcripts in elicitor-treated cell cultures and developing plants.

    Science.gov (United States)

    Gowri, G; Paiva, N L; Dixon, R A

    1991-09-01

    An expression library containing cDNAs derived from transcripts from fungal elicitor-treated alfalfa cell suspension cultures was screened with an antiserum raised against phenylalanine ammonia-lyase (PAL) from alfalfa. A single immunoreactive clone was isolated which encoded a full-length PAL cDNA (APAL1) consisting of a 2175 bp open reading frame, 96 bp 5'-untranslated leader and 128 bp 3'-non-coding region. The deduced amino acid sequence was 86.5% similar to that of the PAL2 gene of bean, and encoded a polypeptide of Mr 78,865. A second PAL cDNA species was isolated, whose 3'-untranslated region was 86% identical to that of APAL1. Southern blot analysis indicated that PAL is encoded by a small multigene family in alfalfa. PAL transcript levels were rapidly and massively induced, and preceded increased PAL extractable activity, on exposure of alfalfa suspension cells to elicitor from baker's yeast. PAL transcripts were most abundant in roots, stems and petioles during growth and development of alfalfa seedlings. These studies provide the basis for an examination of the developmental and environmental control of a key enzyme of phenylpropanoid synthesis in a plant species which is readily amenable to stable genetic transformation.

  16. INCREMENTO EN INVERNADERO DE LA CALIDAD Y CANTIDAD DEL FOLLAJE DE LA ALFALFA (Medicago Sativa L. VARIEDAD FLORIDA 77 CAUSADO POR LA COMBINACIÓN DE FERTILIZACIÓN BIOLÓGICA Y QUÍMICA EN UN SUELO DE LA SERIE BERMEO DE LA SABANA DE BOGOTÁ

    Directory of Open Access Journals (Sweden)

    J. Tovar-Franco

    2006-06-01

    Full Text Available En la Sabana de Bogotá existe la necesidad de incrementar la producción de forrajes que den buen rendimiento, con alta calidad nutricional y que podrían ser un aporte al desarrollo de la industria de concentrados de animales.El objetivo de este trabajo fue establecer el efecto de la inoculación rizobio-hongo micorriza arbuscular (MA sobre la fijación simbiótica de nitrógeno, la absorción de fósforo y el porcentaje de micorrización en alfalfa(Medicago sativa L. en un suelo andept de la serie Bermeo de la Sabana de Bogotá. Se seleccionó la variedad dealfalfa Florida 77 por su adaptabilidad a las condiciones del suelo, la cepa de Rhizobium (Sinorhizobium melilotiGR-4 por su habilidad para mejorar el rendimiento y estimular la fijación simbiótica de nitrógeno en esta variedad y el hongo MA Archaeospora leptoticha por su habilidad para mejorar el rendimiento y estimular la fijación defósforo en esta leguminosa.La inoculación dual (rizobio-hongo MA demostró eficacia de la fertilización biológica, al incrementar significativamente (p<0.05 los efectos del encalado y la fertilización química, aumentando el rendimiento en 26% y al mejorar en el follaje el contenido de nitrógeno (32% y fósforo (28%. Estos resultados destacan el estímulo de los dos microsimbiontes en el aprovechamiento de la fertilización química.La inoculación dual también estimuló la fijación biológica de nitrógeno incrementándose los efectos de la inoculación rizobial al aumentar el rendimiento en 25% y el contenido de nitrógeno del follaje en 22% (p<0.05. También superó el efecto de la inoculación fúngica aumentando el rendimiento en 31% (p<0.05 y la cantidad defósforo absorbido en 34% (p<0.05, demostrándose así los beneficios de la simbiosis tripartita alfalfa-rizobio-hongo MA en este Andisol.

  17. Cloning and characterization of a heat shock protein 70 gene, MsHSP70-1, in Medicago sativa

    Institute of Scientific and Technical Information of China (English)

    Zhishui He; Rong Xie; Yanzhang Wang; Huasong Zou; Jiabi Zhu; Guanqiao Yu

    2008-01-01

    Some members of the heat shock protein 70 (HSP70) family have important functions in organism development. Here, we identified an alfalfa (Medicago sativa L. cv. Algonquin) HSP70 gene, MsHSP70-1, using cDNA array and reverse transcription-polymerase chain reaction. This gene contains a 1947 bp open reading frame encoding a protein of 649 amino acids.This protein contains all conserved domains,motifs.and characteristic sequences of plant HSP70s.The expression of MsHsP70-1 is enhanced in nodule compared withroot,stem,leaf,and flower,and throughout the process of nodule development.Northern hybridization analysis indicated that the expression of MsHSP70-1 in nodule requires the active bacA gene of rhizobia.These results suggested that MsHSP70-1 might play an important role in alfalfa nodule development.

  18. Effect of the inherent variation in the mineral concentration of alfalfa cultivars on aphid populations Efeito da variação inata da concentração de minerais em cultivares de alfafa (Medicago sativa em população de afídeos (Hemiptera: Aphididae

    Directory of Open Access Journals (Sweden)

    Alexandre de Almeida e Silva

    2005-01-01

    Full Text Available Plants have inherent variability of mineral content which affects their physiology and consequently the herbivorous insects feeding on them. Besides, insects need considerable amounts of potassium, phosphorus and magnesium in their diets, whereas little calcium, sodium and chloride are required. In this study, the inherent variation on mineral (Ca, S, Mg, N, P, K and also C:N ratio concentrations and aphid (Acyrthosiphon spp., Therioaphis maculata, Aphis craccivora populations on three alfalfa (Medicago sativa cultivars (P3; Crioula, the most widely cultivated in Brazil, and CUF 101, an aphid-resistant were studied between September/1997 and August/1998. A significant variation on mineral concentrations and aphid populations was observed among different sampling times and cultivars. The correlations between C:N ratio, Mg, N, P and S concentrations and aphid density variation suggest that the mineral status affects aphid population dynamics under field conditions.As plantas têm variação inata do conteúdo de minerais e seu estado nutricional afeta sua fisiologia cloretos. A variação inata na concentração de minerais (Ca, S, Mg, N, P, K e também a razão C:N e na população de afídeos (Acyrthosiphon spp., Therioaphis maculata, Aphis craccivora em três cultivares de alfafa (M. sativa - P3; Crioula, as mais cultivadas no Brasil, e CUF 101, resistente a afídeos - foi estudada entre setembro/1997 a agosto/1998 neste trabalho. A concentração de minerais e as populações de pulgões variaram significativamente entre os diferentes períodos de coleta e cultivares. As correlações encontradas entre as concentrações de Mg, N, P, S e a razão C:N e a variação no número de pulgões sugerem que os minerais da planta afetam a dinâmica populacional dos pulgões em campo.

  19. Investigation of trace level binding of PtCl{sub 6} and PtCl{sub 4} to alfalfa biomass (Medicago sativa) using Zeeman graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Parsons, J.G.; Gardea-Torresdey, J.L.; Tiemann, K.J.; Gamez, G

    2002-02-12

    Batch laboratory experiments were performed to investigate the effects of pH, chemical modification, time dependency, and interference studies on the binding of trace concentrations of hexachloroplatinate(IV) and tetrachloroplatinate(II) to alfalfa biomass. The pH profiles were measured between pH 2.0 and 6.0. It was found that the binding of trace concentrations of platinum(IV and II) to alfalfa biomass was dependent on pH with a maximum binding occurring at pH 3.0 and a minimum at pH 6.0. When the alfalfa biomass was chemically modified (esterified), maximum binding occurred at pH 6.0 for both oxidation states of platinum. From the batch time dependency experiments, it was found that binding took at least 20 min to level off for both platinum oxidation states. Batch experiments were performed with various concentrations of calcium, magnesium, and sodium (0.1, 1.0, 10, 100 and 1000 ppm) and it was found that calcium affected the binding of platinum(II and IV) to the alfalfa biomass. It was determined that magnesium and sodium did not interfere appreciably with the binding of platinum in either of the oxidation states studied. Finally, batch experiments were performed with Mg{sup 2+}, Ca{sup 2+} and Na{sup +} in solutions at various concentrations, and it was observed that the binding was affected similarly to that by calcium alone.

  20. Spectinomycin resistance mutations in the rrn16 gene are new plastid markers in Medicago sativa.

    Science.gov (United States)

    Dudas, Brigitta; Jenes, Barnabas; Kiss, Gyorgy Botond; Maliga, Pal

    2012-11-01

    We report here the isolation of spectinomycin-resistant mutants in cultured cells of Medicago sativa line RegenSY-T2. Spectinomycin induces bleaching of cultured alfalfa cells due to inhibition of protein synthesis on the prokaryotic type 70S plastid ribosomes. Spontaneous mutants resistant to spectinomycin bleaching were identified by their ability to form green shoots on plant regeneration medium containing selective spectinomycin concentrations in the range of 25-50 mg/l. Sequencing of the plastid rrn16 gene revealed that spectinomycin resistance is due to mutations in a conserved stem structure of the 16S rRNA. Resistant plants transferred to the greenhouse developed normally and produced spectinomycin-resistant seed progeny. In light of their absence in soybean, a related leguminous plant, the isolation of spectinomycin-resistant mutants in M. sativa was unexpected. The new mutations are useful for the study of plastid inheritance, as demonstrated by detection of predominantly paternal plastid inheritance in the RegenSY-T2 × Szapko57 cross, and can be used as selective markers in plastid transformation vectors to obtain cisgenic plants.

  1. Evaluation of Medicago sativa L. sprouts as antihyperlipidemic and antihyperglycemic agent.

    Science.gov (United States)

    Seida, Ahmed; El-Hefnawy, Hala; Abou-Hussein, Dina; Mokhtar, Fatma Alzahraa; Abdel-Naim, Ashraf

    2015-11-01

    Medicago sativa L. (Alfalfa) is traditionally used to treat diabetes. This study was designed to investigate the potential antihyperlipidemic and antihyperglycemic activity of M. sativa sprouts in streptozotocin (STZ) induced diabetes via i.p. injection of 55 mg/kg of STZ. Experimental animals were divided into the following groups: GP1 (normal), GP2 (STZ-hyperlipidemic), GP3 (rouvastatin), GP4 (metformin), GP 5-9 (diabetic treated with methanolic, petroleum ether, chloroform, ethyl acetate and butanol extracts). The administration of the total methanolic extract (500 mg/kg), the petroleum ether (32.5mg) and butanol fractions (60 mg) for 4 weeks significantly decreased (p<0.05) triglycerides (TG), total cholesterol (TC), low-density lipoproteins (LDL) and very low density lipoproteins (VLDL) in comparison to rouvastatin. Petroleum ether fraction proved to exhibit the best activity as antihyperlipidemic agent (12.23%). On the other hand, ethyl acetate fraction retained the best activity (vs. metformin) as antihyperglycemic agent. Histopathological evidences on liver, pancreas and spleen were in agreement with the above mentioned results. Purification, characterization, and identification of isolated compounds from the active fractions afforded 9 compounds: β-sitosterol and stigmasterol from the petroleum ether fraction; 10-hydroxy-coumestrol, apigenin, genistein, p-hydroxy-benzoic-acid, 7, 4'- dihydroxyflavone, quercetin-3-glucoside and sissotrin from the ethyl acetate fraction.

  2. Comparative drought response in eleven diverse alfalfa accessions

    Science.gov (United States)

    Alfalfa (Medicago sativa L.) production is often negatively affected by drought stress. This is particularly true for alfalfa that is cultivated on rangeland. Thus, the development of drought-tolerant alfalfa cultivars is of great significance. A greenhouse study was conducted to evaluate 11 alfa...

  3. Alfalfa -- a sustainable crop for biomass energy production

    Science.gov (United States)

    Alfalfa (Medicago sativa) has the potential to be a significant contributor to America's renewable energy future. In an alfalfa biomass energy production system, alfalfa forage would be separated into stem and leave fractions. The stems would be processed to produce energy, and the leaves would be s...

  4. The coupling of the plant and microbial catabolisms of phenanthrene in the rhizosphere of Medicago sativa.

    Science.gov (United States)

    Muratova, Anna; Dubrovskaya, Ekaterina; Golubev, Sergey; Grinev, Vyacheslav; Chernyshova, Marina; Turkovskaya, Olga

    2015-09-01

    We studied the catabolism of the polycyclic aromatic hydrocarbon phenanthrene by four rhizobacterial strains and the possibility of enzymatic oxidation of this compound and its microbial metabolites by the root exudates of alfalfa (Medicago sativa L.) in order to detect the possible coupling of the plant and microbial metabolisms under the rhizospheric degradation of the organic pollutant. A comparative study of phenanthrene degradation pathways in the PAH-degrading rhizobacteria Ensifer meliloti, Pseudomonas kunmingensis, Rhizobium petrolearium, and Stenotrophomonas sp. allowed us to identify the key metabolites from the microbial transformation of phenanthrene, including 9,10-phenanthrenequinone, 2-carboxybenzaldehyde, and 1-hydroxy-2-naphthoic, salicylic, and o-phthalic acids. Sterile alfalfa plants were grown in the presence and absence of phenanthrene (0.03 g kg(-1)) in quartz sand under controlled environmental conditions to obtain plant root exudates. The root exudates were collected, concentrated by ultrafiltration, and the activity of oxidoreductases was detected spectrophotometrically by the oxidation rate for various substrates. The most marked activity was that of peroxidase, whereas the presence of oxidase and tyrosinase was detected on the verge of the assay sensitivity. Using alfalfa root exudates as a crude enzyme preparation, we found that in the presence of the synthetic mediator, the plant peroxidase could oxidize phenanthrene and its microbial metabolites. The results indicate the possibility of active participation of plants in the rhizospheric degradation of polycyclic aromatic hydrocarbons and their microbial metabolites, which makes it possible to speak about the coupling of the plant and microbial catabolisms of these contaminants in the rhizosphere.

  5. Comparative gene expression profiles between heterotic and non-heterotic hybrids of tetraploid Medicago sativa

    Directory of Open Access Journals (Sweden)

    Nettleton Dan

    2009-08-01

    Full Text Available Abstract Background Heterosis, the superior performance of hybrids relative to parents, has clear agricultural value, but its genetic control is unknown. Our objective was to test the hypotheses that hybrids expressing heterosis for biomass yield would show more gene expression levels that were different from midparental values and outside the range of parental values than hybrids that do not exhibit heterosis. Results We tested these hypotheses in three Medicago sativa (alfalfa genotypes and their three hybrids, two of which expressed heterosis for biomass yield and a third that did not, using Affymetrix M. truncatula GeneChip arrays. Alfalfa hybridized to approximately 47% of the M. truncatula probe sets. Probe set signal intensities were analyzed using MicroArray Suite v.5.0 (MAS and robust multi-array average (RMA algorithms. Based on MAS analysis, the two heterotic hybrids performed similarly, with about 27% of genes showing differential expression among the parents and their hybrid compared to 12.5% for the non-heterotic hybrid. At a false discovery rate of 0.15, 4.7% of differentially expressed genes in hybrids (~300 genes showed nonadditive expression compared to only 0.5% (16 genes in the non-heterotic hybrid. Of the nonadditively expressed genes, approximately 50% showed expression levels that fell outside the parental range in heterotic hybrids, but only one of 16 showed a similar profile in the non-heterotic hybrid. Genes whose expression differed in the parents were three times more likely to show nonadditive expression than genes whose parental transcript levels were equal. Conclusion The higher proportions of probe sets with expression level that differed from the parental midparent value and that were more extreme than either parental value in the heterotic hybrids compared to a non-heterotic hybrid were also found using RMA. We conclude that nonadditive expression of transcript levels may contribute to heterosis for biomass

  6. Overexpression of vacuolar proton pump ATPase (V-H+-ATPase) subunits B, C and H confers tolerance to salt and saline-alkali stresses in transgenic alfalfa (Medicago sativaL.)

    Institute of Scientific and Technical Information of China (English)

    WANG Fa-wei; CHEN Xi-feng; WANG Zhen-min; LI Hai-yan; WANG Chao; SUN Yao; WANG Nan; LI Xiao-wei; DONG Yuan-yuan; YAO Na; LIU Xiu-ming; CHEN Huan

    2016-01-01

    The vacuolar proton pump ATPase (V-H+-ATPase), which is a multi-subunit membrane protein complex, plays a major role in the activation of ion and nutrient transport and has been suggested to be involved in several physiological processes, such as cel expansion and salt tolerance. In this study, three genes encoding V-H+-ATPase subunits B (ScVHA-B, GenBank: JF826506), C (ScVHA-C, GenBank: JF826507) and H (ScVHA-H, GenBank: JF826508) were isolated from the halophyte Suaeda corniculata. The transcript levels ofScVHA-B,ScVHA-C andScVHA-H were increased by salt, drought and sa-line-alkali treatments. V-H+-ATPase activity was also examined under salt, drought and saline-alkali stresses. The results showed that V-H+-ATPase activity was correlated with salt, drought and saline-alkali stress. Furthermore, V-H+-ATPase subunits B, C and H (ScVHA-B,ScVHA-C andScVHA-H) fromS. corniculata were introduced separately into the alfalfa genome. The transgenic alfalfa was veriifed by Southern and Northern blot analysis. During salt and saline-alkali stresses, transgenic lines carrying the B, C and H subunits had higher germination rates than the wild type (WT). More free proline, higher superoxide dismutase (SOD) activity and lower malondialdehyde (MDA) levels were detected in the transgenic plants under salt and saline-alkali treatments. Moreover, theScVHA-B transgenic lines showed greater tolerance to salt and saline-alkali stresses than the WT. These results suggest that overexpression ofScVHA-B,ScVHA-C andScVHA-H improves tolerance to salt and saline-alkali stresses in transgenic alfalfa.

  7. Valor nutritivo do capim-elefante (Penninsetum purpureum, Schum, do feno de alfafa (Medicago sativa, L. e do feno de capim coast-cross (Cynodon dactylon (L. Pers. para eqüinos Nutritive value of elephant grass (Penninsetum purpureum, Schum, alfalfa hay (Medicago sativa, L. and coast-cross grass hay (Cynodon dactylon (L. Pers. for horses

    Directory of Open Access Journals (Sweden)

    Maria Izabel Vieira de Almeida

    1999-08-01

    Full Text Available O objetivo deste trabalho foi avaliar o consumo e a digestibilidade aparente dos nutrientes nos alimentos volumosos capim-elefante, feno de alfafa e feno de capim coast-cross em eqüinos adultos. Dezoito éguas adultas da raça Mangalarga Marchador foram distribuídas em delineamento experimental inteiramente casualizado, com três tratamentos, que consistiram em dietas contendo os seguintes alimentos volumosos: T1 - capim-elefante, T2 - feno de alfafa e T3 - feno de capim coast-cross. Os animais foram alimentados ad libitum, duas vezes ao dia. O período experimental constituiu de uma fase de oito dias para adaptação às dietas e cinco dias para a coleta total das fezes. Não houve diferenças no consumo diário de matéria seca (MS das forragens, sendo observados valores médios de 6,27 kg MS, 68,41 g MS/kg0,75 ou 1,51%PV. Os coeficientes médios de digestibilidade aparente do capim-elefante e dos fenos de alfafa e capim coast-cross foram de 43,10; 55,20; e 49,80% para a MS; 41,60; 53,40; e 47,90% para a energia bruta; 24,60; 71,20; e 56,10% para a proteína bruta; e 40,60; 35,50; e 63,30% para a fibra em detergente neutro.The objective of this work was to evaluate the intake and apparent digestibility of nutrients of elephant grass forages, alfalfa and coast-cross grass hays in adult horses. Eighteen adult Mangalarga Marchador mares were allotted to a completely randomized design with three treatments that consisted on diets with the following forages: T1 - elephant grass, T2 - alfalfa hay, T3 - coast-cross grass hay. The animals were ad libitum fed twice a day. The experimental period was constituted by a phase of eight days for diet adaptation and a phase of five days for total collection of feces. There were no differences of forage dry matter intake, with average values of 6.27 kg DM, 68.41 g DM/kg0,75 or 1.51% LW. The average coefficients of apparent digestibility of elephant grass and alfalfa and coast-cross grass hays were 43.10, 55

  8. Alfalfa(Medicago sativa) seeding date selection and sparse-planting seeds production in irrigated area%紫花苜蓿旱区播期选择与灌区稀植化种子生产

    Institute of Scientific and Technical Information of China (English)

    张自和

    2004-01-01

    紫花苜蓿Medicago sativa素有"牧草之王"之称,堪称世界性牧草,在畜牧业生产、农业土壤改良、种植结构优化和生态环境建设等方面都有十分重要的作用.提高紫花苜蓿产草量和种子产量的措施很多,但据观测与研究表明,旱区非灌溉条件下的播期选择和灌区稀植化种子生产的问题常常为生产者所忽视,需要给以特别的关注.

  9. From model to crop: functional analysis of a STAY-GREEN gene in the model legume Medicago truncatula and effective use of the gene for alfalfa improvement.

    Science.gov (United States)

    Zhou, Chuanen; Han, Lu; Pislariu, Catalina; Nakashima, Jin; Fu, Chunxiang; Jiang, Qingzhen; Quan, Li; Blancaflor, Elison B; Tang, Yuhong; Bouton, Joseph H; Udvardi, Michael; Xia, Guangmin; Wang, Zeng-Yu

    2011-11-01

    Medicago truncatula has been developed into a model legume. Its close relative alfalfa (Medicago sativa) is the most widely grown forage legume crop in the United States. By screening a large population of M. truncatula mutants tagged with the transposable element of tobacco (Nicotiana tabacum) cell type1 (Tnt1), we identified a mutant line (NF2089) that maintained green leaves and showed green anthers, central carpels, mature pods, and seeds during senescence. Genetic and molecular analyses revealed that the mutation was caused by Tnt1 insertion in a STAY-GREEN (MtSGR) gene. Transcript profiling analysis of the mutant showed that loss of the MtSGR function affected the expression of a large number of genes involved in different biological processes. Further analyses revealed that SGR is implicated in nodule development and senescence. MtSGR expression was detected across all nodule developmental zones and was higher in the senescence zone. The number of young nodules on the mutant roots was higher than in the wild type. Expression levels of several nodule senescence markers were reduced in the sgr mutant. Based on the MtSGR sequence, an alfalfa SGR gene (MsSGR) was cloned, and transgenic alfalfa lines were produced by RNA interference. Silencing of MsSGR led to the production of stay-green transgenic alfalfa. This beneficial trait offers the opportunity to produce premium alfalfa hay with a more greenish appearance. In addition, most of the transgenic alfalfa lines retained more than 50% of chlorophylls during senescence and had increased crude protein content. This study illustrates the effective use of knowledge gained from a model system for the genetic improvement of an important commercial crop.

  10. Research on Winter Injury and Prevent Techniqu e of Alfalfa (Medicago sativa L.cv.Aohan) in Chifeng Region%赤峰地区敖汉苜蓿冻害及其防御技术

    Institute of Scientific and Technical Information of China (English)

    孙启忠; 桂荣

    2001-01-01

    In Chifeng region,the w inter injury of alfalfa was classifiedinto four kinds:(1)no injury,(2)the injur ed alfalfa regenerating new buds from roots,(3)no regenerating new buds from roo ts,(4)dead plant.The reason of winter injury was that the planting date was late and the roots before overwinter are weak and shallow.Therefore,the measures of early-sowing in good time and shallow-ploughing and covering soil before over winter could efficiently accelerate the growth of seedlings and reduce winter in jury.%敖汉苜蓿在赤峰地区受冻有4种表现,(1)全株未受冻;(2)根颈上端受冻变黑,下端仍能再生新芽;(3)根颈全部和根的部分受冻变黑,不能再生新芽;(4)全株受冻死亡。引起冻害的主要原因是苜蓿播种期晚和根颈入土浅。研究结果表明,越冬前苜蓿具有2个以上分枝,根颈入土深度5cm以上,以及根颈膨大,直径达0.3cm以上者,方能减轻或避免受冻。适时早播或带肥播种,延长苜蓿生长期和促进幼苗生长,同时在封冻前对平作进行浅耕覆土或深开沟冻磨平,均能增加根颈保温层,有效提高苜蓿越冬率。

  11. Peroxidases from root exudates of Medicago sativa and Sorghum bicolor: Catalytic properties and involvement in PAH degradation.

    Science.gov (United States)

    Dubrovskaya, Ekaterina; Pozdnyakova, Natalia; Golubev, Sergey; Muratova, Anna; Grinev, Vyacheslav; Bondarenkova, Anastasiya; Turkovskaya, Olga

    2017-02-01

    Peroxidases from root exudates of sorghum (Sorghum bicolor L. Moench) and alfalfa (Medicago sativa L.) were purified and characterized, and their ability to oxidize native PAHs and PAH-derivatives was evaluated. The obtained data confirm that peroxidases are involved in the rhizosphere degradation of PAHs. Nondenaturing PAGE showed that the peroxidases of both plants were represented by a range of isoforms/isoenzymes (five to eight). Minor forms were lost during further purification, and as a result, the major anionic form from alfalfa root exudates and the major cationic form from those of sorghum were obtained. Both electrophoretically homogeneous peroxidases were monomeric proteins with a molecular weight of about 46-48 kDa. The pH optima and the main catalytic constants for the test substrates were determined. On the basis of their molecular and catalytic properties, the obtained enzymes were found to be typical plant peroxidases. Derivatives of PAHs and potential products of their microbial degradation (9-phenanthrol and 9,10-phenanthrenequinone), unlike the parent PAH (phenanthrene), inhibited the catalytic activity of the peroxidases, possibly indicating greater availability of the enzymes' active centers to these substances. Peroxidase-catalyzed decreases in the concentrations of a number of PAHs and their derivatives were observed. Sorghum peroxidase oxidized anthracene and phenanthrene, while alfalfa peroxidase oxidized only phenanthrene. 1-Hydroxy-2-naphthoic acid was best oxidized by peroxidase of alfalfa. However, quinone derivatives of PAHs were unavailable to sorghum peroxidase, but were oxidized by alfalfa peroxidase. These results indicate that the major peroxidases from root exudates of alfalfa and sorghum can have a role in the rhizosphere degradation of PAHs.

  12. Nitrogen transfer from forage legumes to grass in a systematic planting design. [Medicago sativa; Lotus corniculatus; Phalaris arundinacea

    Energy Technology Data Exchange (ETDEWEB)

    Brophy, L.S.; Heichel, G.H.; Russelle, M.P.

    Alfalfa (Medicago sativa L.) is the most important forage legume in the USA, but N transfer from this or other perennial forage species to companion grasses growing in a mixed sward is poorly understood. Furthermore, interplant distances and legume/grass ratios have seldom been controlled in studies of N transfer from legumes to non-legumes. The objectives of this field study were: (i) to determine the amount of N transferred from alfalfa and birdsfoot trefoil (Lotus carniculatus L.) to reed canarygrass (Phalaris arundinacea L.); (ii) to define conditions of distance and species ratio under which N transfer occurs; (iii) to compare the two legumes for N transfer; and (iv) to determine the effect of grass proximity on legume N/sub 2/ fixation. Legumes were interplanted with grass in single-species rows within km/sup 2/ plots on a Typic hapludoll soil labeled with /sup 15/N. Analysis of herbage showed significantly lower /sup 15/N concentration in grass near legumes than in grass grown alone, and significantly lower /sup 15/N concentration in legumes near grass than legumes in monoculture. Calculations using isotope dilution methods showed that grass derived a maximum of 68% of its N from alfalfa and 79% from trefoil. This N represented 13% of the N/sub 2/ fixed by trefoil and 17% of that fixed by alfalfa. The results indicated that N transfer occurred over a distance of 20 cm with maximum N transfer in areas of high legume/grass ratio. At third harvest, N derived from symbiosis was significantly higher (95% in alfalfa, 92% in trefoil) for legumes grown in mixture with grass than for legumes grown in monoculture (86% in alfalfa, 80% in trefoil). These results indicate that significant N transfer occurred, and that the amount of N transferred was dependent on interspecies distance and legume/grass ratio.

  13. 紫花苜蓿和裸燕麦混贮发酵品质和营养成分分析%Quality of mixed naked oats (Avena nuda)and alfalfa (Medicago sativa)silage

    Institute of Scientific and Technical Information of China (English)

    葛剑; 杨翠军; 杨志敏; 白雪梅; 赵海香; 刘贵河

    2015-01-01

    以新鲜及晾晒后的紫花苜蓿和裸燕麦为原料,分别设计紫花苜蓿单贮、裸燕麦单贮、裸燕麦∶紫花苜蓿=1∶1、裸燕麦∶紫花苜蓿=2∶1及裸燕麦∶紫花苜蓿=1∶2混贮等5个处理,青贮60 d 后,对其感官评分、发酵品质和营养成分等进行分析。结果表明,鲜贮苜蓿在感官评定、V-Score 及 Kaiser 评价体系中表现一般,而晾晒及混合青贮各处理组均能不同程度提高青贮评分。晾晒和混合青贮对发酵品质产生影响,两者显著或极显著降低 pH值、PA(丙酸)、AA(乙酸)、BA(丁酸)和 AN/TN(氨态氮/总氮)含量(P <0.01或 P <0.05),显著或极显著升高LA(乳酸)含量(P <0.01或 P <0.05),其中以裸燕麦∶紫花苜蓿=2∶1降低或升高最明显。晾晒对青贮饲料的干物质、可溶性碳水化合物及粗灰分含量具有显著或极显著影响(P <0.05或 P <0.01),对其他养分含量影响不大(P >0.05)。混合比例对青贮饲料的所有发酵项目均有极显著影响(P <0.01),对粗蛋白质、可溶性碳水化合物及中性洗涤纤维含量具有显著或极显著影响(P <0.05或 P <0.01),对其他养分指标影响不显著(P >0.05)。晾晒和混合青贮的交互作用可显著提高青贮饲料的发酵品质,但对养分含量影响不明显。因此,从青贮后感官评价、发酵品质及养分含量来看,紫花苜蓿和裸燕麦混合青贮品质优于单独青贮,且晾晒相对于鲜贮更易于青贮,而无论晾晒和鲜贮,当裸燕麦∶紫花苜蓿=2∶1时,青贮品质均优于其他各组。%Using sun-dried or fresh alfalfa and naked oats as materials,five silages,including alfalfa silage,na-ked oats silage,three mix silage,(alfalfa∶naked oats =1∶1,alfalfa∶naked oats =1 ∶2 and alfalfa∶naked oats =2 ∶1 ),were prepared.After 60 days ensiling,the sensory

  14. Responsibility of non-stomatal limitations for the reduction of photosynthesis-response of photosynthesis and antioxidant enzyme characteristics in alfalfa (Medicago sativa L.) seedlings to water stress and rehydration

    Institute of Scientific and Technical Information of China (English)

    LI Wenrao; ZHANG Suiqi; SHAN Lun

    2007-01-01

    Water stress by polyethylene glycol (PEG)-6000 solution (Ψs=0.2 MPa,stress time:48 h,rehydration time:48 h) was performed in leaves of two alfalfa cultivar (Long-Dong and Algonquin) seedlings.Gas exchange parameters,chlorophyll fluorescence parameters,activity of antioxidant enzyme and photosynthetic pigment concentrations were measured to investigate the available photosynthetic and antioxidant enzyme response to variable water conditions as well as stomatal and non-stomatal limitations to photosynthesis.The results showed that non-stomatal limitations were responsible for the reduction of photosynthesis during water stress.At the beginning of water stress (12 h),water was lost and then the stomata closed rapidly,which resulted in a decrease of transpiration,net photosynthesis and CO2 diffusion.Therefore,when intercellular CO2 concentration and carboxylation efficiency decrease,water use efficiency and value of stomatal limitation would increase.However,the decline of net photosynthetic rate was faster than transpiration rate.At the same time,the maximal photochemical efficiency,potential activity of PSII reaction center and photochemical quenching of chlorophyll fluorescence declined significantly,the activity of antioxidant enzyme increased rapidly and the photosynthetic pigment concentrations changed slightly.The results also indicated that,at the initial period of stress,neither oxidative stress nor membrane lipid peroxidation was induced,nor were photosynthetic structures damaged,but photosynthetic functions were partly inhibited.Therefore,the stomatal limitation and non-stomatal limitations had the same responsibility for the reduction of photosynthesis.At the mid-late stage of water stress,net photosynthetic rate,stomatal conductance,maximal photochemical efficiency,potential activity of PSII reaction center and photochemical quenching of chlorophyll fluorescence decreased linearly with the decline of the relative water content.And the relative electron

  15. Genetic Diversity and Population Structure of Chinese and American Alfalfa(Medicago Sativa. L) Germplasm Assessed by SSR Markers%基于SSR标记的中美紫花苜蓿品种遗传多样性研究

    Institute of Scientific and Technical Information of China (English)

    强海平; 余国辉; 刘海泉; 高洪文; 刘贵波; 赵海明; 王赞

    2014-01-01

    mtic188、bf111、afctt1、bf641851、maa660456、aw361等位点上表现较高的遗传多样性,表明这些位点可以较好地反映中美紫花苜蓿品种的遗传多样性,适用于中美紫花苜蓿品种的遗传多样性检测。就不同染色体而言,第二条和第八条染色体上分布的SSR标记揭示的遗传多样性较高,而第一条相对较低。基于混合模型的方法对紫花苜蓿全体基因型进行群体结构分析,两种不同方法均显示确定最优的群体数K值为2,中美两国16个紫花苜蓿品种共100个基因型个体基本按照来源分为两个亚群体,群体间有少量混杂的情况发生。主成分分析和聚类分析与群体结构的分析结果相一致。中国紫花苜蓿品种多样性略高于美国,但差异不显著。中美两国紫花苜蓿材料蕴含了比较丰富的遗传变异,显示了较高水平的基因多样性。中美群体间的遗传多样性水平存在一定的差异,中国紫花苜蓿种质多样性水平略高于美国。群体结构不严格按照来源国家的划分而区分,这一现象与紫花苜蓿异花授粉与广泛的基因交流有着密切的关系。%Objective Alfalfa is the most important cultivated forage across the world. However, for little improvement in forage yield and quality in recent years, conventional breeding methods are far from satisfying the practical need. On the one hand, the improvement in cultivars relies on the quantity of breeding resources, on the other hand, it relies on the understanding of the genetic basis of agronomic traits. Based on SSR markers, the study was conducted to analyze the genetic diversity and population structure of the germplasm from China and the United States and provide basic information on mining beneficial markers and alleles significantly associated with important quantitative and quality traits of alfalfa when using genome-wide association study to facilitate breeding process.[Method]In total, 40

  16. Analysis of Cell Wall-Related Genes in Organs of Medicago sativa L. under Different Abiotic Stresses.

    Science.gov (United States)

    Behr, Marc; Legay, Sylvain; Hausman, Jean-Francois; Guerriero, Gea

    2015-07-16

    Abiotic constraints are a source of concern in agriculture, because they can have a strong impact on plant growth and development, thereby affecting crop yield. The response of plants to abiotic constraints varies depending on the type of stress, on the species and on the organs. Although many studies have addressed different aspects of the plant response to abiotic stresses, only a handful has focused on the role of the cell wall. A targeted approach has been used here to study the expression of cell wall-related genes in different organs of alfalfa plants subjected for four days to three different abiotic stress treatments, namely salt, cold and heat stress. Genes involved in different steps of cell wall formation (cellulose biosynthesis, monolignol biosynthesis and polymerization) have been analyzed in different organs of Medicago sativa L. Prior to this analysis, an in silico classification of dirigent/dirigent-like proteins and class III peroxidases has been performed in Medicago truncatula and M. sativa. The final goal of this study is to infer and compare the expression patterns of cell wall-related genes in response to different abiotic stressors in the organs of an important legume crop.

  17. Research on Transformation of DHN Gene from Ammopiptanthus mongolicus into Alfalfa(Medicago sativa L.)%沙冬青脱水素基因转化紫花苜蓿的研究

    Institute of Scientific and Technical Information of China (English)

    聂利珍; 郭九峰; 孙杰; 孙国琴; 刘永志

    2012-01-01

    为获得抗旱性较强的转基因苜蓿植株,以紫花苜蓿品种中苜2号作为基因转化受体,通过对外植体选择、菌液浓度、选择压确定、侵染时间和共培养时间等因素进行优化,成功建立了农杆菌介导的遗传转化体系.在此基础上,将沙冬青脱水素基因通过农杆菌的介导,转化到中苜2号中.试验结果显示,子叶和下胚轴作为外植体愈伤组织诱导频率最高,可达100%;获得抗性愈伤组织与转基因植株的卡那霉素最佳筛选浓度为25mg/L;外植体与农杆菌的共培养时间以5d为最佳.试验共获得126株T0抗性株,PCR检测30株表现为阳性,表明脱水素基因已转入受体植株中.%In order to obtain transgenic plants of resistant drought,by comparative analysis on the different ex-plant tissues, concentrations of Agrobacterium and kanamycin, time of inoculation and coculture , etc , an Agrobacteri-um-mediated transformation for an alfalfa variety Zhongmu No. 2 was established. On the basis of the transformation, dehydrin of Ammopiptanthus mongolicus was transformated into genome of Zhongmu No. 2 by A. tumefaciens- mediated. The results showed that cotyledon and hypocotyl was the best explant for callus induction and transformation. The optimal kanamycin concentration for selection of resistant callus and transgenic plant was 25 mg/L in the selection medium. The explants and bacteria was cocultured for 5 d. One hundred and twenty-six independent resistant plants were obtained, 30 plants were confirmed to be transgenic by PCR amplification of AmDHN gene and 355 gene.

  18. Toxic effects of arsenic on Sinorhizobium-Medicago sativa symbiotic interaction

    Energy Technology Data Exchange (ETDEWEB)

    Pajuelo, Eloisa [Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, 41012 Seville (Spain); Rodriguez-Llorente, Ignacio D. [Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, 41012 Seville (Spain)], E-mail: irodri@us.es; Dary, Mohammed; Palomares, Antonio J. [Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, 41012 Seville (Spain)

    2008-07-15

    Recently, the Rhizobium-legume symbiotic interaction has been proposed as an interesting tool in bioremediation. However, little is known about the effect of most common contaminants on this process. The phytotoxic effects of arsenic on nodulation of Medicago sativa have been examined in vitro using the highly arsenic resistant and symbiotically effective Sinorhizobium sp. strain MA11. The bacteria were able to grow on plates containing As concentrations as high as 10 mM. Nevertheless, as little as 25-35 {mu}M arsenite produced a 75% decrease in the total number of nodules, due to a 90% reduction in the number of rhizobial infections, as could be determined using the strain MA11 carrying a lacZ reporter gene. This effect was associated to root hair damage and a shorter infective root zone. However, once nodulation was established nodule development seemed to continue normally, although earlier senescence could be observed in nodules of arsenic-grown plants. - First steps of nodulation of alfalfa, in particular infection thread formation, are more sensitive to As than nitrogen fixation due to plant effects.

  19. WATER DEFICIT EFFECT ON YIELD AND FORAGE QUALITY OF MEDICAGO SATIVA POPULATIONS UNDER FIELD CONDITIONS IN MARRAKESH AREA (MOROCCO

    Directory of Open Access Journals (Sweden)

    Mohamed FARISSI

    2014-06-01

    Full Text Available The present study focused the effect of water deficit on agronomic potential and some traits related to forage quality in plants of Moroccan Alfalfa (Medicago sativa L. populations (Taf 1, Taf 2, Dem and Tata originated from Oasis and High Atlas of Morocco and an introduced variety from Australia (Siriver. The experiment was conducted under field conditions in experimental station of INRA-Marrakech and under two irrigation treatments. The first treatment was normal irrigation, providing an amount of water corresponding to the potential evapo-transpiration of the crop, and the second treatment was water deficit stress (one irrigation per cut. For each treatment, the experiment was conducted as a split plot based on a randomized complete block design with four replications. The plants were measured and analyzed over three cuts. Some agronomic traits as, plant height, fresh and dry forage yields were measured. The forage quality was evaluated by leaf:stem ratio and the contents of plants in proteins and nitrogen. The results indicated that the water deficit has negatively affected the plant height and forage yield. The decrease in leaf:stem ratio was observed under water deficit conditions. However, the proteins and nitrogen contents were unaffected. The behavior of tested alfalfa genotypes was significantly different. The Moroccan alfalfa populations were more adapted to water deficit conditions comparatively to Siriver variety and the Tata population was the most adapted one.

  20. Sexual Polyploidization in Medicago sativa L.: Impact on the Phenotype, Gene Transcription, and Genome Methylation

    Directory of Open Access Journals (Sweden)

    Daniele Rosellini

    2016-04-01

    Full Text Available Polyploidization as the consequence of 2n gamete formation is a prominent mechanism in plant evolution. Studying its effects on the genome, and on genome expression, has both basic and applied interest. We crossed two diploid (2n = 2x = 16 Medicago sativa plants, a subsp. falcata seed parent, and a coerulea × falcata pollen parent that form a mixture of n and 2n eggs and pollen, respectively. Such a cross produced full-sib diploid and tetraploid (2n = 4x = 32 hybrids, the latter being the result of bilateral sexual polyploidization (BSP. These unique materials allowed us to investigate the effects of BSP, and to separate the effect of intraspecific hybridization from those of polyploidization by comparing 2x with 4x full sib progeny plants. Simple sequence repeat marker segregation demonstrated tetrasomic inheritance for all chromosomes but one, demonstrating that these neotetraploids are true autotetraploids. BSP brought about increased biomass, earlier flowering, higher seed set and weight, and larger leaves with larger cells. Microarray analyses with M. truncatula gene chips showed that several hundred genes, related to diverse metabolic functions, changed their expression level as a consequence of polyploidization. In addition, cytosine methylation increased in 2x, but not in 4x, hybrids. Our results indicate that sexual polyploidization induces significant transcriptional novelty, possibly mediated in part by DNA methylation, and phenotypic novelty that could underpin improved adaptation and reproductive success of tetraploid M. sativa with respect to its diploid progenitor. These polyploidy-induced changes may have promoted the adoption of tetraploid alfalfa in agriculture.

  1. Genomic Analysis of Verticillium Wilt Resistance and Drought Tolerance in Alfalfa

    Science.gov (United States)

    Alfalfa (Medicago sativa L.) is the fourth largest crop in the United States. Changing trends to multipurpose uses increases demand for alfalfa. However, the production of alfalfa is challenged by endemic and emerging diseases and adverse environmental factors. Identification of genes/loci controlli...

  2. Stand age affects fertilizer nitrogen response in first-year corn following alfalfa

    Science.gov (United States)

    The amount of N that alfalfa (Medicago sativa L.) provides to subsequent first-year corn (Zea mays L.) depends, in part, on the age of alfalfa at termination. Our objective was to determine how alfalfa stand age affects N availability and fertilizer N requirements for first-year corn. Fertilizer N w...

  3. Enhancing pollination by attracting & retaining leaf cutting bees (Megachile rotundata) in alfalfa seed production fields

    Science.gov (United States)

    The alfalfa leafcutting bee, Megachile rotundata (F.), has become an important managed pollinator of alfalfa, Medicago sativa L. One problem when using alfalfa leafcutting bees as managed pollinator, is the dispersal of many females upon release, even when adequate nesting sites are present. While d...

  4. Chemical characterisation of bioactive compounds in Medicago sativa growing in the desert of Oman.

    Science.gov (United States)

    Hanif, Muhammad Asif; Al-Maskari, Ahmed Yahya; Al-Sabahi, Jamal Nasser; Al-Hdhrami, Ibtisam; Khan, Muhammad Mumtaz; Al-Azkawi, Ahlam; Hussain, Abdullah Ijaz

    2015-01-01

    Medicago sativa Linn growing in Omani desert were chemically characterised using flame photometry, inductively coupled plasma, gas chromatography-mass spectrometry and high performance liquid chromatographic (HPLC) analysis. HPLC analyses were performed to determine the phenolics and flavonoids present in M. sativa. The major compounds detected in M. sativa leaves were protchaechenic acid (3.22%), hydroxyl benzoic acid (1.05%), β-Phenyl caffate (0.97%) and kaempherol (0.89%). Pterostilbene, a cholesterol-lowering compound, was detected in M. sativa.

  5. Inhibition of the catalase activity from Phaseolus vulgaris and Medicago sativa by sodium chloride.

    Science.gov (United States)

    Tejera García, Noel A; Iribarne, Carmen; Palma, Francisco; Lluch, Carmen

    2007-08-01

    Changes in catalase activity during the development of the Rhizobium-legume symbiosis as well as its response in salinized plants of Phaseolus vulgaris and Medicago sativa, was studied. Besides, it was examined the behavior of the enzyme, isolated from leaves and root nodules, during in vitro incubation with NaCl doses. Nodule catalase activities of both legumes were assayed with several enzyme inhibitors and also purified. Leaf catalase activity of Phaseolus vulgaris and Medicago sativa decreased and increased respectively throughout the ontogeny, but root nodule catalase kept a high and stable value. This last result suggests that both legumes require the maintenance of high nodule catalase in nitrogen-fixing nodules. Under salt stress conditions leaf and nodule catalase activity decreased in both, grain and pasture legumes. Because catalase from leaf of Medicago sativa and nodules of Phaseolus vulgaris were relatively sensitive to NaCl during in vitro experiments, the detoxifying role of this enzyme for H(2)O(2) should be limited in such conditions. Both catalases, from determinate and indeterminate nodules, were affected neither by oxygen nor superoxide radicals but showed a strong (Phaseolus vulgaris) or partial (Medicago sativa) inhibition with dithiothreitol, dithionite and beta-mercaptoethanol. Besides, cyanide was the most potent inhibitor of nodule catalases. Finally, catalases partially purified by immobilized metal ion affinity chromatography migrated at 42 (Phaseolus vulgaris) and 46kDa (Medicago sativa) on SDS-PAGE, whereas native forms on sephacryl S-300 columns exhibited a molecular mass of 59 and 48kDa (Phaseolus vulgaris) and 88 and 53kDa (Medicago sativa).

  6. 紫外线辐射与土壤干旱胁迫对紫花苜蓿叶表皮蜡质晶体结构及含量的影响%Effect of soil water deficit and enhanced ultraviolet radiation on contents and crystal structure of cuticular waxes in alfalfa (Medicago sativa) leaf

    Institute of Scientific and Technical Information of China (English)

    郭彦军; 郭芸江; 唐华; 李智燕; 韩龙

    2011-01-01

    Enhanced ultraviolet radiation induced by human activities widely influenced plant adaptation, which accompanied with drought stress severely reduced crop yields. In the current study, two alfalfa (Medicago sati-va) cultivars with different drought resistances, Aohan (high resistance) and Sanditi (low resistance), were used to analyze the responses of leaf cuticular wax content and crystal structure, leaf water potential (LWP) , and ultraviolet absorbing compounds under soil water deficit and enhanced ultraviolet radiation (UVR) stresses. The results showed that the leaf wax content in Aohan was significantly higher than that in Sanditi. Compared to well-watered plants, leaf wax content and LWP in Aohan with combined treatments of UVR and soil water deficit increased, while LWP in Sanditi changed insignificantly. This indicates that high-drought resistant cultivar might maintain higher level of LWP to control water loss by increasing wax deposition on leaf surface. Under the conditions of 0. 05 W/m2 UVR dose or combined treatments of UVR and soil water deficit, the platelet wax crystalloid on leaf surface of both alfalfa cultivars melted, which increased covering areas and UVR reflection rate, and thus would reduce cuticular water loss. Under 0. 1 W/m2 UVR dose, some crystal platelets paralleling leaf surface while vertically distributing above other crystalloid, appeared on leaf surface of Aohan, which efficiently reduced the effect of UVR on plant physiology, while the wax crystalloids of Sanditi further melted. The structure of wax crystalloids had no significant response to solely water deficit treatment. The contents of ultraviolet absorbing compounds had no significant response to enhanced UVR, indicating that the wax crystalloid structure on alfalfa leaf surface had direct defense mechanism to UVR, which partly might delay or replace the defense mechanisms from secondary metabolic compound such as ultraviolet absorbing compounds.%选用紫花苜蓿强抗旱

  7. Medicago sativa L. cv. Longmu 807 Breeding Report%龙牧807苜蓿选育报告

    Institute of Scientific and Technical Information of China (English)

    李红; 杨伟光; 黄新育; 杨曌; 毛小涛

    2011-01-01

    Medicago sativa L. cv. Longmu 807, a forage crop cultivar selected from initial population of Medicago sativa L. cv. Longmu 803, had been bred through 12 successive generations by choosing good single plant in the initial population, then asexual propagation and three time mixed choice as well as open pollination. The new cultivar had been checked by comparative tests of varieties, regional test and production test in different ecological zones. The plant is erect and the plant height reached 75.7~105.3 cm in flowering stage and 98.5~133.8 cm in maturity stage. The growing period was about 120 days and turned green during late April in Heilongjiang. The average hay yield was 11739.14 kg ·hm-2 and increased 17.10% compared with control alfalfa Longmu 803(9797.99 kg · hm-2). The average seed yield was 284.60 kg · hm-2, increased 18.25% compared with control alfalfa Longmu 803(230.00 kg ·bm-2). The alfalfa Longmu 807 has good palatability and its crude protein contents are 19.38% at early flowering stage.Moreover, the plant has strong resistance ability and ecological adapt ability. It is suitable to be cultivated in HeiLongjiang or other province around HeiLongjiang.%从龙牧803(Medicago sativa L.cv.Longmu 803)苜蓿群体中选择优秀单株,通过无性扦插繁殖,3次混合选择、开放授粉及品种比较试验、区域与生产试验,历经12年育成龙牧807苜蓿(Medicago sativa L.cv.Longmu 807)新品种.该品种株型直立,在黑龙江省地区4月中下旬返青,生育期120 d左右,开花期株高75.7~105.3cm,成熟期株高98.5~133.8 cm.2年生干草产量为11739.14 kg·hm-2,比对照龙牧803苜蓿(9797.99 kg·hm-1)增产17.10%;种子产量284.60 kg·hm-2,比对照(230.00 kg·hm-2)增产18.25%.初花期粗蛋白含量19.38%,适口性好,饲用品质优良.其抗性强,生态适应性广,适宜在黑龙江省各地及毗邻省区推广种植.

  8. Up-regulation of heme oxygenase-1 contributes to the amelioration of aluminum-induced oxidative stress in Medicago sativa.

    Science.gov (United States)

    Cui, Weiti; Zhang, Jing; Xuan, Wei; Xie, Yanjie

    2013-10-15

    In this report, pharmacological, histochemical and molecular approaches were used to investigate the effect of heme oxygenase-1 (HO-1) up-regulation on the alleviation of aluminum (Al)-induced oxidative stress in Medicago sativa. Exposure of alfalfa to AlCl3 (0-100 μM) resulted in a dose-dependent inhibition of root elongation as well as the enhancement of thiobarbituric acid reactive substances (TBARS) content. 1 and 10 μM (in particular) Al(3+) increased alfalfa HO-1 transcript or its protein level, and HO activity in comparison with the decreased changes in 100 μM Al-treated samples. After recuperation, however, TBARS levels in 1 and 10 μM Al-treated alfalfa roots returned to control values, which were accompanied with the higher levels of HO activity. Subsequently, exogenous CO, a byproduct of HO-1, could substitute for the cytoprotective effects of the up-regulation of HO-1 in alfalfa plants upon Al stress, which was confirmed by the alleviation of TBARS and Al accumulation, as well as the histochemical analysis of lipid peroxidation and loss of plasma membrane integrity. Theses results indicated that endogenous CO generated via heme degradation by HO-1 could contribute in a critical manner to its protective effects. Additionally, the pretreatments of butylated hydroxytoluene (BHT) and hemin, an inducer of HO-1, exhibited the similar cytoprotective roles in the alleviation of oxidative stress, both of which were impaired by the potent inhibitor of HO-1, zinc protoporphyrin IX (ZnPP). However, the Al-induced inhibition of root elongation was not influenced by CO, BHT and hemin, respectively. Together, the present results showed up-regulation of HO-1 expression could act as a mechanism of cell protection against oxidative stress induced by Al treatment.

  9. Ectopic expression of GsPPCK3 and SCMRP in Medicago sativa enhances plant alkaline stress tolerance and methionine content.

    Science.gov (United States)

    Sun, Mingzhe; Sun, Xiaoli; Zhao, Yang; Zhao, Chaoyue; Duanmu, Huizi; Yu, Yang; Ji, Wei; Zhu, Yanming

    2014-01-01

    So far, it has been suggested that phosphoenolpyruvate carboxylases (PEPCs) and PEPC kinases (PPCKs) fulfill several important non-photosynthetic functions. However, the biological functions of soybean PPCKs, especially in alkali stress response, are not yet well known. In previous studies, we constructed a Glycine soja transcriptional profile, and identified three PPCK genes (GsPPCK1, GsPPCK2 and GsPPCK3) as potential alkali stress responsive genes. In this study, we confirmed the induced expression of GsPPCK3 under alkali stress and investigated its tissue expression specificity by using quantitative real-time PCR analysis. Then we ectopically expressed GsPPCK3 in Medicago sativa and found that GsPPCK3 overexpression improved plant alkali tolerance, as evidenced by lower levels of relative ion leakage and MDA content and higher levels of chlorophyll content and root activity. In this respect, we further co-transformed the GsPPCK3 and SCMRP genes into alfalfa, and demonstrated the increased alkali tolerance of GsPPCK3-SCMRP transgenic lines. Further investigation revealed that GsPPCK3-SCMRP co-overexpression promoted the PEPC activity, net photosynthetic rate and citric acid content of transgenic alfalfa under alkali stress. Moreover, we also observed the up-regulated expression of PEPC, CS (citrate synthase), H(+)-ATPase and NADP-ME genes in GsPPCK3-SCMRP transgenic alfalfa under alkali stress. As expected, we demonstrated that GsPPCK3-SCMRP transgenic lines displayed higher methionine content than wild type alfalfa. Taken together, results presented in this study supported the positive role of GsPPCK3 in plant response to alkali stress, and provided an effective way to simultaneously improve plant alkaline tolerance and methionine content, at least in legume crops.

  10. Arbuscular mycorrhizal colonization alters subcellular distribution and chemical forms of cadmium in Medicago sativa L. and resists cadmium toxicity.

    Science.gov (United States)

    Wang, Yuanpeng; Huang, Jing; Gao, Yanzheng

    2012-01-01

    Some plants can tolerate and even detoxify soils contaminated with heavy metals. This detoxification ability may depend on what chemical forms of metals are taken up by plants and how the plants distribute the toxins in their tissues. This, in turn, may have an important impact on phytoremediation. We investigated the impact of arbuscular mycorrhizal (AM) fungus, Glomus intraradices, on the subcellular distribution and chemical forms of cadmium (Cd) in alfalfa (Medicago sativa L.) that were grown in Cd-added soils. The fungus significantly colonized alfalfa roots by day 25 after planting. Colonization of alfalfa by G. intraradices in soils contaminated with Cd ranged from 17% to 69% after 25-60 days and then decreased to 43%. The biomass of plant shoots with AM fungi showed significant 1.7-fold increases compared to no AM fungi addition under the treatment of 20 mg kg(-1) Cd. Concentrations of Cd in the shoots of alfalfa under 0.5, 5, and 20 mgkg(-1) Cd without AM fungal inoculation are 1.87, 2.92, and 2.38 times higher, respectively, than those of fungi-inoculated plants. Fungal inoculation increased Cd (37.2-80.5%) in the cell walls of roots and shoots and decreased in membranes after 80 days of incubation compared to untreated plants. The proportion of the inactive forms of Cd in roots was higher in fungi-treated plants than in controls. Furthermore, although fungi-treated plants had less overall Cd in subcellular fragments in shoots, they had more inactive Cd in shoots than did control plants. These results provide a basis for further research on plant-microbe symbioses in soils contaminated with heavy metals, which may potentially help us develop management regimes for phytoremediation.

  11. Ectopic expression of GsPPCK3 and SCMRP in Medicago sativa enhances plant alkaline stress tolerance and methionine content.

    Directory of Open Access Journals (Sweden)

    Mingzhe Sun

    Full Text Available So far, it has been suggested that phosphoenolpyruvate carboxylases (PEPCs and PEPC kinases (PPCKs fulfill several important non-photosynthetic functions. However, the biological functions of soybean PPCKs, especially in alkali stress response, are not yet well known. In previous studies, we constructed a Glycine soja transcriptional profile, and identified three PPCK genes (GsPPCK1, GsPPCK2 and GsPPCK3 as potential alkali stress responsive genes. In this study, we confirmed the induced expression of GsPPCK3 under alkali stress and investigated its tissue expression specificity by using quantitative real-time PCR analysis. Then we ectopically expressed GsPPCK3 in Medicago sativa and found that GsPPCK3 overexpression improved plant alkali tolerance, as evidenced by lower levels of relative ion leakage and MDA content and higher levels of chlorophyll content and root activity. In this respect, we further co-transformed the GsPPCK3 and SCMRP genes into alfalfa, and demonstrated the increased alkali tolerance of GsPPCK3-SCMRP transgenic lines. Further investigation revealed that GsPPCK3-SCMRP co-overexpression promoted the PEPC activity, net photosynthetic rate and citric acid content of transgenic alfalfa under alkali stress. Moreover, we also observed the up-regulated expression of PEPC, CS (citrate synthase, H(+-ATPase and NADP-ME genes in GsPPCK3-SCMRP transgenic alfalfa under alkali stress. As expected, we demonstrated that GsPPCK3-SCMRP transgenic lines displayed higher methionine content than wild type alfalfa. Taken together, results presented in this study supported the positive role of GsPPCK3 in plant response to alkali stress, and provided an effective way to simultaneously improve plant alkaline tolerance and methionine content, at least in legume crops.

  12. Arbuscular mycorrhizal colonization alters subcellular distribution and chemical forms of cadmium in Medicago sativa L. and resists cadmium toxicity.

    Directory of Open Access Journals (Sweden)

    Yuanpeng Wang

    Full Text Available Some plants can tolerate and even detoxify soils contaminated with heavy metals. This detoxification ability may depend on what chemical forms of metals are taken up by plants and how the plants distribute the toxins in their tissues. This, in turn, may have an important impact on phytoremediation. We investigated the impact of arbuscular mycorrhizal (AM fungus, Glomus intraradices, on the subcellular distribution and chemical forms of cadmium (Cd in alfalfa (Medicago sativa L. that were grown in Cd-added soils. The fungus significantly colonized alfalfa roots by day 25 after planting. Colonization of alfalfa by G. intraradices in soils contaminated with Cd ranged from 17% to 69% after 25-60 days and then decreased to 43%. The biomass of plant shoots with AM fungi showed significant 1.7-fold increases compared to no AM fungi addition under the treatment of 20 mg kg(-1 Cd. Concentrations of Cd in the shoots of alfalfa under 0.5, 5, and 20 mgkg(-1 Cd without AM fungal inoculation are 1.87, 2.92, and 2.38 times higher, respectively, than those of fungi-inoculated plants. Fungal inoculation increased Cd (37.2-80.5% in the cell walls of roots and shoots and decreased in membranes after 80 days of incubation compared to untreated plants. The proportion of the inactive forms of Cd in roots was higher in fungi-treated plants than in controls. Furthermore, although fungi-treated plants had less overall Cd in subcellular fragments in shoots, they had more inactive Cd in shoots than did control plants. These results provide a basis for further research on plant-microbe symbioses in soils contaminated with heavy metals, which may potentially help us develop management regimes for phytoremediation.

  13. Broadening the U.S. alfalfa germplasm base

    Science.gov (United States)

    Over 4000 alfalfa (Medicago sativa L.) plant introductions (PIs) exist in the USDA-ARS National Plant Germplasm System (NPGS). NAAIC has discussed/proposed pre-breeding efforts to utilize this germplasm for creating pre-commercial alfalfa germplasm. Funding constraints have been one impediment to th...

  14. Complete genome sequence of the alfalfa latent virus

    Science.gov (United States)

    Alfalfa latent virus (ALV) is a member of the carlavirus group and occurs symptomlessly in alfalfa (Medicago sativa). In the US it is prevalent in Nebraska and Wisconsin. The virus is recognized as a strain of Pea streak virus (PeSV) So far, no complete genomic sequence of PSV or ALV is availab...

  15. Biological nitrogen fixation by lucerne (Medicago sativa L.) in acid soils.

    NARCIS (Netherlands)

    Pijnenborg, J.W.M.

    1990-01-01

    Growth of lucerne( Medicago sativa L.) is poor in soils with values of pH-H2O below 6. This is often due to nitrogen deficiency, resulting from a hampered performance of the symbiosis withRhizobium meliloti. This thesis deals with the factors affecting biological nitrogen fixat

  16. Lucerne (Medicago sativa) or grass-clover as cut-and-carry fertilizers in organic agriculture

    NARCIS (Netherlands)

    Burgt, van der G.J.H.M.; Eekeren, van N.J.M.; Scholberg, J.M.S.; Koopmans, C.J.

    2013-01-01

    Onfarm nitrogen fixation is a driving force in organic agriculture. The efficiency with which this nitrogen is used can be increased by using lucerne (Medicago sativa) or grassclover directly as sources of fertilizer on arable land: cutandcarry fertilizers. In two arable crops, the use of lucerne an

  17. Exogenous Hematin Alleviates Mercury-induced Oxidative Damage in the Roots of Medicago sativa

    Institute of Scientific and Technical Information of China (English)

    Yi Han; Wei Xuan; Tian Yu; Wen-Bing Fang; Tian-Ling Lou; Yin Gao; Xiao-Yue Chen; Xiao Xiao; Wen-Biao Shen

    2007-01-01

    In the present study, we evaluated the protective effect of exogenous heme oxygenase-1 (HO-1 EC1.14.99.3) inducer hematin against mercury-induced oxidative damage in the roots of Alfalfa (Medicago sativa L.).Plants exposed to mercury (HgCl2) exhibited a significant increase of lipid peroxidation, as well as inhibition of root elongation.However, hematin (50 μM)supplementation to HgCl2 (100 μmol/L) treated plants effectively reduced the lipid peroxidation and partially increased the root elongation.These responses were mimicked by the application of aqueous solution of carbon monoxide (CO) with 50% saturation.Also, treatment with hematin could result in the potent induction of HO-1 transcript in the root tissues,as detected 12h following treatment.Moreover, the activation of anti-oxidant enzyme, including glutathione reductase,monodehydroascorbate reductase and superoxide dismutase activities, and the decrease of lipoxygenase activity, were induced by hematin at 12h or 24h, which was further confirmed by histochemical staining for the detection of lipid peroxidation and loss of membrane integrity.Whereas, ascorbate peroxidase and guaiacol peroxidase isozyme activities or their transcripts were reduced, respectively, indicating that hydrogen peroxide might act as a signal to mediate Hg-tolerance at the beginning of treatment.The ameliorating effects of hematin were specific, since the CO scavenger hemoglobin differentially reversed the above actions.Taken together, our results suggested that hematin exhibits a vital role in protecting the plant against Hg-induced oxidative damage.

  18. ECOLOGICAL RISK ASSESSMENT OF ALFALFA (MEDICAGO VARIA L.) GENETICLALY ENGINEERED TO EXPRESS A HUMAN METALLOTHIONEIN (HMT) GENE

    Science.gov (United States)

    The objectives of these studies were two-fold: (1) to determine efficacy of low and high expression hMT gene constructs by assessing accumulation of Cu in shoots of parental and transgenic plants of alfalfa (Medicago varia L.) exposed to different concentrations of CuSO4 by addit...

  19. Effects of salinity and drought stress on germination, biomass and growth in three varieties of Medicago sativa L.

    Directory of Open Access Journals (Sweden)

    A. Castroluna

    2014-01-01

    Full Text Available En plántulas de alfalfa (Medicago sativa L. se evaluó la germinación y el crecimiento y su tolerancia al estrés osmótico inducido por Polietilenglicol 6000 (PEG6000 y salinidad (NaCl en tres genotipos distintos: Dk166, Verdor y Salina. Esta investigación se llevó a cabo con un diseño experimental completamente aleatorizado, con cinco réplicas y los parámetros que se determinaron fueron: energía y poder germinativo, largo de hojas y peso fresco y peso seco de raíces y hojas. Los resultados mostraron que la germinación fue retrasada en todas las variedades con ambas soluciones, con diferencias entre genotipos. El crecimiento de las plántulas, bajo un ligero estrés mostraron un incremento de la biomasa aérea y en un estrés hídrico y salino severo, muerte de las plantas excepto en Var. Salina (tolerante. PEG causó muerte en la variedad Verdor que mostró más sensibilidad a PEG que a NaCl. En raíces, los genotipos más sensibles frente a leves estrés salinos detuvieron su crecimiento y bajo leves situaciones de estrés hídrico lo incrementaron. Nuestros estudios nos permiten definir las variedades comerciales de Medicago sativa como moderadamente tolerantes a salinidad y sequía la variedad DK166, sensible o intolerante a salinidad y sequía la variedad Verdor y con una alta tolerancia a salinidad e insensible a sequía la variedad Salina.

  20. La simbiosis fijadora de nitrógeno Sinorhizobium meliloti-alfalfa: aproximaciones ómicas aplicadas a la identificación y caracterización de determinantes genéticos del rizobio asociados a la colonización temprana de la raíz de alfalfa (Medicago sativa)

    OpenAIRE

    Salas, María Eugenia

    2015-01-01

    Sinorhizobium meliloti es una α-proteobacteria capaz de establecer asociaciones simbióticas con plantas de los géneros Medicago, Melilotus y Trigonella. Esta asociación es el resultado de un complejo diálogo molecular entre los simbiontes, que se diferencian a lo largo de la interacción para dar lugar a un nuevo órgano en las raíces de las plantas, el nódulo fijador de nitrógeno. El nicho simbiótico accesible a los rizobios está naturalmente limitado, y resulta ocupado por aquellas cepas que ...

  1. Isolation, chemical characterization and biological activity of alfalfa (Medicago media Pers. root saponins

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    Wiesław Oleszek

    2014-01-01

    Full Text Available Saponins from alfalfa (Medicago media Pers. roots were isolated and their acid hydrolysis revealed several aglycones that were obtained in crystalline form and characterized. Medicagenic acid, hederagenin and soyasapogenols A. B, C. D, E and F were found. Crude saponins were separated into cholesterol-precipitable and nonprecipitable fractions. The precipitable fraction consisted of medicagenic acid glycosides: glucose, arabinose, xylose and rhamnose were found as their sugar chain components. The nonprecipitable fraction was a mixture of hederagenine and soyasapogenol glycosides, and glucose arthinose. xylose. galactose and glucuronic acid were found in the sugar component,. 7 he medicagenic acid glycosides made up 6% of root dry matter and showed high biological activity. They cuased red blood cells lysis (haemolytic index 3000, completely inhibited Trichoderma viride growth at the concentration of 2.5 Mg. 100 cm-3 of growth medium and retarded wheat seedling growth at concentrations as low as 100 ppm. The cholesterol-nonprecipitable fraction caused no blood cell lysis and fungus growth inhibition, although it did inhibit seedling growth, but to a much lesser extent than medicagenic acrd glycosides. The detrimental effect of alfalfa root saponins on winter wheat crop after alfalfa is discussed.

  2. Accumulation of heavy metals in Medicago sativa L. and Trifolium pratense L. at the contaminated fluvisol

    Directory of Open Access Journals (Sweden)

    Jakšić Snežana P.

    2013-01-01

    Full Text Available Recently, heavy metals concentrations increased in some agricultural areas due to the consequences of anthropogenic impacts. The aim of this study was to determine the level of heavy metals (As, Cr, Ni and Pb in Medicago sativa L. and Trifolium pratense L. grown on fluvisol, in order to obtain information on safety of these nutrients. The total content of Pb, As, Cr and Ni in the samples of fluvisol was above the maximum allowable amount. The content of heavy metals in Medicago sativa L. and Trifolium pratense L. was below the critical and toxic concentrations in all samples originating from contaminated soil. It was concluded that the accumulation of heavy metals in plants did not depend only on the total content in soil, but also the affinity of the plant, and individual and interactive effects of various soil properties. No statistically significant differences in the accumulation of heavy metals between Medicago sativa L. and Trifolium pratense L were observed. It is necessary to further control of heavy metals in the investigated area, in order to prevent their entry into the food chain and provide healthy food.

  3. Molecular cloning of a bifunctional beta-xylosidase/alpha-L-arabinosidase from alfalfa roots: heterologous expression in Medicago truncatula and substrate specificity of the purified enzyme.

    Science.gov (United States)

    Xiong, Jin-Song; Balland-Vanney, Maud; Xie, Zhi-Ping; Schultze, Michael; Kondorosi, Adam; Kondorosi, Eva; Staehelin, Christian

    2007-01-01

    Glycoside hydrolases are often members of a multigene family, suggesting individual roles for each isoenzyme. Various extracellular glycoside hydrolases have an important but poorly understood function in remodelling the cell wall during plant growth. Here, MsXyl1, a concanavalin A-binding protein from alfalfa (Medicago sativa L.) belonging to the glycoside hydrolase family 3 (beta-D-xylosidase branch) is characterized. Transcripts of MsXyl1 were detected in roots (particularly root tips), root nodules, and flowers. MsXyl1 under the control of the CaMV 35S promoter was expressed in the model legume Medicago truncatula (Gaertner). Concanavalin A-binding proteins from the transgenic plants exhibited 5-8-fold increased activities towards three p-nitrophenyl (PNP) glycosides, namely PNP-beta-D-xyloside, PNP-alpha-L-arabinofuranoside, and PNP-alpha-L-arabinopyranoside. An antiserum raised against a synthetic peptide recognized MsXyl1, which was processed to a 65 kDa form. To characterize the substrate specificity of MsXyl1, the recombinant protein was purified from transgenic M. truncatula leaves by concanavalin A and anion chromatography. MsXyl1cleaved beta-1,4-linked D-xylo-oligosaccharides and alpha-1,5-linked L-arabino-oligosaccharides. Arabinoxylan (from wheat) and arabinan (from sugar beet) were substrates for MsXyl1, whereas xylan (from oat spelts) was resistant to degradation. Furthermore, MsXyl1 released xylose and arabinose from cell wall polysaccharides isolated from alfalfa roots. These data suggest that MsXyl1 is a multifunctional beta-xylosidase/alpha-L-arabinofuranosidase/alpha-L-arabinopyranosidase implicated in cell wall turnover of arabinose and xylose, particularly in rapidly growing root tips. Moreover, the findings of this study demonstrate that stable transgenic M. truncatula plants serve as an excellent expression system for purification and characterization of proteins.

  4. Alfalfa interseeded into silage corn can serve as a cover crop and subsequent forage crop

    Science.gov (United States)

    Alfalfa (Medicago sativa) and corn (Zea mays) silage are commonly grown in rotation in dairy forage production systems throughout the northern regions of the USA. Alfalfa interseeded into silage corn could potentially serve two purposes: as a cover crop during the silage corn production year, and as...

  5. Selfing rate in an alfalfa seed production field pollinated with leafcutter bees

    Science.gov (United States)

    Self-pollination or “selfing” in autotetraploid alfalfa (Medicago sativa L.) (2n = 4x = 32) leads to severe inbreeding depression. Investigating selfing in alfalfa seed production may allow mitigation strategy development against potential negative impacts of selfing on varietal performance. Using m...

  6. Mechanisms of qualitative and quantitative resistance to Aphanomyces root rot in alfalfa

    Science.gov (United States)

    Aphanomyces root rot (ARR), caused by Aphanomyces euteiches, is one of the most important diseases of alfalfa (Medicago sativa) in the United States. Two races of the pathogen are currently recognized. Most modern alfalfa cultivars have high levels of resistance to race 1 but few cultivars have resi...

  7. Prohexadione-calcium improves stand density and yield of alfalfa interseeded into silage corn

    Science.gov (United States)

    Interseeded alfalfa (Medicago sativa L.) could serve as a dual-purpose crop to provide groundcover for silage corn (Zea mays L.) and forage during subsequent years of production, but interspecific competition often leads to poor stands of alfalfa and unsatisfactory yields of corn. Four experiments e...

  8. P-HYDROXYPHENYLPYRUVATE DIOXYGENASE from Medicago sativa is involved in vitamin E biosynthesis and abscisic acid-mediated seed germination

    Science.gov (United States)

    Jiang, Jishan; Chen, Zhihong; Ban, Liping; Wu, Yudi; Huang, Jianping; Chu, Jinfang; Fang, Shuang; Wang, Zan; Gao, Hongwen; Wang, Xuemin

    2017-01-01

    P-HYDROXYPHENYLPYRUVATE DIOXYGENASE (HPPD) is the first committed enzyme involved in the biosynthesis of vitamin E, and is characterized by catalyzing the conversion of p-hydroxyphenyl pyruvate (HPP) to homogentisic acid (HGA). Here, an HPPD gene was cloned from Medicago sativa L. and designated MsHPPD, which was expressed at high levels in alfalfa leaves. PEG 6000 (polyethylene glycol), NaCl, abscisic acid and salicylic acid were shown to significantly induce MsHPPD expression, especially in the cotyledons and root tissues. Overexpression of MsHPPD was found to significantly increase the level of β-tocotrienol and the total vitamin E content in Arabidopsis seeds. Furthermore, these transgenic Arabidopsis seeds exhibited an accelerated germination time, compared with wild-type seeds under normal conditions, as well as under NaCl and ABA treatments. Meanwhile, the expression level of several genes associated with ABA biosynthesis (NCED3, NCED5 and NCED9) and the ABA signaling pathway (RAB18, ABI3 and ABI5) were significantly down-regulated in MsHPPD-overexpressing transgenic lines, as well as the total free ABA content. Taken together, these results demonstrate that MsHPPD functions not only in the vitamin E biosynthetic pathway, but also plays a critical role in seed germination via affecting ABA biosynthesis and signaling. PMID:28084442

  9. Characterization of the plant growth promoting bacterium, Enterobacter cloacae MSR1, isolated from roots of non-nodulating Medicago sativa.

    Science.gov (United States)

    Khalifa, Ashraf Y Z; Alsyeeh, Abdel-Moneium; Almalki, Mohammed A; Saleh, Farag A

    2016-01-01

    The aim of the present study was to characterize the endophytic bacterial strain designated MSR1 that was isolated from inside the non-nodulating roots of Medicago sativa after surface-sterilization. MSR1 was identified as Enterobacter cloacae using both 16S rDNA gene sequence analysis and API20E biochemical identification system (Biomerieux, France). Furthermore, this bacterium was characterized using API50CH kit (Biomerieux, France) and tested for antibacterial activities against some food borne pathogens. The results showed that E. cloacae consumed certain carbohydrates such as glycerol, d-xylose, d-maltose and esculin melibiose as a sole carbon source and certain amino acids such as arginine, tryptophan ornithine as nitrogen source. Furthermore, MSR1 possessed multiple plant-growth promoting characteristics; phosphate solubility, production of phytohormones acetoin and bioactive compounds. Inoculation of Pisum sativum with MSR1 significantly improved the growth parameters (the length and dry weight) of this economically important grain legume compared to the non-treated plants. To our knowledge, this is the first report addressing E. cloacae which exist in roots of alfalfa growing in Al-Ahsaa region. The results confirmed that E. cloacae exhibited traits for plant growth promoting and could be developed as an eco-friendly biofertilizer for P. sativum and probably for other important plant species in future.

  10. A PROPOSITO DE UN ENSAYO CON ABONOS (cal y harina de huesos EN ALFALFAl (Medicago sativai

    Directory of Open Access Journals (Sweden)

    Isidoro Mogilner

    2010-11-01

    Full Text Available

    En este trabajo, los autores estudian el efecto que sobre el rendimiento de la alfalfa (Medicago sativa produce la incorporación de diferentes dosis de cal y harina de huesos, en un suelo pobre de P y Ca; de una textura pesada con alto contenido de arcilla en todos los horizontes, de un pH ácido (5.1 a 6.2 y que es característico de la zona donde fué hecha la experiencia.
    Se han obtenido resultados referentes a la influencia de la inoculación de la semilla con Rhizobium y el agregado de cal y harina de huesos sobre los rendimientos.

  11. [MEDICAGO SATIVA L: IMPROVEMENT AND NEW APPROACHES OF ITS NUTRITIONAL AND FUNCTIONAL VALUE BY BACTERIAL CO-INOCULATION].

    Science.gov (United States)

    Martínez, Rosario; Nebot, Elena; Porres, Jesús María; Kapravelou, Garyfallia; Del Moral, Ana; Talbi, Chouhra; Bedmar, Eulogio Jose; López-Jurado, María

    2015-12-01

    Objetivo: estudiar el efecto de la inoculación con Ensifer meliloti y Halomonas maura sobre el crecimiento y el valor nutricional y funcional de la leguminosa Medicago sativa L., cultivada bajo condiciones de salinidad. Método: las plantas de M. sativa se cultivaron con una solución de mezcla de sales CaSO4, MgCl, NaCl and Na- HCO3 y se coinocularon con su rizobio específico y la bacteria H. maura. Se determinaron los parámetros fisiológicos de las plantas, así como el contenido en nitrógeno y minerales, y se llevó a cabo un proceso de digestibilidad in vitro. Resultados: la salinidad ejerció un efecto negativo sobre las plantas; sin embargo, la coinoculación de las mismas incrementó su productividad, el contenido en nitrógeno, minerales totales, Ca y Mg. Además, los parámetros fisiológicos de potencial hídrico y concentración de leghemoglobina se incrementaron. Tanto la salinidad como la coinoculación de las plantas aumentaron la capacidad antioxidante de la leguminosa en los dializados y retenidos obtenidos tras someter a la planta a un proceso de digestibilidad in vitro. Conclusión: la coinoculación con E. meliloti y H. maura podría mejorar el cultivo de la alfalfa bajo condiciones específicas de salinidad, aumentando su composición nutricional y funcional, pudiendo considerarse en la formulación de suplementos nutricionales para el consumo humano.

  12. [Responses of Medicago sativa and Astragalus adsurgens seedlings growth and water use to soil moisture regime].

    Science.gov (United States)

    Xu, Bingcheng; Shan, Lun; Li, Fengmin

    2005-12-01

    In the semi-arid area of Loess Plateau, seasonal drought often occurs during the vegetative stage of grass plants, leading to the subsequent serious reduction of their yield. Aimed to study the responses of the seedlings growth and water use of two perennial leguminous grasses Medicago sativa and Astragalus adsurgens to different soil moisture regimes, a pot experiment was installed with five treatments, i.e., adequate water supply (HW), moderate water stress (LW), soil drying gradually from HW (DHW) and LW (DLW), and refilling water to LW after soil drying from LW (RWL). The results showed that under HW, the seedlings of both M. sativa and A. adsurgens had the highest biomass and transpiration water use efficiency (TWUE), and M. sativa had a significantly higher biomass than A. adsurgens (P < 0.05). When the soil moisture content declined, M. sativa had a higher reduction rate in biomass and TWUE than A. adsurgens, and after the soil moisture regime changed from LW and DLW to RWL, the biomass of M. sativa and A. adsurgens was reduced by 47.8% and 27.9%, respectively, as compared to LW (P < 0.05). At the same time, the root/shoot ratio (R/S) of M. sativa and its water consumption per unit root increased significantly, while the TWUE decreased significantly (P < 0.05); but for A. adsurgens, its R/S decreased significantly (P < 0.05), while the TWUE and the water consumption per unit root had no significant change.

  13. Research Progress on Mixed Silage of Medicago sativa%紫花苜蓿混合青贮研究进展

    Institute of Scientific and Technical Information of China (English)

    葛剑; 刘贵河; 杨翠军; 白雪梅; 孔伟

    2014-01-01

    紫花苜蓿单独青贮品质不佳,混合青贮能够提高原料糖分含量,增加乳酸菌数量或抑制不良发酵,进而提高青贮发酵品质和养分含量。阐述了紫花苜蓿与禾本科牧草、谷物秸秆等进行混合青贮的研究现状,对乳酸菌、绿汁发酵液、纤维素酶、甲酸、蔗糖等添加剂在苜蓿青贮中的应用效果进行了概述,并探讨了抑制苜蓿青贮蛋白质降解的新技术手段,为调制优质苜蓿青贮饲料提供参考。%The quality of Medicago sativa silage alone was poor,but mixed silage could improve sugar content of raw material and increase the amount of lactic acid bacteria,and furthermore improve the fermentation quality and nutrients content.This paper described the research status of mixed silage of Medicago sativa and gramineous forage or corn straw,and summarized the application effects of silage additives of lactic acid bacteria,previously fermented j uices,cellulytic enzymes,formic acid and sucrose,etc.At last,new technology of inhibiting protein degradation of alfalfa silage was explored,so as to provide reference to modulation quality of alfalfa silage.

  14. Photosynthesis rate in response to light intensity and CO2 concentration in different alfalfa varieties%不同苜蓿(Medicago sativa L.)品种光合速率对光和CO2浓度的响应特征

    Institute of Scientific and Technical Information of China (English)

    董志新; 韩清芳; 贾志宽; 任广鑫

    2007-01-01

    以6个紫花苜蓿(Medicago sativa L.)品种为对象,用Licor-6400 型便携式光合作用测定系统测定了紫花苜蓿光合作用对光、CO2的响应曲线,阐述了光合作用对光和CO2浓度的响应特征.结果表明,各品种光合速率随光强或CO2浓度的提高而增大均可用指数方程来模拟,并得出一些光合响应特征参数:表观量子效率、羧化效率、光补偿点、近光饱和点、暗呼吸速率、光呼吸速率、CO2补偿点、CO2饱和点等,品种间差异显著;巨人201+Z、路宝具较高的近光饱和点、表观量子效率及羧化效率,较低的CO2补偿点,是具有较高的光能生产潜力的苜蓿品种;秋眠级数与表观量子效率、羧化效率、光补偿点、近光饱和点、暗呼吸速率、光呼吸速率均成不同程度的负相关,与CO2补偿点、CO2饱和点成微弱正相关,均未达到显著水平.

  15. Natural occurrence of entomophthoroid fungi of aphid pests on Medicago sativa L. in Argentina.

    Science.gov (United States)

    Manfrino, Romina G; Zumoffen, Leticia; Salto, César E; Lastra, Claudia C López

    2014-01-01

    Four species of entomophthoroid fungi, Pandora neoaphidis (Entomophthorales: Entomophthoraceae), Zoophthora radicans (Entomophthorales: Entomophthoraceae), Entomophthora planchoniana (Entomophthorales: Entomophthoraceae) and Neozygites fresenii (Neozygitales: Neozygitaceae) were found to infect Aphis craccivora, Therioaphis trifolii, and Acyrthosiphon pisum and unidentified species of Acyrthosiphon on lucerne in Argentina. Samples were collected from five sites (Ceres, Rafaela, Sarmiento, Monte Vera and Bernardo de Irigoyen) in the province of Santa Fe. In this study, Zoophthora radicans was the most important pathogen and was recorded mainly on Acyrthosiphon sp. Zoophthora radicans was successfully isolated and maintained in pure cultures. This study is the first report of entomophthoroid fungi infecting lucerne (Medicago sativa L.) aphids in Argentina.

  16. Effect of salt stress on germination and enzyme activity in two genotypes of Medicago sativa

    OpenAIRE

    Ilyess Lachhab; Said Louahlia; Meryem Laamarti; Khalil Hammani

    2013-01-01

    The arid and semi-arid represent one third of the earth's surface. In these areas, soil salinity and irrigation water is one of the limiting factors for plant productivity and crop yields. These ecosystems are characterized by a high variability of rainfall combined with high evaporation favoring the accumulation of salts in the soil. This affects about 7% of the total area in the world. Germination of Medicago sativa is inhibited by 1.5% NaCl (260 mmol/l). Sodium chloride (NaCl) salinity is ...

  17. Biogenic Pt uptake and nanoparticle formation in Medicago sativa and Brassica juncea

    Science.gov (United States)

    Bali, Roza; Siegele, Rainer; Harris, Andrew T.

    2010-10-01

    The ability of the facultative metallophyte plants, Medicago sativa ( M. sativa) and Brassica juncea ( B. juncea) to accumulate and translocate platinum (Pt) from aqueous substrates is reported. The influence of Pt concentration in the substrate (5, 10, 20, 40 and 80 ppm), exposure time (24, 48 and 72 h) and substrate pH (2, 3, 5, 7 and 9) was determined. In both plants the concentration of Pt increased with substrate concentration and exposure time. Greater accumulation was detected in the roots of M. sativa than B. juncea, up to a maximum of 94.19 mg Pt g-1 (dry biomass) compared with 38.5 mg Pt g-1 (dry biomass) following exposure to 80 ppm Pt after 72 h exposure, respectively. However, at lower substrate concentrations (5 and 20 ppm) greater quantities of Pt were detected in the shoots of B. juncea, ranging between 0.02 and 0.32 mg Pt g-1 (dry biomass) at 5 ppm across the different time intervals studied, compared with 0.02-0.14 mg Pt g-1 (dry biomass) for M. sativa, suggesting B. juncea to be a better translocator of Pt under idealised conditions at low concentrations. Higher Pt uptake was also observed in acidic media, with a maximum at pH 2 for M. sativa and pH 3 for B. juncea, indicating the role of net surface charge on the bioaccumulation of Pt. Once sequestered Pt(II) was reduced to Pt(0) due to the action of local metabolites. TEM images of M. sativa root samples showed the in vivo formation of Pt nanoparticles between 3 and 100 nm in size and of varying morphologies in the epidermal root cells. In vivo Pt distribution profiles were assessed using proton induced X-ray emission (μ-PIXE) spectroscopy, which showed even distribution across all tissue systems (epidermal, cortical and vascular) within the roots of both M. sativa and B. juncea.

  18. Alfalfa

    Science.gov (United States)

    Alfalfa is an herb. People use the leaves, sprouts, and seeds to make medicine. Alfalfa is used for kidney conditions, bladder and prostate ... bleeding disorder called thrombocytopenic purpura. People also take alfalfa as a source of vitamins A, C, E, ...

  19. Application of Biotechnology in the Improvement of Stress Tolerance in Medicago sativa L.%生物技术在紫花苜蓿抗逆改良上的应用

    Institute of Scientific and Technical Information of China (English)

    凌虹; 胡艳; 玉永雄

    2012-01-01

    Alfalfa (Medicago sativa L. ) is high-quality legume forage in the world. To breed new cultivars of stress-tolerant M. sativa is of great significance to improving the M. sativa yield and promoting the industrialization of M. sativa production. Biotechnology is a new technology which develops very fast in recent years. In this paper, the progresses of tolerance to biotic and abiotic stresses in M. sativa by genetic transformation were reviewed, and the application of biotechnology in the improvement of stress tolerance in M. sativa was forecasted.%紫花苜蓿是世界上优良的豆科牧草,培育抗逆苜蓿新品种对于提高苜蓿产量和推动苜蓿产业化具有重要意义.近年来,生物技术是世界上发展最迅速的新技术,该研究综述了紫花苜蓿抗生物胁迫和抗非生物胁迫遗传转化方面的研究进展,并对生物技术在苜蓿抗逆性状改良上的应用进行了展望.

  20. Phenanthrene uptake by Medicago sativa L. under the influence of an arbuscular mycorrhizal fungus

    Energy Technology Data Exchange (ETDEWEB)

    Wu Naiying [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, PO Box 2871, Beijing 100085 (China); Department of Chemistry, Shangqiu Normal College, Shangqiu 476000 (China); Huang Honglin [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, PO Box 2871, Beijing 100085 (China); Zhang Shuzhen, E-mail: szzhang@rcees.ac.c [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, PO Box 2871, Beijing 100085 (China); Zhu Yongguan [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, PO Box 2871, Beijing 100085 (China); Christie, Peter [Agri-Environment Branch, Agriculture Food and Environmental Science Division, Agri-Food and Biosciences Institute, Newforge Lane, Belfast BT9 5PX (United Kingdom); Zhang Yong [State Key Laboratory of Marine Environmental Science, Environmental Science Research Centre, Xiamen University, Xiamen 361005 (China)

    2009-05-15

    Phenanthrene uptake by Medicago sativa L. was investigated under the influence of an arbuscular mycorrhizal fungus. Inoculation of lucerne with the arbuscular mycorrhizal fungus Glomus etunicatum L. resulted in higher phenanthrene accumulation in the roots and lower accumulation in the shoots compared to non-mycorrhizal controls. Studies on sorption and desorption of phenanthrene by roots and characterization of heterogeneity of mycorrhizal and non-mycorrhizal roots using solid-state {sup 13}C nuclear magnetic resonance spectroscopy ({sup 13}C NMR) demonstrated that increased aromatic components due to mycorrhizal inoculation resulted in enhanced phenanthrene uptake by the roots but lower translocation to the shoots. Direct visualization using two-photon excitation microscopy (TPEM) revealed higher phenanthrene accumulation in epidermal cells of roots and lower transport into the root interior and stem in mycorrhizal plants than in non-mycorrhizal controls. These results provide some insight into the mechanisms by which arbuscular mycorrhizal inoculation may influence the uptake of organic contaminants by plants. - Colonization by an arbuscular mycorrhizal fungus promoted root uptake and decreased shoot uptake of phenanthrene by Medicago sativa L.

  1. Thiaminase activities and thiamine content of Pteridium aquilinum, Equisetum ramosissimum, Malva parviflora, Pennisetum clandestinum and Medicago sativa.

    Science.gov (United States)

    Meyer, P

    1989-06-01

    Thiaminase type 1 and 2 activities and thiamine content of five plants were determined. Of these Pteridium aquilinum and Equisetum ramosissimum were found to have considerably more thiaminase activity and lower thiamine content than Malva parviflora, Pennisetum clandestinum and Medicago sativa.

  2. Altered callose deposition during embryo sac formation of multi-pistil mutant (mp1) in Medicago sativa.

    Science.gov (United States)

    Zhou, H C; Jin, L; Li, J; Wang, X J

    2016-06-03

    Whether callose deposition is the cause or result of ovule sterility in Medicago sativa remains controversial, because it is unclear when and where changes in callose deposition and dissolution occur during fertile and sterile embryo sac formation. Here, alfalfa spontaneous multi-pistil mutant (mp1) and wild-type plants were used to compare the dynamics of callose deposition during embryo sac formation using microscopy. The results showed that both mutant and wild-type plants experienced megasporogenesis and megagametogenesis, and there was no significant difference during megasporogenesis. In contrast to the wild-type plants, in which the mature embryo sac was observed after three continuous cycles of mitosis, functional megaspores of mutant plants developed abnormally after the second round of mitosis, leading to degeneration of synergid, central, and antipodal cells. Callose deposition in both mutant and wild-type plants was first observed in the walls of megasporocytes, and then in the megaspore tetrad walls. After meiosis, the callose wall began to degrade as the functional megaspore underwent mitosis, and almost no callose was observed in the mature embryo sac in wild-type plants. However, callose deposition was observed in mp1 plants around the synergid, and increased with the development of the embryo sac, and was mainly deposited at the micropylar end. Our results indicate that synergid, central, and antipodal cells, which are surrounded by callose, may degrade owing to lack of nutrition. Callose accumulation around the synergid and at the micropylar end may hinder signals required for the pollen tube to enter the embryo sac, leading to abortion.

  3. Isolation and characterization of a gene from Medicago sativa L., encoding a bZIP transcription factor.

    Science.gov (United States)

    Li, Yan; Sun, Yan; Yang, Qingchuan; Fang, Feng; Kang, Junmei; Zhang, Tiejun

    2013-02-01

    A full-length cDNA of 1,537 nucleotides was cloned from Medicago sativa L. cv. "Zhongmu No. 1" by rapid amplification of cDNA ends. It was designated as MsZIP, encoding a protein of 340 amino acids. The protein molecular weight was 36.43 kDa, and the theoretical isoelectric point was 5.72. The MsZIP preferentially localized in nucleus and have signal peptide. Blast analysis revealed that MsZIP shared the highest homology with some bZIP proteins of M. truncatula. The transcript of MsZIP was strongly enriched in leaf compared with root and stem of mature alfalfa plants. MsZIP was strongly induced by 15 % PEG6000 (polyethylene glycol), 50 μM abscisic acid, 200 mM NaCl, 70 μM gibberellic acid, 5 mM salicylic acid and 200 μM methyl jasmonate. Physiological resistance parameters were measured in the transgenic tobacco. Malondialdehyde content, relative water content, soluble sugar content, soluble protein content and proline content in transgenic tobacco increased compared with non-transgenic tobacco under salt stress or drought stress. The results showed that accumulation of the MsZIP protein in the vegetative tissues of transgenic plants enhanced their tolerance to osmotic pressure stress. These results demonstrate a role for the MsZIP protein in stress protection and suggest the potential of the MsZIP gene for genetic engineering of salt tolerance and drought tolerance.

  4. Impacts on potential ethanol and crude protein yield in alfalfa

    Science.gov (United States)

    An alfalfa (Medicago sativa L.) biomass energy production system would produce two products. Leaves would be separated from stems to produce a high protein feed for livestock while stems would be processed to produce ethanol. Therefore, maximum yields of both leaves and stems are essential for profi...

  5. Evaluation of alfalfa-tall fescue mixtures across multiple environments

    Science.gov (United States)

    Binary grass-legume mixtures can benefit forage production systems in different ways helping growers cope both with increasing input costs (e.g., N fertilizer, herbicides) and potentially more variable weather. The main objective of this study was to evaluate alfalfa (Medicago sativa L.) and tall f...

  6. Paternity testing in an autotetraploid alfalfa breeding polycross

    Science.gov (United States)

    Determining unknown parentage in autotetraploid alfalfa (Medicago sativa L.) (2n = 4x = 32) can improve breeding gains. Exclusion analysis based paternity testing SAS code is presented, amenable to genotyping errors, for autotetraploid species utilizing co-dominant molecular markers with ambiguous d...

  7. Activity and multiple forms of peroxidase in Zea mays and Medicago sativa treated and non-treated with lead

    Energy Technology Data Exchange (ETDEWEB)

    Maier, R.

    1978-02-11

    The influence of lead on peroxidase was studied in young plants of Zee mays and Medicago sativa grown in solutions of Pb(NO/sub 3/)/sub 2/. The content of nitrate in the control- and the lead-solutions was equalized by NaNO/sub 3/. In the patterns of the multiple forms in roots and leaves of Zea and Medicago qualitatively no, or respectively negligible, change between control and lead-treated plants takes place. The temperature during the lead-treatment does not effect the numbers and the positions of bands. The bands' activity of peroxidase in lead-treated plants differs clearly from untreated plants, resulting in a different activity of the whole enzyme. In the roots and in the leaves of Zea as well as in the leaves of Medicago the relative activity of the peroxidase in lead-treated plants is raised. In the roots of Medicago the relative activity decreased slightly.

  8. EFFECT OF STORAGE TIME ON ALFALFA SEED QUALITY

    Directory of Open Access Journals (Sweden)

    Tihomir ČUPIĆ

    2005-07-01

    Full Text Available Alfalfa (Medicago sativa L. is a crop characterised by presence of hard (dormant seed that are viable but do not germinate in seed quality testing. In Republic of Croatia seed are frequently stored for three to four years due to low needs for seed of alfalfa and considerable import. The share of hard seed is decreased by storage time, temperature and air moisture changes and therefore directly keeps the level of seed germination in a longer period of storage.

  9. Identification and Preliminary Analysis of Salt Stress-responsive Genes in Leaves of Southern Type Alfalfa (Medicago sativa ‘Millennium’)%南方型紫花苜蓿叶片盐胁迫应答基因鉴定与分析

    Institute of Scientific and Technical Information of China (English)

    马进; 郑钢

    2015-01-01

    以南方型紫花苜蓿(Medicago sativa ‘Millennium’)为材料,以正常培养(WT CK2)和盐胁迫(WT_N2)条件下的2个样品叶片进行转录组分析,鉴定紫花苜蓿叶片盐胁迫应答相关基因,从转录组水平揭示南方型紫花苜蓿适应盐胁迫环境的分子机制.提取常培养(WT CK2)和盐胁迫(WT_N2)叶片总RNA,以Illumina Hiseq 2000平台进行RNA测序(RNA Sequencing,RNA-Seq)分析.同时,对上调和下调DEGs(differential-expressed genes)进行基因本体(Gene Ontology,GO)和京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)代谢途径富集分析.选择DEGs 6个,以qRT-PCR验证RNA-Seq结果的可靠性.结果表明,滤低质量reads后,WT CK2和WT N2分别保留了62 771 040和60 394 756对高质量reads用于差异表达基因的筛选,其中52.47%和53.07%的reads能准确比对到参考序列蒺藜苜蓿(Medicago truncatula)上,说明RNA-Seq结果和参考序列可靠.DEGs鉴定结果表明,7 497个基因受盐胁迫诱导差异表达,其中上调表达4 078个,3 419下调表达,其中包括46个转录因子家族的474个转录因子基因在盐胁迫差异表达.GO富集分析表明,差异表达基因广泛涉及结合、催化活性、细胞过程、代谢过程和刺激响应.KEGG代谢分析表明,差异表达基因广泛涉及次生代谢、代谢途径、苯丙素的生物合成、黄酮类生物合成和植物激素信号转导.紫花苜蓿叶片盐胁迫响应中活性氧清除类、渗透调节和离子转运类基因上调,参与生物合成和钙依赖蛋白激酶信号转导途径,丝裂原活化蛋白激酶,PP2C(protein phosphatase 2C)基因家族、ABA(abscisic acid)通路和激素(水杨酸,乙烯和茉莉酸)信号途径基因表达上调,C3H、NAC、WRKY和AP2/EREBP转录家族因子不同程度上调,而基础代谢和蛋白合成途径总体上受到抑制.此外,候选了与盐胁迫响应相关的海藻糖-6-磷酸合成酶基因、Na+/H+逆向转运蛋白基

  10. Effect of Rain and Additives on Quality of Medicago sativa Silage%淋雨和添加剂对苜蓿青贮品质的影响

    Institute of Scientific and Technical Information of China (English)

    王永新; 蒙淑芳; 许庆方; 玉柱; 王保平; 高文俊; 贾微微; 吴璇

    2012-01-01

    The effect of rain and additives on the quality of Medicago sativa silage for fresh and rained alfalfa silage are reported. Additive treatments include control group (CK) , formic acid (FA), previous fermented juice (PFJ), improved previous fermented juice (IPFJ) . corn flour (CF), and PFJ + CF, IPFJ + CF. The pH value, ammonia-N, organic acid, nutrients and nitryl compound contents of 14 treatments were determined after 90 d ensiling period. Results showed that the pH, ammonia-N, lactic acid and acetic acid contents of alfalfa silage were significantly affected by rain and additives (P<0. 01). Lactic acid content of IPFJ + CF was significantly higher than that of CK and other treatments (P<0. 05). There was significant effect of rain and additives on DM, NDF, ADF and buffer capacity of alfalfa silage (P<0. 05). Ash, CP, EE and WSC of alfalfa silage were significantly affected by additives (P<0. 05). There were highly significant effects of raining, additives and interaction on nitrate and nitrite contents of alfalfa silage (P<0. 01). Additives can improve fermentation quality of rained alfalfa silage. The IPFJ + CF was the best additive compared to all tested ones.%为研究淋雨和添加剂对苜蓿(Medicago sativa)青贮品质的影响,试验设新鲜和淋雨苜蓿青贮2个因素,添加剂分别为对照、甲酸、绿汁发酵液、改良绿汁发酵液、玉米粉、绿汁发酵液+玉米粉、改良绿汁发酵液+玉米粉7个水平,共14个处理.青贮90 d后,测定各处理的pH、氨态氮、有机酸、营养成分和硝基化合物含量.结果表明:淋雨和添加剂均极显著降低苜蓿青贮饲料pH、氨态氮、乳酸和乙酸含量(P<0.01).改良绿汁发酵液+玉米粉组的乳酸含量显著高于对照和其他处理组(P<0.05).淋雨和添加剂显著影响苜蓿青贮饲料的干物质、酸性洗涤纤维、中性洗涤纤维含量和缓冲能值(P<0.05),添加剂对粗灰分、粗蛋白、粗脂肪

  11. Medicago sativa--Sinorhizobium meliloti Symbiosis Promotes the Bioaccumulation of Zinc in Nodulated Roots.

    Science.gov (United States)

    Zribi, Kais; Nouairi, Issam; Slama, Ines; Talbi-Zribi, Ons; Mhadhbi, Haythem

    2015-01-01

    In this study we investigated effects of Zn supply on germination, growth, inorganic solutes (Zn, Ca, Fe, and Mg) partitioning and nodulation of Medicago sativa This plant was cultivated with and without Zn (2 mM). Treatments were plants without (control) and with Zn tolerant strain (S532), Zn intolerant strain (S112) and 2 mM urea nitrogen fertilisation. Results showed that M. sativa germinates at rates of 50% at 2 mM Zn. For plants given nitrogen fertilisation, Zn increased plant biomass production. When grown with symbionts, Zn supply had no effect on nodulation. Moreover, plants with S112 showed a decrease of shoot and roots biomasses. However, in symbiosis with S532, an increase of roots biomass was observed. Plants in symbiosis with S. meliloti accumulated more Zn in their roots than nitrogen fertilised plants. Zn supply results in an increase of Ca concentration in roots of fertilised nitrogen plants. However, under Zn supply, Fe concentration decreased in roots and increased in nodules of plants with S112. Zn supply showed contrasting effects on Mg concentrations for plants with nitrogen fertilisation (increase) and plants with S112 (decrease). The capacity of M. sativa to accumulate Zn in their nodulated roots encouraged its use in phytostabilisation processes.

  12. Mixed Nodule Infection in Sinorhizobium meliloti-Medicago sativa Symbiosis Suggest the Presence of Cheating Behavior.

    Science.gov (United States)

    Checcucci, Alice; Azzarello, Elisa; Bazzicalupo, Marco; Galardini, Marco; Lagomarsino, Alessandra; Mancuso, Stefano; Marti, Lucia; Marzano, Maria C; Mocali, Stefano; Squartini, Andrea; Zanardo, Marina; Mengoni, Alessio

    2016-01-01

    In the symbiosis between rhizobia and legumes, host plants can form symbiotic root nodules with multiple rhizobial strains, potentially showing different symbiotic performances in nitrogen fixation. Here, we investigated the presence of mixed nodules, containing rhizobia with different degrees of mutualisms, and evaluate their relative fitness in the Sinorhizobium meliloti-Medicago sativa model symbiosis. We used three S. meliloti strains, the mutualist strains Rm1021 and BL225C and the non-mutualist AK83. We performed competition experiments involving both in vitro and in vivo symbiotic assays with M. sativa host plants. We show the occurrence of a high number (from 27 to 100%) of mixed nodules with no negative effect on both nitrogen fixation and plant growth. The estimation of the relative fitness as non-mutualist/mutualist ratios in single nodules shows that in some nodules the non-mutualist strain efficiently colonized root nodules along with the mutualist ones. In conclusion, we can support the hypothesis that in S. meliloti-M. sativa symbiosis mixed nodules are formed and allow non-mutualist or less-mutualist bacterial partners to be less or not sanctioned by the host plant, hence allowing a potential form of cheating behavior to be present in the nitrogen fixing symbiosis.

  13. Decomposition of olive mill waste compost, goat manure and Medicago sativa in Lebanese soils using the litterbag technique

    Science.gov (United States)

    Atallah, Therese

    2014-05-01

    Organic amendments, green manure and plant residues incorporation are the main sources of nutrients in organic farming, their decomposition rate is crucial for the accumulation and long-term storage of organic matter in soils. In this study the decomposition of compost from olive mill waste (N: 29.3 g kg-1; total dissolved nitrogen or TDN: 3.82 g kg-1), goat manure (N: 31.5 g kg-1; TDN: 0.94 g kg-1), the shoots (N: 33.6 g kg-1; TDN: 17.57 g kg-1) and roots (N: 22.12 g kg-1; TDN: 8.87 g kg-1) of Medicago sativa was followed in three Lebanese soils. The nitrogen, phosphorus and potassium released were followed over one year, starting in early winter (December-January). The mild sub-humid Mediterranean conditions allowed a rapid mass loss in alfalfa shoots 30 days after incorporation. Manure and compost were more persistent. Between 80 and 90% of TDN were released, after 30 days of in-situ incubation for compost, the release was over 90% for alfalfa shoots. The movement of P was slower, as the compost (6.99 g kg-1 of P) and manure (9.81 g kg-1 of P) lost 33% and 22%, respectively, during 30 days of incubation. After one year, 15 to 35% of P remained in the soils. The manure was the richest in potassium (19.66 g kg-1) followed by the alfalfa shoots (15.56 g kg-1), the compost (8.19 g kg-1) and the roots (5.96 g kg-1). The loss of potassium was important, as over 88% had disappeared over the year. All decomposition curves followed an exponential model. The calculated coefficients of decomposition for total nitrogen (lnfinal - lninitial/days) were significantly higher for alfalfa shoots (0.00547 day-1) and similar for the compost (0.00184 day-1) and the manure (0.00175 day-1). The ANOVA test showed a difference between two of the sites (Site A: 521 g kg-1 of clay and 42 g kg-1 of calcium carbonate; Site S: 260 g kg-1 of clay and 269 g kg-1 of CaCO3) and the third one (Site L: 315 g kg-1 of clay and 591 g kg-1 of CaCO3). The relationships between the soil calcium

  14. 不同品种紫花苜蓿(Medicago sativa)的化感效应研究%Study on Allelopathy of Medicago sativa Stem Aqueous extracts

    Institute of Scientific and Technical Information of China (English)

    董晓宁; 高承芳; 李文杨; 张晓佩

    2009-01-01

    用砂培法研究紫花苜蓿(Medicago sativa)的六个品种苗期地上部分水浸提液对鸭茅(Dactylis glomerata L.)的化感效应.结果表明,紫花苜蓿六个品种茎叶水浸提液对鸭茅的化感效应在供试品种间差异显著.游客、苜蓿对鸭茅的种子发芽及幼苗生长有抑制作用,但游客却对鸭茅的苗干重有促进作用;三得利和赛迪对鸭茅的种子发芽、根长及根干重有抑制作用,却对苗生长的影响无显著差异.此外,供试紫花苜蓿浸提液对鸭茅的化感作用,随着浓度的升高,抑制作用随之增强.

  15. Biogenic Pt uptake and nanoparticle formation in Medicago sativa and Brassica juncea

    Energy Technology Data Exchange (ETDEWEB)

    Bali, Roza [University of Sydney, Laboratory for Sustainable Technology, School of Chemical and Biomolecular Engineering (Australia); Siegele, Rainer [Australian Nuclear Science and Technology Organization, Institute for Environmental Research (Australia); Harris, Andrew T., E-mail: a.harris@usyd.edu.a [University of Sydney, Laboratory for Sustainable Technology, School of Chemical and Biomolecular Engineering (Australia)

    2010-10-15

    The ability of the facultative metallophyte plants, Medicago sativa (M. sativa) and Brassica juncea (B. juncea) to accumulate and translocate platinum (Pt) from aqueous substrates is reported. The influence of Pt concentration in the substrate (5, 10, 20, 40 and 80 ppm), exposure time (24, 48 and 72 h) and substrate pH (2, 3, 5, 7 and 9) was determined. In both plants the concentration of Pt increased with substrate concentration and exposure time. Greater accumulation was detected in the roots of M. sativa than B. juncea, up to a maximum of 94.19 mg Pt g{sup -1} (dry biomass) compared with 38.5 mg Pt g{sup -1} (dry biomass) following exposure to 80 ppm Pt after 72 h exposure, respectively. However, at lower substrate concentrations (5 and 20 ppm) greater quantities of Pt were detected in the shoots of B. juncea, ranging between 0.02 and 0.32 mg Pt g{sup -1} (dry biomass) at 5 ppm across the different time intervals studied, compared with 0.02-0.14 mg Pt g{sup -1} (dry biomass) for M. sativa, suggesting B. juncea to be a better translocator of Pt under idealised conditions at low concentrations. Higher Pt uptake was also observed in acidic media, with a maximum at pH 2 for M. sativa and pH 3 for B. juncea, indicating the role of net surface charge on the bioaccumulation of Pt. Once sequestered Pt(II) was reduced to Pt(0) due to the action of local metabolites. TEM images of M. sativa root samples showed the in vivo formation of Pt nanoparticles between 3 and 100 nm in size and of varying morphologies in the epidermal root cells. In vivo Pt distribution profiles were assessed using proton induced X-ray emission ({mu}-PIXE) spectroscopy, which showed even distribution across all tissue systems (epidermal, cortical and vascular) within the roots of both M. sativa and B. juncea.

  16. [Effects of copper stress on Medicago sativa seedlings leaf antioxidative system].

    Science.gov (United States)

    Wang, Song-hua; Zhang, Hua; He, Qing-yuan

    2011-09-01

    This paper studied the effects of different concentration (0, 10, 30, 50, and 100 micromol x L(-1)) CuSO4 on the leaf physiological and biochemical characteristics of Medicago sativa seedlings cultured with 1/4-strength Hoagland nutrient solution. In treatments 30, 50, and 100 micromol x L(-1) of CuSO4, the leaf H2O2, OH., and MDA contents and Fe-SOD and EST activities increased, and GSH and AsA contents increased significantly. With increasing concentration Cu, the POD, GR, and APX activities increased gradually, and the CAT and G6PDH activities decreased after an initial increase. In treatments >10 micromol x L(-1) of Cu, the capacity of leaf antioxidative system in reactive oxygen species scavenging increased to prevent the injury from copper-induced oxidative stress.

  17. [Control of the fermentation activity during ensilage of Lolium italicum A. Br. and Medicago sativa L].

    Science.gov (United States)

    Ozino Marletto, O I; Ambrosoli, R; Piccone, G; Biasiol, B

    1982-01-01

    Samples with different dry matter contents of Lolium italicum A. Br., Medicago sativa L., have been ensiled in hermetically sealed containers, in order to study the evolution of microflora and its activity. The principal microbial groups (coliforms, proteolytics , lactic acid bacteria, clostridia, yeasts) have been detected and enumerated, in anaerobic atmosphere, after ensiling periods of 3, 6, 10, 13, 20, 100 days. At the same time, the samples were chemically analyzed for the detection of: pH, moisture, ashes, total and ammoniacal nitrogen, total reducing sugars, lactic acid, volatile fatty acids, short chain alcohols. The relations found between chemical and microbiological data, show that a strong lactic fermentation is not enough for the inhibition of silage spoiling microorganisms, such as coliforms, yeasts, and (less) proteolytics . This phenomenon may be related to the "quality" of the lactic acid microflora, more than to the characteristics of the environment.

  18. Transfer of anthracnose resistance and pod coiling traits from Medicago arborea to M. sativa by sexual reproduction.

    Science.gov (United States)

    Armour, D J; Mackie, J M; Musial, J M; Irwin, J A G

    2008-07-01

    Five asymmetric hybrid plants were obtained between Medicago sativa (2n = 4x = 32) and Medicago arborea (2n = 4x = 32) through sexual reproduction and the use of a cytoplasmically male sterile M. sativa genotype. Over 2,000 pollinations were made to obtain these hybrids. Amplified fragment length polymorphism (AFLP) analysis showed that in the most studied hybrid (WA2273), 4% of the bands unique to the M. arborea parent were present, versus 72% for the unique M. sativa bands. This suggests that only a single M. arborea chromosome or chromosome parts has been transferred. WA2273 had 7% of AFLP bands which were not present in either parent, which is suggestive of chromosome rearrangements as would be expected if only chromosome parts or a single part had been transferred from M. arborea. Phenotypic evidence for hybridity was obtained for pod coiling (1.4 coils in WA2273 versus three coils in the M. sativa parent and its self and testcross populations, and one coil in M. arborea), and Colletotrichum trifolii race 2 resistance (transferred from the resistant M. arborea parent, as the M. sativa parent and the self populations were highly susceptible). The hybrids were self sterile, but were female fertile to a high level when crossed with 4x, but not 2x, M. sativa, indicating they were at or near 4x. Both the pod coiling trait and anthracnose resistance segregated in the progeny of testcrosses between WA2273 and M. sativa. The work demonstrates that agronomically useful traits can be introgressed into M. sativa from M. arborea by use of male sterile M. sativa and sexual reproduction.

  19. Modulation of endogenous indole-3-acetic acid biosynthesis in bacteroids within Medicago sativa nodules.

    Science.gov (United States)

    Bianco, C; Senatore, B; Arbucci, S; Pieraccini, G; Defez, R

    2014-07-01

    To evaluate the dose-response effects of endogenous indole-3-acetic acid (IAA) on Medicago plant growth and dry weight production, we increased the synthesis of IAA in both free-living and symbiosis-stage rhizobial bacteroids during Rhizobium-legume symbiosis. For this purpose, site-directed mutagenesis was applied to modify an 85-bp promoter sequence, driving the expression of iaaM and tms2 genes for IAA biosynthesis. A positive correlation was found between the higher expression of IAA biosynthetic genes in free-living bacteria and the increased production of IAA under both free-living and symbiotic conditions. Plants nodulated by RD65 and RD66 strains, synthetizing the highest IAA concentration, showed a significant (up to 73%) increase in the shoot fresh weight and upregulation of nitrogenase gene, nifH, compared to plants nodulated by the wild-type strain. When these plants were analyzed by confocal microscopy, using an anti-IAA antibody, the strongest signal was observed in bacteroids of Medicago sativa RD66 (Ms-RD66) plants, even when they were located in the senescent nodule zone. We show here a simple system to modulate endogenous IAA biosynthesis in bacteria nodulating legumes suitable to investigate which is the maximum level of IAA biosynthesis, resulting in the maximal increase of plant growth.

  20. Histological and ultrastructure changes in Medicago sativa in response to lead stress

    Directory of Open Access Journals (Sweden)

    Fatemeh

    2013-07-01

    Full Text Available In the recent years, human activities such industry and agriculture promote heavy metal release into the environment. Lead is the most contaminant metals in environment which adversely affects both plant and human life. The present study was undertaken to determine the effects of Pb on structural characteristics in Medicago sativa L. 30 days plants treated with Pb in 5 treatments (0,120, 240, 500, 1000µM Pb with 3 repeat in per treatment for 10 days. Histochemical method of lead detection revealed significant accumulation of this metal in cortex and xylem tissues in roots and in stems lead deposits on cell wall of collenchymas tissues. The analysis of scanning electron micrographs of the leaf surface of M. sativa grown on hydroponic culture treated with Pb showed an increase in the size of guard cells in adaxial surface and decrease in abaxial surface, decrease in size of stomata aperture and closure of stomata in 1000 µM Pb in medium. Alternation of epicuticular waxes is one of the most important of pollution symptoms, in our study, alteration in structure and deposition of epicuticular waxes were observed. Also anatomical characteristics of stem and root affected by Pb contamination. Under Pb toxicity, anatomical symptoms including increase the diameter of stems and root as well as amplified vascular bundles and pith area were obsreved.

  1. Dyes Extracted from Safflower, Medicago Sativa, and Ros Marinus Oficinalis as Photosensitizers for Dye-sensitized Solar Cells

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    Sofyan A. Taya

    2016-03-01

    Full Text Available In this work, three extracts of plant leaves were used as sensitizers for dye-sensitized solar cells (DSSCs. These plants are Safflower, Medicago sativa and Ros marinus oficinalis. The natural dyes were extracted before and after grinding the plant leaves. The UV-VIS absorption spectra of the three extracts in ethyl alcohol solution were measured. The DSSCs were assembled using TiO2 films on Fluorine-doped tin oxide (FTO coated glass. The DSSCs sensitized with the extracts of grinded leaves showed a better performance compared to those sensitized with un-grinded leaves with the highest efficiency of 0.115 % was obtained for the DSSC sensitized with Medicago sativa. The performance of the DSSCs sensitized with Safflower and Ros marinus oficinalis was significantly improved by acid treatment of the FTO substrates. Impedance spectroscopy of the fabricated cells was also carried out.

  2. Small RNA deep sequencing identifies novel and salt-stress-regulated microRNAs from roots of Medicago sativa and Medicago truncatula.

    Science.gov (United States)

    Long, Rui-Cai; Li, Ming-Na; Kang, Jun-Mei; Zhang, Tie-Jun; Sun, Yan; Yang, Qing-Chuan

    2015-05-01

    Small 21- to 24-nucleotide (nt) ribonucleic acids (RNAs), notably the microRNA (miRNA), are emerging as a posttranscriptional regulation mechanism. Salt stress is one of the primary abiotic stresses that cause the crop losses worldwide. In saline lands, root growth and function of plant are determined by the action of environmental salt stress through specific genes that adapt root development to the restrictive condition. To elucidate the role of miRNAs in salt stress regulation in Medicago, we used a high-throughput sequencing approach to analyze four small RNA libraries from roots of Zhongmu-1 (Medicago sativa) and Jemalong A17 (Medicago truncatula), which were treated with 300 mM NaCl for 0 and 8 h. Each library generated about 20 million short sequences and contained predominantly small RNAs of 24-nt length, followed by 21-nt and 22-nt small RNAs. Using sequence analysis, we identified 385 conserved miRNAs from 96 families, along with 68 novel candidate miRNAs. Of all the 68 predicted novel miRNAs, 15 miRNAs were identified to have miRNA*. Statistical analysis on abundance of sequencing read revealed specific miRNA showing contrasting expression patterns between M. sativa and M. truncatula roots, as well as between roots treated for 0 and 8 h. The expression of 10 conserved and novel miRNAs was also quantified by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). The miRNA precursor and target genes were predicted by bioinformatics analysis. We concluded that the salt stress related conserved and novel miRNAs may have a large variety of target mRNAs, some of which might play key roles in salt stress regulation of Medicago.

  3. The impact of CdSe/ZnS Quantum Dots in cells of Medicago sativa in suspension culture

    Directory of Open Access Journals (Sweden)

    Maycock Christopher

    2010-10-01

    Full Text Available Abstract Background Nanotechnology has the potential to provide agriculture with new tools that may be used in the rapid detection and molecular treatment of diseases and enhancement of plant ability to absorb nutrients, among others. Data on nanoparticle toxicity in plants is largely heterogeneous with a diversity of physicochemical parameters reported, which difficult generalizations. Here a cell biology approach was used to evaluate the impact of Quantum Dots (QDs nanocrystals on plant cells, including their effect on cell growth, cell viability, oxidative stress and ROS accumulation, besides their cytomobility. Results A plant cell suspension culture of Medicago sativa was settled for the assessment of the impact of the addition of mercaptopropanoic acid coated CdSe/ZnS QDs. Cell growth was significantly reduced when 100 mM of mercaptopropanoic acid -QDs was added during the exponential growth phase, with less than 50% of the cells viable 72 hours after mercaptopropanoic acid -QDs addition. They were up taken by Medicago sativa cells and accumulated in the cytoplasm and nucleus as revealed by optical thin confocal imaging. As part of the cellular response to internalization, Medicago sativa cells were found to increase the production of Reactive Oxygen Species (ROS in a dose and time dependent manner. Using the fluorescent dye H2DCFDA it was observable that mercaptopropanoic acid-QDs concentrations between 5-180 nM led to a progressive and linear increase of ROS accumulation. Conclusions Our results showed that the extent of mercaptopropanoic acid coated CdSe/ZnS QDs cytotoxicity in plant cells is dependent upon a number of factors including QDs properties, dose and the environmental conditions of administration and that, for Medicago sativa cells, a safe range of 1-5 nM should not be exceeded for biological applications.

  4. STUDY ON PHYTOEXTRACTION BALANCE OF ZN, CD, PB FROM MINE-WASTE POLLUTED SOILS BY USING MEDICAGO SATIVA AND TRIFOLIUM PRATENSE SPECIES

    Directory of Open Access Journals (Sweden)

    B. LIXANDRU

    2013-07-01

    Full Text Available For a term of two years was studied phytoextractive potential of Zn, Cd and Pb using successive culture of alfalfa (Medicago sativa and red clover (Trifolium pratense. In the experimental plot was incorporated a quantity of 20 kg mine waste per square meter, providing in soil 1209 mg Zn/kg d.s., 4.70 mg Cd/kg d.s. and 188.2 mg Pb/kg d.s. The metals content accumulated in plants was determined at the two moments of biomass harvesting, and through balance calculations we could establish the phytoextraction efficiency of the two forage-grasses species. The obtained results indicate that both perennial forage-legumes species have a good phytoextractive capacity and tolerance for Zn and Pb, especially Trifolium pratense specie. By using this species as phytoextractors on soil polluted with 3.76 times more Pb and 4.03 times more Zn, is provided the reduction of metallic ions concentration in soil to limits admitted by laws in a period of 3, respectively, 4 years.

  5. Genetic transformation and analysis of rice OsAPx2 gene in Medicago sativa.

    Science.gov (United States)

    Guan, Qingjie; Takano, Tetsuo; Liu, Shenkui

    2012-01-01

    The OsAPx2 gene from rice was cloned to produce PBI121::OsAPx2 dual-expression plants, of which expression level would be increasing under stressful conditions. The enzyme ascorbate peroxidase (APX) in the leaves and roots of the plants increased with increasing exposure time to different sodium chloride (NaCl) and hydrogen peroxide (H(2)O(2))concentrations, as indicated by protein gel blot analysis. The increased enzyme yield improved the ability of the plants to resist the stress treatments. The OsAPx2 gene was localized in the cytoplasm of epidermal onion cells as indicated by the instantaneous expression of green fluorescence. An 80% regeneration rate was observed in Medicago sativa L. plants transformed with the OsAPx2 gene using Agrobacterium tumefaciens, as indicated by specific primer PCR. The OsAPx2 gene was expressed at the mRNA level and the individual M. sativa (T#1,T#2,T#5) were obtained through assaying the generation of positive T2 using RNA gel blot analysis. When the seeds of the wild type (WT) and the T2 (T#1,T#5) were incubated in culture containing MS with NaCl for 7 days, the results as shown of following: the root length of transgenic plant was longer than WT plants, the H(2)O(2) content in roots of WT was more than of transgenic plants, the APX activity under stresses increased by 2.89 times compared with the WT, the malondialdehyde (MDA) content of the WT was higher than the transgenic plants, the leaves of the WT turned yellow, but those of the transgenic plants remained green and remained healthy. The chlorophyll content in the WT leaves was less than in the transgenic plants, after soaking in solutions of H(2)O(2), sodium sulfite (Na(2)SO(3)), and sodium bicarbonate (NaHCO(3)). Therefore, the OsAPx2 gene overexpression in transgenic M. sativa improves the removal of H(2)O(2) and the salt-resistance compared with WT plants. A novel strain of M. sativa carrying a salt-resistance gene was obtained.

  6. Genetic transformation and analysis of rice OsAPx2 gene in Medicago sativa.

    Directory of Open Access Journals (Sweden)

    Qingjie Guan

    Full Text Available The OsAPx2 gene from rice was cloned to produce PBI121::OsAPx2 dual-expression plants, of which expression level would be increasing under stressful conditions. The enzyme ascorbate peroxidase (APX in the leaves and roots of the plants increased with increasing exposure time to different sodium chloride (NaCl and hydrogen peroxide (H(2O(2concentrations, as indicated by protein gel blot analysis. The increased enzyme yield improved the ability of the plants to resist the stress treatments. The OsAPx2 gene was localized in the cytoplasm of epidermal onion cells as indicated by the instantaneous expression of green fluorescence. An 80% regeneration rate was observed in Medicago sativa L. plants transformed with the OsAPx2 gene using Agrobacterium tumefaciens, as indicated by specific primer PCR. The OsAPx2 gene was expressed at the mRNA level and the individual M. sativa (T#1,T#2,T#5 were obtained through assaying the generation of positive T2 using RNA gel blot analysis. When the seeds of the wild type (WT and the T2 (T#1,T#5 were incubated in culture containing MS with NaCl for 7 days, the results as shown of following: the root length of transgenic plant was longer than WT plants, the H(2O(2 content in roots of WT was more than of transgenic plants, the APX activity under stresses increased by 2.89 times compared with the WT, the malondialdehyde (MDA content of the WT was higher than the transgenic plants, the leaves of the WT turned yellow, but those of the transgenic plants remained green and remained healthy. The chlorophyll content in the WT leaves was less than in the transgenic plants, after soaking in solutions of H(2O(2, sodium sulfite (Na(2SO(3, and sodium bicarbonate (NaHCO(3. Therefore, the OsAPx2 gene overexpression in transgenic M. sativa improves the removal of H(2O(2 and the salt-resistance compared with WT plants. A novel strain of M. sativa carrying a salt-resistance gene was obtained.

  7. Restauración ecológica del suelo aplicando biochar (carbón vegetal), y su efecto en la producción de Medicago sativa

    OpenAIRE

    Luis Rafael Fiallos-Ortega; Luis Gerardo Flores-Mancheno; Nelson Duchi-Duchi; Cesar Ivan Flores-Mancheno; Darío Baño-Ayala; Luis Estrada-Orozco

    2015-01-01

    En la provincia de Chimborazo (Ecuador), cantón Riobamba, barrio San Pedro de las Abras, se realizó el estudio de restauración ecológica del suelo mediante la aplicación de diferentes niveles de carbón vegetal (10, 20, y 30 t.ha-1) y se evaluó su efecto en la producción forrajera de alfalfa Medicago sativa, bajo un Diseño de Bloques Completamente al Azar. Los resultados superiores se obtuvieron al aplicar 30 t.ha-1 de carbón vegetal, así: en el primer corte se alcanzó el menor tiempo de ocurr...

  8. Growth environment, harvest management and germplasm impacts on potential ethanol and crude protein yield in alfalfa

    Science.gov (United States)

    An alfalfa (Medicago sativa L) biomass energy production system would produce two products. Leaves would be separated from stems to produce a high protein feed for livestock and stems would be processed to produce ethanol. Therefore, maximum yields of both leaves and stems are essential for profitab...

  9. Incorporation of p-coumarates into the cell walls of alfalfa changes the lignin composition

    Science.gov (United States)

    In general, monocots can contain a significant amount of an ester-linked p-coumarate (pCA) in their cell walls, but its function is unclear. One hypothesis is that pCA aids in the formation of syringyl-rich regions during lignification. Alfalfa (Medicago sativa), a dicot, is a cultivated perennial f...

  10. Canopy visible and near-infrared reflectance data to estimate alfalfa nutritive attributes before harvest

    Science.gov (United States)

    Proximal sensing could help improve profit margins by timing the cutting or harvesting of alfalfa (Medicago sativa L.), in rapid assessment of nutritive values, such as total nitrogen (N), neutral detergent fiber (NDF), and acid detergent fiber (ADF) as well as nutritive quality indicators such as r...

  11. Alfalfa contains substantial 9-hydroperoxide lyase activity and a 3Z:2E-enal isomerase

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Noordermeer, M.A.; Veldink, G.A.

    1999-01-01

    Fatty acid hydroperoxides formed by lipoxygenase can be cleaved by hydroperoxide lyase resulting in the formation of short-chain aldehydes and omega-oxo acids. Plant hydroperoxide lyases use 13- or 9-hydroperoxy linoleic and linolenic acid as substrates. Alfalfa (Medicago sativa L.) has been reporte

  12. Emergence, forage production, and ion relations of alfalfa in response to saline waters

    Science.gov (United States)

    Alfalfa (Medicago sativa L) is an important crop utilized in regions under irrigation commonly impacted by salinity. In this study we evaluate the effect of salinity, as a continual process, from emergence to mature plant growth in successive harvests. We studied emergence, biomass production, salt ...

  13. “青大一号”紫花苜蓿叶蛋白提取研究%Study on Extraction Technology of Leaf Protein from Medicago sativa L.cv.Qingda No.1

    Institute of Scientific and Technical Information of China (English)

    刘晓峰; 达哇卓玛; 杨国柱

    2013-01-01

    [目的]探究“青大一号”紫花苜蓿叶蛋白的提取工艺.[方法]采用酸化加热法配合加盐法提取“青大一号”紫花苜蓿叶蛋白;以单因素试验设计考察料水比、加盐量、pH、预浸时间、絮凝时间、絮凝温度6因素对苜蓿叶蛋白粗蛋白质提取率的影响;同时设计L9(34)正交试验来确定“青大一号”紫花苜蓿的苜蓿叶蛋白最佳提取条件.[结果]“青大一号”紫花苜蓿叶蛋白的最佳提取条件:絮凝温度为70℃,料液比为1∶10,加盐量为1%,絮凝时间为5min,pH为4.[结论]为紫花苜蓿的工业化生产提供了理论依据.%[Objective] The aim was to explore the extraction technology of leaf protein from Medicago sativa L.cv.Qingda No.1.[Method] With Medicago sativa L.cv.Qingda No.1 as raw material,alfalfa LPC was extracted by acid-heating with salt method.The effects of six single factors like the rate of meal to water,salt concentration,pH,immersion time,flocculation time and flocculation temperature on the extraction rate of LPC crude protein were studied by using single experiment.Based on the results of single factor experiment,L9 (34) orthogonal experiment was conducted to study the impact of LPC extraction process and the optimum condition of extracting LPC from Medicago sativa var.Qingda No.1.[Result] The optimum conditions for LPC extraction were as followed:the flocculation temperature was 70 ℃ ; the flocculation time was 5 min; the solid-liquid ratio was 1∶10; the content of salt was 1%,and the pH was 4.[Conclusion] The research result provides theoretical basis for the industrial production of Medicago sativa.

  14. Germination of Medicago sativa is inhibited by soluble compounds in cement dust.

    Science.gov (United States)

    Lafragüeta, Cristina; García-Criado, Balbino; Arranz, Angel; Vázquez-de-Aldana, Beatriz R

    2014-01-01

    Deposition of cement dust on soils and plant surfaces is known to affect plant growth and the species composition of plant communities, but little is known about its effects (and those of its pH and constituents) on germination. Therefore, the aim of this study was to assess the toxicity of an aqueous cement extract, constituents of the extract and pH on the germination of seeds of a selected species, Medicago sativa. First, the effects of the extract were tested in assays with concentrations and exposure durations ranging from 0 to 1.0 g/mL and 4 to 96 h, respectively. At 0.8 g/mL, the extract strongly inhibited germination; a 4-h exposure reduced the germination rate, from 77 ± 1.8 to 50 ± 2.6% (mean ± SE), while 8-h exposure completely inhibited it. Further, treatment at this concentration killed the non-germinating seeds, thus the inhibition was due to toxic effects. Neither the pH of the extract nor the concentration of its main soluble elements separately (K, Ca, S, Na, or Cr) caused the toxicity since germination rates were not significantly reduced when these variables were tested individually. However, a mixture of the elements in solution reduced germination rates, suggesting that they have adverse synergistic effects.

  15. Stoichiometric characteristics of carbon, nitrogen and phosphorus in leaves of differently aged lucerne (Medicago sativa stands

    Directory of Open Access Journals (Sweden)

    Zhennan eWang

    2015-12-01

    Full Text Available Element concentration within a plant which is vital to function maintenance and adaptation to environment, may change with plant growth. However, how carbon (C, nitrogen (N and phosphorus (P vary stoichiometrically with stand growth, i.e. ages or cuts, was still untouched in perennial species. This study tested the hypothesis that lucerne (Medicago sativa C:N, C:P and N:P should change with stand age and cut. Leaf C:N, C:P and N:P changed with stand age, showing various trends in different cuts of lucerne. Generally the greatest stoichiometric ratios were measured in 8 year stand and in the 2nd cut. They were affected significantly and negatively by total N and P concentrations of leaf, but not by organic C concentration. There were significantly positive correlations among leaf C:N, C:P and N:P. However, leaf C:N, C:P and N:P were hardly affected by soil features. Conclusively, lucerne C, N and P stoichiometry are age- and cut-specific, and regulated mainly by leaf N, P concentrations and stoichiometry. There are few correlations with soil fertility. To our knowledge, it is the first try to elucidate the stoichiometry in the viewpoint of age and cut with a perennial herbaceous legume.

  16. Microbiote shift in the Medicago sativa rhizosphere in response to cyanotoxins extract exposure.

    Science.gov (United States)

    El Khalloufi, Fatima; Oufdou, Khalid; Bertrand, Marie; Lahrouni, Majida; Oudra, Brahim; Ortet, Philippe; Barakat, Mohamed; Heulin, Thierry; Achouak, Wafa

    2016-01-01

    The bloom-containing water bodies may have an impact due to cyanotoxins production on other microorganisms and aquatic plants. Where such water is being used for crops irrigation, the presence of cyanotoxins may also have a toxic impact on terrestrial plants and their rhizosphere microbiota. For that purpose, PCR-based 454 pyrosequencing was applied to phylogenetically characterize the bacterial community of Medicago sativa rhizosphere in response to cyanotoxins extract. This analysis revealed a wide diversity at species level, which decreased from unplanted soil to root tissues indicating that only some populations were able to compete for nutrients and niches in this selective habitat. Gemmatimonas, Actinobacteria, Deltaproteobacteria and Opitutae mainly inhabited the bulk soil, whereas, the root-adhering soil and the root tissues were inhabited by Gammaproteobacteria and Alphaproteobacteria. The proportion of these populations fluctuated in response to cyanotoxins extract exposure. Betaproteobacteria proportion increased in the three studied compartments, whereas Gammaproteobacteria proportion decreased except in the bulk soil. This study revealed the potential toxicity of cyanotoxins extract towards Actinobacteria, Gemmatimonas, Deltaproteobacteria, and Gammaproteobacteria, however Clostridia, Opitutae and bacteria related with Betaproteobacteria, were stimulated denoting their tolerance. Altogether, these data indicate that crop irrigation using cyanotoxins containing water might alter the rhizosphere functioning.

  17. Characterization of a novel Medicago sativa NAC transcription factor gene involved in response to drought stress.

    Science.gov (United States)

    Wang, Yong Xin

    2013-11-01

    Relying on the regulation of transcription factors, plants resist to various abiotic and biotic stresses. NAC (NAM, ATAF1/2, CUC2) are one of the largest families of plant-specific transcription factors and known to play important roles in plant development and response to environmental stresses. A new NAC gene was cloned on the basis of 503 bp EST fragment from the SSH cDNA library of Medicago sativa. It was 1,115 bp including an 816 bp ORF and encodes 271 amino acids. A highly conserved region is located from the 7th amino acid to the 315th amino acid in its N-terminal domain. The NAC protein is subcellularly localized in the nucleus of onion epidemical cells and possible functions as a transcription factor. The relative quantitative real-time RT-PCR was performed at different stress time. The results revealed that the transcription expression of NAC gene could be induced by drought, high salinity and ABA. The transgenic Arabidopsis with NAC gene has the drought tolerance better than the wild-type.

  18. Transcriptome analysis of Glomus mosseae/Medicago sativa mycorrhiza on atrazine stress.

    Science.gov (United States)

    Song, Fuqiang; Li, Jize; Fan, Xiaoxu; Zhang, Quan; Chang, Wei; Yang, Fengshan; Geng, Gui

    2016-02-02

    Arbuscular mycorrhizal fungi (AMF) protect host plants against diverse biotic and abiotic stresses, and promote biodegradation of various contaminants. In this study effect of Glomus mosseae/Medicago sativa mycorrhiza on atrazine degradation was investigated. It was observed that the atrazine degradation rates with any addition level in mycorrhizal treatments were all significantly higher than those in non-mycorrhizal treatments. When atrazine was applied at 20 mg kg(-1), the removal efficiency was up to 74.65%. Therefore, G. mosseae can be considered as ideal inhabitants of technical installations to facilitate phytoremediation. Furthermore, a total of 10.4 Gb was used for de novo transcriptome assembly, resulting in a comprehensive data set for the identification of genes corresponding to atrazine stress in the AM association. After comparative analysis with edgeR, a total of 2,060 differential expressed genes were identified, including 570 up-regulated genes and 1490 down-regulated genes. After excluding 'function unknown' and 'general function predictions only' genes, 172 up-regulated genes were obtained. The differentially expressed genes in AM association with and without atrazine stress were associated with molecular processes/other proteins, zinc finger protein, intracellular/extracellular enzymes, structural proteins, anti-stress/anti-disease protein, electron transport-related protein, and plant growth associated protein. Our results not only prove AMF has important ecological significance on atrazine degradation but also provide evidence for the molecular mechanisms of atrazine degradation by AMF.

  19. Nodule and Leaf Nitrate Reductases and Nitrogen Fixation in Medicago sativa L. under Water Stress.

    Science.gov (United States)

    Aparicio-Tejo, P; Sánchez-Díaz, M

    1982-02-01

    The effect of water stress on patterns of nitrate reductase activity in the leaves and nodules and on nitrogen fixation were investigated in Medicago sativa L. plants watered 1 week before drought with or without NO(3) (-). Nitrogen fixation was decreased by water stress and also inhibited strongly by the presence of NO(3) (-). During drought, leaf nitrate reductase activity (NRA) decreased significantly particularly in plants watered with NO(3) (-), while with rewatering, leaf NRA recovery was quite important especially in the NO(3) (-)-watered plants. As water stress progressed, the nodular NRA increased both in plants watered with NO(3) (-) and in those without NO(3) (-) contrary to the behavior of the leaves. Beyond -15.10(5) pascal, nodular NRA began to decrease in plants watered with NO(3) (-). This phenomenon was not observed in nodules of plants given water only.Upon rewatering, it was observed that in plants watered with NO(3) (-) the nodular NRA increased again, while in plants watered but not given NO(3) (-), such activity began to decrease. Nitrogen fixation increased only in plants without NO(3) (-).

  20. Assessment of stress tolerance, productivity, and forage quality in T1 transgenic alfalfa co-overexpressing ZxNHX and ZxVP1-1 from Zygophyllum xanthoxylum

    OpenAIRE

    Peng Kang; Ai-Ke Bao; Tanweer Kumar; Ya-Qing Pan; Zhulatai Bao; Fei Wang; Suo-Min Wang

    2016-01-01

    Salinization, desertification, and soil nutrient deprivation are threatening the production of alfalfa (Medicago sativa L.) in northern China. We have previously generated T0 transgenic alfalfa co-overexpressing Zygophyllum xanthoxylum ZxNHX and ZxVP1-1 genes with enhanced salt and drought tolerance. To further develop this excellent breeding material into the new forage cultivar, stress tolerance, productivity, and forage quality of T1 transgenic alfalfa (GM) were assessed in this study. The...

  1. Exploring the plant-associated bacterial communities in Medicago sativa L

    Directory of Open Access Journals (Sweden)

    Pini Francesco

    2012-05-01

    Full Text Available Abstract Background Plant-associated bacterial communities caught the attention of several investigators which study the relationships between plants and soil and the potential application of selected bacterial species in crop improvement and protection. Medicago sativa L. is a legume crop of high economic importance as forage in temperate areas and one of the most popular model plants for investigations on the symbiosis with nitrogen fixing rhizobia (mainly belonging to the alphaproteobacterial species Sinorhizobium meliloti. However, despite its importance, no studies have been carried out looking at the total bacterial community associated with the plant. In this work we explored for the first time the total bacterial community associated with M. sativa plants grown in mesocosms conditions, looking at a wide taxonomic spectrum, from the class to the single species (S. meliloti level. Results Results, obtained by using Terminal-Restriction Fragment Length Polymorphism (T-RFLP analysis, quantitative PCR and sequencing of 16 S rRNA gene libraries, showed a high taxonomic diversity as well as a dominance by members of the class Alphaproteobacteria in plant tissues. Within Alphaproteobacteria the families Sphingomonadaceae and Methylobacteriaceae were abundant inside plant tissues, while soil Alphaproteobacteria were represented by the families of Hyphomicrobiaceae, Methylocystaceae, Bradyirhizobiaceae and Caulobacteraceae. At the single species level, we were able to detect the presence of S. meliloti populations in aerial tissues, nodules and soil. An analysis of population diversity on nodules and soil showed a relatively low sharing of haplotypes (30-40% between the two environments and between replicate mesocosms, suggesting drift as main force shaping S. meliloti population at least in this system. Conclusions In this work we shed some light on the bacterial communities associated with M. sativa plants, showing that Alphaproteobacteria may

  2. Impact of gamma radiation and salinity on growth and K+/Na+balance in two populations of Medicago sativa(L.)cultivar Gabès

    Institute of Scientific and Technical Information of China (English)

    Mokhtar Rejili; DaM Telahigue; Belgacem Lachiheb; Abdessalem Mrabet; Ali Ferchichi

    2008-01-01

    The perennial Medicago sativa cv.Gabès is widely grown on saline soils in Tunisian oases.Morphological and physiological analyses of two populations(Mareth and Gannouch)were conducted in order to study the effect of salinity and gamma radiation(350 Gy)inter-action on two populations of this species.It has been shown that the two irradiated populations of Medicago sativa are fairly tolerant to salt at growth phase compared to the non-irradiated.Exposure to gamma irradiation(350 Gy),alone or in combination with salt stress,increased significantly (p<0.00 1)shoot number,stem height and chlorophyll b pigment especially for the Gannouch population,while no change occurred for the Mareth population.The presence of salt to 9 g/1 affected significantly the root biomass and induced a reduc-tion of shoot development of both control and irradiated alfalfa populations.For all treatments,plants of two populations remained able to produce and to allocate dry matter to the different organs.The survey of Na+/K+ratio showed that the growth of the aerial organs of two non-irradiated populations was at least determined by a selectivity in favour of the K+ions r2=0.97 and r2=0.59 for Mareth and Gannouch non-irradiated populations,respectively).However,the rather weak correlation detected for the irradiated populations,par-ticularly for the irradiated Gannouch.seems to be the consequence of the effect of irradiation that improved potassium availability.essential element for growth and development.Results also showed that the two irradiated populations,especially the Mareth,accumu-lated Na+ions in its photosynthetic organs.This accumulation was associated with an improvement of foliar water content at a level of salinity around 5 g/1.Such a mechanism reflects probably an inclusive behaviour of the plants and a good aptitude to use the dominant ions(Na+)for the osmotic adjustment.However,the non-irradiated populations are unable to adjust their internal osmotic potential

  3. 转基因苜蓿的研究进展%Advances in the Research of Transgenic Medicago sativa

    Institute of Scientific and Technical Information of China (English)

    李文桂; 陈雅棠

    2009-01-01

    苜蓿(Medicago sativa)是一种优良的豆科牧草,应用基因工程技术对苜蓿进行开发和改造已成为国内外研究的热点.本文综述了病毒、细菌、寄生虫、抗逆基因、品质改良基因、抗除草剂基因、单克隆抗体和工业原料等转基因苜蓿的研究进展.

  4. Short communication. Nitrogen content of residual alfalfa taproots under irrigation

    Directory of Open Access Journals (Sweden)

    S. Cela

    2013-04-01

    Full Text Available The decomposition of alfalfa (Medicago sativa L. residues can provide significant amounts of N to subsequent crops, but most of the data on this subject has been obtained from 1-2 year old alfalfa stands. The objective of this study was to determine the biomass of alfalfa taproots and their N content in irrigated alfalfa stands that are more than 2 years old. Twenty-two commercial irrigated alfalfa fields were evaluated in the Ebro Valley (Northeast Spain from 2006 to 2010. The taproot biomass in the arable layer (0 to 30 cm depth ranged from 1.8 to 10.1 Mg ha-1 and averaged 4.8 Mg ha-1. In contrast, the N concentration in alfalfa taproots was constant among fields and averaged 24.6 g N kg-1. The total amount of N contained in alfalfa taproots (0-30 cm depth ranged from 47 to 96 kg N ha-1 in 55% of the fields, ranged from 97 to 200 kg N ha-1 in 22% of the fields, and exceeded 200 kg N ha-1 in 23% of the fields. The N content of the irrigated alfalfa taproots studied here is in the upper range previously reported in other areas, mainly with younger alfalfa stands. Based on the current finding, a classification of the quality of irrigated alfalfa stands is proposed to improve the estimates of the residual-N effects of alfalfa on subsequent crops.

  5. Evaluation of METRIC-derived ET fluxes over irrigated alfalfa crop in desert conditions using scintillometer measurements

    Science.gov (United States)

    A field study on a 50-ha alfalfa (Medicago sativa L.) irrigated field was conducted to investigate the performance of the remote sensing (RS) based Mapping EvapoTranspiration at high Resolution with Internalized Calibration (METRIC) model in the estimation of evapotranspiration (ET) under the arid c...

  6. Influence of pCO2 on carbon allocation in nodulated Medicago sativa L.

    Science.gov (United States)

    Pereyra, Gabriela; Hartmann, Henrik; Ziegler, Waldemar; Michalzik, Beate; Gonzalez-Meler, Miquel; Trumbore, Susan

    2016-04-01

    Atmospheric CO2 concentrations (pCO_2) have been related to changes in plant carbon (C) availability and photosynthetic capacity, yet there is no clear consensus as to the effect of pCO2 on the plant C balance and on nitrogen fixation in symbiotic systems. We investigated how different pCO2 (Pleistocene: 170 ppm, ambient: 400 ppm and projected future: 700 ppm) influence C allocation in nodulated Medicago sativa L. We labeled 17 week old plants with depleted 13C (-34.7±1.2‰) and traced the label over a 9-day period, to assess the redistribution of newly assimilated C across different sinks, including nodules. We analyzed N concentrations in plant tissues and found no significant differences in leaves and roots across treatments. However, growth and C fixation rates increased with pCO_2, and differences were greatest between 170 ppm and 700 ppm. Across pCO2 treatments we observed a 13C-enrichment in roots compared to leaves. We further observed the highest 13C depletion of non-structural carbohydrates (NSCs) and respired CO2 in tissues of plants grown at 700 ppm, especially in leaves and nodules. Our preliminary results suggest that sink organs like roots and nodules are fed with newly-assimilated NSCs from leaves to support respiration, and especially in 170 ppm plants represented a major respiratory loss of newly assimilated C (≈ 35{%} of the total plant respiration). Our results suggest that although plant metabolic processes like photosynthesis and respiration are affected by changes in pCO_2, nitrogen acquisition in such a symbiotic system is not.

  7. Salicylic acid improves the salinity tolerance of Medicago sativa in symbiosis with Sinorhizobium meliloti by preventing nitrogen fixation inhibition.

    Science.gov (United States)

    Palma, F; López-Gómez, M; Tejera, N A; Lluch, C

    2013-07-01

    In this work we have investigated the contribution of pretreatment with 0.1 and 0.5mM salicylic acid (SA) to the protection against salt stress in root nodules of Medicago sativa in symbiosis with Sinorhizobium meliloti. SA alleviated the inhibition induced by salinity in the plant growth and photosynthetic capacity of M. sativa-S. meliloti symbiosis. In addition, SA prevented the inhibition of the nitrogen fixation capacity under salt stress since nodule biomass was not affected by salinity in SA pretreated plants. Antioxidant enzymes peroxidase (POX), superoxide dismutase (SOD), ascorbate peroxidase (APX), dehidroascorbate reductase (DHAR) and glutathione reductase (GR), key in the main pathway that scavenges H2O2 in plants, were induced by SA pretreatments which suggest that SA may participate in the redox balance in root nodules under salt stress. Catalase activity (CAT) was inhibited around 40% by SA which could be behind the increase of H2O2 detected in nodules of plants pretreated with SA. The accumulation of polyamines (PAs) synthesized in response to salinity was prevented by SA which together with the induction of 1-aminocyclopropane-l-carboxylic acid (ACC) content suggest the prevalence of the ethylene signaling pathway induced by SA in detriment of the synthesis of PAs. In conclusion, SA alleviated the negative effect of salt stress in the M. sativa-S. meliloti symbiosis through the increased level of nodule biomass and the induction of the nodular antioxidant metabolism under salt stress. The H2O2 accumulation and the PAs inhibition induced by SA in nodules of M. sativa suggest that SA activates a hypersensitive response dependent on ethylene.

  8. Haem oxygenase-1 is involved in salicylic acid-induced alleviation of oxidative stress due to cadmium stress in Medicago sativa.

    Science.gov (United States)

    Cui, Weiti; Li, Le; Gao, Zhaozhou; Wu, Honghong; Xie, Yanjie; Shen, Wenbiao

    2012-09-01

    This work examines the involvement of haem oxygenase-1 (HO-1) in salicylic acid (SA)-induced alleviation of oxidative stress as a result of cadmium (Cd) stress in alfalfa (Medicago sativa L.) seedling roots. CdCl(2) exposure caused severe growth inhibition and Cd accumulation, which were potentiated by pre-treatment with zinc protoporphyrin (ZnPPIX), a potent HO-1 inhibitor. Pre-treatment of plants with the HO-1 inducer haemin or SA, both of which could induce MsHO1 gene expression, significantly reduced the inhibition of growth and Cd accumulation. The alleviation effects were also evidenced by a decreased content of thiobarbituric acid-reactive substances (TBARS). The antioxidant behaviour was confirmed by histochemical staining for the detection of lipid peroxidation and the loss of plasma membrane integrity. Furthermore, haemin and SA pre-treatment modulated the activities of ascorbate peroxidase (APX), superoxide dismutase (SOD), and guaiacol peroxidase (POD), or their corresponding transcripts. Significant enhancement of the ratios of reduced/oxidized homoglutathione (hGSH), ascorbic acid (ASA)/dehydroascorbate (DHA), and NAD(P)H/NAD(P)(+), and expression of their metabolism genes was observed, consistent with a decreased reactive oxygen species (ROS) distribution in the root tips. These effects are specific for HO-1, since ZnPPIX blocked the above actions, and the aggravated effects triggered by SA plus ZnPPIX were differentially reversed when carbon monoxide (CO) or bilirubin (BR), two catalytic by-products of HO-1, was added. Together, the results suggest that HO-1 is involved in the SA-induced alleviation of Cd-triggered oxidative stress by re-establishing redox homeostasis.

  9. Nitrogen fertilizer enhances growth and nutrient uptake of Medicago sativa inoculated with Glomus tortuosum grown in Cd-contaminated acidic soil.

    Science.gov (United States)

    Liu, Mohan; Sun, Jian; Li, Yang; Xiao, Yan

    2017-01-01

    This study aimed to explore whether nitrogen availability could influence mycorrhizal function and their associations with host plants in Cd-contaminated acidic soils or not. A greenhouse pot experiment was conducted to assess the effects of mycorrhizal inoculation (non-mycorrhizal inoculation (NM), Glomus aggregatum (Ga), G. tortuosum (Gt) and G. versiforme (Gv)) and inorganic N amendment on the growth, nutrient and Cd uptake of Medicago sativa grown in Cd-contaminated acidic soils (10 mg Cd kg(-1) soil). AMF inoculations significantly increased the shoot and total biomass and decreased the shoot Cd concentration in comparison to plants uninoculated. N addition increased markedly concentration and content of N and decreased those of P in plants at all inoculation treatments. Shoot K, Na and Mg concentration in plants inoculated with Ga and Gv were decreased by N addition, whereas shoot K, Na, Ca and Mg concentration in plants inoculated with Gt were not negatively affected. It was observed that N addition only increased mycorrhizal colonization, shoot biomass, shoot K, Ca and Mg content of plants inoculated with Gt. Irrespective of N addition, plants with Gt inoculation got the maximum shoot and root P concentration and content, as well as P/Cd concentration molar ratio among all inoculation treatment. Neither AMF nor N fertilizer contributed to the decrease of soil exchangeable Cd and increase of soil pH. These results suggested that N fertilizer only elevated plant performance of alfalfa with Gt inoculation grown in acidic soil, by diluting Cd concentration and alleviating of nutrient deficiency, especially P.

  10. Relationship of Resistance to Meloidogyne chitwoodi (race 2) and M. hapla in Alfalfa

    OpenAIRE

    Per H McCord

    2012-01-01

    In the Pacific Northwest, alfalfa (Medicago sativa) is host to two species of root-knot nematodes, including race 2 of the Columbia root-knot nematode (Meloidogyne chitwoodi) and the northern root-knot nematode (Meloidogyne hapla). In addition to the damage caused to alfalfa itself by M. hapla, alfalfa’s host status to both species leaves large numbers of nematodes available to damage rotation crops, of which potato is the most important. A nematode-resistant alfalfa germplasm release, W12SR2...

  11. Study on the Extraction Method of Polysaccharide from Medicago Sativa%紫花苜蓿中多糖的提取方法研究

    Institute of Scientific and Technical Information of China (English)

    刘晓峰; 达哇卓玛; 杨国柱

    2013-01-01

    [Objective] The aim was to study the optimal extraction conditions of polysaccharide from Medicago sativa.[Method] The polysaccharide was extracted from Medicago sativa by using hot water extraction method.Effects of four factors like extraction time,extraction temperature,solid-liquid ratio and extraction times on the extracting rate of polysaccharide extracted from Medicago sativa were studied through single-factor experiment and orthogonal experiment.[Result] The optimal extraction conditions of polysaccharide from Medicago sativa were as followed:the extraction time was 1 h ; the extraction temperature was 95 ℃ ; the solid-liquid ratio was 1 ∶ 30 ; and the extracting time was three times.Under the above conditions,the extracting rate of polysaccharide was up to 6.1%.[Conclusion] The research results provides theoretical basis for the study and production of polysaccharide from Medicago sativa.%[目的]探究提取紫花苜蓿中多糖的最佳工艺条件.[方法]采用热水浸提法提取紫花苜蓿中多糖,并通过单因素试验和正交试验研究了浸提时间、浸提温度、浸提固液比、浸提次数对提取紫花苜蓿中多糖得率的影响.[结果]紫花苜蓿中多糖的最佳提取工艺条件为浸提时间1h、浸提温度95℃、固液比1∶30、浸提3次.在该最佳提取条件下,多糖的得率可达6.1%.[结论]为紫花苜蓿多糖的研究和生产提供了理论依据.

  12. Revisiting the Economic Injury Level and Economic Threshold Model for Potato Leafhopper (Hemiptera: Cicadellidae) in Alfalfa.

    Science.gov (United States)

    Chasen, Elissa M; Undersander, Dan J; Cullen, Eileen M

    2015-08-01

    The economic injury level for potato leafhopper, Empoasca fabae (Harris), in alfalfa (Medicago sativa L.) was developed over 30 yr ago. In response to increasing market value of alfalfa, farmers and consultants are interested in reducing the economic threshold for potato leafhopper in alfalfa. To address this question, caged field trials were established on two consecutive potato leafhopper susceptible crops in 2013. Field cages were infested with a range of potato leafhopper densities to create a linear regression of alfalfa yield response. The slopes, or yield loss per insect, for the linear regressions of both trials were used to calculate an economic injury level for a range of current alfalfa market values and control costs. This yield-loss relationship is the first quantification that could be used to help assess whether the economic threshold should be lowered, given the increased market value of alfalfa.

  13. Effect of Manganese on the Carbon-nitrogen Metabolism of Medicago sativa Seedlings%锰胁迫对紫花苜蓿幼苗碳、氮代谢的影响

    Institute of Scientific and Technical Information of China (English)

    吴旭红; 张超; 马云祥; 何旻琦

    2016-01-01

    采用沙培法,以常规锰浓度为对照,研究不同锰营养状况对苜蓿早期光合碳同化与氮代谢的影响,结果表明:锰素缺乏(T1处理:5%CK;T2处理:20%CK),苜蓿叶片1,5-二磷酸核酮糖羧化酶积累量减少,光合色素含量下降,硝酸还原酶和谷氨酰胺合成酶活性降低。锰重度过量(T4处理:20倍 CK),苜蓿幼苗碳氮代谢运转受阻,可溶性蛋白、氨基酸总量和羧肽酶活性大幅下降。5倍常规浓度的中度锰过量处理,则促进了碳素同化、氨基酸的合成和可溶性蛋白的积累。综合分析表明,中度锰过量有助于苜蓿苗期的光合碳同化和蛋白质代谢。%Alfalfa was cultivated with sand culture method,and general Mn concentration was used as control,a series of experiments were designed to explore the function and effect of Manganese on the car-bon-nitrogen metabolism of Medicago sativa seedlings.The results showed that when the manganese was deficient(T1:5%CK;T2:20%CK),the accumulation amount of Rubisco reduced,the content of photo-synthetic pigment decreased,and the activities of NR and GS declined.On the other hand,when the Man-ganese was overfeeding seriously(T4:20 times of control),the carbon-nitrogen metabolism would be in-hibited,the soluble protein,total amino acids and the activity of Rubisco decreased greatly.However,un-der light stress which were 5 times of general Mn concentration,it would be benefit to the Medicago sati-va seedlings on the protein metabolism and photosynthesis.In conclusion,a proper overfeeding of Manga-nese would promote the carbon-nitrogen metabolism and protein metabolism in Medicago sativa seed-lings.

  14. New pharmacological properties of Medicago sativa and Saponaria officinalis saponin-rich fractions addressed to Candida albicans.

    Science.gov (United States)

    Sadowska, Beata; Budzyńska, Aleksandra; Więckowska-Szakiel, Marzena; Paszkiewicz, Małgorzata; Stochmal, Anna; Moniuszko-Szajwaj, Barbara; Kowalczyk, Mariusz; Różalska, Barbara

    2014-08-01

    The antifungal activity of the saponin-rich fractions (SFs) from Medicago sativa (aerial parts and roots) and Saponaria officinalis (used as a well-known source of plant saponins) against Candida albicans reference and clinical strains, their yeast-to-hyphal conversion, adhesion, and biofilm formation was investigated. Direct fungicidal/fungistatic properties of the tested phytochemicals used alone, as well as their synergy with azoles (probably resulting from yeast cell wall instability) were demonstrated. Here, to the best of our knowledge, we report for the first time the ability of saponin-rich extracts of M. sativa and S. officinalis to inhibit C. albicans germ tube formation, limit hyphal growth, reduce yeast adherence and biofilm formation, and eradicate mature (24 h) Candida biofilm. Moreover, M. sativa SFs (mainly obtained from aerial parts), in the range of concentrations which were active modulators of Candida virulence factors, exhibited low cytotoxicity against the mouse fibroblast line L929. These properties seem to be very promising in the context of using plant-derived SFs as potential novel antifungal therapeutics supporting classic drugs or as ingredients of disinfectants.

  15. Addition of alfalfa (Medicago sativa L.) to lamb diets enhances production and profits in northern China

    Science.gov (United States)

    The agro-pastoral transitional zone of northern China is an ecologically fragile area with a short growing season and extensive livestock production, where feed shortage is a key constraint to ruminant production, especially in winter. This study was conducted to evaluate the effects of various rat...

  16. Ractopamine uptake from soil by alfalfa (Medicago sativa) and wheat (Triticum aestivum)

    Science.gov (United States)

    Ractopamine, a beta adrenergic agonist, is approved to use as feed additive in swine (Paylean®), cattle (Optaflexx®), and turkey (Topmax®) to improve daily weight gain, increase feed efficiency, and produce leaner meat. Because of this economic advantage, ractopamine is widely used. The transfer o...

  17. Collection and characterization of alfalfa (Medicago sativa L. in West Mediterranean coastal zone

    Directory of Open Access Journals (Sweden)

    Mehmet ÖTEN

    2014-12-01

    Full Text Available Alfaalfa which is the one of the most quality roughages used in the animal nutrition and also utilized as the concentrate feed is grown in wide cultivation sites in the numerous countries of the world. However, this forage crop, a native plant of Turkey, has not been given in our country as much importance as in other countries and has not been able to provide an adequate development across the country. Alfaalfa agriculture is done with the native populations on a large scale in our country and improved alfaalfa species are limited. The purpose of this study was to collect superior alfaalfa species chosen from the natural vegetation in the West Mediterranean Coast Zone, 13 counties of Antalya, propagate vegetatively the clones and transplant the clones to the field, evaluate the phenological and morphological observations and transfer the materials to the breeding programme. The features of alfaalfa genotypes differed significantly. The growth rate after harvest of some genotypes were high. Natural plant height of alfaalfa genotypes were measured as 57.86-89.03 cm, the main stem lengths were measured as 67.45-101.28 cm. The significant differences between the number of branches in the root corolla were determined. The highest number of branches in the root corolla were determined as 71.00 pcs in Gazipaşa-1 population and 69.66 pcs in Kemer-1 population. Alanya-1 population had the earliest flowering day number with the 192.50 days between the alfaalfa genotypes, the other populations flowering day numbers were between the 193.00-205.33 days. The highest total dry matter yield was determined as 949.50 g in Gazipaşa-1 population, the total dry matter yields of the other populations differed between 331.40-763.46 g. the highest crude protein rates were estimated between 17.52-16.27 % in the Gazipaşa-1, Alanya-1, Aksu-1, Aksu-2, Kepez-1, Döşemealtı-1, Konyalatı-1, Kemer-1, Kumluca-2, Finike-1, Finike-2, Demre-1, Demre-2 and Kaş-1 genotypes, the lowest crude protein rate was estimated as the 12.75 % in Kaş-2 population. As a result of the research, Gazipaşa-1, Alanya-1, Aksu-1, Aksu-2, Kepez-1, Döşemealtı-1, Kemer-1, Finike-2, Demre-1 and Kaş-1 populations were chosen for using purpose of breeding.

  18. Artificial micro RNA (amiRNA) induced gene silencing in alfalfa (Medicago sativa)

    Science.gov (United States)

    Gene silencing is a powerful technique that allows the study of the function of specific genes by selectively reducing their transcription. Several different approaches can be used; however, they all have in common the artificial generation of single-stranded small RNAs that are utilized by the endo...

  19. Resistance to uprooting of Alfalfa and Avena Sativa and related importance for flume experiments

    Science.gov (United States)

    Edmaier, K.; Crouzy, B.; Burlando, P.; Perona, P.

    2012-04-01

    Vegetation influences sediment dynamics by stabilizing the alluvial sediment with its root system. Thus, vegetation engineers the riparian ecosystem by contributing to the formation and stabilization of river bars and islands. The resistance to uprooting of young plants in non-cohesive sediment depends on the competition between flow induced drag and root growth timescales. The investigation of flow-sediment-plant interactions in situ is difficult since variables cannot be controlled and material hardly be collected. In order to investigate ecomorphological processes, laboratory experiments are essential and have gained importance in the last decade. To achieve a better understanding of the dependence of resistance to uprooting on the root system (length and structure) we conducted vertical uprooting experiments with Alfalfa and Avena Sativa which are both species that have been used in flume experiments on vegetation-flow interactions (e.g. Tal and Paola, 2010; Perona et al., in press). Seeds were seeded on quartz sand and vertically uprooted with constant velocity whereat the weight force required to uproot a seedling was measured. After uprooting, roots were scanned and analyzed and the correlation of root parameters with the uprooting work was studied. Total root length was found to be the best explanatory variable, in particular the uprooting work increases following a power law with increasing root length. The impact of other root parameters (main root length, root number, tortuosity) on the uprooting work was as well analyzed. Still, not all influencing root parameters could be captured, like the angle between roots or root hair distribution. Environmental conditions like grain size and saturation were also found to have an effect on the uprooting resistance of roots. So, lower saturated sediment results in a higher uprooting work. This work is a first step to better understand the energy regime for vegetation uprooting and its dependence on various

  20. Study on the Species and Dynamics of Pest Insects and Their Natural Enemies on Medicago sativa L. in Jinan%济南市紫花苜蓿害虫和天敌种类及其发生动态的研究

    Institute of Scientific and Technical Information of China (English)

    韩凤英; 杨慧; 秦旭; 王绍敏; 杨向黎

    2012-01-01

    为了控制紫花苜蓿害虫的危害,提高紫花苜蓿的产量和质量.2011年5-8月,本研究系统调查了济南唐王紫花苜蓿害虫和天敌昆虫的种类,分析了主要害虫及天敌的发生动态.结果表明:紫花苜蓿昆虫种类繁多,共7目14科32种,其中主要害虫有蚜虫、蓟马、叶蝉、盲蝽,主要天敌有草蛉、瓢甲、食蚜蝇等.蚜虫5-6月份危害严重,7-8月份少量发生;蓟马在紫花苜蓿的整个生长季节均有发生;叶蝉和盲蝽的发生有2个高峰期,分别在6月中旬和7月中旬.本研究为控制紫花苜蓿害虫提供直接、客观依据.%In order to control the damage of pest insect on Medicago sativa L., and improve the yield and the quality of Medicago sativa L.. In this paper, the species and population dynamic of main insect pests and their natural enemies on Medicago sativa L. In Jinan were investigated. The results showed that the species of insect pests were abundant from May to August 2011, including 7 orders, 14 families and 33 species. The dominant species of insect pests were Aphididae, Thtipidae, Cicadellidae and Miridae, and the main species of natural pest enemies were Chrysopidae, Coccinellidae and Syrphidae. Aphididae caused severe damages to Medicago sativa L. From May to June, and fewer damaged from July to August. Thtipidae invaded alfalfa throughout plant growing season. Two occurrence peaks existed in the invasion of Cicadellidae and Miridae were mid-June and mid-July. The data above provided useful information for controlling the pest insects on Medicago sativa L..

  1. Applied Genetics and Genomics in Alfalfa Breeding

    Directory of Open Access Journals (Sweden)

    E. Charles Brummer

    2012-03-01

    Full Text Available Alfalfa (Medicago sativa L., a perennial and outcrossing species, is a widely planted forage legume for hay, pasture and silage throughout the world. Currently, alfalfa breeding relies on recurrent phenotypic selection, but alternatives incorporating molecular marker assisted breeding could enhance genetic gain per unit time and per unit cost, and accelerate alfalfa improvement. Many major quantitative trait loci (QTL related to agronomic traits have been identified by family-based QTL mapping, but in relatively large genomic regions. Candidate genes elucidated from model species have helped to identify some potential causal loci in alfalfa mapping and breeding population for specific traits. Recently, high throughput sequencing technologies, coupled with advanced bioinformatics tools, have been used to identify large numbers of single nucleotide polymorphisms (SNP in alfalfa, which are being developed into markers. These markers will facilitate fine mapping of quantitative traits and genome wide association mapping of agronomic traits and further advanced breeding strategies for alfalfa, such as marker-assisted selection and genomic selection. Based on ideas from the literature, we suggest several ways to improve selection in alfalfa including (1 diversity selection and paternity testing, (2 introgression of QTL and (3 genomic selection.

  2. Gene-Silencing-Induced Changes in Carbohydrate Conformation in Relation to Bioenergy Value and Carbohydrate Subfractions in Modeled Plant (Medicago sativa) with Down-Regulation of HB12 and TT8 Transcription Factors.

    Science.gov (United States)

    Li, Xinxin; Hannoufa, Abdelali; Zhang, Yonggen; Yu, Peiqiang

    2016-05-13

    Gene silencing with RNA interference (RNAi) technology may be capable of modifying internal structure at a molecular level. This structural modification could affect biofunctions in terms of biodegradation, biochemical metabolism, and bioactive compound availability. The objectives of this study were to (1) Detect gene silencing-induced changes in carbohydrate molecular structure in an alfalfa forage (Medicago sativa spp. sativa: alfalfa) with down-regulation of genes that encode transcription factors TT8 and HB12; (2) Determine gene silencing-induced changes in nutrient bioutilization and bioavailability in the alfalfa forage (Medicago sativa); and (3) Quantify the correlation between gene silencing-induced molecular structure changes and the nutrient bioutilization and bioavailability in animals of ruminants. The experimental treatments included: T1 = Non-transgenic and no-gene silenced alfalfa forage (code "NT"); T2 = HB12-RNAi forage with HB12 gene down regulation (code "HB12"); T3 = TT8-RNAi forage with TT8 gene down regulation (code "TT8"). The HB12 and TT8 gene silencing-induced molecular structure changes were determined by non-invasive and non-destructive advanced molecular spectroscopy in a middle infrared radiation region that focused on structural, non-structural and total carbohydrate compounds. The nutrient bioutilization and bioavailability of the modified forage were determined using NRC-2001 system in terms of total digestive nutrient (TDN), truly digestible fiber (tdNDF), non-fiber carbohydrate (tdNDF), fatty acid (tdFA), crude protein (tdCP) and bioenergy profiles (digestible energy, metabolizable energy, net energy) for ruminants. The carbohydrate subfractions were evaluated using the updated CNCPS 6.0 system. The results showed that gene silencing significantly affected tdNFC (42.3 (NT) vs. 38.7 (HB12) vs. 37.4% Dry Matter (TT8); p = 0.016) and tdCP (20.8 (NT) vs. 19.4 (HB12) vs. 22.3% DM (TT8); p = 0.009). The gene-silencing also affected

  3. [Effects of shading on the aboveground biomass and stiochiometry characteristics of Medicago sativa].

    Science.gov (United States)

    Ma, Zhi-Liang; Yang, Wan-Qin; Wu, Fu-Zhong; Gao, Shun

    2014-11-01

    In order to provide scientific basis for inter-planting alfalfa in abandoned farmland, a shading experiment was conducted to simulate the effects of different light intensities on the aboveground biomass, the contents of carbon, nitrogen, phosphorus and potassium, and the stoichiometric characteristics of alfalfa under the plantation. The results showed that the aboveground biomass of alfalfa correlated significantly with the light intensity, and shading treatment reduced the aboveground biomass of alfalfa significantly. The aboveground alfalfa tissues under the 62% shading treatment had the highest contents of carbon, nitrogen and phosphorus, which was 373.73, 34.38 and 5.47 g · kg(-1), respectively, and significantly higher than those of the control. However, shading treatments had no significant effect on the potassium content of aboveground part. The C/N ratio in aboveground tissues under the 72% shading treatment was significantly higher than that of the control, but no significant differences among other treatments were found. The ratios of N/P and C/P in aboveground tissues showed a tendency that decreased firstly and then increased with the increase of light intensity.

  4. Detection of Changes in the Medicago sativa Retinoblastoma-Related Protein (MsRBR1) Phosphorylation During Cell Cycle Progression in Synchronized Cell Suspension Culture.

    Science.gov (United States)

    Ayaydin, Ferhan; Kotogány, Edit; Ábrahám, Edit; Horváth, Gábor V

    2017-01-01

    Deepening our knowledge on the regulation of the plant cell division cycle depends on techniques that allow for the enrichment of cell populations in defined cell cycle phases. Synchronization of cell division can be achieved using different plant tissues; however, well-established cell suspension cultures provide large amount of biological sample for further analyses. Here, we describe the methodology of the establishment, propagation, and analysis of a Medicago sativa suspension culture that can be used for efficient synchronization of the cell division. A novel 5-ethynyl-2'-deoxyuridine (EdU)-based method is used for the estimation of cell fraction that enters DNA synthesis phase of the cell cycle and we also demonstrate the changes in the phosphorylation level of Medicago sativa retinoblastoma-related protein (MsRBR1) during cell cycle progression.

  5. Regeneration of intergeneric somatic hybrids by protoplast fusion between Onobrychis viciaefolia and Medicago sativa

    Institute of Scientific and Technical Information of China (English)

    徐子勤; 贾敬芬

    1997-01-01

    Protoplast fusion was induced between sainfoin and alfalfa by an improved polyethyleneglycol (PEG) method. The intergeneric somatic calluses were selected based on complementation of hydroxyproline-resistance of sainfoin and hormone autonomy growth of alfalfa transformation cell line. 17 somatic hybrid plantlets were regenerat-ed. PEG could induce the tight agglutination of protoplasts. During diluting and washing process, cyclization of the linked membrane and formation of vesicle-like structures were observed, resulting in protoplast fusion. 5%-10% glycerol supplemented in the fusion inducing solution markedly increased the frequency of heterogeneous fusion. Better fusion results were obtained when mixed protoplast suspension was dripped in petri dishes in which PEG solution was previously placed. Chromosome number of regenerated hybrid buds varied from 30 to 60. The genome of hybrids in-cluded the small chromosome from sainfoin and two chromosomes with two clear constrictions from alfalfa. The hybrid

  6. Physiological and molecular characterization of lucerne (Medicago sativa L.) germplasm with improved seedling freezing tolerance

    Science.gov (United States)

    We conducted greenhouse experiments to compare 14 alfalfa germplasms for their survival following freezing. Among these germplasms are collections adapted to the Grand River National Grasslands in South Dakota. Our hypothesis was that these collections developed tolerance to survive the frigid gro...

  7. Effects of Plant Density and Water Stress on Competitive Ability and Yield of Medicago Sativa L. and Bromus tomentellus Boiss.in Mono and Mixed Cropping

    Directory of Open Access Journals (Sweden)

    S. Barati

    2016-03-01

    Full Text Available The effects of plant density and water stress on yield of Medicago sativa and Bromus tomentellus was studied. A greenhouse experiment was conducted at Isfahan University of Technology in 2013. The experiment included 18 treatments, three crop compositions (M.sativa, B. tomentellus or mixture of the two, two plant density levels, three watering regimes and four replicates, arranged in a completely randomized block design. Results showed that total yield of M. sativa mono-cropping was higher than mixed cropping and it was higher than B. tomentellus mono-cropping. Land Equivalent Ratio (LER values were less than 1 for all mixed cropping treatments, indicated the interspecific competition in mixed cropping. The biomass production per plant decreased with increasing density, competition for resource utilization and water stress. Compare of above-ground and below-ground dry matter showed that M. sativa appeared to be more constrained by intraspecific than by interspecific competition, Conversely, B. tomentellus was more suppressed by interspecific competition exerted by M. sativa than by intraspecific competition. Relative competition intensity (RCI values were positive for B. tomentellus and negative for M.sativa, implying that competitive ability of M.sativa was higher than B. tomentellus in mixed cropping .

  8. Trophic structure of amoeba communities near roots of Medicago sativa after contamination with fuel oil no. 6.

    Science.gov (United States)

    Cortés-Pérez, Sandra; Rodríguez-Zaragoza, Salvador; Mendoza-López, Ma Remedios

    2014-02-01

    Root exudation increases microbial activity, selecting bacterial and fungal communities that metabolize organic matter such as hydrocarbons. However, a strong contamination pulse of hydrocarbons around plant roots may reorganize the soil's microbial trophic structure toward amoebae feeding on bacteria. We conducted a microcosm experiment to elucidate the effect of Medicago sativa on the trophic structure of naked amoebae after a strong pulse of pollution (50,000 ppm of fuel oil no. 6, which is a mixture of long chains ranging from C10 to C28). Plants were seeded 24 h after contamination and species of amoebae in the microcosms were identified at 1, 30, and 60 days after pollution. Several species from three trophic groups of naked amoeba were still alive 24 h after the hydrocarbon pulse. Non-planted microcosms harbored three trophic groups after 60 days, while planted ones nourished four groups. The bacterivore group was the most diverse in all microcosms, followed by protist-eaters and omnivores. The quantity of amoebae was significantly higher (3.4×10(3) organisms/g soil) in the planted pots than in the non-planted ones (1.3×10(3) organisms/g soil after 30 days of pollution (P ≤ 0.01). The shortest hydrocarbon chains (C10-C14) disappeared or diminished in all microcosms, and the longest ones increased in the planted ones. M. sativa thus exerted a positive effect on species richness, quantity, and the composition of amoebae trophic groups in contaminated soil. This indirect effect on bacterial predators is another key factor underlying hydrocarbon assimilation by living organisms during phytoremediation.

  9. Involvement of abscisic acid in the response of Medicago sativa plants in symbiosis with Sinorhizobium meliloti to salinity.

    Science.gov (United States)

    Palma, F; López-Gómez, M; Tejera, N A; Lluch, C

    2014-06-01

    Legumes are classified as salt-sensitive crops with their productivity particularly affected by salinity. Abcisic acid (ABA) plays an important role in the response to environmental stresses as signal molecule which led us to study its role in the response of nitrogen fixation and antioxidant metabolism in root nodules of Medicago sativa under salt stress conditions. Adult plants inoculated with Sinorhizobium meliloti were treated with 1 μM and 10 μM ABA two days before 200 mM salt addition. Exogenous ABA together with the salt treatment provoked a strong induction of the ABA content in the nodular tissue which alleviated the inhibition induced by salinity in the plant growth and nitrogen fixation. Antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) were induced by ABA pre-treatments under salt stress conditions which together with the reduction of the lipid peroxidation, suggest a role for ABA as signal molecule in the activation of the nodular antioxidant metabolism. Interaction between ABA and polyamines (PAs), described as anti-stress molecules, was studied being detected an induction of the common polyamines spermidine (Spd) and spermine (Spm) levels by ABA under salt stress conditions. In conclusion, ABA pre-treatment improved the nitrogen fixation capacity under salt stress conditions by the induction of the nodular antioxidant defenses which may be mediated by the common PAs Spd and Spm that seems to be involved in the anti-stress response induced by ABA.

  10. The Sinorhizobium meliloti EmrR regulator is required for efficient colonization of Medicago sativa root nodules.

    Science.gov (United States)

    Santos, Mário R; Marques, Andreia T; Becker, Jörg D; Moreira, Leonilde M

    2014-04-01

    The nitrogen-fixing bacterium Sinorhizobium meliloti must adapt to diverse conditions encountered during its symbiosis with leguminous plants. We characterized a new symbiotically relevant gene, emrR (SMc03169), whose product belongs to the TetR family of repressors and is divergently transcribed from emrAB genes encoding a putative major facilitator superfamily-type efflux pump. An emrR deletion mutant produced more succinoglycan, displayed increased cell-wall permeability, and exhibited higher tolerance to heat shock. It also showed lower tolerance to acidic conditions, a reduced production of siderophores, and lower motility and biofilm formation. The simultaneous deletion of emrA and emrR genes restored the mentioned traits to the wild-type phenotype, except for survival under heat shock, which was lower than that displayed by the wild-type strain. Furthermore, the ΔemrR mutant as well as the double ΔemrAR mutant was impaired in symbiosis with Medicago sativa; it formed fewer nodules and competed poorly with the wild-type strain for nodule colonization. Expression profiling of the ΔemrR mutant showed decreased expression of genes involved in Nod-factor and rhizobactin biosynthesis and in stress responses. Expression of genes directing the biosynthesis of succinoglycan and other polysaccharides were increased. EmrR may therefore be involved in a regulatory network targeting membrane and cell wall modifications in preparation for colonization of root hairs during symbiosis.

  11. The arbuscular mycorrhizal fungus Glomus mosseae gives contradictory effects on phosphorus and arsenic acquisition by Medicago sativa Linn

    Energy Technology Data Exchange (ETDEWEB)

    Chen Baodong [Department of Soil Environmental Sciences/State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Xiao Xueyi [Department of Soil Environmental Sciences/State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Zhu Yongguan [Department of Soil Environmental Sciences/State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China)]. E-mail: ygzhu@rcees.ac.en; Smith, F. Andrew [Soil and Land Systems, School of Earth and Environmental Sciences, Waite Campus, University of Adelaide, South Australia 5005 (Australia); Miao Xie, Z. [Department of Environmental Science and Engineering, Hangzhou Dianzi University, Hangzhou 310018 (China); Smith, Sally E. [Soil and Land Systems, School of Earth and Environmental Sciences, Waite Campus, University of Adelaide, South Australia 5005 (Australia)

    2007-07-01

    Mycorrhizal fungi may play an important role in protecting plants against arsenic (As) contamination. However, little is known about the direct and indirect involvement of arbuscular mycorrhizal fungi (AMF) in detoxification mechanisms. A compartmented pot cultivation system ('cross-pots') is used here to investigate the roles of AMF Glomus mosseae in plant phosphorus (P) and As acquisition by Medicago sativa, and P-As interactions. The results indicate that fungal colonization dramatically increased plant dry weight by a factor of around 6, and also substantially increased both plant P and As contents (i.e. total uptake). Irrespective of P and As addition levels, AM plants had shoot and root P concentrations 2 fold higher, but As concentrations significantly lower, than corresponding uninoculated controls. The decreased shoot As concentrations were largely due to 'dilution effects' that resulted from stimulated growth of AM plants and reduced As partitioning to shoots. The study provides further evidence for the protective effects of AMF on host plants against As contamination, and have uncovered key aspects of underlying mechanisms. The possible application of AMF in remediation practices is discussed.

  12. Alleviation of cadmium toxicity in Medicago sativa by hydrogen-rich water

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Weiti; Gao, Cunyi; Fang, Peng [College of Life Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Lin, Guoqing [Laboratory Center of Life Sciences, Co. Laboratory of Nanjing Agricultural University and Carl Zeiss Far East, Nanjing Agricultural University, Nanjing 210095 (China); Shen, Wenbiao, E-mail: wbshenh@njau.edu.cn [College of Life Sciences, Nanjing Agricultural University, Nanjing 210095 (China)

    2013-09-15

    Highlights: • HRW can alleviate Cd-induced alfalfa seedling growth inhibition and DNA laddering. • HRW alleviates Cd-induced oxidative stress by activating antioxidant enzymes. • Cd uptake in alfalfa seedling roots was decreased by HRW. • HRW can re-establish glutathione homeostasis under Cd stress. -- Abstract: Hydrogen gas (H{sub 2}) induces plant tolerance to several abiotic stresses, including salinity and paraquat exposure. However, the role of H{sub 2} in cadmium (Cd)-induced stress amelioration is largely unknown. Here, pretreatment with hydrogen-rich water (HRW) was used to characterize physiological roles and molecular mechanisms of H{sub 2} in the alleviation of Cd toxicity in alfalfa plants. Our results showed that the addition of HRW at 10% saturation significantly decreased contents of thiobarbituric acid reactive substances (TBARS) caused by Cd, and inhibited the appearance of Cd toxicity symptoms, including the improvement of root elongation and seedling growth. These responses were related to a significant increase in the total or isozymatic activities of representative antioxidant enzymes, or their corresponding transcripts. In vivo imaging of reactive oxygen species (ROS), and the detection of lipid peroxidation and the loss of plasma membrane integrity provided further evidence for the ability of HRW to improve Cd tolerance significantly, which was consistent with a significant enhancement of the ratio of reduced/oxidized (homo)glutathione ((h)GSH). Additionally, plants pretreated with HRW accumulated less amounts of Cd. Together, this study suggested that the usage of HRW could be an effective approach for Cd detoxification and could be explored in agricultural production systems.

  13. Overexpression of a Cytosolic Ascorbate Peroxidase Gene, OsAPX2, Increases Salt Tolerance in Transgenic Alfalfa

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qian; MA Cui; XUE Xin; XU Ming; LI Jing; WU Jin-xia

    2014-01-01

    Alfalfa (Medicago sativa L.) is an important forage crop in the world and it is of great signiifcance for the improvement of its salt tolerance. To improve salt tolerance in alfalfa, a rice ascorbate peroxidase gene (OsAPX2) was introduced into alfalfa using Agrobacterium tumefaciens-mediated transformation with marker gene bar. The different T-DNA insertions in T1 transgenic alfalfa were identiifed by Southern hybridization. Three independent T2 transgenic lines were selected for stress analysis and the results showed that all of them were salt tolerant compared with wild-type plants. The transgenic plants had low levels of H2O2, malondialdehyde and relative electrical conductivity under salt and drought stresses. Moreover, the contents of chlorophyll and proline, and APX activity were high in transgenic plants under salt and drought stresses. Taken together, the overexpression of OsAPX2 enhances salt tolerance in alfalfa through scavenging reactive oxygen species.

  14. Restauración ecológica del suelo aplicando biochar (carbón vegetal, y su efecto en la producción de Medicago sativa

    Directory of Open Access Journals (Sweden)

    Luis Rafael Fiallos-Ortega

    2015-07-01

    Full Text Available En la provincia de Chimborazo (Ecuador, cantón Riobamba, barrio San Pedro de las Abras, se realizó el estudio de restauración ecológica del suelo mediante la aplicación de diferentes niveles de carbón vegetal (10, 20, y 30 t.ha-1 y se evaluó su efecto en la producción forrajera de alfalfa Medicago sativa, bajo un Diseño de Bloques Completamente al Azar. Los resultados superiores se obtuvieron al aplicar 30 t.ha-1 de carbón vegetal, así: en el primer corte se alcanzó el menor tiempo de ocurrencia a la floración (40,50 días, la mayor cobertura basal (39,35 %, la mayor cobertura aérea (86,0%, la mejor altura (87,98 cm, el mayor número de hojas por tallo (103,45 y, sobre todo, la mayor producción en forraje, tanto en materia verde (15,80 tFVha-1corte como en seca(33,38 tMSha-1año, y en el segundo corte se alcanzó la mejor cobertura basal (86,55%y aérea (95,42%, así como la mayor producción en forraje verde (15,92 t.ha-1corte y en materia seca (33,70 t.ha-1 año. El análisis económico registró la mayor rentabilidad con30 t.ha-1 de carbón vegetal con un beneficio-costo de 1,63. Se recomienda aplicar en Medicago sativa, 30 t.ha-1 de carbón vegetal, por cuanto con esa cifra se obtuvo mayor cantidad de forraje verde por corte y se mejoró la calidad del suelo, lo que garantizará obtener rentabilidades económicas que beneficien a los productores y ganaderos, además de mejorar la calidad de los suelos.

  15. Multiple centroid method to evaluate the adaptability of alfalfa genotypes

    Directory of Open Access Journals (Sweden)

    Moysés Nascimento

    2015-02-01

    Full Text Available This study aimed to evaluate the efficiency of multiple centroids to study the adaptability of alfalfa genotypes (Medicago sativa L.. In this method, the genotypes are compared with ideotypes defined by the bissegmented regression model, according to the researcher's interest. Thus, genotype classification is carried out as determined by the objective of the researcher and the proposed recommendation strategy. Despite the great potential of the method, it needs to be evaluated under the biological context (with real data. In this context, we used data on the evaluation of dry matter production of 92 alfalfa cultivars, with 20 cuttings, from an experiment in randomized blocks with two repetitions carried out from November 2004 to June 2006. The multiple centroid method proved efficient for classifying alfalfa genotypes. Moreover, it showed no unambiguous indications and provided that ideotypes were defined according to the researcher's interest, facilitating data interpretation.

  16. Lucerne transient streak virus; a Recently Detected Virus Infecting Alfafa (Medicago sativa) in Central Saudi Arabia

    Science.gov (United States)

    Raza, Ahmed; Al-Shahwan, Ibrahim M.; Abdalla, Omer A.; Al-Saleh, Mohammed A.; Amer, Mahmoud A.

    2017-01-01

    A survey was conducted to determine the status of Lucerne transient streak virus (LTSV) in three high-yielding alfalfa regions in central Saudi Arabia (Riyadh, Qassim, and Hail) during 2014. Three hundred and eight symptomatic alfalfa, and seven Sonchus oleraceus samples were collected. DAS-ELISA indicated that 59 of these samples were positive to LTSV. Two isolates of LTSV from each region were selected for molecular studies. RT-PCR confirmed the presence of LTSV in the selected samples using a specific primer pair. Percentage identity and homology tree comparisons revealed that all Saudi isolates were more closely related to each other but also closely related to the Canadian isolate-JQ782213 (97.1–97.6%) and the New Zealand isolate-U31286 (95.8–97.1%). Comparing Saudi isolates of LTSV with ten other sobemoviruses based on the coat protein gene sequences confirmed the distant relationship between them. Eleven out of fourteen plant species used in host range study were positive to LTSV. This is the first time to document that Trifolium alexandrinum, Nicotiana occidentalis, Chenopodium glaucum, and Lathyrus sativus are new host plant species for LTSV and that N. occidentalis being a good propagative host for it. PMID:28167887

  17. Lucerne transient streak virus; a Recently Detected Virus Infecting Alfafa (Medicago sativa) in Central Saudi Arabia.

    Science.gov (United States)

    Raza, Ahmed; Al-Shahwan, Ibrahim M; Abdalla, Omer A; Al-Saleh, Mohammed A; Amer, Mahmoud A

    2017-02-01

    A survey was conducted to determine the status of Lucerne transient streak virus (LTSV) in three high-yielding alfalfa regions in central Saudi Arabia (Riyadh, Qassim, and Hail) during 2014. Three hundred and eight symptomatic alfalfa, and seven Sonchus oleraceus samples were collected. DAS-ELISA indicated that 59 of these samples were positive to LTSV. Two isolates of LTSV from each region were selected for molecular studies. RT-PCR confirmed the presence of LTSV in the selected samples using a specific primer pair. Percentage identity and homology tree comparisons revealed that all Saudi isolates were more closely related to each other but also closely related to the Canadian isolate-JQ782213 (97.1-97.6%) and the New Zealand isolate-U31286 (95.8-97.1%). Comparing Saudi isolates of LTSV with ten other sobemoviruses based on the coat protein gene sequences confirmed the distant relationship between them. Eleven out of fourteen plant species used in host range study were positive to LTSV. This is the first time to document that Trifolium alexandrinum, Nicotiana occidentalis, Chenopodium glaucum, and Lathyrus sativus are new host plant species for LTSV and that N. occidentalis being a good propagative host for it.

  18. Influence of papermill sludge on growth of Medicago sativa, Festuca rubra and Agropyron trachycaulum in gold mine tailings: A greenhouse study

    Energy Technology Data Exchange (ETDEWEB)

    Green, Scott [Department of Botany, University of Manitoba, 505 Buller building, Winnipeg, Manitoba R3T 2N2 (Canada); Renault, Sylvie [Department of Botany, University of Manitoba, 505 Buller building, Winnipeg, Manitoba R3T 2N2 (Canada)], E-mail: renaults@cc.umanitoba.ca

    2008-02-15

    A greenhouse study was undertaken to determine the suitability of adding papermill sludge to neutral/alkaline gold mine tailings to improve the establishment of Festuca rubra, Agropyron trachycaulum and Medicago sativa. Festuca rubra root and shoot biomass and A. Trachycaulum shoot biomass were increased with papermill sludge amendment. The addition of papermill sludge and fertilizer drastically increased the shoot and root biomass of M. sativa (20-30 times) while A. trachycaulum and F. rubra showed a more moderate increase in growth. Photosynthetic pigment content of the leaves was higher in papermill sludge treatments than in the treatments without papermill sludge. The organic carbon content, macro-aggregate content and field capacity of the gold mine tailings were increased while the bulk density was decreased by the addition of papermill sludge. This study suggests that addition of papermill sludge and adequate fertilization can alleviate some of the adverse conditions of neutral/alkaline gold mine tailings. - Addition of papermill sludge and adequate fertilization of neutral gold mine tailings increased growth of Medicago sativa, Festuca rubra and Agropyron trachycaulum.

  19. THE EFFECT OF BIOSOLIDS ON MEDICAGO SATIVA AND FESTUCA ARUNDINACEEA PLANTS PHYTOREMEDIATION PROCESS OF WASTE DUMP

    Directory of Open Access Journals (Sweden)

    B. LIXANDRU

    2013-12-01

    Full Text Available The storage of waste dump gravely deteriorates the soil’s physical, chemical and biological properties, both in the storage area and the surrounding zones. In time, serious perturbations may occur in the biocenosis from the surrounding ecosystems, through the sweeping away of the inorganic matter or through precipitations. The main problem in this case is to find the most suitable phytoremediation method for these waste dumps, by sowing plant species (grasses, in order to stop the erosion generated by wind and rain. Establishing a herbaceous “carpet” , in time, is very difficult, because the waste dump contains no organic matter, has a weak water retaining capacity and has a high bareness index. The purpose of this study was the experimentation of a method of cultivating the waste dumps using alfalfa, fescue and biosolids as fertilizers.

  20. Isolation and functional characterization of a Medicago sativa L. gene, MsLEA3-1.

    Science.gov (United States)

    Bai, Yongqin; Yang, Qingchuan; Kang, Junmei; Sun, Yan; Gruber, Margaret; Chao, Yuehui

    2012-03-01

    A full-length cDNA of 1,728 nt, called MsLEA3-1, was cloned from alfalfa by rapid amplification of cDNA ends from an expressed sequence tag homologous to soybean pGmPM10 (accession No. AAA91965.1). MsLEA3-1, encodes a deduced protein of 436 amino acids, a calculated molecular weight of 47.0 kDa, a theoretical isoelectric point of 5.18, and closest homology with late embryogenesis abundant proteins in soybean. Sequence homology suggested a signal peptide in the N terminus, and subcellular localization with GFP revealed that MsLEA3-1 was localized preferentially to the nucleolus. The transcript titre of MsLEA3-1 was strongly enriched in leaves compared with roots and stems of mature alfalfa plants. Gene expression of MsLEA3-1 was strongly induced when seedlings were treated with NaCl and ABA. Expression of the MsLEA3-1 transgenic was detected in transgenic tobacco. Malondialdehyde content and, electrical conductivity content were reduced and electrical conductivity and proline content were increased in transgenic tobacco compared with non-transgenic tobacco under salt stress. The results showed that accumulation of the MsLEA3-1 protein in the vegetative tissues of transgenic plants enhanced their tolerance to salt stress. These results demonstrate a role for the MsLEA3-1 protein in stress protection and suggest the potential of the MsLEA3-1 gene for genetic engineering of salt tolerance.

  1. 紫花苜蓿茎尖离体再生体系的建立%Establishment of Vitro Regeneration System in Medicago sativa Stem Tip

    Institute of Scientific and Technical Information of China (English)

    郭永霞; 孙强; 王丽艳; 荆瑞勇; 殷奎德

    2013-01-01

    以紫花苜蓿的成熟种子为外植体,以组培苗茎尖为材料建立了紫花苜蓿离体再生体系。研究结果显示:紫花苜蓿茎尖分化增殖的最佳培养基为MS+6-BA1.5 mg·L-1+NAA0.1 mg·L-1,平均增殖系数为6.25;最适生根培养基为MS+IBA0.05 mg·L-1,平均侧根数为28.5条,生根率达到93.5%。该再生体系的建立为紫花苜蓿遗传转化后转基因植株的快速繁殖奠定了基础。%A vitro regeneration system was established using the stem tip of tissue seedling as the material and the ripe seeds of Medicago sativa L. were used as explants. The results showed that MS with 6-BA1.5 mg·L-1+NAA0.1 mg·L-1 was the optimal medium for differentiation and proliferation of stem tip in Medicago sativa L.,and average proliferation coefficient was 6.25;MS with IBA 0.05 mg·L -1 was the optimal rooting medium,and the average side root number and the rooting rate respectively was 28.5,93.5%. The establishment of the regeneration system provided a foundation for genetic transformation and rapid propagation of Medicago sativa L.

  2. Respuestas morfológicas y fisiológicas de Rhizophagus intraradices y Medicago sativa ante contaminación por diésel.

    OpenAIRE

    Hernández Ortega, Herminia Alejandra

    2014-01-01

    Este estudio evaluó el crecimiento, cambios morfológicos, actividades fisiológicas y expresión de genes en Medicago sativa en respuesta al estrés por la contaminación con diésel, y por la inoculación del hongo micorrízico arbuscular Rhizophagus intraradices. Este trabajo fue dividido en cuatro capítulos que describen cuatro diferentes fases experimentales. El primer capítulo describe el efecto del diésel en el desarrollo y colonización de R. intraradices. El segundo capítulo presenta resultad...

  3. Contrasting impacts of defoliation on root colonization by arbuscular mycorrhizal and dark septate endophytic fungi of Medicago sativa.

    Science.gov (United States)

    Saravesi, K; Ruotsalainen, A L; Cahill, J F

    2014-05-01

    Individual plants typically interact with multiple mutualists and enemies simultaneously. Plant roots encounter both arbuscular mycorrhizal (AM) and dark septate endophytic (DSE) fungi, while the leaves are exposed to herbivores. AMF are usually beneficial symbionts, while the functional role of DSE is largely unknown. Leaf herbivory may have a negative effect on root symbiotic fungi due to decreased carbon availability. However, evidence for this is ambiguous and no inoculation-based experiment on joint effects of herbivory on AM and DSE has been done to date. We investigated how artificial defoliation impacts root colonization by AM (Glomus intraradices) and DSE (Phialocephala fortinii) fungi and growth of Medicago sativa host in a factorial laboratory experiment. Defoliation affected fungi differentially, causing a decrease in arbuscular colonization and a slight increase in DSE-type colonization. However, the presence of one fungal species had no effect on colonization by the other or on plant growth. Defoliation reduced plant biomass, with this effect independent of the fungal treatments. Inoculation by either fungal species reduced root/shoot ratios, with this effect independent of the defoliation treatments. These results suggest AM colonization is limited by host carbon availability, while DSE may benefit from root dieback or exudation associated with defoliation. Reductions in root allocation associated with fungal inoculation combined with a lack of effect of fungi on plant biomass suggest DSE and AMF may be functional equivalent to the plant within this study. Combined, our results indicate different controls of colonization, but no apparent functional consequences between AM and DSE association in plant roots in this experimental setup.

  4. Arbuscular mycorrhizal mediation of biomass-density relationship of Medicago sativa L. under two water conditions in a field experiment.

    Science.gov (United States)

    Zhang, Qian; Xu, Liming; Tang, Jianjun; Bai, Minge; Chen, Xin

    2011-05-01

    The biomass-density relationship (whereby the biomass of individual plants decreases as plant density increases) has generally been explained by competition for resources. Arbuscular mycorrhizal fungi (AMF) are able to affect plant interactions by mediating resource utilization, but whether this AMF-mediated interaction will change the biomass-density relationship is unclear. We conducted an experiment to test the hypothesis that AMF will shift the biomass-density relationship by affecting intraspecific competition. Four population densities (10, 100, 1,000, or 10,000 seedlings per square meter) of Medicago sativa L. were planted in field plots. Water application (1,435 or 327.7 mm/year) simulated precipitation in wet areas (sufficient water) and arid areas (insufficient water). The fungicide benomyl was applied to suppress AMF in some plots ("low-AMF" treatment) and not in others ("high-AMF" treatment). The effect of the AMF treatment on the biomass-density relationship depended on water conditions. High AMF enhanced the decrease of individual biomass with increasing density (the biomass-density line had a steeper slope) when water was sufficient but not when water was insufficient. AMF treatment did not affect plant survival rate or population size but did affect absolute competition intensity (ACI). When water was sufficient, ACI was significantly higher in the high-AMF treatment than in the low-AMF treatment, but ACI was unaffected by AMF treatment when water was insufficient. Our results suggest that AMF status did not impact survival rate and population size but did shift the biomass-density relationship via effects on intraspecific competition. This effect of AMF on the biomass-density relationship depended on the availability of water.

  5. Responses of lucerne (Medicago sativa L.) and rhizobia to copper-based fungicide application in two contrasting soils

    Science.gov (United States)

    Schneider, Martin; Dober, Melanie; Jöchlinger, Lisa; Keiblinger, Katharina; Soja, Gerhard; Mentler, Axel; Zechmeister-Boltenstern, Sophie; Bruckner, Alexander; Golestani Fard, Alireza; Wenzel, Walter; Zehetner, Franz

    2016-04-01

    For more than 120 years, salts of copper (Cu) have been used in viticulture to prevent damages by fungal diseases. Due to restrictions in the use of synthetic fungicides and mineral fertilizers, organic viticulture depends on Cu as well as on biological nitrogen fixation. Here, we conducted an eco-toxicological pot experiment with an acidic, sandy soil and a calcareous, loamy soil and incrementally increasing fungicide application rates from 0 to 5000 mg Cu kg-1 soil. Lucerne (Medicago sativa L. cultivar. Plato) was grown in the pots for 3 months under greenhouse conditions. Acetylene reduction assays performed with harvested nodules showed no response to elevated soil Cu concentrations indicating that the nitrogen fixing capacity of rhizobia was not compromised by Cu in our experiment. Nevertheless, the nodule biomass was very sensitive to Cu and strongly decreased due to reduced amounts of fine roots and less energy supply by the plant. Legumes are known to be Cu-sensitive, and our contribution also showed a decrease in harvest by 50 % (EC50) at 21 mg kg-1 plant Cu tissue concentration in the acidic soil and at 30 mg kg-1 in the calcareous soil. This corresponded to diffusional fluxes measured by diffusive gradients in thin films (DGT) of 202 and 368 fmol cm-2 s-1, respectively. DGT measurements showed that in the acidic soil, Cu was 2 to 10 times more available for plants, depending on the concentration applied, than in the calcareous soil. A modeling approach for estimating the effective concentration (EC) by including the DGT-estimated plant Cu content and the pH produced more accurate values (NRMSE of 21.9 to 20.1 %) than EC directly estimated from DGT.

  6. Alleviation of cadmium toxicity in Medicago sativa by hydrogen-rich water.

    Science.gov (United States)

    Cui, Weiti; Gao, Cunyi; Fang, Peng; Lin, Guoqing; Shen, Wenbiao

    2013-09-15

    Hydrogen gas (H₂) induces plant tolerance to several abiotic stresses, including salinity and paraquat exposure. However, the role of H₂ in cadmium (Cd)-induced stress amelioration is largely unknown. Here, pretreatment with hydrogen-rich water (HRW) was used to characterize physiological roles and molecular mechanisms of H₂ in the alleviation of Cd toxicity in alfalfa plants. Our results showed that the addition of HRW at 10% saturation significantly decreased contents of thiobarbituric acid reactive substances (TBARS) caused by Cd, and inhibited the appearance of Cd toxicity symptoms, including the improvement of root elongation and seedling growth. These responses were related to a significant increase in the total or isozymatic activities of representative antioxidant enzymes, or their corresponding transcripts. In vivo imaging of reactive oxygen species (ROS), and the detection of lipid peroxidation and the loss of plasma membrane integrity provided further evidence for the ability of HRW to improve Cd tolerance significantly, which was consistent with a significant enhancement of the ratio of reduced/oxidized (homo)glutathione ((h)GSH). Additionally, plants pretreated with HRW accumulated less amounts of Cd. Together, this study suggested that the usage of HRW could be an effective approach for Cd detoxification and could be explored in agricultural production systems.

  7. Effect of Medicago sativa L. and compost on organic and inorganic pollutant removal from a mixed contaminated soil and risk assessment using ecotoxicological tests.

    Science.gov (United States)

    Marchand, Charlotte; Hogland, William; Kaczala, Fabio; Jani, Yahya; Marchand, Lilian; Augustsson, Anna; Hijri, Mohamed

    2016-11-01

    Several Gentle Remediation Options (GRO), e.g., plant-based options (phytoremediation), singly and combined with soil amendments, can be simultaneously efficient for degrading organic pollutants and either stabilizing or extracting trace elements (TEs). Here, a 5-month greenhouse trial was performed to test the efficiency of Medicago sativa L., singly and combined with a compost addition (30% w/w), to treat soils contaminated by petroleum hydrocarbons (PHC), Co and Pb collected at an auto scrap yard. After 5 months, total soil Pb significantly decreased in the compost-amended soil planted with M. sativa, but not total soil Co. Compost incorporation into the soil promoted PHC degradation, M. sativa growth and survival, and shoot Pb concentrations [3.8 mg kg(-1) dry weight (DW)]. Residual risk assessment after the phytoremediation trial showed a positive effect of compost amendment on plant growth and earthworm development. The O2 uptake by soil microorganisms was lower in the compost-amended soil, suggesting a decrease in microbial activity. This study underlined the benefits of the phytoremediation option based on M. sativa cultivation and compost amendment for remediating PHC- and Pb-contaminated soils.

  8. Physiological Responses of Medicago sativa L. cv. Zhaodong to High Temperature Stress%肇东苜蓿对高温的生理响应

    Institute of Scientific and Technical Information of China (English)

    姜义宝; 王成章; 崔国文

    2009-01-01

    高温对紫花苜蓿(Medicago sativa L.)产生伤害,使其生长缓慢,易生病害,以肇东苜蓿(Medicago sativa L. cv. zhaodong)为材料,研究在40℃高温胁迫条件下叶片细胞膜相对透性、叶绿素含量、抗氧化系统和叶绿素荧光特性等生理指标的变化情况.结果表明:随高温时间的延长,肇东苜蓿叶片的细胞膜相对透性和丙二醛(MDA)含量增高,叶绿素含量、过氧化物酶(POD)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)等抗氧化系统以及叶绿素荧光Fv/Fm、Fv/Fo呈降低的变化趋势.高温下生理指标的改变,可为高温地区肇东苜蓿栽培管理和抗热苜蓿品种选育提供理论依据.

  9. Influence of Different Processing Methods on Germination of Medicago Sativa under Drought Conditions%不同处理对紫花苜蓿在干旱条件下种子萌发的影响

    Institute of Scientific and Technical Information of China (English)

    关旭; 赵良瑞; 樊凯; 唐春强; 杨淑慎

    2013-01-01

    [purpose] In order to find out an effective method to enhance vigor of Medicago sativa seeds and drought function. [methods] Five different processing methods were used to treat alfalfa seeds, including immersion in CaCl2 solution, immersion in hot water and microwave heating. After treatment, germination energy, germination rate, root length, germination index and vitality index were discussed, which in drought conditions simulated by 20% PEG-6000 solution.[results] The results show that immersion in CaCl2 solution and 25~35℃water improved germination, while microwave heating restrained germination.%[目的]为了寻找一种在干旱条件下,能提高紫花苜蓿种子活力,增强其幼苗抗旱机能的有效方法。[方法]采取CaCl2溶液浸泡、水浴加热及微波辐射等3种不同方法对紫花苜蓿种子进行预处理,在20%的PEG-6000溶液模拟干旱条件下,研究其发芽率,发芽势及种子活力指数的影响。[结论]CaCl2溶液浸泡及25~35℃之间水浴加热处理对紫花苜蓿种子的萌发有促进作用,高温水浴加热及微波辐射处理对紫花苜蓿种子的萌发有抑制作用。

  10. Alfalfa microsymbionts from different ITS and nodC lineages of Ensifer meliloti and Ensifer medicae symbiovar meliloti establish efficient symbiosis with alfalfa in Spanish acid soils.

    Science.gov (United States)

    Ramírez-Bahena, Martha-Helena; Vargas, Margarita; Martín, María; Tejedor, Carmen; Velázquez, Encarna; Peix, Álvaro

    2015-06-01

    Alfalfa (Medicago sativa L.) is an important crop worldwide whose cropping in acid soils is hampered by the poor nodulation and yield commonly attributed to the sensitivity of its endosymbionts to acid pH. In this work, we isolated several acid-tolerant strains from alfalfa nodules in three acid soils in northwestern Spain. After grouping by RAPD fingerprinting, most strains were identified as Ensifer meliloti and only two strains as Ensifer medicae according to their 16S-23S intergenic spacer (ITS) sequences that allowed the differentiation of two groups within each one of these species. The two ITS groups of E. meliloti and the ITS group I of E. medicae have been previously found in Medicago nodules; however, the group II of E. medicae has been only found to date in Prosopis alba nodules. The analysis of the nodC gene showed that all strains isolated in this study belong to the symbiovar meliloti, grouping with the type strains of E. meliloti or E. medicae, but some harboured nodC gene alleles different from those found to date in alfalfa nodules. The strains of E. medicae belong to the symbiovar meliloti which should be also recognised in this species, although they harboured a nodC allele phylogenetically divergent to those from E. meliloti strains. Microcosm experiments showed that inoculation of alfalfa with selected acid-tolerant strains significantly increased yields in acid soils representing a suitable agricultural practice for alfalfa cropping in these soils.

  11. Influence of atmospheric [CO2] on growth, carbon allocation and cost of plant tissues on leaf nitrogen concentration maintenance in nodulated Medicago sativa

    Science.gov (United States)

    Pereyra, Gabriela; Hartmann, Henrik; Ziegler, Waldemar; Michalzik, Beate; Gonzalez-Meler, Miquel; Trumbore, Susan

    2015-04-01

    Plant carbon (C) allocation and plant metabolic processes (i.e. photosynthesis and respiration) can be affected by changes in C availability, for example from changing atmospheric [CO2]. In nodulated plants, C availability may also influence nitrogen (N) fixation by bacteriods. But C allocation and N fixation are often studied independently and hence do not allow elucidating interactive effects. We investigated how different atmospheric [CO2] (Pleistocene: 170 ppm, ambient: 400 ppm and projected future: 700 ppm) influence plant growth, allocation to nodules, and the ratio of photosynthesis-to-respiration (R:A) as an indicator of C cost in Medicago sativa inoculated with Ensifer meliloti. M. sativa grew c. 38% more nodules at 400 ppm and 700 ppm than at 170 ppm. However, ratios of above- and belowground plant biomass to nodule biomass were constant over time and independent of atmospheric [CO2]. Total non-structural carbohydrate concentrations were not significantly different between plants grown at 400 and 700 ppm, but were four to five-fold higher than in 170 ppm plants. Leaf level N concentration was similar across treatments, but N-based photosynthetic rates were 82% and 93% higher in leaves of plants grown at 400 and 700 ppm, respectively, than plants grown at 170 ppm. In addition, leaf R:A was greater (48% or 55%) in plants grown at 170 ppm than plants grown at 400 and 700 ppm. Similarly, the greatest proportion of assimilated CO2 released by root respiration occurred in rhizobial plants growing at 170 ppm. Our results suggest that C limitation in nodulated Medicago sativa plants did not influence C allocation to nodule biomass but caused a proportionally greater allocation of C to belowground respiration, most likely to bacteriods. This suggests that N tissue concentration was maintained at low [CO2] by revving up bacteriod metabolism and at the expense of non-structural carbohydrate reserves.

  12. 基于Biolog-ECO技术不同退耕年限苜蓿地土壤微生物功能多样性分析%Analysis on Functional Diversity of Edaphon Communities in Medicago sativa Fields of Different Growth Years Based on Biolog-ECO Plates

    Institute of Scientific and Technical Information of China (English)

    董立国; 蒋齐; 蔡进军; 张源润; 许浩; 李生宝

    2011-01-01

    运用Biolog-ECO技术,分析半干旱黄土丘陵区不同生长年限紫花苜蓿(Medicago sativa)地和坡耕地土壤微生物功能多样性。结果表明:①在0~15 cm土层,平均吸光值总体变化趋势为生长旺盛苜蓿地显著优于极度退化苜蓿地、退化苜蓿地和坡耕地,坡耕地最差;在15~30 cm土层,平均吸光值总体变化趋势为极度退化苜蓿地平均吸光值最大,即活性最强,退化苜蓿地最低。②0~15 cm土壤微生物Shannon-Wiener指数、Pielou均匀度指数、Simpson指数、丰富度指数总体趋势,苜蓿地高于坡耕地%In this paper,the Biolog-ECO plates(Biolog,USA) were used to study the functional diversity of edaphon communities in Medicago sativa fields of different growth years in a semiarid loess hilly region.The results are as follows:(1) In the 0-15 cm soil layer,the average absorbance value in vigorous Medicago sativa fields was significantly higher than that in the severely degenerated Medicago sativa fields,degenerated Medicago sativa fields and slope farmland,especially the slope farmland;in the 15-30 cm soil layer,the average absorbance value of severely degenerated Medicago sativa fields was the highest,and it was the lowest in degenerated Medicago sativa fields;(2) In the 0-15 cm soil layer,the Shannon-Wiener index,Pielou index,Simpson index and richness index of Medicago sativa fields were holistically higher than those of slope farmland.In the 15-30 cm soil layer,the diversity index of edaphon of slope farmland was similar to that of severely degenerated Medicago sativa fields but higher than that of degenerated Medicago sativa fields and vigorous Medicago sativa fields,and that of degenerate Medicago sativa fields was the lowest;(3) Principal component analysis(PCA) of functional diversity of edaphon reveals that the functional diversity of edaphon in soil layers of 0-15 cm and 15-30 cm of slope farmland was similar to that of degenerated

  13. Nodulation by Sinorhizobium meliloti originated from a mining soil alleviates Cd toxicity and increases Cd-phytoextraction in Medicago sativa L.

    Directory of Open Access Journals (Sweden)

    Tahar eGhnaya

    2015-10-01

    Full Text Available Besides their role in nitrogen supply to the host plants by the process of symbiotic N fixation, the association between legumes and Rhizobium could be interesting also for the rehabilitation of metal contaminated soils by phytoextraction. A major limitation is however the metal sensitivity of the bacterial strains. The aim of this work was to explore the usefulness of Sinorhizobium meliloti originated from a mining site in phytoextraction of Cd by Medicago sativa. Inoculated and non-inoculated plants were cultivated for 60 d on soils containing 50 or 100 mg Cd kg-1 soil. The inoculation hindered the occurrence of Cd- induced toxicity symptoms that appeared in the shoots of non-inoculated plants. This positive effect of S.meliloti colonization was accompanied by an increase in biomass production and improved nutrient acquisition as compared to non-inoculated plants. Moreover, nodulation enhanced both Cd absorption by the roots and Cd transloaction to the shoots. The amelioration of plant biomass concomitantly with the increase in Cd shoot concentration in inoculated plants led to higher potential of Cd-phytoextraction in these plants. Hence, in the presence of 50 mg Cd kg-1 in the soil, the quantities of Cd extracted in the shoots were 58 and 178 µg plant-1 in non-inoculated and inoculated plants, respectively. Thus we suggest that this association M. sativa-S. meliloti is an efficient biological system to extract Cd.

  14. Expression of the R2R3-MYB transcription factor TaMYB14 from Trifolium arvense activates proanthocyanidin biosynthesis in the legumes Trifolium repens and Medicago sativa.

    Science.gov (United States)

    Hancock, Kerry R; Collette, Vern; Fraser, Karl; Greig, Margaret; Xue, Hong; Richardson, Kim; Jones, Chris; Rasmussen, Susanne

    2012-07-01

    Proanthocyanidins (PAs) are oligomeric flavonoids and one group of end products of the phenylpropanoid pathway. PAs have been reported to be beneficial for human and animal health and are particularly important in pastoral agricultural systems for improved animal production and reduced greenhouse gas emissions. However, the main forage legumes grown in these systems, such as Trifolium repens and Medicago sativa, do not contain any substantial amounts of PAs in leaves. We have identified from the foliar PA-accumulating legume Trifolium arvense an R2R3-MYB transcription factor, TaMYB14, and provide evidence that this transcription factor is involved in the regulation of PA biosynthesis in legumes. TaMYB14 expression is necessary and sufficient to up-regulate late steps of the phenylpropanoid pathway and to induce PA biosynthesis. RNA interference silencing of TaMYB14 resulted in almost complete cessation of PA biosynthesis in T. arvense, whereas Nicotiana tabacum, M. sativa, and T. repens plants constitutively expressing TaMYB14 synthesized and accumulated PAs in leaves up to 1.8% dry matter. Targeted liquid chromatography-multistage tandem mass spectrometry analysis identified foliar PAs up to degree of polymerization 6 in leaf extracts. Hence, genetically modified M. sativa and T. repens plants expressing TaMYB14 provide a viable option for improving animal health and mitigating the negative environmental impacts of pastoral animal production systems.

  15. Nodulation by Sinorhizobium meliloti originated from a mining soil alleviates Cd toxicity and increases Cd-phytoextraction in Medicago sativa L.

    Science.gov (United States)

    Ghnaya, Tahar; Mnassri, Majda; Ghabriche, Rim; Wali, Mariem; Poschenrieder, Charlotte; Lutts, Stanley; Abdelly, Chedly

    2015-01-01

    Besides their role in nitrogen supply to the host plants as a result of symbiotic N fixation, the association between legumes and Rhizobium could be useful for the rehabilitation of metal-contaminated soils by phytoextraction. A major limitation presents the metal-sensitivity of the bacterial strains. The aim of this work was to explore the usefulness of Sinorhizobium meliloti originated from a mining site for Cd phytoextraction by Medicago sativa. Inoculated and non-inoculated plants were cultivated for 60 d on soils containing 50 and/or 100 mg Cd kg−1 soil. The inoculation hindered the occurrence of Cd- induced toxicity symptoms that appeared in the shoots of non-inoculated plants. This positive effect of S. meliloti colonization was accompanied by an increase in biomass production and improved nutrient acquisition comparatively to non-inoculated plants. Nodulation enhanced Cd absorption by the roots and Cd translocation to the shoots. The increase of plant biomass concomitantly with the increase of Cd shoot concentration in inoculated plants led to higher potential of Cd-phytoextraction in these plants. In the presence of 50 mg Cd kg−1 in the soil, the amounts of Cd extracted in the shoots were 58 and 178 μg plant−1 in non-inoculated and inoculated plants, respectively. This study demonstrates that this association M. sativa-S. meliloti may be an efficient biological system to extract Cd from contaminated soils. PMID:26528320

  16. Crossbreeding of Melilotoides ruthenicus and Medicago sativa%扁蓿豆与紫花苜蓿杂交育种研究

    Institute of Scientific and Technical Information of China (English)

    王殿魁; 李红; 罗新义

    2008-01-01

    受辐射突变育种理论的启示.辐射二倍体扁蓿豆(Melissutus ruthenicus)和四倍体苜蓿(Medicago sativa)种子,提高属间远缘杂交不育的意和性,获得成功后经过品比试验,区域试验和生产试验,最终育成正反交两个异源四倍体苜蓿新品种(1976~1992),即龙牧801苜蓿(Melilotoides ruthenicus(L.)Sojak×Medicago sativa L.cv.Longmu No.801)和龙牧803苜蓿(Medicago sativa L.XMelilotoides ruthenicus(L.)Sojok cv.Longmu No.803),并于1992年经全国牧草品种审定委员会审定登记.其中801苜蓿抗寒(-35℃~-45℃)、耐盐碱性(pH 8.16)较强,再生性好,在松嫩、三江平原地区每年刈割2次,干草产量6000~8000 kg/hm2;803苜蓿抗寒(-35℃~-45℃)、耐盐碱性(pH 8.16~8.4)较强、再生性好、丰产性好,在松辽平原和东部白浆土均可种植,每年刈割2-3次,干草产量10000~12000 kg/hm2.现将辐射处理后,突变体认定、杂交、杂种识别和育种方法及其过程加以论述.旨在和同行进行交流探讨,以期为苜蓿育种工作的发展有所裨益.

  17. Effect of salinity on some growth indices and total protein content of alfalfa genotypes inoculated with Sinorhizobium meliloti strains under greenhouse conditions

    OpenAIRE

    A. Fazaeli; H. Besharati

    2012-01-01

    This greenhouse experiment was carried out to evaluate the effects of salinity and bacterial inoculation on some growth indices and total protein content of alfalfa (Medicago sativa) using a factorial completely randomized design with three replications. The effect of three salinity levels (0, 6 and 12 dS/m) induced by a mixture of NaCl, CaCl2 and MgCl2 salts on growth indices and protein content of three alfalfa genotypes (Hamadani, Gharahyonjeh and Gharghalogh) at three levels of inoculatio...

  18. Proteomics analysis of alfalfa response to heat stress.

    Directory of Open Access Journals (Sweden)

    Weimin Li

    Full Text Available The proteome responses to heat stress have not been well understood. In this study, alfalfa (Medicago sativa L. cv. Huaiyin seedlings were exposed to 25 °C (control and 40 °C (heat stress in growth chambers, and leaves were collected at 24, 48 and 72 h after treatment, respectively. The morphological, physiological and proteomic processes were negatively affected under heat stress. Proteins were extracted and separated by two-dimensional polyacrylamide gel electrophoresis (2-DE, and differentially expressed protein spots were identified by mass spectrometry (MS. Totally, 81 differentially expressed proteins were identified successfully by MALDI-TOF/TOF. These proteins were categorized into nine classes: including metabolism, energy, protein synthesis, protein destination/storage, transporters, intracellular traffic, cell structure, signal transduction and disease/defence. Five proteins were further analyzed for mRNA levels. The results of the proteomics analyses provide a better understanding of the molecular basis of heat-stress responses in alfalfa.

  19. Effects of Growth Years on the Yield of Medicago sativa L.and Soil Nutrient%不同生长年限对紫花苜蓿产量及土壤养分的影响

    Institute of Scientific and Technical Information of China (English)

    陈志怡; 李金月

    2015-01-01

    The number of growth years (2, 5, 6, 7 and 10 years) of the yield and soil nutrient of Medicago sativa were measured. The results showed that the yield of Medicago sativa were first increased and then decreased with the increase of growth years which the 7 growth years of the yield of Medicago sativa was the highest, and the 7 growth years of the yield was significant higher than other growth years of Medicago sativa (P10 years>6 years>5 years>2 years. It also showed that the number of growth years of rangeability of soil nitrogen and potassium were larger, and soil total phosphorus and available phosphorus had no significant difference (P>0.05) of the number of growth years of Medicago sativa. The soil nutrient of the number of growth years of Medicago sativa decreased with the increase of soil depth which were mainly concentrated in the 0-20 cm depth and showed the“surface accumulation”. Correlation analysis showed that the soil nutrient and effective nutrient were extremely significant positive correlation with moisture content (P10年生>6年生>5年生>2年生,各生长年限紫花苜蓿土壤氮素和钾素变化幅度较大,土壤全磷和有效磷含量差异并不显著(P>0.05);垂直方向随着土层深度的增加,各生长年限紫花苜蓿土壤养分呈降低趋势,表现出明显的“表聚性”,并且各生长年限紫花苜蓿土壤养分储存于0~20 cm土层。相关性分析表明,紫花苜蓿土壤养分与相应的有效养分和含水量呈极显著正相关(P<0.01),与电导率和pH呈极显著的负相关(P<0.01),而pH和电导率之间极显著正相关(P<0.01),由此可见,生长年限对紫花苜蓿土壤养分的影响是土壤理化等因子的共同作用结果。

  20. NaCl effect on the distribution of wall ingrowth polymers and arabinogalactan proteins in type A transfer cells of Medicago sativa Gabès leaves.

    Science.gov (United States)

    Boughanmi, Néziha; Thibault, Florence; Decou, Raphael; Fleurat-Lessard, Pierrette; Béré, Emile; Costa, Guy; Lhernould, Sabine

    2010-06-01

    We studied the distribution of wall ingrowth (WI) polymers by probing thin sections of companion cells specialized as transfer cells in minor veins of Medicago sativa cv Gabès blade with affinity probes and antibodies specific to polysaccharides and glycoproteins. The wall polymers in the controls were similar in WIs and in the primary wall but differently distributed. The extent of labeling in these papillate WIs differed for JIM5 and JIM7 homogalacturonans but was in the same range for LM5 and LM6 rhamnogalacturonans and xyloglucans. These data show that WI enhancement probably requires arabinogalactan proteins (JIM8) mainly localized on the outer part of the primary wall and WIs. By comparison, NaCl-treated plants exhibited cell wall polysaccharide modifications indicating (1) an increase in unesterified homogalacturonans (JIM5), probably implicated in Na(+) binding and/or polysaccharide network interaction for limiting turgor variations in mesophyll cells; (2) enhancement of the xyloglucan network with an accumulation of fucosylated xyloglucans (CCRC-M1) known to increase the capacity of cellulose binding; and (3) specific recognition of JIM8 arabinogalactan proteins that could participate in both wall enlargement and cohesion by increasing the number of molecular interactions with the other polymers. In conclusion, the cell wall polysaccharide distribution in enlarged WIs might (1) participate in wall resistance to sequestration of Na(+), allowing a better control of hydric homeostasis in mesophyll cells to maintain metabolic activity in source leaves, and (2) maintain tolerance of M. sativa to NaCl.

  1. Study on Species and Distribution of Chemical Constituents from Medicago Sativa in China%国产苜蓿种类与分布及化学成分的研究

    Institute of Scientific and Technical Information of China (English)

    赵海福; 赵强

    2013-01-01

    The paper made a conclusion on the species and distribution of Medicago sativa in China according to wild species,local varieties,cultivars,introduced species and varieties of annual.At the same time,it discussed chemical constituents and medical value of Medicago sativa,and made a forecast of its industrial development and application prospect.%本文按照野生种、地方品种、育成品种、引进品种和一年生品种,对我国苜蓿的种类及分布,以及其含有的化学成分和药用价值进行讨论,并就苜蓿的产业发展和应用研究前景做出了展望.

  2. A sequence-based genetic map of Medicago truncatula and comparison of marker colinearity with M. sativa

    NARCIS (Netherlands)

    Choi, H.K.; Kim, D.; Uhm, T.; Limpens, E.H.M.; Lim, H.; Mun, J.H.; Kalo, P.; Penmetsa, R.V.; Seres, A.; Kulikova, O.; Roe, B.A.; Bisseling, T.; Kiss, G.B.; Cook, D.R.

    2004-01-01

    A core genetic map of the legume Medicago truncatula has been established by analyzing the segregation of 288 sequence-characterized genetic markers in an E, population composed of 93 individuals. These molecular markers correspond to 141 ESTs, 80 BAC end sequence tags, and 67 resistance gene analog

  3. MTGD: The Medicago truncatula genome database.

    Science.gov (United States)

    Krishnakumar, Vivek; Kim, Maria; Rosen, Benjamin D; Karamycheva, Svetlana; Bidwell, Shelby L; Tang, Haibao; Town, Christopher D

    2015-01-01

    Medicago truncatula, a close relative of alfalfa (Medicago sativa), is a model legume used for studying symbiotic nitrogen fixation, mycorrhizal interactions and legume genomics. J. Craig Venter Institute (JCVI; formerly TIGR) has been involved in M. truncatula genome sequencing and annotation since 2002 and has maintained a web-based resource providing data to the community for this entire period. The website (http://www.MedicagoGenome.org) has seen major updates in the past year, where it currently hosts the latest version of the genome (Mt4.0), associated data and legacy project information, presented to users via a rich set of open-source tools. A JBrowse-based genome browser interface exposes tracks for visualization. Mutant gene symbols originally assembled and curated by the Frugoli lab are now hosted at JCVI and tie into our community annotation interface, Medicago EuCAP (to be integrated soon with our implementation of WebApollo). Literature pertinent to M. truncatula is indexed and made searchable via the Textpresso search engine. The site also implements MedicMine, an instance of InterMine that offers interconnectivity with other plant 'mines' such as ThaleMine and PhytoMine, and other model organism databases (MODs). In addition to these new features, we continue to provide keyword- and locus identifier-based searches served via a Chado-backed Tripal Instance, a BLAST search interface and bulk downloads of data sets from the iPlant Data Store (iDS). Finally, we maintain an E-mail helpdesk, facilitated by a JIRA issue tracking system, where we receive and respond to questions about the website and requests for specific data sets from the community.

  4. 甘农3号紫花苜蓿种子生产栽培技术规程%Regulations on cultivation techniques of Gannong No.3 Medicago sativa.L for seed production

    Institute of Scientific and Technical Information of China (English)

    杜文华; 田新会; 曹致中

    2006-01-01

    论述了甘农3号紫花苜蓿Medicago sativa var.Gannong No.3从品种选择到地块选择、田间管理等一系列种子生产栽培技术规程,对甘农3号紫花苜蓿种子生产具有一定指导意义.

  5. Investigation of Antileishmanial Effect of Alcoholic Extract and Essential Oil of Medicinal Plant Leaf Black Alfalfa (Medicago Lupulina, on The Number of Clinical Isolates of Leishmania Major Promastigotes in Vitro

    Directory of Open Access Journals (Sweden)

    E Gharirvand Eskandari

    2016-05-01

    Full Text Available Introduction: Leishmaniasis has created enormous global health problems. Side effects, drug resistance and the lack of effective vaccines had led to the new effective compounds effective of plants. The aim of this study was to introduce a traditional medicinal plant called Black alfalfa (Medicago Lupulina that can be used as a valuable resource against cutaneous leishmaniasis. Methods: In this experimental study, alcoholic extract was prepared by maceration and essential oil by distillation water method. Leishmania major promastigotes were cultured at 25 ± 2° C in N.N.N culturemedium, then in Schneider and next were cultured in RPMI- 1640. afterward, using MTT (Methyl Thiazole Tetrazolium, the IC50 (Inhibitory Concentrations 50% for extracts, essence and Glucantime were determined. The results using Tukey and t-test were analyzed and were presented by software SPSS16. MTT assay were repeated. 3 times for each sample. Results: IC50 for alfalfa leaf extract and essential oil of black alfalfa and Glucantime against L. major promastigotes was determined after 24, 48 and 72 hours, 240, 130 and 69 micrograms per ml, and 801, 340 and 190 micrograms per ml, also 26, 19 and 11 micrograms per ml , respectively. There was a significant differences between the IC50 plant extract and essential oil and Glucantime after 24, 48 and 72 hours. Conclusion: Alcoholic extracts and essential oil the plant had significant anti leishmaniasis effects in vitro. In this way, it can be considered as an anti-leishmaniasis among the herbs.

  6. Alfalfa variety selection for maximum fiber content, protein and nitrogen fixation

    Energy Technology Data Exchange (ETDEWEB)

    Ruhland, Christopher T. [Minnesota State Univ., Mankato, MN (United States); Knox, John [Minnesota State Univ., Mankato, MN (United States); Ward, Susan [Minnesota State Univ., Mankato, MN (United States); Agarwal, V. J. [Minnesota State Univ., Mankato, MN (United States); Frey, John [Minnesota State Univ., Mankato, MN (United States); Carrow, Duane [Minnesota State Univ., Mankato, MN (United States); Jones, Bruce [Minnesota State Univ., Mankato, MN (United States); Rife, James [Minnesota State Univ., Mankato, MN (United States)

    2012-09-01

    The fertile soils of Southern Minnesota are highly productive from both a natural and agricultural standpoint. We chose to examine potential feedstock in both of these settings as a focus for our study. In part one of this report we detail our findings examining potential feedstock in prairie and wetlands in the Mankato, MN area in 2009. We were able to familiarize ourselves with techniques used to isolate and quantify concentrations of cellulose, hemicellulose and lignin in both a classroom and laboratory setting. These techniques were then used for our experiments that examined the effects of harvest regime, irrigation and salinity on eight potential-feedstock varieties of alfalfa (Medicago sativa).

  7. Comparación de dos índices cuantitativos de estimación del estado de desarrollo de la alfalfa Comparison of two quantitative indexes for the estimation of alfalfa development stages

    Directory of Open Access Journals (Sweden)

    M.L. Bernáldez

    2006-12-01

    Full Text Available El estado de desarrollo de la alfalfa (Medicago sativa L. es una variable de estudio común en evaluaciones de cultivares, dada su relación con la composición química y la tasa de crecimiento de la pastura. La determinación de los índices cuantitativos "estado medio por conteo" y "estado medio por peso" (EMC y EMP respectivamente permite la descripción del estado de desarrollo en pasturas de alfalfa de una manera objetiva y reproducible. Los índices EMC y EMP describen igualmente el estado de desarrollo de la alfalfa cuando la pastura se encuentra próxima al momento de utilización recomendado en la práctica. La ventaja de estimar EMC en relación a EMP, se basa en la rapidez operativa que ofrece la generación de datos para el cálculo del primero.The developmental stage of alfalfa (Medicago sativa L. is an usual variable of study when evaluating cultivars because of its relationship with chemical composition and pasture growth rate. Determination of quantitative indexes such as "mean stage by count" and "mean stage by weight" (MSC and MSW respectively makes it possible to describe the developmental phenological stages of alfalfa pastures in a more objective and reproducible way. Likewise, both the MSC and MSW indexes, describe the developmental stages of alfalfa when the pasture is close to the recommended utilisation time in practice. The advantage of estimating MSC in relation to MSW is based on the higher operative efficiency offered by the former in data generation for its calculation.

  8. Lignin modification leads to increased nodule numbers in alfalfa.

    Science.gov (United States)

    Gallego-Giraldo, Lina; Bhattarai, Kishor; Pislariu, Catalina I; Nakashima, Jin; Jikumaru, Yusuke; Kamiya, Yuji; Udvardi, Michael K; Monteros, Maria J; Dixon, Richard A

    2014-03-01

    Reduction of lignin levels in the forage legume alfalfa (Medicago sativa) by down-regulation of the monolignol biosynthetic enzyme hydroxycinnamoyl coenzyme A:shikimate hydroxycinnamoyl transferase (HCT) results in strongly increased digestibility and processing ability of lignocellulose. However, these modifications are often also associated with dwarfing and other changes in plant growth. Given the importance of nitrogen fixation for legume growth, we evaluated the impact of constitutively targeted lignin modification on the belowground organs (roots and nodules) of alfalfa plants. HCT down-regulated alfalfa plants exhibit a striking reduction in root growth accompanied by an unexpected increase in nodule numbers when grown in the greenhouse or in the field. This phenotype is associated with increased levels of gibberellins and certain flavonoid compounds in roots. Although HCT down-regulation reduced biomass yields in both the greenhouse and field experiments, the impact on the allocation of nitrogen to shoots or roots was minimal. It is unlikely, therefore, that the altered growth phenotype of reduced-lignin alfalfa is a direct result of changes in nodulation or nitrogen fixation efficiency. Furthermore, HCT down-regulation has no measurable effect on carbon allocation to roots in either greenhouse or 3-year field trials.

  9. The photosynthetic and stomatal response of Medicago sativa cv. saranac to free-air CO{sub 2} enrichment (F.A.C.E.) and nitrogen

    Energy Technology Data Exchange (ETDEWEB)

    Bridson, N.P.

    1996-08-01

    Plots of Medicago sativa cv. saranac were grown in the field at ambient (355 {mu}mol CO{sub 2} mol{sup -1} air) or elevated (600{mu}mol CO{sub 2} mol{sup -1} air) CO{sub 2} concentrations. High (200kg yr{sup -1}) or low (20kg yr{sup -1}) nitrogen levels were applied to two isogeneic lines, one able and one unable to use nitrogen fixing bacteria. Plants were in the second year of field growth. Exposure to elevated CO{sub 2} was via a Free-Air CO{sub 2} Enrichment System (FACE). Elevated CO{sub 2} increased diurnal assimilation by between 12% and 92%. Analysis of A/C{sub i} responses showed that effective nitrogen fertilisation was more important to rubisCO and RuBP activity than elevated CO{sub 2}. No acclimation was consistently observed. Leaves lower down the canopy were found to have lower Vc{sub max} and J{sub max} values, though age may be the cause of the latter effect. FACE conditions have only a small effect on these responses. There was some evidence found for the down-regulation of photosynthesis in the late afternoon. The FACE conditions had no affect on stomatal density but did increase epidermal cell density.

  10. Assessing quality of Medicago sativa silage by monitoring bacterial composition with single molecule, real-time sequencing technology and various physiological parameters.

    Science.gov (United States)

    Bao, Weichen; Mi, Zhihui; Xu, Haiyan; Zheng, Yi; Kwok, Lai Yu; Zhang, Heping; Zhang, Wenyi

    2016-06-24

    The present study applied the PacBio single molecule, real-time sequencing technology (SMRT) in evaluating the quality of silage production. Specifically, we produced four types of Medicago sativa silages by using four different lactic acid bacteria-based additives (AD-I, AD-II, AD-III and AD-IV). We monitored the changes in pH, organic acids (including butyric acid, the ratio of acetic acid/lactic acid, γ-aminobutyric acid, 4-hyroxy benzoic acid and phenyl lactic acid), mycotoxins, and bacterial microbiota during silage fermentation. Our results showed that the use of the additives was beneficial to the silage fermentation by enhancing a general pH and mycotoxin reduction, while increasing the organic acids content. By SMRT analysis of the microbial composition in eight silage samples, we found that the bacterial species number and relative abundances shifted apparently after fermentation. Such changes were specific to the LAB species in the additives. Particularly, Bacillus megaterium was the initial dominant species in the raw materials; and after the fermentation process, Pediococcus acidilactici and Lactobacillus plantarum became the most prevalent species, both of which were intrinsically present in the LAB additives. Our data have demonstrated that the SMRT sequencing platform is applicable in assessing the quality of silage.

  11. Effect of lead treatment on medicarpin accumulation and on the gene expression of key enzymes involved in medicarpin biosynthesis in Medicago sativa L.

    Science.gov (United States)

    Ghelich, Sima; Zarinkamar, Fatemeh; Soltani, Bahram Mohammad; Niknam, Vahid

    2014-12-01

    Lead (Pb) is the most common heavy metal contaminant in the environment. The present study was undertaken to determine the effect of Pb treatment on medicarpin production and accumulation in Medicago sativa L. To this aim, 7- and 30-day-old plants were treated with 0, 120, 240, 500, and 1,000 μM Pb during 10 days. The content of medicarpin was determined by HPLC, and the extent of medicarpin production was deduced from the result of semiquantitative RT-PCR performed on PAL, CHS, and VR genes. HPLC results indicated that medicarpin concentration has been reduced in the roots, while its exudation to the culture medium has been increased. RT-PCR results indicated that the transcript levels of PAL, CHS, and VR genes have not been affected following Pb stress in seedlings. At the vegetative stage, transcript levels of PAL and CHS genes have been reduced in the roots. However, the transcript level of VR gene increased at 120 and 240 μM Pb, while it decreased at higher concentrations. In the shoot, the transcript levels of PAL, CHS, and VR genes were increased following increased concentration of lead in the medium. Overall, q-PCR results suggest that medicarpin biosynthesis has been induced in the shoots and reduced in the roots of the plants treated with a toxic concentration of Pb.

  12. Effect of application rate of commercial lignite-derived amendments on early-stage growth of Medicago sativa and soil health, in acidic soil conditions

    Science.gov (United States)

    Patti, Antonio; Little, Karen; Rose, Michael; Jackson, Roy; Cavagnaro, Tim

    2013-04-01

    Commercially available lignite-derived amendments, sold mainly as humate preparations, have been promoted as plant growth stimulants leading to higher crop yields. These products are also claimed to improve soil properties such as pH. This study investigated the effect of application rate of three lignite-derived amendments on the early-stage growth of a pasture legume, lucerne (Medicago sativa), and soil health in a soil type common to south eastern Australia, in a glasshouse setting. An organic-mineral humate product and 'run of mine' lignite coal did not improve shoot or root growth despite application at a range of rates at, and in excess of, the manufacturers recommendation. Application of soluble K-humate product at 20 kg/ha (9.5 kg/ha C equivalent) produced an observable positive effect in shoot growth. At this application rate, a significant delay in the appearance of chlorotic symptoms was observed along with an increase in soil pH concurrent with decreased availability of soil Mn and Al. Higher root dry weight was associated with lower microbial biomass carbon which may indicate an effect on allocation of resources between the microbial community and the plant. An assessment of the effectiveness of lignite-derived amendments on plant growth, as well as their potential to improve the health of an acidic soil will assist farmers in making decisions regarding the use of these products.

  13. A vapBC-type toxin-antitoxin module of Sinorhizobium meliloti influences symbiotic efficiency and nodule senescence of Medicago sativa.

    Science.gov (United States)

    Lipuma, Justine; Cinege, Gyöngyi; Bodogai, Monica; Oláh, Boglárka; Kiers, Aurélie; Endre, Gabriella; Dupont, Laurence; Dusha, Ilona

    2014-12-01

    The symbiotic nitrogen-fixing soil bacterium Sinorhizobium meliloti carries a large number of toxin-antitoxin (TA) modules both on the chromosome and megaplasmids. One of them, the vapBC-5 module that belongs to the type II systems was characterized here. It encodes an active toxin vapC-5, and was shown to be controlled negatively by the complex of its own proteins. Different mutants of the vapBC-5 genes exhibited diverse effects on symbiotic efficiency during interaction with the host plant Medicago sativa. The absence of the entire vapBC-5 region had no influence on nodule formation and nitrogen fixation properties. The strain carrying an insertion in the antitoxin gene showed a reduced nitrogen fixation capacity resulting in a lower plant yield. In contrast, when the toxin gene was mutated, the strain developed more efficient symbiosis with the host plant. The nitrogen fixing root nodules had a delayed senescent phenotype and contained elevated level of plant-derived molecules characteristic of later steps of nodule development. The longer bacteroid viability and abundance of active nitrogen fixing zone resulted in increased production of plant material. These data indicate that modification of the toxin/antitoxin production may influence bacteroid metabolism and may have an impact on the adaptation to changing environmental conditions.

  14. Assessing quality of Medicago sativa silage by monitoring bacterial composition with single molecule, real-time sequencing technology and various physiological parameters

    Science.gov (United States)

    Bao, Weichen; Mi, Zhihui; Xu, Haiyan; Zheng, Yi; Kwok, Lai Yu; Zhang, Heping; Zhang, Wenyi

    2016-01-01

    The present study applied the PacBio single molecule, real-time sequencing technology (SMRT) in evaluating the quality of silage production. Specifically, we produced four types of Medicago sativa silages by using four different lactic acid bacteria-based additives (AD-I, AD-II, AD-III and AD-IV). We monitored the changes in pH, organic acids (including butyric acid, the ratio of acetic acid/lactic acid, γ-aminobutyric acid, 4-hyroxy benzoic acid and phenyl lactic acid), mycotoxins, and bacterial microbiota during silage fermentation. Our results showed that the use of the additives was beneficial to the silage fermentation by enhancing a general pH and mycotoxin reduction, while increasing the organic acids content. By SMRT analysis of the microbial composition in eight silage samples, we found that the bacterial species number and relative abundances shifted apparently after fermentation. Such changes were specific to the LAB species in the additives. Particularly, Bacillus megaterium was the initial dominant species in the raw materials; and after the fermentation process, Pediococcus acidilactici and Lactobacillus plantarum became the most prevalent species, both of which were intrinsically present in the LAB additives. Our data have demonstrated that the SMRT sequencing platform is applicable in assessing the quality of silage. PMID:27340760

  15. PENINGKATAN PRODUKSI DAN KECERNAAN BAHAN KERING ALFALFA DENGAN PEMUPUKAN FOSFAT

    Directory of Open Access Journals (Sweden)

    - Sunarni

    2014-06-01

    Full Text Available Alfalfa (Medicago    sativa    L. as one of legume forage crops for ruminant livestock is very sensitive to the phosphorus deficiency. Phosphorus fertilizers have been used widely to overcome those problem. However, the high cost of superphosphate (SP is now focusing attention on cheaper rock phosphate (RP fertilizer. A field experiment was conducted on a latosolic soil (low pH, and low available Bray II extractable P. The objective of the research is to evaluate the effect of phosphorus fertilizer from difference sources on dry matter production, and in    vitro dry matter digestibility of alfalfa. Completely randomized block design with 7 treatments in 3 replicates was used in this field experiment. The treatments were T0 (control, T1 (SP, 100 kg P2O5/ha, T2 (SP, 200 kg P2O5/ha, T3 (SP, 300 kg P2O5/ha, T4 (RP, 100 kg P2O5/ha, T5 (RP, 200 kg P2O5/ha, T6 (RP, 300 kg P2O5/ha. Size of each plot was 2 m x 2 m, and fertilized with P fertilizer (SP, RP according to the assigned treatment. All plot received basal fertilizer of urea (50 kg N/ha, KCl (100 kg K2O/ha and poultry manure (2 ton/ha. Medicago    sativa was defoliated on 12 weeks after planting and analyzed for dry matter (DM production and in    vitro DM digestibility. Result showed that DM production significantly influenced by the treatments. Superphosphate fertilization resulted DM production significantly higher compared to control and RP, except on RP 300 kg P2O5/ha was non-significant difference. In    vitro dry matter digestibility (IVDMD of alfalfa was not affected by the treatment. There was non-significant difference in IVDMD between the treatments. Therefore, RP (300 kg P2O5/ha could replace SP to increased DM production and not affected for IVDMD of Medicago    sativa in acid latosolic soil.

  16. [Efficiency of alfalfa and reed in the phytoremediation of hydrocarbon polluted soil].

    Science.gov (United States)

    Muratova, A Iu; Turkovskaia, O V; Hubner, T; Kuschk, P

    2003-01-01

    The efficacy of plants as means of decontaminating hydrocarbon-polluted soil has been studied. Ditch reed (Phragmites australis) and alfalfa (Medicago sativa) markedly intensified processes of pollutant destruction, the effect being particularly pronounced in the case of polycyclic aromatic hydrocarbons (PAHs). Comparative analysis of microflora in soils (including those devoid of plants and rhizosphere) demonstrated that, in addition to preventing the pollutant-induced decrease in the amount of heterotrophic microorganisms, the plants stimulated their development, significantly increasing the population of destructors. Effects of plants on major physiological groups of soil microorganisms under conditions of pollution were ambiguous. The rhizosphere consortium of alfalfa was less susceptible to effects of pollutants than that of reed.

  17. Genetic diversity of alfalfa domesticated varietal populations from Libyan genbank revealed by RAPD markers

    Directory of Open Access Journals (Sweden)

    Ahsyee Salem R.

    2013-01-01

    Full Text Available Alfalfa (Medicago sativa L. is an important forage legume in Libya. The genetic diversity of nine alfalfa domesticated varietal populations was studied using thirteen RAPD primer combinations. The number of polymorphic fragments detected per primer combination ranged from 8 to 46 bands with an average of 24 bands. The number of polymorphic bands detected was from 6 (Atalia population to 37 (Gabsia population. The lowest genetic distance was 0.058 and the highest was 0.655. The average genetic distance was (0.356. The dendrogram based on Ward’s minimum variance clustering method grouped the nine populations into the two main clusters. The first group included Fazania, Atalia, Masratia, Zawia, Denamo Ferade and Arezona. The second group was composed of Tagoria, Gabsia and Wade Alrabeh. The simplicity of RAPD assays for detection of genetic polymorphisms is confirmed in our study, and results can be utilized in breeding practice.

  18. Alfalfa nutritive quality for ruminant livestock as influenced by ambient air quality in west-central Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Lin, J.C. [Department of Animal Sciences, Auburn University, Auburn, AL 36849 (United States); Nosal, M. [Department of Mathematics and Statistics, University of Calgary, Calgary, AB T2N 1N4 (Canada); Muntifering, R.B. [Department of Animal Sciences, Auburn University, Auburn, AL 36849 (United States)]. E-mail: muntirb@auburn.edu; Krupa, S.V. [Department of Plant Pathology, University of Minnesota, St. Paul, MN 55108 (United States)

    2007-09-15

    Alfalfa (Medicago sativa) nutritive quality response to ambient ozone (O{sub 3}), sulfur dioxide (SO{sub 2}) and oxides of nitrogen (NO {sub x} ) were assessed at three locations in west-central Alberta, Canada (1998-2002). Yield data were segregated into high and low relative to overall median yield. Ozone concentrations (hourly median and 95th-percentile) and precipitation (P) contributed 69 and 29%, respectively, to the variability in crude protein (CP) concentration in low-yielding alfalfa, whereas mean temperature (T) and relative humidity (RH) collectively influenced 98% of the variation in CP in high-yielding alfalfa. Three-fourths of the accounted variation in relative feed value (RFV) of low-yielding alfalfa was attributable to P, T and RH, whereas median and 95th-percentile hourly O{sub 3} concentrations and SO{sub 2} and NO {sub x} exposure integrals contributed 25%. In contrast, air quality, (mainly O{sub 3}) influenced 86% of the accounted variation in RFV of high-yielding alfalfa, and T and P collectively contributed 14%. - Exposure to ambient concentrations of phytotoxic air pollutants affected nutritive quality of alfalfa for ruminant livestock in a yield-dependent manner.

  19. Preliminary Study on Effect of Herbicides on Alfalfa Yield and Weed Community Characteristics in Yellow River Delta, China

    Directory of Open Access Journals (Sweden)

    WANG Guo-liang

    2016-05-01

    Full Text Available Alfalfa(Medicago sativa is one of important legume forages worldwide. However, weed is the main factor limiting alfalfa production. Biomass quality and yield and stability of dry matter production during cultivation are directly associated with the interference of weeds which compete with alfalfa for water, light and nutrients. The use of herbicides is a good alternative for weed control. In order to control weed in alfalfa field with suitable herbicide in Yellow River delta, the effect of four herbicides(imazethapyr, quizalofop-p-ethyl, haloxyfop-r-methyl and oxyfluorfen with different concentration on afalfal yield and weed community characteristics were studied. The results showed that both imazethapyr and haloxyfop-r-methyl treatments could increase alfalfa yield, and the best herbicide application concentration was imazethapyr with 2 000 mL·hm-2 and haloxyfop-r-methyl with 700 mL·hm-2, but oxyfluorfen treatment would limit alfalfa growth significantly. Weed species numbers in the treatments of imazethapyr, quizalofop-p-ethyl and oxyfluorfen decreased significantly. Digitariasanguinalis, Portulacaoleracea and Echinochloacrusgalli were more difficult to control from specie important value in all treatments. Species diversity index decreased with higher herbicide concentration in all treatments. From this study, herbicide imazethapyr with 2 000 mL·hm-2 application concentration was the best weed control method, and the second one was haloxyfop-r-methyl with 700 mL·hm-2 application concentration.

  20. The fermentation quality of mixed silage of Medicago sativa and Roegneria turczaninovii%苜蓿与直穗鹅观草混贮发酵品质研究

    Institute of Scientific and Technical Information of China (English)

    王林; 张慧杰; 玉柱; 徐春城; 孙启忠

    2011-01-01

    以苜蓿(Medicagosativa)与直穗鹅观草(Roegneria turczaninovi)为原料,按不同比例混贮,通过分析发酵品质和营养成分,优化混合青贮比例。结果表明,苜蓿青贮后干物质(DM)和中性洗涤纤维(NDF)含量增加,粗蛋白(CP)、酸性洗涤纤维(ADF)、可溶性碳水化合物(wSC)含量降低,直穗鹅观草青贮后DM、NDF、CP及ADF含量增加,粗脂肪(EE)和WSC降低;混贮处理CP和Ca含量显著高于直穗鹅观草单贮,而显著低于苜蓿单贮,DM、NDF、ADF含量显著低于直穗鹅观草单贮;随直穗鹅观草在混贮比例中的提高,pH值呈降低趋势,混贮中乳酸占总酸含量居于两种牧草单贮之间,苜蓿与直穗鹅观草3:7混贮乙酸含量占总酸含量显著高于其他处理(P〈0.05),为33.9%,混贮处理丁酸产生较少;苜蓿与直穗鹅观草混贮氨态氮占总氮含量显著低于苜蓿单贮(P〈0.05),且显著高于直穗鹅观草单贮(P〈0.05);青贮后各处理乳酸菌数达到10^6cfu/g(以鲜物质为基础),较青贮前提高,各混贮处理乳酸菌和霉菌数高于两种牧草单贮;直穗鹅现草单贮发酵品质评分为97分,且氨态氮含量较低,为最佳处理。%The different proportions of Medicago sativa and Roegneria turczaninovii were ensiled to opti- mize the proportion of mixed silage by measuring the nutrition constituent, which was used to estimate fermentation quality. The results of this study showed that the silage increased the content of DM and NDF and decreased the CP, ADF, WSC of alfalfa products, and that the silage increased the content of DM, NDF, CP and ADF, and decreased the EE and WSC of R. turczaninovii. The CP and Ca content of mixed silage was significantly higher than R. turczaninovii silage and lower than alfalfa silage, and the content of DM, NDF, ADF was significantly lower than R. turczaninovii silage. As the

  1. The Role of Proanthocyanidins Complex in Structure and Nutrition Interaction in Alfalfa Forage.

    Science.gov (United States)

    Jonker, Arjan; Yu, Peiqiang

    2016-05-23

    Alfalfa (Medicago sativa L.) is one of the main forages grown in the world. Alfalfa is a winter hardy, drought tolerant, N-fixing legume with a good longevity, high yield, high nutrient levels, high digestibility, unique structural to non-structural components ratio, high dry matter intake, and high animal productivity per hectare. However, its main limitation is its excessively rapid initial rate of protein degradation in the rumen, which results in pasture bloat and inefficient use of protein with consequent excessive excretions of nitrogen into the environment. Proanthocyanidins are secondary plant metabolites that can bind with protein and thereby reduce the rate and extent of ruminal protein degradation. However, these secondary metabolites do not accumulate in alfalfa. This review aims to firstly describe the events involved in the rapid release of protein from alfalfa and its effect on ruminant nutrition, environmental pollution, and pasture bloat; secondly, to describe occurrence, structure, functions and benefits of moderate amounts of proanthocyanidin; and finally, to describe the development of alfalfa which accumulates moderate amounts of proanthocyanidins. The emphasis of this review focuses on the role of proanthocyanidins compounds in structure and nutrition interaction in ruminant livestock systems.

  2. The Role of Proanthocyanidins Complex in Structure and Nutrition Interaction in Alfalfa Forage

    Directory of Open Access Journals (Sweden)

    Arjan Jonker

    2016-05-01

    Full Text Available Alfalfa (Medicago sativa L. is one of the main forages grown in the world. Alfalfa is a winter hardy, drought tolerant, N-fixing legume with a good longevity, high yield, high nutrient levels, high digestibility, unique structural to non-structural components ratio, high dry matter intake, and high animal productivity per hectare. However, its main limitation is its excessively rapid initial rate of protein degradation in the rumen, which results in pasture bloat and inefficient use of protein with consequent excessive excretions of nitrogen into the environment. Proanthocyanidins are secondary plant metabolites that can bind with protein and thereby reduce the rate and extent of ruminal protein degradation. However, these secondary metabolites do not accumulate in alfalfa. This review aims to firstly describe the events involved in the rapid release of protein from alfalfa and its effect on ruminant nutrition, environmental pollution, and pasture bloat; secondly, to describe occurrence, structure, functions and benefits of moderate amounts of proanthocyanidin; and finally, to describe the development of alfalfa which accumulates moderate amounts of proanthocyanidins. The emphasis of this review focuses on the role of proanthocyanidins compounds in structure and nutrition interaction in ruminant livestock systems.

  3. Transgenic alfalfa plants expressing the sweetpotato Orange gene exhibit enhanced abiotic stress tolerance.

    Directory of Open Access Journals (Sweden)

    Zhi Wang

    Full Text Available Alfalfa (Medicago sativa L., a perennial forage crop with high nutritional content, is widely distributed in various environments worldwide. We recently demonstrated that the sweetpotato Orange gene (IbOr is involved in increasing carotenoid accumulation and enhancing resistance to multiple abiotic stresses. In this study, in an effort to improve the nutritional quality and environmental stress tolerance of alfalfa, we transferred the IbOr gene into alfalfa (cv. Xinjiang Daye under the control of an oxidative stress-inducible peroxidase (SWPA2 promoter through Agrobacterium tumefaciens-mediated transformation. Among the 11 transgenic alfalfa lines (referred to as SOR plants, three lines (SOR2, SOR3, and SOR8 selected based on their IbOr transcript levels were examined for their tolerance to methyl viologen (MV-induced oxidative stress in a leaf disc assay. The SOR plants exhibited less damage in response to MV-mediated oxidative stress and salt stress than non-transgenic plants. The SOR plants also exhibited enhanced tolerance to drought stress, along with higher total carotenoid levels. The results suggest that SOR alfalfa plants would be useful as forage crops with improved nutritional value and increased tolerance to multiple abiotic stresses, which would enhance the development of sustainable agriculture on marginal lands.

  4. Genome-wide SNP discovery in tetraploid alfalfa using 454 sequencing and high resolution melting analysis

    Directory of Open Access Journals (Sweden)

    Zhao Patrick X

    2011-07-01

    Full Text Available Abstract Background Single nucleotide polymorphisms (SNPs are the most common type of sequence variation among plants and are often functionally important. We describe the use of 454 technology and high resolution melting analysis (HRM for high throughput SNP discovery in tetraploid alfalfa (Medicago sativa L., a species with high economic value but limited genomic resources. Results The alfalfa genotypes selected from M. sativa subsp. sativa var. 'Chilean' and M. sativa subsp. falcata var. 'Wisfal', which differ in water stress sensitivity, were used to prepare cDNA from tissue of clonally-propagated plants grown under either well-watered or water-stressed conditions, and then pooled for 454 sequencing. Based on 125.2 Mb of raw sequence, a total of 54,216 unique sequences were obtained including 24,144 tentative consensus (TCs sequences and 30,072 singletons, ranging from 100 bp to 6,662 bp in length, with an average length of 541 bp. We identified 40,661 candidate SNPs distributed throughout the genome. A sample of candidate SNPs were evaluated and validated using high resolution melting (HRM analysis. A total of 3,491 TCs harboring 20,270 candidate SNPs were located on the M. truncatula (MT 3.5.1 chromosomes. Gene Ontology assignments indicate that sequences obtained cover a broad range of GO categories. Conclusions We describe an efficient method to identify thousands of SNPs distributed throughout the alfalfa genome covering a broad range of GO categories. Validated SNPs represent valuable molecular marker resources that can be used to enhance marker density in linkage maps, identify potential factors involved in heterosis and genetic variation, and as tools for association mapping and genomic selection in alfalfa.

  5. Transcript profiling of two alfalfa genotypes with contrasting cell wall composition in stems using a cross-species platform: optimizing analysis by masking biased probes

    Directory of Open Access Journals (Sweden)

    Jung Hans-Joachim G

    2010-05-01

    Full Text Available Abstract Background The GeneChip® Medicago Genome Array, developed for Medicago truncatula, is a suitable platform for transcript profiling in tetraploid alfalfa [Medicago sativa (L. subsp. sativa]. However, previous research involving cross-species hybridization (CSH has shown that sequence variation between two species can bias transcript profiling by decreasing sensitivity (number of expressed genes detected and the accuracy of measuring fold-differences in gene expression. Results Transcript profiling using the Medicago GeneChip® was conducted with elongating stem (ES and post-elongation stem (PES internodes from alfalfa genotypes 252 and 1283 that differ in stem cell wall concentrations of cellulose and lignin. A protocol was developed that masked probes targeting inter-species variable (ISV regions of alfalfa transcripts. A probe signal intensity threshold was selected that optimized both sensitivity and accuracy. After masking for both ISV regions and previously identified single-feature polymorphisms (SFPs, the number of differentially expressed genes between the two genotypes in both ES and PES internodes was approximately 2-fold greater than the number detected prior to masking. Regulatory genes, including transcription factor and receptor kinase genes that may play a role in development of secondary xylem, were significantly over-represented among genes up-regulated in 252 PES internodes compared to 1283 PES internodes. Several cell wall-related genes were also up-regulated in genotype 252 PES internodes. Real-time quantitative RT-PCR of differentially expressed regulatory and cell wall-related genes demonstrated increased sensitivity and accuracy after masking for both ISV regions and SFPs. Over 1,000 genes that were differentially expressed in ES and PES internodes of genotypes 252 and 1283 were mapped onto putative orthologous loci on M. truncatula chromosomes. Clustering simulation analysis of the differentially expressed genes

  6. Molecular cloning and characterization of the MsHSP17.7 gene from Medicago sativa L.

    Science.gov (United States)

    Li, Zhen-Yi; Long, Rui-Cai; Zhang, Tie-Jun; Yang, Qing-Chuan; Kang, Jun-Mei

    2016-08-01

    Heat shock proteins (HSPs) are ubiquitous protective proteins that play crucial roles in plant development and adaptation to stress, and the aim of this study is to characterize the HSP gene in alfalfa. Here we isolated a small heat shock protein gene (MsHSP17.7) from alfalfa by homology-based cloning. MsHSP17.7 contains a 477-bp open reading frame and encodes a protein of 17.70-kDa. The amino acid sequence shares high identity with MtHSP (93.98 %), PsHSP17.1 (83.13 %), GmHSP17.9 (74.10 %) and SlHSP17.6 (79.25 %). Phylogenetic analysis revealed that MsHSP17.7 belongs to the group of cytosolic class II small heat shock proteins (sHSP), and likely localizes to the cytoplasm. Quantitative RT-PCR indicated that MsHSP17.7 was induced by heat shock, high salinity, peroxide and drought stress. Prokaryotic expression indicated that the salt and peroxide tolerance of Escherichia coli was remarkably enhanced. Transgenic Arabidopsis plants overexpressing MsHSP17.7 exhibited increased root length of transgenic Arabidopsis lines under salt stress compared to the wild-type line. The malondialdehyde (MDA) levels in the transgenic lines were significantly lower than in wild-type, although proline levels were similar between transgenic and wild-type lines. MsHSP17.7 was induced by heat shock, high salinity, oxidative stress and drought stress. Overexpression analysis suggests that MsHSP17.7 might play a key role in response to high salinity stress.

  7. 低温胁迫对紫苜蓿 'W L525 ' 生理特性的影响%Effect of low temperature stress on physiological characteristics of Medicago sativa Linn.'WL525'

    Institute of Scientific and Technical Information of China (English)

    陈梓健; 刘凤民; 张伟丽

    2015-01-01

    Medicago sativa Linn.WL525 was treated by low temperature stress for 4 d and the content of MDA and soluble sugar, POD activity, and relative conductivity were measured.The results showed that under low temperature stress, the MDA content in leaves cells of Medicago sativa Linn.WL525 showed increasing trend;POD activity increased first and then decreased;the soluble sugar content and the rela-tive conductivity showed increasing trend.These four kind of physiological indexes related closely to the cold hardiness of Medicago sativa Linn.WL525.The increased content of soluble sugar and POD activity adjust the WL525 plant to the damage caused by temperature stress.%以紫苜蓿 (Medicago sativa Linn.) 'WL525' 为试验材料, 通过低温处理4 d, 就低温胁迫对紫苜蓿中丙二醛 (Malondialdehyde, MDA) 浓度、 相对电导率、 过氧化物酶 (Peroxidase, POD) 活性和可溶性糖质量浓度变化的影响进行了研究.结果表明: 随着低温胁迫时间的延长, 紫苜蓿 'WL525' 叶片细胞中的MDA浓度总体呈现升高的趋势, POD酶活性呈现出先增加后降低的趋势, 可溶性糖质量浓度和相对电导率均呈现出升高的趋势.4个生理指标均与紫苜蓿 'WL525' 的抗寒性有密切联系, 紫苜蓿 'WL525' 通过增加POD酶活性和可溶性糖的质量浓度来调节低温对其造成的伤害.

  8. 干旱地区紫花苜蓿光合日变化规律研究%Study on diurnal variation of photosynthesis for Medicago sativa in arid area

    Institute of Scientific and Technical Information of China (English)

    贾宏涛; 赵成义; 盛钰; 蒋平安; 孙军涛

    2009-01-01

    自然条件下,采用PP system公司生产的CIRAS光合作用仪,研究了干旱胁迫下新疆阜康地区一年生紫花苜蓿Medicago sativa的光合日变化规律.结果表明:1)苜蓿光合速率日变化曲线呈现双峰曲线,在北京时间14:00、15:00,苜蓿的净光合速率出现明显的"午休"现象;2)苜蓿的光合速率(Pn)日平均为15.60[μmol/(m2·s),CO2],12:00达到最高值21.1[μmol/(m2· s),CO2],21:00达到最低值1.16[μmol/(m2·s),CO2];3)逐步多元回归和通径分析表明,光合有效辐射、蒸腾速率和胞间CO2浓度是直接影响光合速率日变化的主要因子.%This paper used CIRAS photosynthesis device which was made by British PP system company, to study the diurnal variation of photosynthesis for Medicago sativa in the area of Fukang under natural conditions. The results showed that 1)The variation curve of Medicago sativa showed twopeaks curve, and at 14:00, 15:00 of Beijing time, the photosynthesis for Medicago sativa exhibited an obvious midday depression phenomena. 2) The photosynthetic rate (Pn) sativa was 15.60 [μmol/(m2·s),CO2] daily averagely, with the highest value of 21.10 [μmol/(m2·s),CO2] at 12:00, and minimum of 1.16 [μmol/(m2·s),CO2] at 21:00. 3) The analysis of stepwise multiple regression and path coefficient showed that the photosynthetic active radiation (PAR), transpiration rate (Tr) and intercellular CO2 concentration were the main direct factors which affected the diurnal variation of Pn.

  9. Responses to Zn and EDTA Chelating Agents on Photosynthesis Characteristics of Alfalfa Leaves%Zn 和 EDTA 对紫花苜蓿叶片光合特性的响应

    Institute of Scientific and Technical Information of China (English)

    代惠萍; 赵桦; 贾根良; 冯佰利

    2016-01-01

    In order to explore the effective avenue on improving alfalfa(Medicage sativa L.)resistant ability un-der zinc stress,pot experiments were used to study the effect of EDTA on zinc accumulation,photosynthetic pigment content and chlorophyll fluorescence under zinc stress in different alfalfa leaves of three cultivars Medicago sativa ssp.,Vitoria Alfalfa and Medicago sativa cv..The results of this study indicated that the zinc contents in three culti-var leaves were significantly higher than that in control group.Compared with zinc stress alone,the addition of ED-TA strikingly enhanced the zinc absorption in leaves.In comparison with different cultivars,photosynthetic pigment content in Medicago sativa ssp.was higher than that in control group.After EDTA treatment,the contents of chloro-phyll a,chlorophyll b,total chlorophyll and carotenoids were 12.7%,1 1 .8%,12.5%,14.8% of Medicago sativa ssp.respectively,which were remarkably higher than that in the other two cultivars.Fo,Fv,Fm and Fv /Fm levels were increased by 5.4%,14.9%,18.1 %,4.0% of Medicago sativa ssp.with the treatment of EDTA.Our research indicated that EDTA was able to promote the accumulation of photosynthetic pigment,reduce the dissipation of ex-cessive excitation energy,improve the transmission efficiency of photosynthetic electron,and minimize the damages to alfalfa leaves PSⅡ caused by zinc stress effectively,all of which coherently boosted resistance capability to zinc in Medicago sativa ssp.cultivar.As the results suggested,EDTA with the appropriate concentration at 10 μg could coefficient alleviate the damage of Zinc stress to Medicago sativa ssp.,reduce dissipation of excess excitation and improve photochemical electron transport efficiency and efficiently protect from PSⅡ damage,EDTA obviously pro-moted the Zinc resistance of Medicago sativa ssp.under Zinc stress.%为了探索提高紫花苜蓿的抗锌能力,以3个紫花苜蓿品种为试材,采用土培法,研究 Zn 胁迫(250

  10. Ameliorating Effects of Exogenous Ca2+ and Salicylic Acid on Alfalfa Seedlings under Salt Stress%外源Ca2+和水杨酸对苜蓿幼苗盐害的缓解效应

    Institute of Scientific and Technical Information of China (English)

    柳斌; 周万海; 师尚礼; 赵平

    2011-01-01

    The ameliorating effects of exogenous Ca2+ and salicylic acid (SA) on 3 cultivars seedlings of alfalfa (Medicago sativa L.cv.Gannong 3, Medicago sativa L.cv.Golden Empress and Medicago sativa L.cv.Xinjiang Daye) under salt stress (100 mM NaCl) were determined.The results showed that the exogenous Ca2+ and SA can alleviate the NaCl stress on alfalfa, and could increase plant height significantly (p<0.05), increase the chlorophyll content in plant and K+ content in root and leaf, decrease the content of Na+ and the ratio of Na+ / K + in leaf and root.Ameliorating effects of Ca2 + and SA treated separately and their combination on alfalfa seedlings were different, and combined treatment of Ca2+ and SA showed the best effect.Compared with control, the plant height of Medicago sativa L.cv.Gannong 3,Medicago sativa L.cv.Golden Empress and Medicago sativa L.cv.Xinjiang Daye increased by 46.1%,45.7% and 45.2%, the chlorophyll content increased by 3.71, 2.84 and 1.61 times respectively; the content of Na + in the root of Medicago sativa L.cv.Gannong 3, Medicago sativa L.cv.Golden Empress decreased by 94.9%, 89.4% respectively, and the content of Na+ in the leaf of Medicago sativa L.cv.Golden Empress decreased by 78.6%.With the weight ratio analysis of 3 treatments, the ameliorating effects of the combined treatment was more significant than Ca2+ or SA , and the ameliorating effects of SA was more than Ca2+.%通过盆栽试验,研究了NaCl胁迫下外源Ca2+与水杨酸(SA)对3种苜蓿(甘农3号、金皇后和新疆大叶)幼苗盐害的缓解效应.结果表明,外源Ca2+和SA对苜蓿幼苗的NaCl胁迫都有一定的缓解作用,能够显著(P<0.05)增加供试苜蓿植株的株高,提高植株叶绿素和根、叶K+含量,降低植株根、叶Na+含量和Na+/ K+.Ca2+和SA分别单独处理和二者复配处理对供试3个苜蓿品种的缓解效果不同,其中以Ca2+和SA复配组合处理效果最好.与对照相比,Ca2+

  11. Identification of genes induced during Medicago sativa nodule development by using the cDNA-AFLP technique

    Institute of Scientific and Technical Information of China (English)

    XIE Rong; HE Zhishui; LIU Fanghua; ZOU Huasong; ZHU Jiabi; YU Guanqiao

    2006-01-01

    A variety of genes involved in nodule development and function were induced during symbiotic root nodule development in alfalfa. We identified those genes by comparing the cDNA-amplified fragment length polymorphism (cDNA-AFLP) patterns of infected nodules and uninfected roots. Seventy-one transcript-derived fragments (TDFs) were isolated from about 3000 TDFs, which are enhanced or specifically expressed in nodule. The differential expression patterns of 61 genes were confirmed by reverse Northern hybridization or Northern hybridization analyses. Among these, 31 exhibited significant similarities to characterized database entries. These results suggest that the genes corresponding to the 31 TDFs may play important roles in signal transduction, gene expression and regulation, substance transportation or auto-regulation of nodulation during nodule development. The Northern hybridization analysis also indicates that the gene corresponding to TDF RX89 was not expressed in the nodule elicited by bacA mutant, presumably it is specially induced at the stage of nodule development when bacteroids begin to be differentiated.

  12. Transgenic expression of medicago truncatula PR10 and PR5 promoters in alfalfa shows pathogen-induced up-regulation of transgene expression

    Science.gov (United States)

    Genetic modification of alfalfa to introduce novel traits requires promoters for controlling gene expression. Promoters that are constitutively activated for expression of genes that enhance disease resistance pose a great energy load on the plant and exert a strong selective pressure on the pathoge...

  13. Contribution of exopeptidases to formation of nonprotein nitrogen during ensiling of alfalfa.

    Science.gov (United States)

    Tao, L; Zhou, H; Guo, X S; Long, R J; Zhu, Y; Cheng, W

    2011-08-01

    The experiment was conducted to investigate the exopeptidase classes in alfalfa (Medicago sativa L.) leaves, and to determine their contribution to the formation of nonprotein nitrogen (NPN) components during ensiling. Six classes of inhibitors that included bestatin (aminopeptidase inhibitor), potato carboxypeptidase inhibitor (PCI, carboxypeptidase inhibitor), 1,10-phenanthroline (dipeptidase inhibitor), diprotin A (dipeptidyl-peptidase inhibitor), butabindide (tripeptidyl-peptidase inhibitor), and dipeptide Phe-Arg (peptidyl-dipeptidase inhibitor) were used. To determine the contribution of each exopeptidase to the formation of NPN products, aqueous extracts of fresh alfalfa were fermented to imitate the proteolytic process of ensiled alfalfa and to ensure that each class of exopeptidase inhibitor would have immediate contact with the proteases in the alfalfa extract. Five classes of exopeptidases; namely, aminopeptidase, carboxypeptidase, dipeptidase, dipeptidyl-peptidase, and tripeptidyl-peptidase, were shown to be present in alfalfa leaves, each playing a different role in alfalfa protein degradation. Aminopeptidase, carboxypeptidase, and dipeptidase were the main exopeptidases contributing to the formation of NH(3)-N. Among the 5 exopeptidases, tripeptidyl-peptidase appeared to be the principal exopeptidase in hydrolyzing forage protein into peptides, whereas carboxypeptidase and dipeptidase appeared to be more important in contributing to the formation of amino acid-N. Dipeptidyl-peptidase and tripeptidyl-peptidase did not play a role in the formation of NH(3)-N or amino acid-N. Dipeptidase, carboxypeptidase, and tripeptidyl-peptidase were the principal exopeptidases for hydrolyzing forage protein into NPN during ensilage, and treatment with a mixture of the 5 inhibitors reduced the total NPN concentration in the fermented alfalfa extract to about 45% of that in the control after 21 d of fermentation.

  14. Producción de variedades de alfalfa y praderas polifitas de regadío en un suelo pardo calizo de la provincia de Granada

    OpenAIRE

    Ratera, C.; Muslera, E.; Ruiz Cornejo, J. A.

    2011-01-01

    Se presentan los resultados de unos ensayos realizados durante tres años en un suelo pardo calizo de la provincia de Granada, en la que se compararon 12 variedades de alfalfa (Medicago sativa L. cv Moapa, Galilea, Gilboa, Caliente, AS-13, AS-49, Peruana, Africana, Aragón, Albaida, Mireille y Alfa II) y las mezclas obtenidas de la combinación de cada una de las tres gramíneas, Lolium perenne L. Compás, Dactylis glomerata L. Bar aula, Festuca arundinacea Schreb. Manade, con cada una de las legu...

  15. Utilización de la tecnología NIRS con sonda de fibra óptica para el control de calidad de alfalfa

    OpenAIRE

    Hernández Hierro, José Miguel

    2008-01-01

    La alfalfa (Medicago Sativa L.) es uno de los principales forrajes producidos en el área mediterránea y de gran interés tanto desde el punto de vista agronómico como industrial. A su riqueza energética y proteica se unen los altos contenidos en ciertos minerales y vitaminas, entre ellas el alto contenido en vitamina E, lo que la convierte en una pieza importante dentro de la nutrición animal. La proteína bruta es un buen indicador de su valor energético, la posible adulteración por adición de...

  16. Alfalfa carbon and nitrogen sequestration patterns and effects of temperature and precipitation in three agro-pastoral ecotones of northern China.

    Directory of Open Access Journals (Sweden)

    Shujuan Chang

    Full Text Available Alfalfa (Medicago sativa L. is a primary and widely cultivated forage crop in China. As a perennial leguminous grass, continuous planted alfalfa may influence carbon and nitrogen sequestration in soils. We evaluated the effect of alfalfa, planted for different lengths of time, and temperature and precipitation on soil organic carbon (SOC and total nitrogen (TN contents, and estimated soil SOC and TN inventories from 0-60 cm in three agro-pastoral ecotones of northern China. Alfalfa SOC and TN storage patterns were significantly different with increasing soil depths between the three regions of northern China. Continuous alfalfa grassland planted had a positive effect on accumulation of both SOC and TN in the Northwest region, whereas SOC storage peaked 6-7 years after planting in the Northeast and North region. Moreover, relatively higher TN storage appeared 7 years after planting in the Northeast and North regions. This study controlled as many factors as possible, but we caution that such temporal inferences could be artifacts of site selection. The regression analysis indicated that SOC and TN accumulation was mainly dependent on temperature (≥10°C of effective total accumulated temperature in the North region. Precipitation in the growing season was the main limiting factor for SOC storage in the Northwest region and TN accumulation in the North regions. Therefore, the different climate factors affecting SOC and TN sequestration in alfalfa occurred at a regional scale.

  17. Using RNA-Seq for gene identification, polymorphism detection and transcript profiling in two alfalfa genotypes with divergent cell wall composition in stems

    Directory of Open Access Journals (Sweden)

    Lamb JoAnn FS

    2011-04-01

    Full Text Available Abstract Background Alfalfa, [Medicago sativa (L. sativa], a widely-grown perennial forage has potential for development as a cellulosic ethanol feedstock. However, the genomics of alfalfa, a non-model species, is still in its infancy. The recent advent of RNA-Seq, a massively parallel sequencing method for transcriptome analysis, provides an opportunity to expand the identification of alfalfa genes and polymorphisms, and conduct in-depth transcript profiling. Results Cell walls in stems of alfalfa genotype 708 have higher cellulose and lower lignin concentrations compared to cell walls in stems of genotype 773. Using the Illumina GA-II platform, a total of 198,861,304 expression sequence tags (ESTs, 76 bp in length were generated from cDNA libraries derived from elongating stem (ES and post-elongation stem (PES internodes of 708 and 773. In addition, 341,984 ESTs were generated from ES and PES internodes of genotype 773 using the GS FLX Titanium platform. The first alfalfa (Medicago sativa gene index (MSGI 1.0 was assembled using the Sanger ESTs available from GenBank, the GS FLX Titanium EST sequences, and the de novo assembled Illumina sequences. MSGI 1.0 contains 124,025 unique sequences including 22,729 tentative consensus sequences (TCs, 22,315 singletons and 78,981 pseudo-singletons. We identified a total of 1,294 simple sequence repeats (SSR among the sequences in MSGI 1.0. In addition, a total of 10,826 single nucleotide polymorphisms (SNPs were predicted between the two genotypes. Out of 55 SNPs randomly selected for experimental validation, 47 (85% were polymorphic between the two genotypes. We also identified numerous allelic variations within each genotype. Digital gene expression analysis identified numerous candidate genes that may play a role in stem development as well as candidate genes that may contribute to the differences in cell wall composition in stems of the two genotypes. Conclusions Our results demonstrate that RNA

  18. Effect of exchanging Onobrychis viciifolia and Lotus corniculatus for Medicago sativa on ruminal fermentation and nitrogen turnover in dairy cows.

    Science.gov (United States)

    Grosse Brinkhaus, A; Bee, G; Silacci, P; Kreuzer, M; Dohme-Meier, F

    2016-06-01

    The objective of the study was to determine the effect of feeding sainfoin (SF; Onobrychis viciifolia) and birdsfoot trefoil (BT; Lotus corniculatus), 2 temperate climate forage legumes that contain condensed tannins (CT), on ruminal fermentation and N turnover in dairy cows. Six ruminally cannulated multiparous dairy cows (milk yield=40kg/d; 36 d in milk) were used in a replicated 3×3 Latin square design. All animals were fed basal diets containing 20% pelleted SF (223g of CT/kg of dry matter), BT (30.3g of CT/kg of dry matter), or alfalfa (AL) and concentrate to meet their predicted nutrient requirements. Each experimental period consisted of a 21-d adaptation period in a tiestall, followed by a 7-d collection period in metabolic crates, where feces and urine were collected quantitatively. During the 7-d period, milk yield was recorded daily and milk samples were taken at each milking. Blood, ruminal fluid, and papillae were sampled on d 2 and 5. The relative abundance of selected bacterial strains in ruminal fluid and the gene expression of transporter genes in the papillae were determined with quantitative PCR. Total volatile fatty acids and the abundance of the cellulolytic bacteria Prevotella spp. and Ruminococcus flavefaciens decreased with SF compared with AL. The relative gene expression of the monocarboxylate transporter 1 was increased with BT compared with AL and SF. Total yields of milk, milk fat, and milk protein were similar among treatments. The proportion of 18:3n-3 in milk fat was greater and those of 22:5n-3 and 22:6n-3 were lower with SF than with BT. The contents of urea N in blood (2.71, 3.45, and 3.90mmol/L for SF, AL, and BT, respectively), milk (79.8, 100.1, and 110.9mg/kg for SF, AL, and BT, respectively), and urine were lower with SF than with AL and BT, and a trend toward a lower ruminal ammonia content occurred with SF compared with BT. Intake and excretion of N with milk were similar among treatments, but urine N was lower with SF

  19. System responses to long-term drought and re-watering of two contrasting alfalfa varieties.

    Science.gov (United States)

    Kang, Yun; Han, Yuanhong; Torres-Jerez, Ivone; Wang, Mingyi; Tang, Yuhong; Monteros, Maria; Udvardi, Michael

    2011-12-01

    Systems analysis of two alfalfa varieties, Wisfal (Medicago sativa ssp. falcata var. Wisfal) and Chilean (M. sativa ssp. sativa var. Chilean), with contrasting tolerance/sensitivity to drought revealed common and divergent responses to drought stress. At a qualitative level, molecular, biochemical, and physiological responses to drought stress were similar in the two varieties, indicating that they employ the same strategies to cope with drought. However, quantitative differences in responses at all levels were revealed that may contribute to greater drought tolerance in Wisfal. These included lower stomatal density and conductance in Wisfal; delayed leaf senescence compared with Chilean; greater root growth following a drought episode, and greater accumulation of osmolytes, including raffinose and galactinol, and flavonoid antioxidants in roots and/or shoots of Wisfal. Genes encoding transcription factors and other regulatory proteins, and genes involved in the biosynthesis of osmolytes and (iso)flavonoids were differentially regulated between the two varieties and represent potential targets for improving drought tolerance in alfalfa in the future.

  20. The effect of feeding sulla (Hedysarum coronarium) or lucerne (Medicago sativa) on lamb parasite burdens and development of immunity to gastrointestinal nematodes.

    Science.gov (United States)

    Niezen, J H; Charleston, W A G; Robertson, H A; Shelton, D; Waghorn, G C; Green, R

    2002-05-02

    Two experiments investigated the efficacy of the legume Hedysarum coronarium (sulla), which contains condensed tannins (CTs), for reducing gastrointestinal nematode infections relative to lucerne. Experiment 1 was aimed to show whether the lower faecal egg count (FEC) and larval establishment previously reported in lambs grazing sulla were due to direct effects of the forage on Ostertagia circumcincta and Trichostrongylus colubriformis or were mediated through an enhanced immune response. Experiment 2 evaluated the impact of feeding sulla relative to feeding lucerne (Medicago sativa), before, at, or after larval challenge on subsequent FECs and nematode burdens. In experiment 1, 64 Romney lambs were fed either freshly cut lucerne or sulla (32 lambs per herbage) for the duration of the trial. Within each herbage there were four treatment groups (n=8 per group). Initial levels of immunity were assessed in uninfected (UN) lambs which were maintained parasite-free until challenged with 15,000 O. circumcincta and 15,000 T. colubriformis larvae on day 63, and slaughtered on day 81. The other three treatment groups were trickle-infected with each of 5000 O. circumcincta and 5000 T. colubriformis larvae three times per week from day 1 to 35. Non-steroid infected (CONTROL) and steroid-treated (STER) groups were treated with anthelmintic on day 49 and challenged with 15,000 O. circumcincta and 15,000 T. colubriformis on day 63 and slaughtered on day 81. The STER lambs were given dexamethasone trimethylacetate from day 49 to 81 to determine effects of immunity on parasite infection. From day 35 an establishment group (EST) on each herbage was fed a common pelleted lucerne diet and slaughtered on day 56 to determine nematode establishment during trickle-infection. Diet did not affect FECs but feeding lucerne increased (Psulla. O. circumcincta numbers were lower (Psulla than lucerne. The sulla diet was associated with higher (Psulla diet but effects upon T. colubriformis

  1. Effect of Arbuscular Mycorrhizal Fungi Glomus spp. Inoculation on Alfalfa Growth in Soils with Copper Efecto de la Inoculación con Hongos Micorrízicos Arbusculares Glomus spp. sobre el Crecimiento de Alfalfa en Suelos con Cobre

    Directory of Open Access Journals (Sweden)

    Daniela Novoa M

    2010-06-01

    Full Text Available Soils near mining centers usually have high heavy metal (HM levels. It has been found that some plants associated with arbuscular mycorrhizal fungi (AMF improve growth and tolerance to HM in soils. This symbiosis is a biological resource for degraded soil recovery. The objective of this study was to determine the effect of inoculating AMF (Glomus spp. on alfalfa (Medicago sativa L. growth in agricultural soils with different copper (Cu levels for degraded soil recovery. To this effect, alfalfa seeds were grown in soils from the Catemu and Casablanca valleys and inoculated with AMF. Plant height, stem diameter, and number of leaves were measured weekly. Dry matter, mycorrhizal colonization, and Cu concentration in alfalfa plant tissues were measured after 81 days. Inoculation increased plant height by 24%, stem diameter by 11%, and number of leaves by 34%. Inoculation had a significant effect (p ≤ 0.05 on alfalfa plants that were grown in soil with the highest Cu concentration, but had no effect on Cu accumulation in alfalfa plant tissues. A direct relationship was observed between Cu accumulation in alfalfa and Cu concentration in soils. It was concluded that alfalfa inoculated with Glomus spp. is applicable to the soil recovery process whenever soil properties can ensure inoculum effectiveness on alfalfa growth, and avoid toxicity by excessive Cu in alfalfa plant tissues.Los suelos cercanos a centros de actividad minera suelen presentar altos niveles de metales pesados (HM. Se ha encontrado que algunas plantas asociadas a hongos micorrízicos arbusculares (AMF mejoran su crecimiento y tolerancia a los HM presentes en los suelos. Esta simbiosis constituye un recurso biológico para la recuperación de suelos degradados. El objetivo de este estudio fue determinar el efecto de la inoculación con AMF (Glomus spp. sobre el crecimiento de alfalfa (Medicago sativa L. en suelos agrícolas con distintos niveles de cobre (Cu para la recuperación de

  2. Efficacy of a BVDV subunit vaccine produced in alfalfa transgenic plants.

    Science.gov (United States)

    Peréz Aguirreburualde, María Sol; Gómez, María Cristina; Ostachuk, Agustín; Wolman, Federico; Albanesi, Guillermo; Pecora, Andrea; Odeon, Anselmo; Ardila, Fernando; Escribano, José M; Dus Santos, María José; Wigdorovitz, Andrés

    2013-02-15

    Bovine viral diarrhea virus (BVDV) is considered an important cause of economic loss within bovine herds worldwide. In Argentina, only the use of inactivated vaccines is allowed, however, the efficacy of inactivated BVDV vaccines is variable due to its low immunogenicity. The use of recombinant subunit vaccines has been proposed as an alternative to overcome this difficulty. Different studies on protection against BVDV infection have focused the E2 protein, supporting its putative use in subunit vaccines. Utilization of transgenic plants expressing recombinant antigens for the formulation of experimental vaccines represents an innovative and cost effective alternative to the classical fermentation systems. The aim of this work was to develop transgenic alfalfa plants (Medicago sativa, L.) expressing a truncated version of the structural protein E2 from BVDV fused to a molecule named APCH, that target to antigen presenting cells (APCH-tE2). The concentration of recombinant APCH-tE2 in alfalfa leaves was 1 μg/g at fresh weight and its expression remained stable after vegetative propagation. A methodology based an aqueous two phases system was standardized for concentration and partial purification of APCH-tE2 from alfalfa. Guinea pigs parentally immunized with leaf extracts developed high titers of neutralizing antibodies. In bovine, the APCH-tE2 subunit vaccine was able to induce BVDV-specific neutralizing antibodies. After challenge, bovines inoculated with 3 μg of APCH-tE2 produced in alfalfa transgenic plants showed complete virological protection.

  3. Soil factors exhibit greater influence than bacterial inoculation on alfalfa growth and nitrogen fixation.

    Science.gov (United States)

    Neumann, Ute; Kosier, Bob; Jahnke, Joachim; Priefer, Ursula B; Al-Halbouni, Djamila

    2011-09-01

    In order to study the effects of soil factors and bacterial inoculation on alfalfa (Medicago sativa), plants were inoculated with Ensifer meliloti L33 and Azospirillum brasilense Sp7 in pot experiments using two different soils separately as well as in a mixture. One soil was contaminated with chemical waste products; the other was an arable soil. Soil factors, including the availability of macro- and micronutrients as well as carbon and nitrogen contents, were found to exhibit a much greater influence on the growth of alfalfa than any of the inoculations. In contaminated soil, the shoot and root growth of alfalfa was decreased and nodules were diminished and ineffective. Bacterial inoculations did not significantly improve this hostile growth environment. However, in a mixture (44% arable, 22% contaminated soil, 34% vermiculite), growth conditions for alfalfa were improved so that shoot dry weight and nodule numbers increased up to 100- and 20-fold, respectively, compared with the contaminated soil. For the strain L33, its persistence in the rhizosphere was correlated to the presence of its host plant, but its dynamics were influenced by competition with indigenous rhizobia. The strain Sp7, once provided with a suitable soil, was not dependent on the plant's rhizosphere, but it enhanced the performance of L33 and native rhizobia.

  4. Overexpressing Arabidopsis ABF3 increases tolerance to multiple abiotic stresses and reduces leaf size in alfalfa.

    Science.gov (United States)

    Wang, Zhi; Su, Guoxia; Li, Min; Ke, Qingbo; Kim, Soo Young; Li, Hongbing; Huang, Jin; Xu, Bingcheng; Deng, Xi-Ping; Kwak, Sang-Soo

    2016-12-01

    Arabidopsis ABSCISIC ACID-RESPONSIVE ELEMENT-BINDING FACTOR 3 (ABF3), a bZIP transcription factor, plays an important role in regulating multiple stress responses in plants. Overexpressing AtABF3 increases tolerance to various stresses in several plant species. Alfalfa (Medicago sativa L.), one of the most important perennial forage crops worldwide, has high yields, high nutritional value, and good palatability and is widely distributed in irrigated and semi-arid regions throughout the world. However, drought and salt stress pose major constraints to alfalfa production. In this study, we developed transgenic alfalfa plants (cv. Xinjiang Daye) expressing AtABF3 under the control of the sweetpotato oxidative stress-inducible SWPA2 promoter (referred to as SAF plants) via Agrobacterium tumefaciens-mediated transformation. After drought stress treatment, we selected two transgenic lines with high expression of AtABF3, SAF5 and SAF6, for further characterization. Under normal conditions, SAF plants showed smaller leaf size compared to non-transgenic (NT) plants, while no other morphological changes were observed. Moreover, SAF plants exhibited enhanced drought stress tolerance and better growth under drought stress treatment, which was accompanied by a reduced transpiration rate and lower reactive oxygen species contents. In addition, SAF plants showed an increased tolerance to salt and oxidative stress. Therefore, these transgenic AtABF3 alfalfa plants might be useful for breeding forage crops with enhanced tolerance to environmental stress for use in sustainable agriculture on marginal lands.

  5. Karyotype and Cluster Analysis of 6 Alfalfa Materials%6个紫花苜蓿材料的核型及其亲缘关系分析

    Institute of Scientific and Technical Information of China (English)

    张雪婷; 杨文雄; 杨芳萍; 师尚礼; 尹国丽

    2011-01-01

    Karyotype analysis and cluster analysis was studied on 6 alfalfa materials by chromosome flaking and karyotype resemblance-near coefficient, The result showed that each material was tetraploid with 32chromosomes. The level of all materials on karyotype evolution was (Medicago sativa L. ,M. sativa,Xinjiangdaye) 2B> ( M, sativa , Regina 2000, M, sativa , Longdong, M. sativa , Pick 8925 ) 1B> ( M. sativa , Zhaodong) lA. However,Karyotype resemblance-near coefficient of each material was above 0.900 0. Furthermore,all materials were divided into 2 categories when the value of evolutionary distance was 0. 073 8,which M. sativa L. and M. sativa, Xinjiangdaye belonging to one category and the rest ones belonging to another category. All above showed the shape of chromosomes of M. sativa L. was more asymmetry. And the speed of its system evolution was faster than any other material in this experiment.%运用染色体压片法对陇东野生紫花苜蓿(Medicago sativa L.)等6个紫花苜蓿材料进行核型分析,并通过核型似近系数对供试材料进行聚类分析.结果显示:(1)全部供试材料皆为2n=32的四倍体,核型进化由高到低依次为:[陇东野生紫花苜蓿、新疆大叶紫花苜蓿(M.sativa,Xinjiangdaye)]2B>[皇后2000紫花苜蓿(M.sativa,Regina 2000)、陇东紫花苜蓿(M.sativa,Longdong)、Pick 8925紫花苜蓿(M.sativa,Pick 8925)]1B>[肇东紫花苜蓿(M.sativa,Zhaodong)]1A.(2)供试材料间的核型似近系数(λ)均在0.900 0以上,并在进化距离(De)0.073 8处分为两类,陇东野生紫花苜蓿和新疆大叶紫花苜蓿归为一类,其它供试材料归为另一类.研究表明,陇东野生紫花苜蓿的染色体较不对称,与其它供试材料相比,亲缘关系远,系统演化快.

  6. 紫花苜蓿对重金属污染河道底泥的修复能力研究%Research on Phytoremediation of Heavy Metal Pollution in River Sediment by Medicago sativa L.

    Institute of Scientific and Technical Information of China (English)

    吴卿; 高亚洁; 李东梅; 赵彩云

    2011-01-01

    [目的]研究紫花苜蓿(Medicago sativa L.)对河道底泥中重金属的修复作用,为利用植物修复技术解决受污染河道沉积物的重金属污染问题提供可靠依据。[方法]将过筛的底泥(以风干土计)混和均匀后装入长方形PVC箱(0.6m×0.5m×0.4m),底部设有渗流通气孔;将箱中底泥用去离子水调至30%~60%持水率(WHC)。2010年4月播入紫花苜蓿种子,生长7d后间苗,每隔30d采集植物根际土壤样品,监测底泥重金属含量、细菌及酶的活性。10月收获植物并测定植物根、茎、叶部分的重金属吸收情况。[结果]紫花苜蓿的同一部位对不同的重金属积累量不同,且同一重金属在植株的不同部位积累量也不同。紫花苜蓿对Zn的总积累量最大,且主要积累在根部;Ni、Cr、Cu和Pb也主要积累在根部;Mn在紫花苜蓿叶片中的积累最多,占植物中总积累量的42.47%;各种重金属在茎内的积累量均较低。紫花苜蓿对Ni、Cu、Pb和Cr的降解效果比较好,延长种植作物的种植时间或增加作物的播种次数有利于重金属的降解;紫花苜蓿对Mn的降解效果不明显。种植紫花苜蓿后,底泥中微生物数量显著增加,脱氢酶活性也有所提高。[结论]紫花苜蓿对Zn、Ni、Cr、Cu和Pb均有一定的修复作用,可以用于解决受污染河道底泥的重金属污染问题。%[Objective] The aim was to study the phytoremediation of heavy metal pollution in river sediment by Medicago sativa L.,so as to provide reliable references for the phytoremediation of heavy metal pollution in river sediment.[Method] The air-dried,screened and mixed sediment was put in rectangular PVC box(0.6 m×0.5 m×0.4 m) with seepage vent at the bottom,and the water holding capacity(WHC) of sediment was kept at 30%-60% by deionized water.The seeds of Medicago sativa L.were sown in April 2010,and seedlings were thinned after 7 d.Samples were collected from rhizosphere

  7. 紫花苜蓿MsZIP基因超表达载体的构建及转基因苜蓿检测%Construction and transformation of an over-expression plasmid of the MsZIP gene from Medicago sativa

    Institute of Scientific and Technical Information of China (English)

    李燕; 孙彦; 杨青川; 康俊梅; 张铁军; 房锋

    2012-01-01

    根据已经克隆得到的MsZIP基因(GenBank序列号:HQ911778),扩增编码区cDNA,构建植物超表达载体PBI-MsZIP.酶切鉴定表明,目的基因已经正确的插入到载体中,超表达载体构建成功.采用CaCl2冻融法将其转入农杆菌菌株中,然后采用农杆菌介导的方法,转化紫花苜蓿,共得到11株抗性苗,对其中的4株进行卡那霉素基因PCR检测,均得到了目的条带.同时对这4株抗性苗进行目的基因的RT-PCR检测,均得到了目的条带.说明MsZIP基因已经成功在苜蓿中超表达.为了进一步验证该基因的功能,分别用200 mmol/L NaCl和25μmol/LPEG-6000处理转基因苜蓿,3d后进行生理指标的测定.结果表明,MsZIP基因在苜蓿中超表达可以提高苜蓿的耐盐性和耐旱性.%Based on the MsZIP gene sequence (GenBank No. HQ911778), a cDNA fragment was cloned and connected to the PMD18-T vector to construct PMD-MsZJP. The target fragment and linear plasmid were obtained from the cloning vector PMD-MsZIP and from the plant expression vector PBI121 using dual digestion with Xbal and BatnYW. The plant over-expression vector PBI-MsZIP was built through directional connections using T4 DNA ligase. The plasmid was transferred to Agrobacterium LBA4404 by the CaCU freeze-thaw method and was then transferred into alfalfa by an Agrobacterium-mediated transformation system. Eleven kanamy-cin-resistant plants were obtained. Four of them were sampled to detect target fragments and PCR identification showed that the recombinant plasmid had been transferred into alfalfa. The MsZIP gene was successfully over-expressed in transgenic Medicago sativa CV. Zhongmu No. 1. To test the function of this gene, the trans-genic alfalfa was treated with 200 mmol/L NaCl and 25 jumol/L PEG-6000 for three days, and some physiological parameters were measured. The contents of soluble sugar, soluble protein and proline significantly increased , while the MDA content declined. Over-expressed MsZIP gene

  8. MtPAR MYB transcription factor acts as an on switch for proanthocyanidin biosynthesis in Medicago truncatula.

    Science.gov (United States)

    Verdier, Jerome; Zhao, Jian; Torres-Jerez, Ivone; Ge, Shujun; Liu, Chenggang; He, Xianzhi; Mysore, Kirankumar S; Dixon, Richard A; Udvardi, Michael K

    2012-01-31

    MtPAR (Medicago truncatula proanthocyanidin regulator) is an MYB family transcription factor that functions as a key regulator of proanthocyanidin (PA) biosynthesis in the model legume Medicago truncatula. MtPAR expression is confined to the seed coat, the site of PA accumulation. Loss-of-function par mutants contained substantially less PA in the seed coat than the wild type, whereas levels of anthocyanin and other specialized metabolites were normal in the mutants. In contrast, massive accumulation of PAs occurred when MtPAR was expressed ectopically in transformed hairy roots of Medicago. Transcriptome analysis of par mutants and MtPAR-expressing hairy roots, coupled with yeast one-hybrid analysis, revealed that MtPAR positively regulates genes encoding enzymes of the flavonoid-PA pathway via a probable activation of WD40-1. Expression of MtPAR in the forage legume alfalfa (Medicago sativa) resulted in detectable levels of PA in shoots, highlighting the potential of this gene for biotechnological strategies to increase PAs in forage legumes for reduction of pasture bloat in ruminant animals.

  9. 绿洲区苜蓿与鸭茅混播饲草的青贮发酵品质研究%Study on fermentation quality of mixed silage of Medicago sativa/Dactylis glomerata pasture in oasis area

    Institute of Scientific and Technical Information of China (English)

    张战胜; 于磊; 孙国君; 张前兵

    2015-01-01

    Forage from Medicago sativa/Dactylis glomerata pasture was used as raw material to make silage with 3 formulas(90% M.sativa + 10% D .glomerata ,70% + M.sativa + 30% D .glomerata and 50% M.sa-tiva + 50% D .glomerata)and the fermentation quality was tested.The results showed that the smell,texture, color and sensory of the mixed silage were excellent,and the pH value showed a decreasing trend.The quality was better than the single silage separately made with M.sativa and D .glomerata .The ammonia nitrogen con-tent of mixed silage reduced by 36.4% compared to single silage of M.sativa ,the acetic acid and propionic acid contents of D .glomerata silage obviously decreased.The mixed silage improved the lactic acid content and effec-tively inhibited the production of butyric acid.The butyric acid was not detected in treatments of M.sativa +D .glomerata(7∶3 and 5∶5 of mixing ratio).The crude protein content and detergent fiber of 3 mixed silage treatments were 31.9% higher and 12.6% lower than that of D .glomerata silage respectively.Therefore,the treatment of M.sativa + D .glomerata by 7∶3 ratio was the best.%以苜蓿(Medicago sativa )与鸭茅(Dactylis glomerata )混播草地牧草为材料,按照90%苜蓿+10%鸭茅、70%苜蓿+30%鸭茅、50%苜蓿+50%鸭茅的比例进行青贮,通过分析对比发酵品质、营养成分、感官青贮效果等,以期优化最佳混合青贮的豆∶禾比例。试验结果表明:苜蓿和鸭茅混合青贮后,气味、质地、色泽感官评定均为优良,且 pH 呈下降趋势,青贮效果优于苜蓿和鸭茅的单独青贮。混合青贮降低了苜蓿青贮中氨态氮含量的36.4%,鸭茅青贮中乙酸、丙酸的含量明显下降;提高了苜蓿青贮中乳酸的含量,有效抑制了丁酸的产生,苜蓿+鸭茅饲草混贮比例为7∶3和5∶5处理结果未检测出丁酸。3个混合青贮组合的粗蛋白含量高出鸭茅单贮31.9%,酸性洗涤纤维低于鸭茅青贮12.6%。在青

  10. 6种杂草对紫花苜蓿的化感作用%A Study of Allelopathy on Alfalfa with Six Variety of Weeds

    Institute of Scientific and Technical Information of China (English)

    王毅民

    2012-01-01

    This is a study of two alfalfa(Medicago sativa) seeds on seed germination and shoots growing by using water and ethanol extract from six kinds of weeds.The results show that Descuminia Sophia,Ex Prantl,Carduusnutans Linn,Chorispora tenella DC,Capsella bursa-pastoris,Trigonotis peduncularis,and Artemisia frigida Willd.Sp.Pl.all have different degrees of allelopathic effects on alfalfa.Water extracts from CarduusnutansLinn and Chorispora tenella(Pall.) DC,could significantly reduce stem lenghth,dry weight and seed germination rate of Longdong alfalfa and AErGangJin alfalfa.Allelopathy of weeds on AErGangJin alfalfa is greater than that on Longdong alfalfa.%以6种杂草水提液、醇提液对两种紫花苜蓿Medicago sativa品种种子萌发及幼苗生长的影响进行了研究.结果显示:播娘蒿Descuminia sophia(L.)webb.Ex Prantl、飞廉CarduusnutansLinn、离子草Chorisporatenella(Pall.)DC.、荠菜Capsella bursa-pastoris、附地菜Trigonotis peduncularis(Trev.)Benth.和冷蒿Artemis-ia frigida Willd.Sp.Pl.对紫花苜蓿均表现出不同程度的化感作用.飞廉和离子草的水提液显著降低了陇东苜蓿Longdong sativa和阿尔冈金Algonquin幼苗苗长、干质量以及种子的萌发率,播娘蒿的醇提液显著降低了阿尔冈金幼苗苗长、干物质以及种子的萌发率.阿尔冈金品种受杂草的化感作用的影响大于陇东苜蓿品种.

  11. Effect of PEG Stress on Key Enzymes Involved in Proline Metabolism of Medicago sativa cv.Pianguan%PEG胁迫对偏关苜蓿脯氨酸代谢途径关键酶的影响

    Institute of Scientific and Technical Information of China (English)

    朱慧森; 刘艳香; 董宽虎; 杨武德

    2011-01-01

    以山西地方品种偏关苜蓿(Medicago sativa cv.Pianguan)为试验材料,采用20%聚乙二醇(PEG-6000)分别处理不同时间(0,8,16,24,32,48和72 h),研究偏关苜蓿地上部及地下部的脯氨酸(proline,Pro)含量、鸟氨酸δ-氨基转移酶( ornithine-oxo-acidtransaminase,δ -OAT)、吡咯啉-5-羧酸合成酶(pyrroline- 5- carboxylate synthetase,P5CS)、脯氨酸脱氢酶(proline dehydragenase,ProDH)活性的动态变化.结果表明:PEG胁迫下,地上部Pro含量显著高于地下部,PEG处理40 h时,地上部Pro含量最高(3230.4 μg·g-1FW).地上部和地下部P5CS活性呈“升-降-升-降”的变化趋势.δ-OAT活性则在胁迫8h时升高,之后下降.ProDH活性受PEG胁迫显著降低,呈时间依赖性.PEG胁迫前期,偏关苜蓿的Pro积累以鸟氨酸-脯氨酸途径为主,随胁迫时间的延长,逐渐转为以谷氨酸-脯氨酸途径为主.%Medicago sativa cv. Pianguan is an important local variety in Pianguan of Shanxi province. This study focuses on the dynamic changes og proline (Pro) content and the activities of pyrroline-5-carboxylate synthetase (P5CS) , ornithine-oxo-acid transaminase (δ-OAT) and proline dehydragenase (ProDH) in both aboveground and underground parts of Medicago sativa cv. Pianguan under PEG-6000 stress for 0, 8, 16, 24, 32, 48 and 72 h, respectively. The proline content of aboveground parts was the highest (3230. 4 μg ? G-1 FW) when stressed for 40 h, which is significantly greater than that of underground parts. P5CS activity showed a tendency of rising- declining- rising- declining, while the δ-OAT activity was rising initially when stressed for 8 h, then declining. ProDH activity significantly declined for both aboveground and underground parts with increasing PEG-6000 stress time. In the earlier stage of PEG stress, the orni-thine-proline pathway is the main style for Medicago sativa cv. Pianguan responding to PEG stress, but the glutamate-proline pathway would gradually take over the

  12. EVALUATION OF THE FEED QUALITY OF FESTULOLIUM BRAUNII MIXTURES WITH MICROBIOLOGICALLY SUPPLIED RED CLOVER AND ALFALFA

    Directory of Open Access Journals (Sweden)

    Jacek Sosnowski

    2013-07-01

    Full Text Available The experience with cultivation of Festulolium braunii (Felopa variety in mixtures with red clover (Tenia variety, and alfalfa (Tula variety, was founded in April 2007 on an experimental object of Grassland Department and Green Areas Creation UP-H in Siedlce. The first experimental factor were 3-grass-legumes mixtures having the following composition: M1 – Festulolium braunii 50%, Trifolium pretense L. 50%, M2 – Festulolium braunii 50%, Medicago sativa ssp. media 50%, M3 – Festulolium braunii 50%, Trifolium pratense L. 25%, Medicago sativa ssp. media 25%. Combinations with soil’s medium amendment was marked as UG, and without soil’s medium amendment – BUG. In addition, nitrogen fertilization in the annual dose of 60 kg N∙ha-1, potassium 120 kg K2O∙ha-1 and phosphorus in the amount of 80 kg P2O5∙ha-1 were applied on all plots. Detailed study included the chemical composition of plant, which was determined at the Institute of Technology and Life Sciences in Falenty. The obtained results were used to calculate the following measures of the energy of and protein value feed: NEL – net energy of lactation, JPM∙kg-1D.M. – feed unit for milk production, JPŻ∙kg-1 D.M. – feed unit for livestock production, nBO – useful protein, BNŻ – rumen nitrogen balance. Furthermore, using the multivariate comparative of taxonomic analysis method the synthetic comparative measure of forage quality Q was evaluated. The use of soil’s medium amendment, regardless of the types of mixture, cuts and years of research, resulted in higher values of all measures. However, the analysis of synthetic measure of feed quality showed that in terms feed quality the best was the three component Festulolium braunii mixture with Trifolium pratense L. and Medicago sativa ssp. media.

  13. Growth Promotion and Disease Control Effect Determination of Endophytic Actinomycetes from Medicago sativa%首蓿内生拮抗放线菌的促生防病作用研究

    Institute of Scientific and Technical Information of China (English)

    王燕; 张绒仙

    2011-01-01

    [ Objective ] The research aimed to screen antagonistic endophytic actinomycetes from Medicago sativa. [ Method ] Growth promotion and disease control effect determination has been done by using Mx1, Mx3 and Mx5, which wcre isolated from the healthy Medicago sativa[ Result ] The result that the comparative control of Mx3 extracts could be 56.56%, 44.67% to Botrytis cinerea and Gaeumannomyces graminis var.tritici, respectively; the control effect of Mx3 extract was higher than it' s suspension. Mx3 extract had good effect on plant height and leaf quantity of tomato growing in the greenhouse; its growth-promoting abihty on wheat and cucumber was higher than water control. [ Conclusion ] Mx3 could promote growth of root, bud on both tomato and wheat, but it could restrain the growth of cucumber root.%[目的]从首蓿内生放线菌中筛选拮抗菌株.[方法]采用已从健康首蓿组织中分离得到的内生放线菌Mx1、Mx3、Mx5进行温室促生防病测定.[结果]菌株Mx3的发酵液对番茄灰霉病的防效可达56.56%,对小麦全蚀病的防效为44.67%;发酵液对2种病害的防效都明显高于菌悬液.对温室番茄株高、叶片数生长影响最明显;对小麦、黄瓜的促生均高于对照.[结论]菌株Mx3促生效果最好,其发酵液的防病效果明显优于菌悬液.

  14. NUTRITIONAL ENHANCEMENT OF ALFALFA THROUGH GENETIC ENGINEERING

    Directory of Open Access Journals (Sweden)

    J. Faragó

    2008-09-01

    Full Text Available Alfalfa (Medicago sativa L. is a pasture legume crop of primary importance to animal production throughout the world. The nutritional quality of alfalfa, as of other leguminous forage crops, is mainly determined by their content in selected essential amino acids (EAAs, such as methionine (Met and cysteine (Cys. In alfalfa, however, these S-containing amino acids constitute only about 1% or less of crude proteins (Frame et al., 1998. This is significantly less than the 3.5% Met+Cys content in the recommended FAO reference protein (FAO, 1973. Recent advances in genetic engineering allow to use the transgenic approach to increase the content of specific essential amino acids in target plant species. A number of different molecular approaches have been developed to address this issue, such as over-expression of a heterologous or homologous Met-rich protein, expression of a synthetic protein, modification of protein sequence, and metabolic engineering of the free amino acid pool and protein sink. To study the possibility of transgenic enhancement of nutritional quality of alfalfa, we used the approach of expression of a heterologous protein rich in Met+Cys in cells of alfalfa. The T-DNA introduced into the genome of alfalfa, using Agrobacterium tumefaciens-mediated genetic transformation, contained the selectable merker gene nptII for kanamycin (Kn resistance, and a cDNA of Ov gene from Japanese quail (Coturnix coturnix coding for a high Met+Cys containing ovalbumine (Mucha et al., 1991, both under constitutive promoters. After cocultivation of petiole segment- and leaf blade-explants of two highly embryogenic alfalfa genotypes Rg9/I-14-22 and Rg11/I-10-68 (Faragó et al., 1997 with cells of A. tumefaciens strain AGL1 carrying the nptII and Ov genes, and selection of transgenic cells on Kn containing selective media, more than one hundred putatively transgenic regenerants were obtained through somatic embryogenesis. Biological (Kn rooting assay

  15. Genome-Wide Investigation of MicroRNAs and Their Targets in Response to Freezing Stress in Medicago sativa L., Based on High-Throughput Sequencing.

    Science.gov (United States)

    Shu, Yongjun; Liu, Ying; Li, Wei; Song, Lili; Zhang, Jun; Guo, Changhong

    2016-01-22

    Winter damage, especially in northern climates, is a major limitation of the utilization of perennial forages such as alfalfa. Therefore, improving freezing tolerance is imperative in alfalfa genetic breeding. However, freezing tolerance is a complex trait that is determined by many genes. To understand the complex regulation mechanisms of freezing tolerance in alfalfa, we performed small RNA sequencing analysis under cold (4°) and freezing (-8°) stress. The sequencing results revealed that 173 known, and 24 novel miRNAs were expressed, and that the expression of 35 miRNAs was affected by cold and/or freezing stress. Meanwhile, 105 target genes cleaved by these miRNAs were characterized by degradome sequencing. These targets were associated with biological regulation, cellular processes, metabolic processes, and response to stress. Interestingly, most of them were characterized as transcription factors (TFs), including auxin response factors, SBP, NAC, AP2/ERF, and GRF, which play important roles in plant abiotic responses. In addition, important miRNAs and mRNAs involved in nodulation were also identified, for example, the relationship between miR169 and the TF CCAAT (also named as NF-YA/HAP2), which suggested that nodulation has an important function in freezing tolerance in alfalfa. Our results provide valuable information to help determine the molecular mechanisms of freezing tolerance in alfalfa, which will aid the application of these miRNAs and their targets in the improvement of freezing tolerance in alfalfa and related plants.

  16. Genome-Wide Investigation of MicroRNAs and Their Targets in Response to Freezing Stress in Medicago sativa L., Based on High-Throughput Sequencing

    Directory of Open Access Journals (Sweden)

    Yongjun Shu

    2016-03-01

    Full Text Available Winter damage, especially in northern climates, is a major limitation of the utilization of perennial forages such as alfalfa. Therefore, improving freezing tolerance is imperative in alfalfa genetic breeding. However, freezing tolerance is a complex trait that is determined by many genes. To understand the complex regulation mechanisms of freezing tolerance in alfalfa, we performed small RNA sequencing analysis under cold (4° and freezing (−8° stress. The sequencing results revealed that 173 known, and 24 novel miRNAs were expressed, and that the expression of 35 miRNAs was affected by cold and/or freezing stress. Meanwhile, 105 target genes cleaved by these miRNAs were characterized by degradome sequencing. These targets were associated with biological regulation, cellular processes, metabolic processes, and response to stress. Interestingly, most of them were characterized as transcription factors (TFs, including auxin response factors, SBP, NAC, AP2/ERF, and GRF, which play important roles in plant abiotic responses. In addition, important miRNAs and mRNAs involved in nodulation were also identified, for example, the relationship between miR169 and the TF CCAAT (also named as NF-YA/HAP2, which suggested that nodulation has an important function in freezing tolerance in alfalfa. Our results provide valuable information to help determine the molecular mechanisms of freezing tolerance in alfalfa, which will aid the application of these miRNAs and their targets in the improvement of freezing tolerance in alfalfa and related plants.

  17. Genome-Wide Investigation of MicroRNAs and Their Targets in Response to Freezing Stress in Medicago sativa L., Based on High-Throughput Sequencing

    Science.gov (United States)

    Shu, Yongjun; Liu, Ying; Li, Wei; Song, Lili; Zhang, Jun; Guo, Changhong

    2016-01-01

    Winter damage, especially in northern climates, is a major limitation of the utilization of perennial forages such as alfalfa. Therefore, improving freezing tolerance is imperative in alfalfa genetic breeding. However, freezing tolerance is a complex trait that is determined by many genes. To understand the complex regulation mechanisms of freezing tolerance in alfalfa, we performed small RNA sequencing analysis under cold (4°) and freezing (−8°) stress. The sequencing results revealed that 173 known, and 24 novel miRNAs were expressed, and that the expression of 35 miRNAs was affected by cold and/or freezing stress. Meanwhile, 105 target genes cleaved by these miRNAs were characterized by degradome sequencing. These targets were associated with biological regulation, cellular processes, metabolic processes, and response to stress. Interestingly, most of them were characterized as transcription factors (TFs), including auxin response factors, SBP, NAC, AP2/ERF, and GRF, which play important roles in plant abiotic responses. In addition, important miRNAs and mRNAs involved in nodulation were also identified, for example, the relationship between miR169 and the TF CCAAT (also named as NF-YA/HAP2), which suggested that nodulation has an important function in freezing tolerance in alfalfa. Our results provide valuable information to help determine the molecular mechanisms of freezing tolerance in alfalfa, which will aid the application of these miRNAs and their targets in the improvement of freezing tolerance in alfalfa and related plants. PMID:26801649

  18. Embryogenesis and plant regeneration of Medicago spp. in tissue culture.

    Science.gov (United States)

    Nagarajan, P; McKenzie, J S; Walton, P D

    1986-02-01

    Ten cultivars and breeding lines from two species of alfalfa (Medicago media and M. sativa) were screened for their ability to produce embryos and plantlets from the root and hypocotyl under three different tissue culture protocols. The three protocols differed in basal salt composition, vitamins, hormones and cytokinin additions. That protocol having a high 2-4,D low cytokinin induction step gave the highest percentage of embryogenic calli in some cultivars and lines. M. media cultivars and breeding lines had a high percentage of embryoid formation. M. sativa cultivars gave no embryoid formation. Two M. media breeding lines (Br1 and Le1), which were intermediate in the percentage of embryogenic calli formed from explants, had the highest number of regenerated plants established in soil. The creeping rooted M. media cultivar Heinrichs produced the highest percentage of embryogenic calli from explants but most of these embryoids were abnormal and failed to grow in soil or vermiculite. Accordingly, successful regeneration is directly related to the quality and quantity of the embryoids produced.

  19. Changes in the chemical properties and swelling coefficient of alfalfa root cell walls in the presence of toluene as a toxic agent.

    Science.gov (United States)

    Sharifi, M; Khoshgoftarmanesh, A H; Hadadzadeh, H

    2016-04-01

    The influence of toluene pollution on the chemical properties and swelling coefficient of root cell walls in alfalfa (Medicago sativa L.) was investigated. Two sets of alfalfa seedlings were selected and one set was treated with 450 mg L(-1) toluene in the nutrient solution under hydroponic culture. Thirty days after treatment with toluene, alfalfa plants were harvested and the root cell walls were isolated. Fourier-transform infrared (FTIR) spectroscopy was carried out for the characterization of the root cell walls composition. The cation exchange capacity (CEC) and the swelling coefficient of the root cell walls (Kcw) were estimated at various pH values. The toluene contamination significantly reduced the mass of the cell wall material in the alfalfa roots. According to the FTIR spectra, the toluene pollution can change the alfalfa root cell wall properties by reducing the cell wall functional groups. These functional groups are probably related to the proteins and polysaccharides in the cell wall. Also, toluene pollution strongly reduced CEC and Kcw of the root cell walls. The results show that the decrease in the active sites of adsorption on the root cell walls as a response to toluene pollution can affect the water flow rate and the mineral nutrients uptake by roots.

  20. Chemical composition of alfalfa silage with waste date and its feeding effect on ruminal fermentation characteristics and microbial protein synthesis in sheep.

    Science.gov (United States)

    Rajabi, R; Tahmasbi, R; Dayani, O; Khezri, A

    2016-09-07

    This study was conducted to evaluate the effect of feeding ensiled alfalfa with waste date on ruminal fermentation characteristics, microbial protein synthesis, protozoa population and blood parameters in sheep. Eight rams were used in a 2 × 2 change over design. Each experimental period consisted of 21 days including 16 days for adaptation and 5 days for sampling. For ensiling, fresh alfalfa (Medicago sativa L.) with different levels of waste date (Phoenix dactylifera L.) were mixed together and ensiled in 100-l containers for 45 days. Chemical composition of silages such as dry matter (DM), crude protein, NH3 -N, organic matter, NDF, ADF and pH were determined. Then, it was used as 30% (DM basis) in diets. The experimental diets were as follows: (i) control (diet containing alfalfa silage without waste date), (ii) diet containing alfalfa silage with 5 g waste date/95 g DM, (iii) diet containing alfalfa silage with 10 g waste date/90 g DM, and (iv) diet containing alfalfa silage with 15 g waste date/85 g DM. The results of this experiment showed that adding waste date to alfalfa during ensiling, improved silage quality, DM and energy level. Total protozoa population and all of holotrich, cellulolytic and entodinia in rumen fluid were increased linearly by increasing the level of waste date. Nitrogen (N) intake, urinary N excretion and nitrogen retention were affected by dietary treatments. Also, allantoin, uric acid, total purine derivatives, microbial protein synthesis, cholesterol level and blood urea nitrogen were significantly different. In conclusion, direct ensilage of alfalfa can be attained by mixing 15 g waste date/85 g DM and positive associative effects such as increased metabolizable energy (ME) and silage quality occurred.

  1. Effect of salinity on some growth indices and total protein content of alfalfa genotypes inoculated with Sinorhizobium meliloti strains under greenhouse conditions

    Directory of Open Access Journals (Sweden)

    A. Fazaeli

    2012-06-01

    Full Text Available This greenhouse experiment was carried out to evaluate the effects of salinity and bacterial inoculation on some growth indices and total protein content of alfalfa (Medicago sativa using a factorial completely randomized design with three replications. The effect of three salinity levels (0, 6 and 12 dS/m induced by a mixture of NaCl, CaCl2 and MgCl2 salts on growth indices and protein content of three alfalfa genotypes (Hamadani, Gharahyonjeh and Gharghalogh at three levels of inoculation with Sinorhizobium meliloti bacteria (no inoculation, inoculation with salinity-tolerant strain and inoculation with salinity-sensitive strain was investigated. After the isolation and purification of alfalfa-symbiotic-bacteria from alfalfa fields in Tehran province, two isolates of S. meliloti, one salinity-resistant and the other one salinity-sensitive, which are effective in symbiosis with alfalfa, were selected. Analysis of the results showed that by increasing the salinity level, the shoot and root dry weight, number of active nodules, and nitrogen (N concentration were decreased significantly (P<0.01. Inoculation with salinity-resistant strain of S. meliloti caused significant increase in shoot and root dry weight, number of active nodules, and N concentration of plants. Moreover, under saline conditions, the salinity-resistant S. meliloti strain increased significantly most alfalfa growth-indices and yield compared to control (without inoculation and inoculation with salinity-sensitive bacteria. There was no significant difference among alfalfa genotypes in yield and other growth indices under saline conditions. In general, the R59 isolate seems to be the best isolate of S. meliloti for greenhouse-grown alfalfa in saline conditions.

  2. 接种物添加量对紫花苜蓿常温厌氧发酵的影响%Influence of Inoculation Amount on Anaerobic Fermentation of Medicago sativa in Normal Temperature

    Institute of Scientific and Technical Information of China (English)

    张莉娟; 张无敌; 尹芳; 赵兴玲; 王昌梅; 柳静; 杨红; 刘士清

    2016-01-01

    以紫花苜蓿(Medicago sativa)为原料,分别加入30%、40%、50%的接种物,在常温下(20~22℃)、总固体(TS)含量为6%(以30%接种量计算)的条件下进行厌氧发酵,考察接种量对紫花苜蓿发酵的日产气量、pH、产气速率的影响.结果表明,接种量为40%时的产气效果良好,总产气量为3625 mL,比接种量为30%的试验组高8.05%,略低于接种量为50%的试验组.试验初期,pH出现一定下降,但很快又恢复至合适水平,整个阶段pH比较稳定.综合考虑,对于紫花苜蓿发酵,40%的接种量较优.%Using Medicago sativa as raw materials, the experiment was conducted to investigate the effect of different inocula-tion amount (30%, 40%, 50%) on gas production, gas production efficiency and pH value during the process of anaerobic fermentation, under the condition of 6% mass fraction of total solid (on the basis of inoculation amount 30%), normal tem-perature (20~22 ℃). The results showed that the total gas production was high and reached 3625 mL when inoculation amount was 40%, and it was 8.05% higher than the experimental group with inoculation amount 30%, slightly less than the experimental group with inoculation amount 50%. The pH value fluctuated in initial stage, but it returned to the appropri-ate levels soon, it was stable in the entire stage. Comprehensive consideration, inoculation amount 40% is much better for M. sativa.

  3. Supplementation of alfalfa (Medicago sativa) with condensed tannin-containing pellets of sericea lespedeza (Lespedeza cuneata): Effects on ruminant urinary urea excretion and digestibility

    Science.gov (United States)

    Some feedstuffs that contain condensed tannins can reduce urinary urea excretion without compromising nutrition for ruminant livestock. This results in reducing environmental impact, improving productivity and enhancing sustainability of ruminant farming operations. In some situations there are adva...

  4. Efecto de tres regímenes de cosecha en el comportamiento productivo de cinco variedades comerciales de alfalfa (Medicago sativa L.)

    OpenAIRE

    Marco Antonio Rivas-Jacobo; Cándido López-Castañeda; Alfonso Hernández-Garay; Jorge Pérez-Pérez

    2005-01-01

    La brucelosis es una enfermedad zoonótica que puede impactar fuerte en el ámbito económico, además de representar un delicado problema de salud pública. En México, el diagnóstico oficial se realiza por serología, mediante las pruebas de tarjeta, rivanol y fijación de complemento, considerándose el aislamiento y caracterización de Brucella spp como “la prueba de oro”. En este estudio se llevó a cabo la comparación de la técnica de reacción en cadena de la polimerasa (PCR por sus siglas en ingl...

  5. Application limestone forms and doses for alfalfa in no-tillage system

    Directory of Open Access Journals (Sweden)

    Letícia Cristina Bertusso Toffolli

    Full Text Available Alfalfa (Medicago sativa L. requires good soil fertility. Brazil is characterized by acidic soils which reduce the potential of the crop. Generally, liming is incorporated into the soil, but in tillage systems it is inadvisable. This study aimed to evaluate the effects of the lime application method and dose on pH, Al+3, V % and Ca+Mg in the soil and on dry matter yield of alfalfa cultivated under a consolidated no-tillage system. The experiment was conducted at the Experimental Station of Paraná Agronomic Institute, located in Pato Branco city, in Paraná state. The plots consisted of the types of lime application (plowing+harrowing, subsoil and surface, the sub-plots was the lime dose (0, 2, 4, 6 and 8 Mg ha-1 and the sub-sub-plots were the sampled soil depth (0-5; 5-10; 10-20 and 20-30 cm. The results show the application of lime, even superficially, caused increases in pH, concentration of Ca and Mg and base saturation of the soil, while also reducing the concentration of Al, especially in the surface layers of the soil. The practice of plowing and harrowing or of subsoiling, with the aim of lime incorporation in a consolidated no-tillage system is unnecessary. If it is required, the application of lime to the soil should be done superficially for alfalfa cultivated in this system.

  6. Biological activity of saponins from alfalfa tops and roots against Colorado potato beetle larvae

    Directory of Open Access Journals (Sweden)

    Maryla Szczepaniak

    2013-12-01

    Full Text Available The total saponins of alfalfa, Medicago sativa L., included in the diet of Colorado potato beetle larvae reduced their feeding, growth rate and survival. The biological activity of those compounds coming both from the roots and from the aerial parts is closely correlated with the dose. Larvae reared on leaves treated with a 0,5% dose virtually did not feed at all and died after 4-6 days. Lower saponin doses (0,01 and 0,001 % reduced the insects' feeding to a lesser degree. However, they inhibited their growth, caused an extension of the larval stage and mortality at a level of 76,7- 100%. No major differences have been found in saponin activity depending on its localization in the plant.

  7. Experimental Tests of the Light-Use Efficiency Model in Alfalfa

    Science.gov (United States)

    Castro, Saulo Manuel

    This study explored ways of integrating optical and flux measurements in the context of the Light Use Efficiency (LUE) model in an alfalfa ( Medicago sativa) field. Narrow-band spectrometers and low cost two-band radiometers provided alternate ways to measure NDVI and estimate the APAR term of the LUE model. The high temporal resolution of two-band sensors system accurately tracked seasonal carbon flux dynamics (R 2 = 0.96) demonstrating the value of automated, low cost approaches to monitoring NDVI and canopy light absorption, which was the dominant term in the LUE model for this agricultural field. At the seasonal scale PRI correlations with LUE varied with the LUE formulation, and suggested that seasonal PRI patterns were primarily driven by canopy structure changes. However, at the diurnal level, DeltaPRI correlated with changing efficiency. Combined optical and flux sampling can help partition flux data, gap-fill data, and add insights into the controls of carbon fluxes.

  8. Flue gas desulfurization products as sulfur sources for alfalfa and soybean

    Energy Technology Data Exchange (ETDEWEB)

    Chen, L.M.; Dick, W.A.; Nelson, S. [Ohio State University, Wooster, OH (US). School of Natural Resources

    2005-02-01

    Sulfur deficiencies in soil are expected to increase due to growth of high-yielding crop varieties, use of S-free fertilizers, and removal of S from industrial emissions. Flue gas desulfurization (FGD) products, created when coal is burned and SO{sub 2} is removed from the flue gases, may serve as efficient S sources. However, there are few reports on their use for the enhancement of crop growth. Agricultural gypsum and two types of FGD products, that contain either vermiculite or perlite, were applied at 0, 16, and 67 kg S ha{sup -1} to an agricultural soil (Wooster silt loam, Typic Fragiudalf). Dry weight of a new planting of alfalfa (Medicago sativa L.) was increased up to 40% by the treatments of FGD products or gypsum compared with the untreated control. Gypsum and FGD products were also applied at 0, 8,16, and 24 kg S ha{sup -1} to five established alfalfa stands in different Ohio regions. Mean alfalfa yield was significantly (P {le} 0.05) increased by approximately 5.0% in 2001 and 6.0% in 2002 with the S treatments of FGD products or gypsum compared with the untreated control. Alfalfa yields for FGD products and gypsum treatments were similar. A slight positive yield response was observed for soybean (Glycine max L.) when soils were treated with S-containing materials. Soil and plant analyses were made to assess potential adverse environmental impacts and none were observed. Thus, these FGD products can be safely applied to agricultural soils as S sources and can improve alfalfa yields in S-deficient soils.

  9. Digestibility and rate of passage by lambs of water-stressed alfalfa.

    Science.gov (United States)

    Undersander, D J; Cole, N A; Naylor, C H

    1987-06-01

    Two lamb digestion experiments were conducted to evaluate the effect of alfalfa [Medicago sativa (L.)] grown under varying levels of water deficiency (stress) on the rate of passage and digestibility of various fibrous components. Experiment 1 consisted of a randomized complete block design in which 12 Suffolk X Hampshire crossbred wethers averaging 40 kg were fed alfalfa hay grown at three (10, 15 or 20 cm water/ha) levels of water per harvest. Experiment 2 consisted of a switchback design in which four Hampshire wethers averaging 45 kg were fed alfalfa hay grown at two (5 or 20 cm/ha) levels of water per harvest. Forage yields ranged from 1,420 (10 cm/ha in Exp. 1) to 4,200 (20 cm/ha in Exp. 2) kg/ha. In both experiments, water stress reduced cell wall constituents (neutral detergent fiber), acid detergent fiber, lignin and cellulose content of the alfalfa hay. Organic matter digestibility was decreased when the percentage of leaves fell below 60% at the highest yield. Digestibility of N and the rate of NDF digestibility were not affected by water stress. The second experiment additionally included nutrient balance and rate of passage measurements. Greater (P less than .10) amounts of N and P were absorbed from water-stressed than nonstressed hay. Ruminal retention time of particulate markers tended (P less than .10) to increase with greater water stress. The results of this study are interpreted to indicate that while moderate water stress may have little effect on in vivo digestibility of alfalfa, severe stress may reduce digestibility of fibrous fractions and total organic matter.

  10. Increased photosynthetic acclimation in alfalfa associated with arbuscular mycorrhizal fungi (AMF) and cultivated in greenhouse under elevated CO2.

    Science.gov (United States)

    Goicoechea, Nieves; Baslam, Marouane; Erice, Gorka; Irigoyen, Juan José

    2014-11-15

    Medicago sativa L. (alfalfa) can exhibit photosynthetic down-regulation when grown in greenhouse conditions under elevated atmospheric CO2. This forage legume can establish a double symbiosis with nitrogen fixing bacteria and arbuscular mycorrhizal fungi (AMF), which may increase the carbon sink effect of roots. Our aim was to assess whether the association of alfalfa with AMF can avoid, diminish or delay the photosynthetic acclimation observed in previous studies performed with nodulated plants. The results, however, showed that mycorrhizal (M) alfalfa at the end of their vegetative period had lower carbon (C) discrimination than non-mycorrhizal (NM) controls, indicating photosynthetic acclimation under ECO2 in plants associated with AMF. Decreased C discrimination was due to the acclimation of conductance, since the amount of Rubisco and the expression of genes codifying both large and small subunits of Rubisco were similar or slightly higher in M than in NM plants. Moreover, M alfalfa accumulated a greater amount of soluble sugars in leaves than NM plants, thus favoring a down-regulation effect on photosynthetic rates. The enhanced contents of sugars in leaves coincided with a reduced percentage of arbuscules in roots, suggesting decreased sink of carbohydrates from shoots to roots in M plants. The shorter life cycle of alfalfa associated with AMF in comparison with the NM controls may also be related to the accelerated photosynthetic acclimation in M plants. Further research is needed to clarify to what extent this behavior could be extrapolated to alfalfa cultivated in the field and subjected to periodic cutting of shoots under climatic change scenarios.

  11. Effects of ozone and water stress on canopy temperature, water use, and water use efficiency of alfalfa

    Energy Technology Data Exchange (ETDEWEB)

    Temple, P.J. (Univ. of California, Riverside (USA)); Benoit, L.F. (Univ. of California, Davis (USA))

    Ozone (O{sub 3}) and soil water deficit are two environmental stresses that significantly affect the growth and yield of alfalfa (Medicago sativa L). However, little is known of the responses of field-grown alfalfa to O{sub 3}, and the effects of the interaction between O{sub 3} and water stress on canopy temperature and water relations of alfalfa have not been previously reported. The objective of this 2-yr study was to determine the interactive effects of O{sub 3} and soil water deficits on canopy temperatures, water use, and water use efficiency (WUE) of alfalfa. Alfalfa (cv. WL-514) was grown in 30-3- by 5.5-m plots on Wasco sandy loam (coarse-loamy, mixed, nonacid, thermic Typic Torriorthents) in Shafter, CA, and was exposed in open-top chambers to five levels of O{sub 3} for 12 h daily, from March to October of 1984 and 1985. Ozone treatments ranged from charcoal-filtered air (CF) to twice ambient O{sub 3} concentrations. Each plot received either normal amounts of irrigation (NI) or 30% less than normal (WS). Canopy temperature-air temperature differentials ({Tc}-T{sub a}) were significantly reduced by water stress an average of 27.9% in 1984 and 44.0% in 1985. Ozone also significantly reduced {Tc}-T{sub a} by 31% in NI and 37% in WS plots in 1984, but in 1985 O{sub 3} had no effect on {Tc}-T{sub a}. Water use, rate of soil water depletion, or depth of effective rooting zone were not affected by O{sub 3}, whereas water stress significantly reduced all three. Water use efficiency was significantly reduced by O{sub 3}, averaging 12% lower in nonfiltered compared with CF plots. The effects of O{sub 3} on WUE were attributed to premature senescence and abscission of older alfalfa leaves.

  12. Effects of AM Fungi on Growth and Physiological Characters of Medicago sativa L· under NaCl Stress%盐胁迫下AM真菌对紫花苜蓿生长及生理特征的影响

    Institute of Scientific and Technical Information of China (English)

    陆爽; 郭欢; 王绍明; 张霞

    2011-01-01

    The effects of AM fungi on the growth and physiological characters of Medicago sativa L. under NaCl stress were studied. Three NaC1 treatments levels of 0%, 0.5% and 1.0% were added to the soil for the potted plant. The results showed that application AMF influenced the growth of host plants (the height,P<0.05), the soluble sugar, soluble protein and proline content in roots were all increased along with the heighten of NaCl levels. The fresh-weight of the host plants roots was 1.27 times more heavier than non-inoculated under 1.0% NaCl; MDA content of each treatment in inoculated plant was lower than control;Pro content in leaves and roots of Medicago sativa L. were 0. 82, 1.41 times as the comparison under NaCl stress(1.0%). It could be concluded that AMF could not only accelerate the growth and accumulate the osmotic adjustment matter of host plant, but also keep a low level of MDA to reduce the salt-intimidate. Presuming that the different degree of depend on ABA in leaves and roots resulted in the difference of proline contain between.%利用盆栽试验研究了NaCl胁迫条件下AM真菌对紫花苜蓿(Medicago sativa L.)植株生长及生理特征的影响.结果显示:随土中加入NaCl浓度增高(0%,0.5%,1.0%),与未接菌紫花苜蓿相比,接种AM真菌显著(P<0.05)促进紫花苜蓿生长,并使其可溶性糖、可溶性蛋白及根系脯氨酸累积量增加.1.0%NaCl接种AM真菌处理下根系鲜重(28.1 mg)为0%NaCl未接种下的1.27倍;不同盐处理接种AM真菌植株丙二醛含量均低于对照株;1.0%NaCl浓度下接种AM菌植株叶片及根系脯氨酸含量分别为对照株的0.82,1.41倍.表明AM真菌在胁迫环境下不仅可促进植株生长发育及渗透调节物质的积累,还可维持植物体丙二醛含量较低水平,降低植株遭受盐胁迫,推测叶片与根系脯氨酸对ABA依赖程度不同而导致其脯氨酸含量不同.

  13. Isolation and Identification of Hydrogen-oxidizing Bacteria in Medicago sativa Rhizosphere%紫花苜蓿根际氢氧化细菌的分离与鉴定

    Institute of Scientific and Technical Information of China (English)

    付博; 王卫卫; 郝莹; 王莉娟; 唐明; 陈兴都

    2009-01-01

    利用气体循环培养体系从陕西乾县HUP-豆科植物紫花苜蓿(Medicago sativa)根际土壤中分离获得37株细菌.菌株氧化氢能力测定结果表明,8株菌氧化氢和自养生长能力较强,初步确定为氢氧化细菌类群;根据其形态特征、培养特征和生理生化特性,鉴定为7个不同属:假单胞菌属(Pseudomonas)、邻单胞菌属(Plesiomonas)、脂肪杆菌属(Pimelobacter)、黄色杆菌属(Xanthobacter)、勒米诺氏菌属(Leminorella)、地杆菌属(Terrabacter)和稀有杆菌属(Rarobacter);其中氧化氢能力最强的优势菌株WMQ-7 16S rDNA序列(GenBank登录号为EU807744)长度为1 451bp,GC含量为53.8%,其核苷酸序列与假单胞菌属同源性高于99%,在系统发育树上位于同一分支,将WMQ-7菌株鉴定为假单胞菌属(Pseudomonas).图2表5参16%Gas-cycle incubation system was used to enrich the Medicago sativa rhizosphere soil collected in Shaanxi Province, China and 37 strains of bacteria were isolated. Among them, 8 stains had stronger ability to oxidize hydrogen and could grow chemolithoautotrophically, so they were preliminarily identified as hydrogen-oxidizing bacteria. According to their cells, colony forms and biochemical characteristics, the 8 strains were identified as Pseudomonas, Plesiomonas, Pimelobacter, Xanthobacter, Leminorella, Terrabacter and Rarobacte. Strain WMQ-7 had the strongest ability to oxidize hydrogen, and its 16S rDNA sequence (GenBank accession number EU807744) was 1 451 bp and GC content was 53.8%. Strain WMQ-7 was clustered together with Pseuclomonas in phylogenic tree, with the sequence identity of 99%, Therefore, strain WMQ-7 was identified as Pseudomonas. Fig 2, Tab 5, Ref 16

  14. Effect of 60 Co-γradiation on some growth and nutrition indexes of Medicago sativa L.%60Co-γ辐射对紫花苜蓿部分生长及营养指标的影响

    Institute of Scientific and Technical Information of China (English)

    刘胜洪; 周玲艳; 杨妙贤; 刘文

    2015-01-01

    将紫花苜蓿( Medicago sativa L.)10个品种种子经2000 Gy剂量的60 Co-γ射线辐射处理,并就辐射处理对其部分生长和营养指标的影响进行了比较分析.结果显示,经60 Co-γ射线处理后,10种紫花苜蓿种子的萌发率、株高和营养指标等都发生了不同程度的变化.辐射处理对先行者、 WL525、 WL903和Adrenalian等紫花苜蓿品种种子萌发率的影响较小,而明显降低了其余大富豪、阿尔冈金、费纳尔、苜蓿王、标杆和WL2321等6个品种的种子萌发率;辐射处理对部分紫花苜蓿品种的生长速度有促进作用,而对部分品种的生长速度有抑制作用;辐射处理对大部分品种的粗蛋白、总糖、总氨基酸浓度有显著增高或降低作用,但对全部品种的干/鲜质量比无显著影响.%Ten Medicago sativa L.varieties were radiated by 2 000 Gy 60 Co-γray, and some growth and nutrition indexes were analyzed.The results showed that the germination rate, plant height and nutritional quality changed at different degrees after the radiation.The germination rates of six varieties, Million-aire, Algonguin, Fnal, Alfaking, Beraga and WL2321, were decreased by the radiation with no effect on those of four varieties, Xianxingzhe, WL525, WL903 and Adrenalian.Growth speed of partial varieties increased and that of partial varieties decreased after the radiation.Crude protein, total sugar and total a-mino acid contents of most varieties increased or decreased significantly but dry/fresh weight ratio of all changed with no significant difference after the radiation.

  15. 苜蓿混合凋萎青贮技术对青贮品质的影响%Effects of Mixed Wilting Silage Technology on Alfalfa Silage Quality

    Institute of Scientific and Technical Information of China (English)

    贾纳提; 刘梦; 李莉; 董志国; 麦丽亚·伊尔斯比克

    2012-01-01

    对苜蓿+无芒雀麦+披碱草和苜蓿+无芒雀麦+冰草的混播草地牧草采用凋萎青贮技术进行混合青贮,以单独凋萎青贮新疆大叶苜蓿设为对照,分析各处理青贮材料的pH值、CP、NDF、ADF、乙酸、乳酸、丙酸和氨态氮的变化,比较其混合青贮技术对青贮品质的影响。试验结果表明,苜蓿混合凋萎青贮无论从青贮感官指标,还是从青贮料的营养成分及有机酸含量,其表现比单独凋萎青贮效果好。在混合凋萎青贮处理的两个组合中,苜蓿+无芒雀麦+冰草混合青贮效果最理想。%The mixed wilting silage technology was used on Xinjiang big leaf alfalfa-Medicago sativa L. + Bromus inermis Leyss + Agropyron cristatum and Xinjiang big leaf alfalfa-Medicago sativa L. + Bromus inermis Leyss + Elymus dahuricus Turcz, and set single- wilting silage as control. PH value,CP, NDF, ADF, Butyric acid, Acetic acid, Propionic acid and NH3-N content in each treatment changes were analysed to compare the effects of mixed wilting silage technology on alfalfa silage quality .The results showed that alfalfa mixed wilting silage ,whether from the sensory index of silage, or from the nutrients and organic acid contents of silage to consider ,the effect was better than single-wilting silage. In the two combinations of mixed wilting silage treatment, the treatment Xinjiang big leaf alfalfa- Medicago sativa L. + Bromus inermis Leyss + Agropyron cristatum silage effect was better..

  16. Genome-Wide Association Study Identifies Loci for Salt Tolerance during Germination in Autotetraploid Alfalfa (Medicargo sativa L.) using Genotyping by Sequencing

    Science.gov (United States)

    : In this study, we used a diverse panel of alfalfa accessions to identify molecular markers associated with salt tolerance during germination by genome-wide association (GWA) mapping and genotyping-by-sequencing (GBS). Three levels of salt treatments were applied during seed germination. Phenotypic...

  17. 苜蓿核糖体基因物理定位及染色体荧光分带%Physical Localization of Ribosomal Genes and Chromosome DAPI Banding by in situ Hybridization in Medicago sativa L.

    Institute of Scientific and Technical Information of China (English)

    陈建民; 洪义欢; 王幼平; Steve Bowley; 万建民

    2006-01-01

    利用核糖体基因为探针对,二倍体和四倍体苜蓿(Medicago sativa)进行原位杂交,结果表明,45s在四倍体、二倍体种中总是以单位点位于核仁组织区,5s则有2~3个位点;以二倍体种的基因组DNA为探针的原位杂交表明,蓝花苜蓿(M.coerulea)和黄花苜蓿(M.falcata)均能与四倍体染色体进行杂交,仅杂交信号强弱的染色体数目有差别;荧光染料DAPI使苜蓿的染色体显示带纹,蓝花苜蓿的DAPI带与C-带基本一致.文章对四倍体苜蓿的可能来源进行了讨论.

  18. 紫花苜蓿和黄花苜蓿对黄瓜生长影响的研究%The effect of Medicago sativa and M. Hispida on growth of cucumber(cucumis sativus L.)

    Institute of Scientific and Technical Information of China (English)

    陈奇涵; 崔邑城; 杭悦宇; 周义锋

    2005-01-01

    以每株黄瓜(Cucumis sativus)施用100 g、200 g、400 g新鲜紫花苜蓿(Medicago sativa)及200 g干燥黄花苜蓿(M.hispida)施用剂量,研究了紫花苜蓿、黄花苜蓿对黄瓜生长的影响.结果表明,紫花苜蓿和黄花苜蓿对黄瓜的植株高度、座果数、成熟瓜数具有明显的促进作用,但都表现在果期早期或早中期;对黄瓜已座果的果实成熟、增重有促进作用.紫花苜蓿不同的施用剂量对黄瓜生长产生了不同程度的促进作用,其中400 g鲜(紫)/株组的各类指标优于其他2个组;干燥黄花苜蓿对黄瓜生长的各项指标也有较好的促进作用.

  19. Effect of Siloguard additives on the quality of Medicago sativa silages in silage silo%无机盐添加剂对窖贮紫花苜蓿品质的影响

    Institute of Scientific and Technical Information of China (English)

    刘振宇; 玉柱; 刘忠宽; 黄欣颖; 王宇通; 邵新庆

    2010-01-01

    以第2茬紫花首蓿(Medicago sativa)为原料,采用窖贮的方式,用青贮卫士(Siloguard)添加剂进行处理,设4个质量分数0、0.05%、0.1%和0.2%,探讨紫花苜蓿窖贮的可行性及添加剂的最佳质量分数,为大规模生产实践提供科学依据.试验结果表明:Siloguard添加剂对改善青贮料的感官、降低pH值、提高乳酸含童均有作用,但由于所加入添加剂的质量分数不同,窖贮后效果不一,以添加0.1% Siloguard效果最佳;加入添加剂后,青贮料的可溶性糖(WSC)含量显著提高,显著改善了紫花首蓿青贮料的品质.综合分析认为,青贮窖越深,青贮料发酵品质越好;窖贮添加Siloguard能改善青贮饲料的品质,推荐生产最佳添加质量分数为0.1%.

  20. Effect Of Priming Of Seeds Of Medicago Sativa ‘Bami’ With Gibberellic Acid On Germination, Seedlings Growth And Antioxidant Enzymes Activity Under Salinity Stress

    Directory of Open Access Journals (Sweden)

    Younesi Omid

    2014-12-01

    Full Text Available The experiment was conducted in order to study effects of seeds priming with gibberellic acid (GA3 at 0, 3, 5 and 8 mM on germination, growth and antioxidant enzymes activity in alfalfa seedlings under salinity stress (200 mM NaCl. All control seeds germinated. The rate of germinated seeds was reduced to 48% in the presence of NaCl, and increased to 76% after seeds priming with 5 mM GA3. Priming with 5 mM GA3 was also correlated with an increase of dry weight of seedlings derived from both stressed and non-stressed seeds as well as with the reduction of electrolyte leakage (EL and malondialdehyde (MDA level in salt stressed seedlings. The activity of superoxide dismutase, catalase, guaiacol peroxidase and ascorbate peroxidase in primed and non-primed seeds increased in the presence of NaCl and after priming of seeds with 5 mM GA3, whereas only small effect on glutathione reductase activity in both primed and non-primed seeds was observed. The total ascorbate level was higher in both stressed and non-stressed seedlings from primed seeds. These results suggest that GA3 priming might increase the salt tolerance of alfalfa seedlings through enhancing the activities of antioxidant enzymes and reducing the membrane damage as estimated using biomarkers, EL index and MDA content.

  1. Biochemical and Molecular Phylogenetic Study of Agriculturally Useful Association of a Nitrogen-Fixing Cyanobacterium and Nodule Sinorhizobium with Medicago sativa L.

    Directory of Open Access Journals (Sweden)

    E. V. Karaushu

    2015-01-01

    Full Text Available Seed inoculation with bacterial consortium was found to increase legume yield, providing a higher growth than the standard nitrogen treatment methods. Alfalfa plants were inoculated by mono- and binary compositions of nitrogen-fixing microorganisms. Their physiological and biochemical properties were estimated. Inoculation by microbial consortium of Sinorhizobium meliloti T17 together with a new cyanobacterial isolate Nostoc PTV was more efficient than the single-rhizobium strain inoculation. This treatment provides an intensification of the processes of biological nitrogen fixation by rhizobia bacteria in the root nodules and an intensification of plant photosynthesis. Inoculation by bacterial consortium stimulates growth of plant mass and rhizogenesis and leads to increased productivity of alfalfa and to improving the amino acid composition of plant leaves. The full nucleotide sequence of the rRNA gene cluster and partial sequence of the dinitrogenase reductase (nifH gene of Nostoc PTV were deposited to GenBank (JQ259185.1, JQ259186.1. Comparison of these gene sequences of Nostoc PTV with all sequences present at the GenBank shows that this cyanobacterial strain does not have 100% identity with any organisms investigated previously. Phylogenetic analysis showed that this cyanobacterium clustered with high credibility values with Nostoc muscorum.

  2. Biochemical and Molecular Phylogenetic Study of Agriculturally Useful Association of a Nitrogen-Fixing Cyanobacterium and Nodule Sinorhizobium with Medicago sativa L.

    Science.gov (United States)

    Karaushu, E V; Lazebnaya, I V; Kravzova, T R; Vorobey, N A; Lazebny, O E; Kiriziy, D A; Olkhovich, O P; Taran, N Yu; Kots, S Ya; Popova, A A; Omarova, E; Koksharova, O A

    2015-01-01

    Seed inoculation with bacterial consortium was found to increase legume yield, providing a higher growth than the standard nitrogen treatment methods. Alfalfa plants were inoculated by mono- and binary compositions of nitrogen-fixing microorganisms. Their physiological and biochemical properties were estimated. Inoculation by microbial consortium of Sinorhizobium meliloti T17 together with a new cyanobacterial isolate Nostoc PTV was more efficient than the single-rhizobium strain inoculation. This treatment provides an intensification of the processes of biological nitrogen fixation by rhizobia bacteria in the root nodules and an intensification of plant photosynthesis. Inoculation by bacterial consortium stimulates growth of plant mass and rhizogenesis and leads to increased productivity of alfalfa and to improving the amino acid composition of plant leaves. The full nucleotide sequence of the rRNA gene cluster and partial sequence of the dinitrogenase reductase (nifH) gene of Nostoc PTV were deposited to GenBank (JQ259185.1, JQ259186.1). Comparison of these gene sequences of Nostoc PTV with all sequences present at the GenBank shows that this cyanobacterial strain does not have 100% identity with any organisms investigated previously. Phylogenetic analysis showed that this cyanobacterium clustered with high credibility values with Nostoc muscorum.

  3. Cadmium-induced hydrogen sulfide synthesis is involved in cadmium tolerance in Medicago sativa by reestablishment of reduced (homo)glutathione and reactive oxygen species homeostases.

    Science.gov (United States)

    Cui, Weiti; Chen, Huiping; Zhu, Kaikai; Jin, Qijiang; Xie, Yanjie; Cui, Jin; Xia, Yan; Zhang, Jing; Shen, Wenbiao

    2014-01-01

    Until now, physiological mechanisms and downstream targets responsible for the cadmium (Cd) tolerance mediated by endogenous hydrogen sulfide (H2S) have been elusive. To address this gap, a combination of pharmacological, histochemical, biochemical and molecular approaches was applied. The perturbation of reduced (homo)glutathione homeostasis and increased H2S production as well as the activation of two H2S-synthetic enzymes activities, including L-cysteine desulfhydrase (LCD) and D-cysteine desulfhydrase (DCD), in alfalfa seedling roots were early responses to the exposure of Cd. The application of H2S donor sodium hydrosulfide (NaHS), not only mimicked intracellular H2S production triggered by Cd, but also alleviated Cd toxicity in a H2S-dependent fashion. By contrast, the inhibition of H2S production caused by the application of its synthetic inhibitor blocked NaHS-induced Cd tolerance, and destroyed reduced (homo)glutathione and reactive oxygen species (ROS) homeostases. Above mentioned inhibitory responses were further rescued by exogenously applied glutathione (GSH). Meanwhile, NaHS responses were sensitive to a (homo)glutathione synthetic inhibitor, but reversed by the cotreatment with GSH. The possible involvement of cyclic AMP (cAMP) signaling in NaHS responses was also suggested. In summary, LCD/DCD-mediated H2S might be an important signaling molecule in the enhancement of Cd toxicity in alfalfa seedlings mainly by governing reduced (homo)glutathione and ROS homeostases.

  4. Endogenous hydrogen sulfide enhances salt tolerance by coupling the reestablishment of redox homeostasis and preventing salt-induced K⁺ loss in seedlings of Medicago sativa.

    Science.gov (United States)

    Lai, Diwen; Mao, Yu; Zhou, Heng; Li, Feng; Wu, Mingzhu; Zhang, Jing; He, Ziyi; Cui, Weiti; Xie, Yanjie

    2014-08-01

    Despite the external application of hydrogen sulfide (H2S) conferring plant tolerance against various environmental cues, the physiological significance of l-cysteine desulfhydrase (L-DES)-associated endogenous H2S production involved in salt-stress signaling was poorly understood. To address this gap, the participation of in planta changes of H2S homeostasis involved in alfalfa salt tolerance was investigated. The increasing concentration of NaCl (from 50 to 300 mM) progressively caused the induction of total l-DES activity and the increase of endogenous H2S production. NaCl-triggered toxicity symptoms (175 mM), including seedling growth inhibition and lipid peroxidation, were alleviated by sodium hydrosulfide (NaHS; 100 μM), a H2S donor, whereas aggravated by an inhibitor of l-DES or a H2S scavenger. A weaker or negative response was observed in lower or higher dose of NaHS. Further results showed that endogenous l-DES-related H2S modulated several genes/activities of antioxidant defence enzymes, and also regulated the contents of antioxidant compounds, thus counterbalancing the NaCl-induced lipid peroxidation. Moreover, H2S maintained K(+)/Na(+) homeostasis by preventing the NaCl-triggered K(+) efflux, which might be result form the impairment of SKOR expression. Together, our findings indicated that endogenous H2S homeostasis enhance salt tolerance by coupling the reestablishment of redox balance and restraining K(+) efflux in alfalfa seedlings.

  5. Cadmium-induced hydrogen sulfide synthesis is involved in cadmium tolerance in Medicago sativa by reestablishment of reduced (homoglutathione and reactive oxygen species homeostases.

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    Weiti Cui

    Full Text Available Until now, physiological mechanisms and downstream targets responsible for the cadmium (Cd tolerance mediated by endogenous hydrogen sulfide (H2S have been elusive. To address this gap, a combination of pharmacological, histochemical, biochemical and molecular approaches was applied. The perturbation of reduced (homoglutathione homeostasis and increased H2S production as well as the activation of two H2S-synthetic enzymes activities, including L-cysteine desulfhydrase (LCD and D-cysteine desulfhydrase (DCD, in alfalfa seedling roots were early responses to the exposure of Cd. The application of H2S donor sodium hydrosulfide (NaHS, not only mimicked intracellular H2S production triggered by Cd, but also alleviated Cd toxicity in a H2S-dependent fashion. By contrast, the inhibition of H2S production caused by the application of its synthetic inhibitor blocked NaHS-induced Cd tolerance, and destroyed reduced (homoglutathione and reactive oxygen species (ROS homeostases. Above mentioned inhibitory responses were further rescued by exogenously applied glutathione (GSH. Meanwhile, NaHS responses were sensitive to a (homoglutathione synthetic inhibitor, but reversed by the cotreatment with GSH. The possible involvement of cyclic AMP (cAMP signaling in NaHS responses was also suggested. In summary, LCD/DCD-mediated H2S might be an important signaling molecule in the enhancement of Cd toxicity in alfalfa seedlings mainly by governing reduced (homoglutathione and ROS homeostases.