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Sample records for perennial ryegrass lolium

  1. Effects of mesotrione on perennial ryegrass (Lolium perenne L.) carotenoid concentrations under varying environmental conditions.

    PubMed

    McCurdy, James D; McElroy, J Scott; Kopsell, Dean A; Sams, Carl E; Sorochan, John C

    2008-10-01

    Mesotrione is a carotenoid biosynthesis inhibiting herbicide, which is being evaluated for use in turfgrass. Carotenoids are important light harvesting and photoprotecting pigments that dissipate and quench excess light energy. The effects of mesotrione on carotenoid concentrations in turf and weed species, such as perennial ryegrass (Lolium perenne L.), are poorly understood. Mesotrione injury to perennial ryegrass has been reported, and symptomology may differ due to postapplication environmental factors such as irradiance and temperature. Research was conducted to investigate the effects of mesotrione on perennial ryegrass under varying irradiance (600, 1100, or 1600 micromol/m (2)/s) at three different temperatures (18, 26, and 34 degrees C). Postapplication irradiance and temperature levels did not affect visual injury symptoms in perennial ryegrass. Bleaching of treated plants was highest 7 days after treatment (DAT; 8%) and recovered to nontreated levels by 21 DAT. Mesotrione applications did not decrease perennial ryegrass foliar biomass accumulations. Carotenoid concentrations of nontreated plants were similar to those reported in creeping bentgrass and many green leafy vegetable crops. However, chlorophyll a and b, beta-carotene, lutein, and violaxanthin concentrations decreased due to mesotrione applications, while phytoene and zeaxanthin, a photoprotecting carotenoid, increased. The photochemical efficiency (F v/ F m) of treated plants was lower than nontreated plants at 3 and 7 DAT; however, treated plants recovered to nontreated levels 21 DAT. Results indicate that postapplication irradiance and temperature levels may not affect mesotrione efficacy in perennial ryegrass. Preferential accumulation of zeaxanthin following mesotrione applications may be a stress-related response, which may reduce light harvesting complex size and directly quench excess light energy. PMID:18788815

  2. Gene expression analysis of perennial ryegrass (Lolium perenne) using cDNA microarrays

    NASA Astrophysics Data System (ADS)

    Ong, Eng-Kok; Sawbridge, Tim; Webster, Tracie; Emmerling, Michael; Nguyen, Nga; Nunan, Katrina; O'Neill, Matthew; O'Toole, Fiona; Rhodes, Carolyn; Simmonds, Jason; Tian, Pei; Wearne, Katherine; Winkworth, Amanda; Spangenberg, German

    2003-07-01

    Perennial ryegrass (Lolium perenne) is a major forage grass of temperate pastures. A genomics program has been undertaken generating over 52,000 expressed sequence tags (ESTs). Cluster analysis of the ESTs identified approximately 14,600 ryegrass unigenes. In this report, we described the application of ryegrass unigene cDNAs to produce ryegrass 15K microarray. Fifteen microarray hybridisations were performed with labeled total RNA isolated from a variety of plant organs and developmental stages. In a proof of concept, gene expression profiling of ryegrass ESTs using the 15K unigene microarrays has been established using several known genes and two cluster analysis approaches (parallel coordinate planes plot and hierarchical clustering). The expression profile of the known genes (e.g. rubisco and invertase) corresponds well with published data. The microarray expression profile of a ryegrass putative root specific kinase gene was also verified with Northern blotting. This combination of DNA microarray hybridisations and cluster analysis can be applied as a tool for the identification of novel sequences of unknown function.

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

    PubMed Central

    2014-01-01

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

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

    PubMed

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

    2014-01-01

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

  5. Complete Chloroplast Genome Sequence of a Major Allogamous Forage Species, Perennial Ryegrass (Lolium perenne L.)

    PubMed Central

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

    2009-01-01

    Lolium perenne L. (perennial ryegrass) is globally one of the most important forage and grassland crops. We sequenced the chloroplast (cp) genome of Lolium perenne cultivar Cashel. The L. perenne cp genome is 135 282 bp with a typical quadripartite structure. It contains genes for 76 unique proteins, 30 tRNAs and four rRNAs. As in other grasses, the genes accD, ycf1 and ycf2 are absent. The genome is of average size within its subfamily Pooideae and of medium size within the Poaceae. Genome size differences are mainly due to length variations in non-coding regions. However, considerable length differences of 1–27 codons in comparison of L. perenne to other Poaceae and 1–68 codons among all Poaceae were also detected. Within the cp genome of this outcrossing cultivar, 10 insertion/deletion polymorphisms and 40 single nucleotide polymorphisms were detected. Two of the polymorphisms involve tiny inversions within hairpin structures. By comparing the genome sequence with RT–PCR products of transcripts for 33 genes, 31 mRNA editing sites were identified, five of them unique to Lolium. The cp genome sequence of L. perenne is available under Accession number AM777385 at the European Molecular Biology Laboratory, National Center for Biotechnology Information and DNA DataBank of Japan. PMID:19414502

  6. Ecological assessment of soil using a soil elutriate and the perennial ryegrass, Lolium perenne

    SciTech Connect

    Lawrence, C.; Meyers-Shone, L.; Duh, D.

    1995-12-31

    A 28-day plant bioassay using the perennial ryegrass, Lolium perenne, was utilized for an ecological assessment of soil from a hazardous waste site. An elutriate of the test soil was prepared and nutrients added, so that the seedlings would have direct exposure via uptake and to control for poor plant growth due to a lack of nutrients or proper soil profile characteristics. Use of an elutriate as the exposure medium assumes that those contaminants that can become waterborne for uptake by plants in the site conditions is the same as those which can be separated from adsorption to soil particulates during elutriate preparation. The ryegrass seeds were planted in a hydroponic system consisting of an upper chamber with an inert soil for a growth matrix and a lower reservoir with the nutrient and soil elutriate. Polyester cords were used to continuously wick the solution up to the inert soil and the chambers were drenched twice daily with the solution in the reservoir. At the conclusion of the study the plants` shoot length and dry weight (biomass) were measured to assess phytotoxicity of constituents in soil. The results of the test plants parameters were statistically compared to control plants to determine if test soil elutriates caused a measurable effect on ryegrass, The results of this plant bioassay provided additional and useful information for assessment of test soil.

  7. Dissecting the regulation of fructan metabolism in perennial ryegrass (Lolium perenne) with quantitative trait locus mapping.

    PubMed

    Turner, L B; Cairns, A J; Armstead, I P; Ashton, J; Skøt, K; Whittaker, D; Humphreys, M O

    2006-01-01

    Quantitative trait locus (QTL) mapping, which can be a useful tool for dissecting complex traits, has been used here to study the regulation of fructan metabolism in temperate forage grasses. An F2 mapping family, derived from a high water-soluble carbohydrate (WSC) x low WSC cross, was used to map fructans and the other components of WSC (sucrose, glucose and fructose) in leaves and tiller bases of perennial ryegrass (Lolium perenne) in spring and autumn. To characterize regions of the genome that control basic carbohydrate metabolism, a strategy to minimize the impact of genotype (G) x environment (E), and E-effects on the characterization of G-effects, was adopted. Most traits were highly variable within the family. There was also considerable year-to-year environmental variation. However, significant genetic effects were detected, and several traits had high broad-sense heritability. QTL were identified on chromosomes 1, 2, 5 and 6. Leaf and tiller base QTL did not coincide. Individual QTL explained between 8 and 59% of the total phenotypic variation in the traits. Fructan turnover, metabolism and their genetic control, and the effect of environment, are discussed in the context of the results. PMID:16390418

  8. Molecular characterisation and genetic mapping of candidate genes for qualitative disease resistance in perennial ryegrass (Lolium perenne L.)

    PubMed Central

    Dracatos, Peter M; Cogan, Noel OI; Sawbridge, Timothy I; Gendall, Anthony R; Smith, Kevin F; Spangenberg, German C; Forster, John W

    2009-01-01

    Background Qualitative pathogen resistance in both dicotyledenous and monocotyledonous plants has been attributed to the action of resistance (R) genes, including those encoding nucleotide binding site – leucine rich repeat (NBS-LRR) proteins and receptor-like kinase enzymes. This study describes the large-scale isolation and characterisation of candidate R genes from perennial ryegrass. The analysis was based on the availability of an expressed sequence tag (EST) resource and a functionally-integrated bioinformatics database. Results Amplification of R gene sequences was performed using template EST data and information from orthologous candidate using a degenerate consensus PCR approach. A total of 102 unique partial R genes were cloned, sequenced and functionally annotated. Analysis of motif structure and R gene phylogeny demonstrated that Lolium R genes cluster with putative ortholoci, and evolved from common ancestral origins. Single nucleotide polymorphisms (SNPs) predicted through resequencing of amplicons from the parental genotypes of a genetic mapping family were validated, and 26 distinct R gene loci were assigned to multiple genetic maps. Clusters of largely non-related NBS-LRR genes were located at multiple distinct genomic locations and were commonly found in close proximity to previously mapped defence response (DR) genes. A comparative genomics analysis revealed the co-location of several candidate R genes with disease resistance quantitative trait loci (QTLs). Conclusion This study is the most comprehensive analysis to date of qualitative disease resistance candidate genes in perennial ryegrass. SNPs identified within candidate genes provide a valuable resource for mapping in various ryegrass pair cross-derived populations and further germplasm analysis using association genetics. In parallel with the use of specific pathogen virulence races, such resources provide the means to identify gene-for-gene mechanisms for multiple host pathogen

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

    PubMed

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

    2010-11-01

    Water-soluble carbohydrates (WSC) are an important factor determining the nutritional value of grass forage and development of genetic markers for selection of WSC traits in perennial ryegrass would benefit future breeding programmes. Quantitative trait loci (QTLs) for WSC have been published for an F(2) ryegrass mapping family. Markers showing significant associations with these QTLs were used to design narrow-based populations with homozygosity for target QTLs. Founders were selected from within the mapping family. The divergent populations produced were analysed for WSC content in the glasshouse and the field. There was evidence of complex interactions between WSC content and other factors and traits, including the scale of assessment, time/degree of sward establishment and other forage quality parameters. Differences between the divergent pairs of the various populations were small. However, differences observed between the founder selection groups were maintained and the roles of the QTL regions in regulating forage WSC content were confirmed. In general, the individual divergent populations exploited only a limited extent of the large phenotypic variation available within the mapping family. However, this study sets the scene for exploring the opportunities for marker-assisted breeding strategies for complex traits in obligate out-breeding species, and the challenges of doing this are discussed. PMID:20617301

  10. Identification of QTLs for morphological traits influencing waterlogging tolerance in perennial ryegrass (Lolium perenne L.).

    PubMed

    Pearson, Allison; Cogan, Noel O I; Baillie, Rebecca C; Hand, Melanie L; Bandaranayake, Champa K; Erb, Stacey; Wang, Junping; Kearney, Gavin A; Gendall, Anthony R; Smith, Kevin F; Forster, John W

    2011-02-01

    Perennial ryegrass is a globally cultivated obligate outbreeding diploid species (2n = 2x = 14) which is subjected to periods of waterlogging stress due to flood irrigation during winter and the lead-up to summer. Reduction of oxygen supply to root systems due to waterlogging produces consequent deleterious effects on plant performance. Framework genetic maps for a large-scale genetic mapping family [F₁(NA(x) × AU₆)] were constructed containing 91 simple sequence repeat and 24 single nucleotide polymorphism genetic markers. Genetic trait dissection using both control and waterlogging treatments was performed in the glasshouse, a total of 143 maximally recombinant genotypes being selected from the overall sib-ship and replicated threefold in the trial. Analysis was performed for nine quantitative morphological traits measured 8 weeks after stress treatments were applied. A total of 37 quantitative trait loci (QTLs) were identified; 19 on the NA(x) parental genetic map, and 18 on the AU₆ parental genetic map. Regions of particular interest were identified on linkage groups (LGs) 4 and 3 of the respective maps, which have been targeted for further analysis by selection of critical recombinants. This first study of genetic control of waterlogging tolerance in ryegrasses has important implications for breeding improvement of abiotic stress adaptation. PMID:20981402

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

    NASA Astrophysics Data System (ADS)

    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.

  12. Development of a Genomic Microsatellite Library in Perennial Ryegrass (Lolium perenne) and its Use in Trait Mapping

    PubMed Central

    King, J.; Thorogood, D.; Edwards, K. J.; Armstead, I. P.; Roberts, L.; Skøt, K.; Hanley, Z.; King, I. P.

    2008-01-01

    Background and Aims Perennial ryegrass (Lolium perenne) is one of the key forage and amenity grasses throughout the world. In the UK it accounts for 70 % of all agricultural land use with an estimated farm gate value of £6 billion per annum. However, in terms of the genetic resources available, L. perenne has lagged behind other major crops in Poaceae. The aim of this project was therefore the construction of a microsatellite-enriched genomic library for L. perenne to increase the number of genetic markers available for both marker-assisted selection in breeding programmes and gene isolation. Methods Primers for 229 non-redundant microsatellite markers were designed and used to screen two L. perenne genotypes, one amenity and one forage. Of the 229 microsatellites, 95 were found to show polymorphism between amenity and forage genotypes. A selection of microsatellite primers was selected from these 95 and used to screen two mapping populations derived from intercrossing and backcrossing the two forage and amenity grass genotypes. Key Results and Conclusions The utility of the resulting genetic maps for analysis of the genetic control of target traits was demonstrated by the mapping of genes associated with heading date to linkage groups 4 and 7. PMID:18281692

  13. Heavy-metal absorption by perennial ryegrass and Swiss chard grown in potted soils amended with ashes from 18 municipal refuse incinerators. [Lolium perenne; Beta vulgaris L

    SciTech Connect

    Bache, C.A.; Lisk, D.J. )

    1990-01-01

    Perennial ryegrass (Lolium perenne) and swiss chard (Beta vulgaris L.) were grown in pots of mardin silt loam soil amended with 5 or 10% by weight of fly ash, bottom ash, or mixtures of both from 18 municipal refuse incinerators representing about one-fourth of all those operating in the US. The ash and plant material were analyzed for total cadmium, lead, and zinc. The correlation coefficients (r) for the concentration of cadmium, lead, and zinc in the ashes and that in the following crops were, respectively, as follows: ryegrass (first cutting), 0.9964, 0.7600, 0.9699; ryegrass (second cutting), 0.9946, 0.6895, 0.9474; swiss chard, 0.9153, 0.7609., 0.9580. Poor plant growth occurred in a few of the treatments containing ash notably higher in dissolved solids, cadmium, and zinc. The origin and association of heavy metals in refuse ash and their reactions in soils are reviewed.

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

    PubMed

    Gasperl, Anna; Morvan-Bertrand, Annette; Prud'homme, Marie-Pascale; van der Graaff, Eric; Roitsch, Thomas

    2015-01-01

    Fructans are polymers of fructose and one of the main constituents of water-soluble carbohydrates in forage grasses and cereal crops of temperate climates. Fructans are involved in cold and drought resistance, regrowth following defoliation and early spring growth, seed filling, have beneficial effects on human health and are used for industrial processes. Perennial ryegrass (Lolium perenne L.) serves as model species to study fructan metabolism. Fructan metabolism is under the control of both synthesis by fructosyltransferases (FTs) and breakdown through fructan exohydrolases (FEHs). The accumulation of fructans can be triggered by high sucrose levels and abiotic stress conditions such as drought and cold stress. However, detailed studies on the mechanisms involved in the regulation of fructan metabolism are scarce. Since different phytohormones, especially abscisic acid (ABA), are known to play an important role in abiotic stress responses, the possible short term regulation of the enzymes involved in fructan metabolism by the five classical phytohormones was investigated. Therefore, the activities of enzymes involved in fructan synthesis and breakdown, the expression levels for the corresponding genes and levels for water-soluble carbohydrates were determined following pulse treatments with ABA, auxin (AUX), ethylene (ET), gibberellic acid (GA), or kinetin (KIN). The most pronounced fast effects were a transient increase of FT activities by AUX, KIN, ABA, and ET, while minor effects were evident for 1-FEH activity with an increased activity in response to KIN and a decrease by GA. Fructan and sucrose levels were not affected. This observed discrepancy demonstrates the importance of determining enzyme activities to obtain insight into the physiological traits and ultimately the plant phenotype. The comparative analyses of activities for seven key enzymes of primary carbohydrate metabolism revealed no co-regulation between enzymes of the fructan and sucrose pool

  15. Plant vigour at establishment and following defoliation are both associated with responses to drought in perennial ryegrass (Lolium perenne L.)

    PubMed Central

    Hatier, Jean-Hugues B.; Faville, Marty J.; Hickey, Michael J.; Koolaard, John P.; Schmidt, Jana; Carey, Brandi-Lee; Jones, Chris S.

    2014-01-01

    Periodic drought events present a significant and, with climate change, increasing constraint on temperate forage plants’ production. Consequently, improving plants’ adaptive response to abiotic stress is a key goal to ensure agricultural productivity in these regions. In this study we developed a new methodology, using both area-based comparison and soil water content measurements of individual non-irrigated and irrigated clones, to assess performance of perennial ryegrass (Lolium perenne L.) genotypes subjected to moisture stress in a simulated competitive environment. We applied this method to the evaluation of a full-sibling population from a pair cross between genotypes from a New Zealand cultivar and a Moroccan ecotype. Our hypothesis was that: (i) both leaf lamina regrowth after defoliation (LR) and plant vigour affect plant performance during drought and rehydration; and (ii) quantitative trait loci (QTLs) associated with plant performance under moisture stress could be identified. Differences amongst genotypes in dry matter (DM) production, early vigour at establishment, leaf elongation rate and LR were measured. LR explained most of the variation in DM production during exposure to moisture deficit and rehydration followed by plant vigour, indicated by initial DM production in both treatments and subsequent measures of DM production of irrigated clones. We identified two main QTL regions associated with DM production and LR, both during drought exposure and rehydration. Further research focused on these regions should improve our understanding of the genetic control of drought response in this forage crop and potentially other grass species with significant synteny, and support improvement in performance through molecular breeding approaches. PMID:25104762

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

    PubMed Central

    Gasperl, Anna; Morvan-Bertrand, Annette; Prud'homme, Marie-Pascale; van der Graaff, Eric; Roitsch, Thomas

    2016-01-01

    Fructans are polymers of fructose and one of the main constituents of water-soluble carbohydrates in forage grasses and cereal crops of temperate climates. Fructans are involved in cold and drought resistance, regrowth following defoliation and early spring growth, seed filling, have beneficial effects on human health and are used for industrial processes. Perennial ryegrass (Lolium perenne L.) serves as model species to study fructan metabolism. Fructan metabolism is under the control of both synthesis by fructosyltransferases (FTs) and breakdown through fructan exohydrolases (FEHs). The accumulation of fructans can be triggered by high sucrose levels and abiotic stress conditions such as drought and cold stress. However, detailed studies on the mechanisms involved in the regulation of fructan metabolism are scarce. Since different phytohormones, especially abscisic acid (ABA), are known to play an important role in abiotic stress responses, the possible short term regulation of the enzymes involved in fructan metabolism by the five classical phytohormones was investigated. Therefore, the activities of enzymes involved in fructan synthesis and breakdown, the expression levels for the corresponding genes and levels for water-soluble carbohydrates were determined following pulse treatments with ABA, auxin (AUX), ethylene (ET), gibberellic acid (GA), or kinetin (KIN). The most pronounced fast effects were a transient increase of FT activities by AUX, KIN, ABA, and ET, while minor effects were evident for 1-FEH activity with an increased activity in response to KIN and a decrease by GA. Fructan and sucrose levels were not affected. This observed discrepancy demonstrates the importance of determining enzyme activities to obtain insight into the physiological traits and ultimately the plant phenotype. The comparative analyses of activities for seven key enzymes of primary carbohydrate metabolism revealed no co-regulation between enzymes of the fructan and sucrose pool

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

    PubMed Central

    2012-01-01

    Background In crop species, QTL analysis is commonly used for identification of factors contributing to variation of agronomically important traits. As an important pasture species, a large number of QTLs have been reported for perennial ryegrass based on analysis of biparental mapping populations. Further characterisation of those QTLs is, however, essential for utilisation in varietal improvement programs. Results A bibliographic survey of perennial ryegrass trait-dissection studies identified a total of 560 QTLs from previously published papers, of which 189, 270 and 101 were classified as morphology-, physiology- and resistance/tolerance-related loci, respectively. The collected dataset permitted a subsequent meta-QTL study and implementation of a cross-species candidate gene identification approach. A meta-QTL analysis based on use of the BioMercator software was performed to identify two consensus regions for pathogen resistance traits. Genes that are candidates for causal polymorphism underpinning perennial ryegrass QTLs were identified through in silico comparative mapping using rice databases, and 7 genes were assigned to the p150/112 reference map. Markers linked to the LpDGL1, LpPh1 and LpPIPK1 genes were located close to plant size, leaf extension time and heading date-related QTLs, respectively, suggesting that these genes may be functionally associated with important agronomic traits in perennial ryegrass. Conclusions Functional markers are valuable for QTL meta-analysis and comparative genomics. Enrichment of such genetic markers may permit further detailed characterisation of QTLs. The outcomes of QTL meta-analysis and comparative genomics studies may be useful for accelerated development of novel perennial ryegrass cultivars with desirable traits. PMID:23137269

  18. Characterization of Proanthocyanidins from Seeds of Perennial Ryegrass (Lolium perenne L.) and Tall Fescue (Festuca arundinacea) by Liquid Chromatography-Mass Spectrometry.

    PubMed

    Fraser, Karl; Collette, Vern; Hancock, Kerry R

    2016-09-01

    Perennial ryegrass (Lolium perenne) and tall fescue (Festuca arundinacea) are forage species of the grass family (Poaceae) that are key components of temperate pasture-based agricultural systems. Proanthocyanidins (PAs) are oligomeric flavonoids that, when provided as part of a farm animal's diet, have been reported to improve animal production and health. Up to now, forage grasses have been deemed not to produce PAs. This paper reports for the first time the detection of polymerized PAs in aqueous methanolic extracts of seed tissue of both perennial ryegrass and tall fescue, using LC-MS/MS. We have determined the structure of the PAs to be trans-flavan-3-ol-based, consisting predominately of afzelechin and catechin and linked primarily by B-type bonds. Investigations into the leaf tissue of both species failed to detect any PAs. This discovery opens the possibility of using genetic engineering tools to achieve tannin accumulation in leaf tissue of perennial ryegrass and tall fescue. PMID:27532250

  19. Nitrous oxide emission factors for urine and dung from sheep fed either fresh forage rape (Brassica napus L.) or fresh perennial ryegrass (Lolium perenne L.).

    PubMed

    Luo, J; Sun, X Z; Pacheco, D; Ledgard, S F; Lindsey, S B; Hoogendoorn, C J; Wise, B; Watkins, N L

    2015-03-01

    In New Zealand, agriculture is predominantly based on pastoral grazing systems and animal excreta deposited on soil during grazing have been identified as a major source of nitrous oxide (N2O) emissions. Forage brassicas (Brassica spp.) have been increasingly used to improve lamb performance. Compared with conventional forage perennial ryegrass (Lolium perenne L.), a common forage in New Zealand, forage brassicas have faster growth rates, higher dry matter production and higher nutritive value. The aim of this study was to determine the partitioning of dietary nitrogen (N) between urine and dung in the excreta from sheep fed forage brassica rape (B. napus subsp. oleifera L.) or ryegrass, and then to measure N2O emissions when the excreta from the two different feed sources were applied to a pasture soil. A sheep metabolism study was conducted to determine urine and dung-N outputs from sheep fed forage rape or ryegrass, and N partitioning between urine and dung. Urine and dung were collected and then used in a field plot experiment for measuring N2O emissions. The experimental site contained a perennial ryegrass/white clover pasture on a poorly drained silt-loam soil. The treatments included urine from sheep fed forage rape or ryegrass, dung from sheep fed forage rape or ryegrass, and a control without dung or urine applied. N2O emission measurements were carried out using a static chamber technique. For each excreta type, the total N2O emissions and emission factor (EF3; N2O-N emitted during the 3- or 8-month measurement period as a per cent of animal urine or dung-N applied, respectively) were calculated. Our results indicate that, in terms of per unit of N intake, a similar amount of N was excreted in urine from sheep fed either forage rape or ryegrass, but less dung N was excreted from sheep fed forage rape than ryegrass. The EF3 for urine from sheep fed forage rape was lower compared with urine from sheep fed ryegrass. This may have been because of plant

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

    PubMed Central

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

    2015-01-01

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

  1. Lambs fed fresh winter forage rape (Brassica napus L.) emit less methane than those fed perennial ryegrass (Lolium perenne L.), and possible mechanisms behind the difference.

    PubMed

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

    2015-01-01

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

  2. Stress memory induced transcriptional and metabolic changes of perennial ryegrass (Lolium perenne) in response to salt stress.

    PubMed

    Hu, Tao; Jin, Yupei; Li, Huiying; Amombo, Erick; Fu, Jinmin

    2016-01-01

    Preexposure to a stress could induce stable signals and reactions on plant physiology and gene expression during future encounters as a 'stress memory'. In this study, we found that two trainable genes, BPSP encoding putative brown plant hopper susceptibility protein and sucs encoding sucrose synthase displayed transcriptional memory for their considerably higher transcript levels during two or more subsequent stresses (S3, S4) relative to the initial stress (S0), and their expression returning to basal transcript levels (non-stressed) during the recovery states (R1, R2 and R3). Removing the repetitive stress/recovery exercise, activated transcriptional memory from two trainable genes persisted for at least 4 days in perennial ryegrass. The pretrainable genes with stress memory effort had higher response to the subsequent elevated NaCl concentration treatment than the non-trainable plants, which was confirmed by lower electrolyte leakage and minimum H2 O2 and O2 (-) accumulation. Salt stress elevated the content of 41 metabolites in perennial ryegrass leaves, and sugars and sugar alcohol accounted for more than 74.1% of the total metabolite content. The salt stress memory was associated with higher contents of 11 sugars and 1 sugar alcohol in the pretrainable grass leaves. Similarly, six sugars showed greater content in the pretrainable grass roots. These novel phenomena associated with transcriptional memory and metabolite profiles could lead to new insights into improving plant salinity acclimation process. PMID:25913889

  3. QTL ANALYSIS OF FIBER COMPONENTS AND CRUDE PROTEIN IN AN ANNUAL X PERENNIAL RYEGRASS POPULATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Annual (Lolium multiflorum Lam.) and perennial (Lolium perenne L.) ryegrass are two common forage species in temperate regions. Improving the digestibility of forage by decreasing fiber content is a major goal in forage crop breeding programs. An annual X perennial ryegrass population was used to ma...

  4. Feeding strategies for small-scale dairy systems based on perennial (Lolium perenne) or annual (Lolium multiflorum) ryegrass in the central highlands of Mexico.

    PubMed

    Heredia-Nava, D; Espinoza-Ortega, A; González-Esquivel, C E; Arriaga-Jordán, C M

    2007-04-01

    Small-scale dairying is an option for campesinos in Mexico. The costs of feeding are high and strategies based on quality forages are a priority. The performance, agronomic variables and feeding costs were evaluated for dairy cows continuously grazing perennial ryegrass-white clover for 9 h/day (PRG) or fed cut herbage from annual ryegrass for 8 weeks followed by 9 h/day for 6 weeks on a tethered rotational grazing pattern (ARG). All cows received 3 kg/day of an 18% crude protein (CP) concentrate. A 14-week split-plot on-farm experiment was designed with 10 cows from two participating farmers, and 1.5 ha per strategy. Milk yield was recorded weekly and milk composition, live weight and body condition score were recorded every 14 days. Net herbage accumulation was greater for ARG (8222 kg organic matter (OM)/ha) than for PRG (5915 kg OM/ha) (p<0.05), with higher CP in PRG (p<0.05). Milk yield was 19 kg/cow per day for PRG and 15.9 kg/ cow per day for ARG (p>0.05). Over 14 weeks, PRG produced 1422 kg more milk. There were no differences for live weight or condition score (p>0.05), but linear regression shows a live weight gain of 0.200 kg/cow per day for PRG. Protein and fat content showed no differences (p>0.05), but milk fat content in PRG was below standard. ARG had 60% higher costs, and margins were 38% higher in PRG. ARG has a place in rain-fed fields. The results provide viable options for improving these systems that may be suitable in their socio-economic context and their social and personal objectives. PMID:17691542

  5. Identification of genes associated with cold acclimation in perennial ryegrass.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sensitivity to cold temperatures restricts the cultivation of perennial ryegrass (Lolium perenne L.) in some temperate areas. Understanding cold-acclimation mechanisms is important for plant cultivation and breeding for cold tolerance. Our objective was to profile the transcriptome in perennial ry...

  6. Predation of italian ryegrass (Lolium multiflorum) seed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Italian ryegrass (Lolium multiflorum Lam.) can be a productive and high-quality cool-season forage, but is considered a weed in some pastures. Italian ryegrass does not form a persistent seed bank and needs to produce sufficient seed annually for effective re-establishment. Before the re-seeding ...

  7. Adhesion of Bacteroides succinogenes in pure culture and in the presence of Ruminococcus flavefaciens to cell walls in leaves of perennial ryegrass (Lolium perenne).

    PubMed Central

    Latham, M J; Brooker, B E; Pettipher, G L; Harris, P J

    1978-01-01

    Bacteroides succinogenes and Ruminococcus flavefaciens are two of the most important cellulolytic bacteria in the rumen. Adhesion of B. succinogenes in pure culture, and in mixed culture with R. flavefaciens, to the various types of cell walls in sections of perennial ryegrass (Lolium perenne L. cultivar S24) leaves was examined by transmission and scanning electron microscopy. B. succinogenes adhered to the cut edges of most plant cell walls except those of the meta- and protoxylem. It also adhered, though in much smaller numbers, to the uncut surfaces of mesophyll, epidermal, and phloem cell walls. In mixed culture, both species adhered in significant numbers to the cut edges of most types of plant cell wall, but R. flavefaciens predominated on the epidermis, phloem, and sclerenchyma cell walls. B. succinogenes predominated on the cut edges and on the uncut surfaces of the mesophyll cell walls, and its ability to adhere to uncut surfaces of other cell walls was not affected by the presence of the ruminococcus. Both organisms rapidly digested the epidermal, mesophyll, and phloem cell walls. Zones of digestion were observed around bacteria of both species when attached to the lignified cell walls of the sclerenchyma, but not when attached to the lignified xylem vessels. Images PMID:567035

  8. Haemodynamics of lambs grazing perennial ryegrass (Lolium perenne L.) either infected with AR6 novel wild-type endophyte or not infected

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Coopworth ewe lambs were randomly assigned to 3, 0.10-ha pastures of ‘Extreme’ perennial ryegrass that were infected with the AR6 novel endophyte (AR6; n=5), infected with the wild-type endophyte (WT; n=6), or was endophyte-free (Nil; n=5). Lambs were conditioned to the pastures from 25 Feb. to 16 ...

  9. Freeze tolerance of perennial ryegrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Perennial ryegrass is the most widely grown cool season grass in the world. Seed producers are developing more productive and more persistent varieties for North America. Different varieties exhibit a wide range of characteristics such as maturity, winter-hardiness, disease resistance, digestibility...

  10. Production of phenolics and the emission of volatile organic compounds by perennial ryegrass (Lolium perenne L.)/Neotyphodium lolii association as a response to infection by Fusarium poae.

    PubMed

    Pańka, Dariusz; Piesik, Dariusz; Jeske, Małgorzata; Baturo-Cieśniewska, Anna

    2013-07-15

    Grasses very often form symbiotic associations with Neotyphodium/Epichloë endophytic fungi. These endophytes often allow the host grass to be protected from different pathogens. However, there is little known about the mechanisms of such endophyte influence on the host. Thus, the purpose of this research was to examine the effect of the N. lolii endophyte on the total production of phenolic compounds, VOCs emission and the resistance of three perennial ryegrass genotypes infected by pathogenic Fusarium poae. Analyses of total phenolics content were performed in control (not inoculated) and inoculated plants after 1, 2, 3, 4, 5, and 6 days (DAI) and for VOCs after 0, 3, 6 and 12 DAI. The presence of endophytes significantly reduced the disease index in two of the three genotypes relative to that in E-. Plants infected by N. lolii exhibited higher production of phenolics relative to the E- plants. The highest amounts of phenolics were observed on the second and sixth DAI. Genotype Nl22 showed the strongest effect of the endophyte on the production of phenolics, which increased by over 61%. Both the endophyte infected and non-infected plants emitted most abundantly two GLVs ((Z)-3-hexenal, (Z)-3-hexen-1-yl acetate), three terpenes (linalool, (Z)-ocimene, β-caryophyllene) and three shikimic acid pathway derivatives (benzyl acetate, indole, and methyl salicylate). The endophyte presence and the intervals of VOCs detection were a highly significant source of variation for all emitted volatiles (P<0.001). The genotype of the perennial ryegrass significantly affected only the emission of methyl salicylate (P<0.05) and β-caryophyllene (P<0.05). Most of the VOCs ((Z)-3-hexen-1-yl acetate, (Z)-3-hexenal, linalool and methyl salicylate) reached their highest levels of emission on the sixth DAI, when averaged over genotypes and endophyte status. The results highlight the role of Neotyphodium spp. in the mediation of quadro-trophic interactions among plants, symbiotic

  11. Association between feeding perennial ryegrass (Lolium perenne cultivar Grasslands impact) containing high concentrations of ergovaline, and health and productivity in a herd of lactating dairy cows.

    PubMed

    Lean, I J

    2001-04-01

    Perennial ryegrasses are frequently infected with fungal endophyte (Neotyphodium lolii) to increase the resistance of the plant to insect damage. Unfortunately, a side effect of endophyte infection can be the production of alkaloids, including Lolitrem B and ergovaline, that produce toxic effects in animals. A significant 4.6 litre decrease in milk production in a herd of Holstein-Friesian dairy cows was associated with high concentrations of ergovaline in ryegrass silage. Simultaneously, milk SCC increased significantly over a comparable period and reproductive performance declined. Body condition score and coat condition of cows were adversely affected. Unique aspects of this Case report include; very stable production of the herd over a period of years before and after cessation of feeding silage containing high concentrations of ergovaline; the presence of high concentrations of ergovaline in the silage; and a controlled diet that reduced the risks of variation in feed availability and other sources of toxins. Veterinarians and other farm advisors should be aware of the potential for negative effects on animal health and production of fungal endophyte and the potential for Neotyphodium lolii to produce ergovaline. PMID:11349413

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  13. THE PHOTOSYNTHETIC RESPONSE OF THE PERENNIAL RYEGRASS (LOLIUM PERENNE) IN ITS FIFTH YEAR OF FREE-AIR CO{sub 2} ENRICHMENT (FACE) AT ESCHIKON, SWITZERLAND

    SciTech Connect

    ANDERSON,J.P.; LONG,STEPHEN,P.; WILLIAMS,J.

    1998-12-31

    Stands of Ryegrass (Lolium perenne L. cv.Bastion) were grown in the field at ambient or elevated (600 {micro}mol mol{sup {minus}1}) [CO{sub 2}], high (560 kg Ha{sup {minus}1} y{sup {minus}1}) or low (140 kg Ha{sup {minus}1} y{sup {minus}1}) nitrogen addition and were harvested five times a year during the growing season. The plants were sown during 1992, additional plots being sown during 1995. These were in their fifth year and second year of growth respectively. Exposure to elevated [CO{sub 2}] was carried out with a Free-Air CO{sub 2} Enrichment (FACE) system which provides the most realistic system of fumigation currently available. Elevated [CO{sub 2}] increased diurnal CO{sub 2} uptake by between 40 to 83% while reducing stomatal conductance by between 1 and 38% in all of the 1992 grown plants measured at high [CO{sub 2}]. Analysis of the A/c{sub i} response of 1992 grown plants showed no acclimation of the photosynthetic apparatus in response to elevated [CO{sub 2}]--both V{sub c,max} (a measure of the maximum in vivo rate of carboxylation) and J{sub max} (a measure of the maximum capacity for the regeneration of RuBP) showed no significant change during any of the periods of regrowth. In contrast the leaves of 1995 grown plants, appeared to be experiencing an acclimatory change in their photosynthetic apparatus in response to elevated [CO{sub 2}]. However, this negative response seemed to be removed directly after a harvest when the source:sink balance had increased. The apparent lack of an acclimatory response after almost 5 years of growth at elevated [CO{sub 2}], suggests that L. perenne may be close to achieving the appropriate photosynthetic adjustments which would allow it to attain a significantly higher photosynthetic potential.

  14. The photosynthetic response of the perennial ryegrass (Lolium perenne) in its fifth year of free-air CO(sub 2) enrichment (FACE) at Eschikon, Switzerland

    SciTech Connect

    Anderson, J.P.; Long, S.P.; Williams, J.

    1998-12-31

    Stands of Ryegrass (Lolium perenne L. cv.Bastion) were grown in the field at ambient or elevated (600 {micro}mol mol{sup {minus}1}) [CO{sub 2}], high (560 kg Ha{sup {minus}1} y{sup {minus}1}) or low (140 kg Ha{sup {minus}1} y{sup {minus}1}) nitrogen addition and were harvested five times a year during the growing season. The plants were sown during 1992, additional plots being sown during 1995. These were in their fifth year and second year of growth respectively. Exposure to elevated [CO{sub 2}] was carried out with a Free-Air CO{sub 2} Enrichment (FACE) system which provides the most realistic system of fumigation currently available. Elevated [CO{sub 2}] increased diurnal CO{sub 2} uptake by between 40 to 83% while reducing stomatal conductance by between 1 and 38% in all of the 1992 grown plants measured at high [CO{sub 2}]. Analysis of the A/c{sub i} response of 1992 grown plants showed no acclimation of the photosynthetic apparatus in response to elevated [CO{sub 2}] - both V{sub c,max} (a measure of the maximum in vivo rate of carboxylation) and J{sub max} (a measure of the maximum capacity for the regeneration of RuBP) showed no significant change during any of the periods of regrowth. In contrast the leaves of 1995 grown plants, appeared to be experiencing an acclimatory change in their photosynthetic apparatus in response to elevated [CO{sub 2}]. However, this negative response seemed to be removed directly after a harvest when the source:sink balance had increased. The apparent lack of an acclimatory response after almost 5 years of growth at elevated [CO{sub 2}], suggests that L. perenne may be close to achieving the appropriate photosynthetic adjustments which would allow it to attain a significantly higher photosynthetic potential.

  15. Mapping and comparative analysis of QTL for crown rust resistance in an Italian x perennial ryegrass population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crown rust (Puccinia coronata f.sp. lolli) is a serious fungal foliar disease of perennial ryegrass (Lolium perenne L.) and Italian ryegrass (L. multiflorum L.) which are important forage and turf species. A number of quantitative trait loci (QTL) for crown rust resistance were previously identifie...

  16. Candidate gene association mapping for winter survival and spring regrowth in perennial ryegrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Perennial ryegrass (Lolium perenne L.) is a widely cultivated cool-season grass species because of its high quality for forage and turf. Susceptibility to freezing damage limits its further use in temperate zones. The objective of this study was to identify candidate genes significantly associated w...

  17. Vasoconstrictive responses of lambs grazing endophyte-infected perennial ryegrass paddocks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The AR6 novel endophyte (Neotyphodium lolii) produces ergovaline that deters against the African black beetle, but also causes vasoconstriction that restricts an animal’s ability to dissipate body heat. An experiment was conducted with 3, 0.10-ha pastures of ‘Extreme’ perennial ryegrass (Lolium per...

  18. Fructan synthesis, accumulation and polymer traits. II. Fructan pools in populations of perennial ryegrass (Lolium perenne L.) with variation for water-soluble carbohydrate and candidate genes were not correlated with biosynthetic activity and demonstrated constraints to polymer chain extension

    PubMed Central

    Gallagher, Joe A.; Cairns, Andrew J.; Thomas, David; Timms-Taravella, Emma; Skøt, Kirsten; Charlton, Adam; Williams, Peter; Turner, Lesley B.

    2015-01-01

    Differences have been shown between ryegrass and fescue within the Festulolium subline introgression family for fructan synthesis, metabolism, and polymer-size traits. It is well-established that there is considerable variation for water-soluble carbohydrate and fructan content within perennial ryegrass. However there is much still to be discovered about the fructan polymer pool in this species, especially in regard to its composition and regulation. It is postulated that similar considerable variation for polymer traits may exist, providing useful polymers for biorefining applications. Seasonal effects on fructan content together with fructan synthesis and polymer-size traits have been examined in diverse perennial ryegrass material comprising contrasting plants from a perennial ryegrass F2 mapping family and from populations produced by three rounds of phenotypic selection. Relationships with copy number variation in candidate genes have been investigated. There was little evidence of any variation in fructan metabolism across this diverse germplasm under these conditions that resulted in substantial differences in the complement of fructan polymers present in leaf tissue at high water-soluble carbohydrate concentrations. The importance of fructan synthesis during fructan accumulation was unclear as fructan content and polymer characteristics in intact plants during the growing season did not reflect the capacity for de novo synthesis. However, the retention of fructan in environmental conditions favoring high sink/low source demand may be an important component of the high sugar trait and the roles of breakdown and turnover are discussed. PMID:26528321

  19. Association of freezing tolerance to LpCBFIIIb and LpCBFIIIc gene polymorphism in perennial ryegrass accessions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    CBF/DREB related genes are considered important genes for regulation of abiotic stress in plants. In this study, CBF/DREB genes in perennial ryegrass (Lolium perenne L.), also known as LpCBF genes, were resequenced from several cultivated and landrace plants from a worldwide collection. The same pla...

  20. Forages and pastures symposium: fungal endophytes of tall fescue and perennial ryegrass: pasture friend or foe?

    PubMed

    Young, C A; Hume, D E; McCulley, R L

    2013-05-01

    Tall fescue [Lolium arundinaceum (Schreb.) Darbysh. syn. Festuca arundinacea Schreb.] and perennial ryegrass (Lolium perenne L.) are important perennial forage grasses utilized throughout the moderate- to high-rainfall temperate zones of the world. These grasses have coevolved with symbiotic fungal endophytes (Epichloë/Neotyphodium spp.) that can impart bioactive properties and environmental stress tolerance to the grass compared with endophyte-free individuals. These endophytes have proven to be very important in pastoral agriculture in the United States, New Zealand, and Australia, where forage grasses are the principal feed for grazing ruminants. In this review, we describe the biology of these grass-endophyte associations and implications for the livestock industries that are dependent on these forages. Endophyte alkaloid production is put in context with endophyte diversity, and we illustrate how this has facilitated utilization of grasses infected with different endophyte strains that reduce livestock toxicity issues. Utilization of tall fescue and use of perennial ryegrass in the United States, New Zealand, and Australia are compared, and management strategies focused predominantly on the success of endophyte-infected perennial ryegrass in New Zealand and Australia are discussed. In addition, we consider the impact of grass-endophyte associations on the sustainability of pasture ecosystems and their likely response to future changes in climate. PMID:23307839

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

    SciTech Connect

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

    1991-04-01

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

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

    PubMed

    Marley, Christina L; Fychan, Rhun; Davies, John W; Scollan, Nigel D; Richardson, R Ian; Theobald, Vince J; Genever, Elizabeth; Forbes, Andy B; Sanderson, Ruth

    2014-01-01

    An experiment investigated whether the inclusion of chicory (Cichorium intybus) in swards grazed by beef steers altered their performance, carcass characteristics or parasitism when compared to steers grazing perennial ryegrass (Lolium perenne). Triplicate 2-ha plots were established with a chicory/ryegrass mix or ryegrass control. Forty-eight Belgian Blue-cross steers were used in the first grazing season and a core group (n = 36) were retained for finishing in the second grazing season. The experiment comprised of a standardisation and measurement period. During standardisation, steers grazed a ryegrass/white clover pasture as one group. Animals were allocated to treatment on the basis of liveweight, body condition and faecal egg counts (FEC) determined 7 days prior to the measurement period. The measurement period ran from 25 May until 28 September 2010 and 12 April until 11 October 2011 in the first and second grazing year. Steers were weighed every 14 days at pasture or 28 days during housing. In the first grazing year, faecal samples were collected for FEC and parasite cultures. At the end of the first grazing year, individual blood samples were taken to determine O. ostertagi antibody and plasma pepsinogen levels. During winter, animals were housed as one group and fed silage. In the second grazing year, steers were slaughtered when deemed to reach fat class 3. Data on steer performance showed no differences in daily live-weight gain which averaged 1.04 kg/day. The conformation, fat grade and killing out proportion of beef steers grazing chicory/ryegrass or ryegrass were not found to differ. No differences in FEC, O. ostertagi antibody or plasma pepsinogen levels of beef steers grazing either chicory/ryegrass or ryegrass were observed. Overall, there were no detrimental effects of including chicory in swards grazed by beef cattle on their performance, carcass characteristics or helminth parasitism, when compared with steers grazing ryegrass. PMID:24489708

  3. Effects of Chicory/Perennial Ryegrass Swards Compared with Perennial Ryegrass Swards on the Performance and Carcass Quality of Grazing Beef Steers

    PubMed Central

    Marley, Christina L.; Fychan, Rhun; Davies, John W.; Scollan, Nigel D.; Richardson, R. Ian; Theobald, Vince J.; Genever, Elizabeth; Forbes, Andy B.; Sanderson, Ruth

    2014-01-01

    An experiment investigated whether the inclusion of chicory (Cichorium intybus) in swards grazed by beef steers altered their performance, carcass characteristics or parasitism when compared to steers grazing perennial ryegrass (Lolium perenne). Triplicate 2-ha plots were established with a chicory/ryegrass mix or ryegrass control. Forty-eight Belgian Blue-cross steers were used in the first grazing season and a core group (n = 36) were retained for finishing in the second grazing season. The experiment comprised of a standardisation and measurement period. During standardisation, steers grazed a ryegrass/white clover pasture as one group. Animals were allocated to treatment on the basis of liveweight, body condition and faecal egg counts (FEC) determined 7 days prior to the measurement period. The measurement period ran from 25 May until 28 September 2010 and 12 April until 11 October 2011in the first and second grazing year. Steers were weighed every 14 days at pasture or 28 days during housing. In the first grazing year, faecal samples were collected for FEC and parasite cultures. At the end of the first grazing year, individual blood samples were taken to determine O. ostertagi antibody and plasma pepsinogen levels. During winter, animals were housed as one group and fed silage. In the second grazing year, steers were slaughtered when deemed to reach fat class 3. Data on steer performance showed no differences in daily live-weight gain which averaged 1.04 kg/day. The conformation, fat grade and killing out proportion of beef steers grazing chicory/ryegrass or ryegrass were not found to differ. No differences in FEC, O. ostertagi antibody or plasma pepsinogen levels of beef steers grazing either chicory/ryegrass or ryegrass were observed. Overall, there were no detrimental effects of including chicory in swards grazed by beef cattle on their performance, carcass characteristics or helminth parasitism, when compared with steers grazing ryegrass. PMID:24489708

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

    PubMed

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

    2008-11-01

    Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) are cyclic nitramines used as explosives. Their ecotoxicities have been characterized incompletely and little is known about their accumulation potential in soil organisms. We assessed the toxicity and uptake of these explosives in perennial ryegrass Lolium perenne L. exposed in a Sassafras sandy loam (SSL) or in a sandy soil (DRDC, CL-20 only) containing contrasting clay contents (11% and 0.3%, respectively). A 21-d exposure to RDX, HMX or CL-20 in either soil had no adverse effects on ryegrass growth. RDX and HMX were translocated to ryegrass shoots, with bioconcentration factors (BCF) of up to 15 and 11, respectively. In contrast, CL-20 was taken up by the roots (BCF up to 19) with no translocation to the shoots. These studies showed that RDX, HMX, and CL-20 can accumulate in plants and may potentially pose a risk of biomagnification across the food chain. PMID:18358578

  5. Population Structure, Genetic Variation, and Linkage Disequilibrium in Perennial Ryegrass Populations Divergently Selected for Freezing Tolerance

    PubMed Central

    Kovi, Mallikarjuna Rao; Fjellheim, Siri; Sandve, Simen R.; Larsen, Arild; Rudi, Heidi; Asp, Torben; Kent, Matthew Peter; Rognli, Odd Arne

    2015-01-01

    Low temperature is one of the abiotic stresses seriously affecting the growth of perennial ryegrass (Lolium perenne L.), and freezing tolerance is a complex trait of major agronomical importance in northern and central Europe. Understanding the genetic control of freezing tolerance would aid in the development of cultivars of perennial ryegrass with improved adaptation to frost. The plant material investigated in this study was an experimental synthetic population derived from pair-crosses among five European perennial ryegrass genotypes, representing adaptations to a range of climatic conditions across Europe. A total number of 80 individuals (24 of High frost [HF]; 29 of Low frost [LF], and 27 of Unselected [US]) from the second generation of the two divergently selected populations and an unselected (US) control population were genotyped using 278 genome-wide SNPs derived from perennial ryegrass transcriptome sequences. Our studies investigated the genetic diversity among the three experimental populations by analysis of molecular variance and population structure, and determined that the HF and LF populations are very divergent after selection for freezing tolerance, whereas the HF and US populations are more similar. Linkage disequilibrium (LD) decay varied across the seven chromosomes and the conspicuous pattern of LD between the HF and LF population confirmed their divergence in freezing tolerance. Furthermore, two Fst outlier methods; finite island model (fdist) by LOSITAN and hierarchical structure model using ARLEQUIN, both detected six loci under directional selection. These outlier loci are most probably linked to genes involved in freezing tolerance, cold adaptation, and abiotic stress. These six candidate loci under directional selection for freezing tolerance might be potential marker resources for breeding perennial ryegrass cultivars with improved freezing tolerance. PMID:26617611

  6. Productivity and persistence of multi-cultivar perennial ryegrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Perennial ryegrass is an exceptionally high quality forage grass but its use in the northeast has been limited because it is typically not as winter hardy as other perennial forage grasses. This can be a particularly difficult problem for winters such as 2013-2014 which experienced wide-spread and l...

  7. Effects of accelerated aging on italian ryegrass (Lolium multiflorum) seed germination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Italian ryegrass (Lolium multiflorum) is a productive, high quality cool-season forage that is overseeded in warm-season pastures for winter and early spring grazing. However, in some pastures and croplands it can be a serious weed. Italian ryegrass does not form an extensive seed bank and the see...

  8. Candidate gene association mapping for winter survival and spring regrowth in perennial ryegrass.

    PubMed

    Yu, Xiaoqing; Pijut, Paula M; Byrne, Stephen; Asp, Torben; Bai, Guihua; Jiang, Yiwei

    2015-06-01

    Perennial ryegrass (Lolium perenne L.) is a widely cultivated cool-season grass species because of its high quality for forage and turf. Susceptibility to freezing damage limits its further use in temperate zones. The objective of this study was to identify candidate genes significantly associated with winter survival and spring regrowth in a global collection of 192 perennial ryegrass accessions. Significant differences in winter survival (WS), percentage of canopy green cover (CGC), chlorophyll index (Chl), and normalized difference vegetation index (NDVI) were found among accessions. After controlling population structure, LpLEA3 encoding a late embryogenesis abundant group 3 protein and LpCAT encoding a catalase were associated with CGC and Chl, while LpMnSOD encoding a magnesium superoxide dismutase and LpChl Cu-ZnSOD encoding a chlorophyll copper-zinc superoxide dismutase were associated with NDVI or Chl. Significant association was also discovered between C-repeat binding factor LpCBF1b and WS. Three sequence variations identified in LpCAT, LpMnSOD, and LpChl Cu-ZnSOD were synonymous substitutions, whereas one pair of adjacent single nucleotide polymorphisms (SNPs) in LpLEA3 and one SNP in LpCBF1b resulted in amino acid change. The results demonstrated that allelic variation in LpLEA3 and LpCBF1b was closely related to winter survival and spring regrowth in perennial ryegrass. PMID:25900564

  9. Development of a DNA Sequence-Based Multiplex Test for Rapid Differentiation of Ryegrass Growth Types

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Annual (Lolium multiflorum Lam.) and perennial (Lolium perenne L.) ryegrasses are two common forage species in temperate regions. Identifying annual ryegrass contamination in perennial ryegrass seed lots has been of major interest in the seed industry for many years. The objective of our work over t...

  10. Using advances in plant genomics to develop a DNA-based test to benefit the ryegrass seed industry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Annual (Lolium multiflorum Lam.) and perennial (Lolium perenne L.) ryegrasses are two common forage species in temperate regions. Identifying annual ryegrass contamination in perennial ryegrass seed lots has been of major interest in the seed industry for many years. The objective of our work over t...

  11. Identification of Anguina funesta from annual ryegrass (Lolium multiflorum) seed lots in Oregon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2010, seed galls containing Anguina sp. were isolated from 14 annual ryegrass (Lolium multiflorum) seed lots submitted for phytosanitary testing. To identify the species present, the ITS1 region of the ribosomal DNA of the nematodes from the seed lots was analyzed using a PCR-RFLP method (11). ...

  12. Interrelationships between Acremonium lolii, Peramine, and Lolitrem B in Perennial Ryegrass

    PubMed Central

    Ball, O. J.; Prestidge, R. A.; Sprosen, J. M.

    1995-01-01

    Perennial ryegrass (Lolium perenne L.) is commonly infected with the endophytic fungus Acremonium lolii in a mutualistic relationship. The fungus produces a number of alkaloids, some of which are responsible for causing livestock disorders and/or for conferring insect resistance to the host grass. Little is known about the interrelationship between fungal growth and alkaloid production in the ryegrass plant and how this varies throughout the year. The concentrations of A. lolii and two of its alkaloid metabolites, lolitrem B and peramine, were monitored in basal (mainly leaf sheath) and upper (mainly leaf blade) parts of 17 endophyte-infected ryegrass plants on a monthly basis for 1 year. A. lolii, lolitrem B, and peramine concentrations were lowest in winter. The highest A. lolii concentrations were recorded in early summer, which coincided with the development of plant reproductive structures. Lolitrem B concentrations were highest from summer to early autumn and were consistently highest in the basal part of the plant. Peramine concentrations were generally highest in the upper part of the plant. Individual plants contained different levels of A. lolii, lolitrem B and peramine. These differences were generally maintained throughout the year. Although data for each month were variable, regression analyses showed that yearly mean concentrations of lolitrem B and peramine in individual plants were closely related to, and therefore probably largely determined by, yearly mean concentrations of A. lolii. PMID:16535001

  13. Italian ryegrass (Lolium multiflorum) and corn (Zea mays)competition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Italian ryegrass is an annual/biennial grass that is typically used as a pasture crop or a cover crop along roadsides, rights-of-way, and industrial areas. Glyphosate-resistant (GR) Italian ryegrass populations have been documented around the world, mostly in orchard and vineyard situations. The fir...

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

    PubMed Central

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

    2015-01-01

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

  15. Global transcriptome changes in perennial ryegrass during early infection by pink snow mould.

    PubMed

    Kovi, Mallikarjuna Rao; Abdelhalim, Mohamed; Kunapareddy, Anil; Ergon, Åshild; Tronsmo, Anne Marte; Brurberg, May Bente; Hofgaard, Ingerd Skow; Asp, Torben; Rognli, Odd Arne

    2016-01-01

    Lack of resistance to pink snow mould (Microdochium nivale) is a major constraint for adaptation of perennial ryegrass (Lolium perenne L.) to continental regions with long-lasting snow cover at higher latitudes. Almost all investigations of genetic variation in resistance have been performed using cold acclimated plants. However, there may be variation in resistance mechanisms that are functioning independently of cold acclimation. In this study our aim was to identify candidate genes involved in such resistance mechanisms. We first characterized variation in resistance to M. nivale among non-acclimated genotypes from the Norwegian cultivar 'Fagerlin' based on relative regrowth and fungal quantification by real-time qPCR. One resistant and one susceptible genotype were selected for transcriptome analysis using paired-end sequencing by Illumina Hiseq 2000. Transcriptome profiles, GO enrichment and KEGG pathway analysis indicate that defense response related genes are differentially expressed between the resistant and the susceptible genotype. A significant up-regulation of defense related genes, as well as genes involved in cell wall cellulose metabolic processes and aryl-alcohol dehydrogenase (NADP+) activity, was observed in the resistant genotype. The candidate genes identified in this study might be potential molecular marker resources for breeding perennial ryegrass cultivars with improved resistance to pink snow mould. PMID:27346054

  16. Global transcriptome changes in perennial ryegrass during early infection by pink snow mould

    PubMed Central

    Kovi, Mallikarjuna Rao; Abdelhalim, Mohamed; Kunapareddy, Anil; Ergon, Åshild; Tronsmo, Anne Marte; Brurberg, May Bente; Hofgaard, Ingerd Skow; Asp, Torben; Rognli, Odd Arne

    2016-01-01

    Lack of resistance to pink snow mould (Microdochium nivale) is a major constraint for adaptation of perennial ryegrass (Lolium perenne L.) to continental regions with long-lasting snow cover at higher latitudes. Almost all investigations of genetic variation in resistance have been performed using cold acclimated plants. However, there may be variation in resistance mechanisms that are functioning independently of cold acclimation. In this study our aim was to identify candidate genes involved in such resistance mechanisms. We first characterized variation in resistance to M. nivale among non-acclimated genotypes from the Norwegian cultivar ‘Fagerlin’ based on relative regrowth and fungal quantification by real-time qPCR. One resistant and one susceptible genotype were selected for transcriptome analysis using paired-end sequencing by Illumina Hiseq 2000. Transcriptome profiles, GO enrichment and KEGG pathway analysis indicate that defense response related genes are differentially expressed between the resistant and the susceptible genotype. A significant up-regulation of defense related genes, as well as genes involved in cell wall cellulose metabolic processes and aryl-alcohol dehydrogenase (NADP+) activity, was observed in the resistant genotype. The candidate genes identified in this study might be potential molecular marker resources for breeding perennial ryegrass cultivars with improved resistance to pink snow mould. PMID:27346054

  17. Exogenous glycinebetaine alleviates the detrimental effect of Cd stress on perennial ryegrass.

    PubMed

    Lou, Yanhong; Yang, Yong; Hu, Longxing; Liu, Hongmei; Xu, Qingguo

    2015-08-01

    Glycinebetaine (GB) is an important organic osmolyte that accumulates in many plant species in response to abiotic stresses including heavy metals. The objective of this study was to investigate whether exogenous GB would ameliorate the adverse effect of cadmium (Cd) stress on perennial ryegrass (Lolium perenne). Fifty-three days old seedlings were exposed to hydroponic culture for 7 days with six treatments: T1 (control), T2 (0 mM Cd + 20 mM GB), T3 (0 mM Cd + 50 mM GB), T4 (0.5 mM Cd + 0 mM GB), T5 (0.5 mM Cd + 20 mM GB), T6 (0.5 mM Cd + 50 mM GB). Cd stress resulted in a remarkable decrease in turf quality, vertical shoot growth rate (VSGR), normalized relative transpiration (NRT) and Chlorophyll (Chl) content; with significant increases in electric conductivity (EL), malondialdehyde (MDA) content, superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) activity, oxalic and tartaric acid content. Exogenous application of GB decreased EL and MDA content in Cd stressed plants, and increased turf quality, VSGR, NRT, Chl content, SOD, CAT, POD activity, oxalic, tartaric acid content, and the gene expression level of SOD and POD when compared with Cd stressed without GB. Perennial ryegrass with 20 mM GB application suppressed the Cd accumulation in both shoots and roots. A lower translocation factor of Cd was found in GB treated plants than non-GB treated plants, and the lowest translocation factor was observed in the 20 mM GB application. These results suggested that GB could alleviate the detrimental effect of Cd on perennial ryegrass and the amelioration was mainly related to the elevation in SOD, CAT, and POD at enzyme and gene expression levels, which reduced Cd content in shoots and improved cell membrane stability by reducing oxidation of membrane lipids. These findings lead us to conclude that application of GB with 20 mM is the best strategy to ameliorate the detrimental impacts of Cd stress on perennial ryegrass. PMID:26135319

  18. Towards a better understanding of the generation of fructan structure diversity in plants: molecular and functional characterization of a sucrose:fructan 6-fructosyltransferase (6-SFT) cDNA from perennial ryegrass (Lolium perenne)

    PubMed Central

    Lasseur, Bertrand; Lothier, Jérémy; Wiemken, Andres; Van Laere, André; Morvan-Bertrand, Annette; den Ende, Wim Van; Prud'homme, Marie-Pascale

    2011-01-01

    The main storage compounds in Lolium perenne are fructans with prevailing β(2–6) linkages. A cDNA library of L. perenne was screened using Poa secunda sucrose:fructan 6-fructosyltransferase (6-SFT) as a probe. A full-length Lp6-SFT clone was isolated as shown by heterologous expression in Pichia pastoris. High levels of Lp6-SFT transcription were found in the growth zone of elongating leaves and in mature leaf sheaths where fructans are synthesized. Upon fructan synthesis induction, Lp6-SFT transcription was high in mature leaf blades but with no concomitant accumulation of fructans. In vitro studies with the recombinant Lp6-SFT protein showed that both 1-kestotriose and 6G-kestotriose acted as fructosyl acceptors, producing 1- and 6-kestotetraose (bifurcose) and 6G,6-kestotetraose, respectively. Interestingly, bifurcose formation ceased and 6G,6-kestotetraose was formed instead, when recombinant fructan:fructan 6G-fructosyltransferase (6G-FFT) of L. perenne was introduced in the enzyme assay with sucrose and 1-kestotriose as substrates. The remarkable absence of bifurcose in L. perenne tissues might be explained by a higher affinity of 6G-FFT, as compared with 6-SFT, for 1-kestotriose, which is the first fructan formed. Surprisingly, recombinant 6-SFT from Hordeum vulgare, a plant devoid of fructans with internal glucosyl residues, also produced 6G,6-kestotetraose from sucrose and 6G-kestotriose. In the presence of recombinant L. perenne 6G-FFT, it produced 6G,6-kestotetraose from 1-kestotriose and sucrose, like L. perenne 6-SFT. Thus, we demonstrate that the two 6-SFTs have close catalytic properties and that the distinct fructans formed in L. perenne and H. vulgare can be explained by the presence of 6G-FFT activity in L. perenne and its absence in H. vulgare. PMID:21196473

  19. Lolitrem B residue in fat tissues of cattle consuming endophyte-infected perennial ryegrass straw.

    PubMed

    Miyazaki, Shigeru; Ishizaki, Ikumi; Ishizaka, Masumi; Kanbara, Tadashi; Ishiguro-Takeda, Yuriko

    2004-07-01

    Lolitrems are neurotoxins found in endophyte-infected perennial ryegrass. Lolitrems, primarily lolitrem B, are the causative agents of ryegrass staggers in livestock. To guarantee the safety of meat produced from cattle consuming endophyte-infected perennial ryegrass, lolitrem B concentrations in tissues of Japanese Black cattle were determined using high-performance liquid chromatography. Lolitrem B was not detected in muscle, liver, kidney, or cerebrum of a Japanese Black cow with signs of ryegrass staggers. In contrast, perirenal fat contained 210 ppb lolitrem B. Three cows that received half as much perennial ryegrass straw as the cow with ryegrass staggers showed no clinical signs of ryegrass staggers. However, low concentrations of lolitrem B (less than 150 ppb) were detected in their fat tissue. These observations indicate that human exposure to the neurotoxic effect of lolitrem B through beef is unlikely. The amount of lolitrem B consumed by cattle can be estimated by the determination of lolitrem B in fat tissue. PMID:15305749

  20. Spatial patterns of ergot and quantification of sclerotia in perennial ryegrass seed fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ergot, caused by Claviceps purpurea, is a major disease of perennial ryegrass grass grown for seed in eastern Oregon. The objective of this research was to quantify and describe the spatial patterns of ergot severity in each of three 50 ha commercial fields of perennial ryegrass grown for seed in 20...

  1. Functional characterization and hormonal regulation of the PHEOPHYTINASE gene LpPPH controlling leaf senescence in perennial ryegrass.

    PubMed

    Zhang, Jing; Yu, Guohui; Wen, Wuwu; Ma, Xiqing; Xu, Bin; Huang, Bingru

    2016-02-01

    Chlorophyll (Chl) degradation occurs naturally during leaf maturation and senescence, and can be induced by stresses, both processes involving the regulation of plant hormones. The objective of this study was to determine the functional roles and hormonal regulation of a gene encoding pheophytin pheophorbide hydrolyase (PPH) that catabolizes Chl degradation during leaf senescence in perennial grass species. A PPH gene, LpPPH, was cloned from perennial ryegrass (Lolium perenne L.). LpPPH was localized in the chloroplast. Overexpressing LpPPH accelerated Chl degradation in wild tobacco, and rescued the stay-green phenotype of the Arabidopsis pph null mutant. The expression level of LpPPH was positively related to the extent of leaf senescence. Exogenous application of abscisic acid (ABA) and ethephon (an ethylene-releasing agent) accelerated the decline in Chl content in leaves of perennial ryegrass, whereas cytokinin (CK) and aminoethoxyvinylglycine (AVG; an ethylene biosynthesis inhibitor) treatments suppressed leaf senescence, corresponding to the up- or down-regulation of LpPPH expression. The promoters of five orthologous PPH genes were predicted to share conserved cis-elements potentially recognized by transcription factors in the ABA and CK pathways. Taken together, the results suggested that LpPPH-mediated Chl breakdown could be regulated positively by ABA and ethylene, and negatively by CK, and LpPPH could be a direct downstream target gene of transcription factors in the ABA and CK signaling pathways. PMID:26643195

  2. Functional characterization and hormonal regulation of the PHEOPHYTINASE gene LpPPH controlling leaf senescence in perennial ryegrass

    PubMed Central

    Zhang, Jing; Yu, Guohui; Wen, Wuwu; Ma, Xiqing; Xu, Bin; Huang, Bingru

    2016-01-01

    Chlorophyll (Chl) degradation occurs naturally during leaf maturation and senescence, and can be induced by stresses, both processes involving the regulation of plant hormones. The objective of this study was to determine the functional roles and hormonal regulation of a gene encoding pheophytin pheophorbide hydrolyase (PPH) that catabolizes Chl degradation during leaf senescence in perennial grass species. A PPH gene, LpPPH, was cloned from perennial ryegrass (Lolium perenne L.). LpPPH was localized in the chloroplast. Overexpressing LpPPH accelerated Chl degradation in wild tobacco, and rescued the stay-green phenotype of the Arabidopsis pph null mutant. The expression level of LpPPH was positively related to the extent of leaf senescence. Exogenous application of abscisic acid (ABA) and ethephon (an ethylene-releasing agent) accelerated the decline in Chl content in leaves of perennial ryegrass, whereas cytokinin (CK) and aminoethoxyvinylglycine (AVG; an ethylene biosynthesis inhibitor) treatments suppressed leaf senescence, corresponding to the up- or down-regulation of LpPPH expression. The promoters of five orthologous PPH genes were predicted to share conserved cis-elements potentially recognized by transcription factors in the ABA and CK pathways. Taken together, the results suggested that LpPPH-mediated Chl breakdown could be regulated positively by ABA and ethylene, and negatively by CK, and LpPPH could be a direct downstream target gene of transcription factors in the ABA and CK signaling pathways. PMID:26643195

  3. Plant uptake and phytotoxicity of decabromodiphenyl ether (BDE-209) in ryegrass (Lolium perenne L).

    PubMed

    Xie, Xianchuan; Qian, Yan; Xue, Yingang; He, Huan; Wei, Dongyang

    2013-10-01

    The plant uptake and phytotoxicity of decabromodiphenyl ether (BDE-209) in ryegrass (Lolium perenne L) seedlings were investigated. Results showed that ryegrass could take up BDE-209 from the contaminated soils and most of the BDE-209 in plants is located in roots, indicating that BDE-209 has low root-to-shoot translocation. Except for about 35% inhibition of root growth and about 30% decrease of the chlorophyll b and carotenoid contents of leaves, no visual toxicity symptoms were observed in seedlings grown even at a high concentration of 100 mg kg(-1). BDE-209 exposure significantly induced the generation of the superoxide radical (O2˙(-)) and malondialdehyde (MDA) in ryegrass leaves. With the increase of BDE-209 concentration, the activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), and glutathione-S-transferase (GST) were significantly changed, and the ratio of reduced glutathione to oxidized glutathione (GSH/GSSG) was also significantly reduced. Results suggested that BDE-209 exposure could cause oxidative stress and damage, which may play an important role in the phytotoxicity of BDE-209 in ryegrass seedlings. PMID:23999790

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

    NASA Astrophysics Data System (ADS)

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

    2014-11-01

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

  5. Isolation of prostrate turfgrass mutants via screening of dwarf phenotype and characterization of a perennial ryegrass prostrate mutant.

    PubMed

    Chen, Junmei; Thammina, Chandra; Li, Wei; Yu, Hao; Yer, Huseyin; El-Tanbouly, Rania; Marron, Manon; Katin-Grazzini, Lorenzo; Chen, Yongqin; Inguagiato, John; McAvoy, Richard J; Guillard, Karl; Zhang, Xian; Li, Yi

    2016-01-01

    Prostrate turf varieties are desirable because of their increased low mowing tolerance, heat resistance, traffic resistance and ground coverage compared with upright varieties. Mutation breeding may provide a powerful tool to create prostrate varieties, but there are no simple, straightforward methods to screen for such mutants. Elucidation of the molecular basis of the major 'green revolution' traits, dwarfism and semi-dwarfism, guided us to design a simple strategy for isolating dwarf mutants of perennial ryegrass (Lolium perenne L.). We have shown that gamma-ray-mediated dominant dwarf mutants can be easily screened for at the three-leaf stage. About 10% of dwarf mutant lines also displayed a prostrate phenotype at mature stages (>10 tillers). One prostrate line, Lowboy I, has been characterized in detail. Lowboy I had significantly shorter canopy, leaf blade and internode lengths compared with wild type. Lowboy I also exhibited greater tolerance to low mowing stress than wild type. Exogenous gibberellic acid (GA) restored Lowboy I to a wild-type phenotype, indicating that the dwarf and prostrate phenotypes were both due to GA deficiency. We further showed that phenotypes of Lowboy I were dominant and stably inherited through sexual reproduction. Prostrate turfgrass mutants are difficult to screen for because the phenotype is not observed at young seedling stages, therefore our method represents a simple strategy for easily isolating prostrate mutants. Furthermore, Lowboy I may provide an outstanding germplasm for breeding novel prostrate perennial ryegrass cultivars. PMID:26955481

  6. Isolation of prostrate turfgrass mutants via screening of dwarf phenotype and characterization of a perennial ryegrass prostrate mutant

    PubMed Central

    Chen, Junmei; Thammina, Chandra; Li, Wei; Yu, Hao; Yer, Huseyin; El-Tanbouly, Rania; Marron, Manon; Katin-Grazzini, Lorenzo; Chen, Yongqin; Inguagiato, John; McAvoy, Richard J.; Guillard, Karl; Zhang, Xian; Li, Yi

    2016-01-01

    Prostrate turf varieties are desirable because of their increased low mowing tolerance, heat resistance, traffic resistance and ground coverage compared with upright varieties. Mutation breeding may provide a powerful tool to create prostrate varieties, but there are no simple, straightforward methods to screen for such mutants. Elucidation of the molecular basis of the major ‘green revolution’ traits, dwarfism and semi-dwarfism, guided us to design a simple strategy for isolating dwarf mutants of perennial ryegrass (Lolium perenne L.). We have shown that gamma-ray-mediated dominant dwarf mutants can be easily screened for at the three-leaf stage. About 10% of dwarf mutant lines also displayed a prostrate phenotype at mature stages (>10 tillers). One prostrate line, Lowboy I, has been characterized in detail. Lowboy I had significantly shorter canopy, leaf blade and internode lengths compared with wild type. Lowboy I also exhibited greater tolerance to low mowing stress than wild type. Exogenous gibberellic acid (GA) restored Lowboy I to a wild-type phenotype, indicating that the dwarf and prostrate phenotypes were both due to GA deficiency. We further showed that phenotypes of Lowboy I were dominant and stably inherited through sexual reproduction. Prostrate turfgrass mutants are difficult to screen for because the phenotype is not observed at young seedling stages, therefore our method represents a simple strategy for easily isolating prostrate mutants. Furthermore, Lowboy I may provide an outstanding germplasm for breeding novel prostrate perennial ryegrass cultivars. PMID:26955481

  7. Prompt chlorophyll a fluorescence as a rapid tool for diagnostic changes in PSII structure inhibited by salt stress in Perennial ryegrass.

    PubMed

    Dąbrowski, P; Baczewska, A H; Pawluśkiewicz, B; Paunov, M; Alexantrov, V; Goltsev, V; Kalaji, M H

    2016-04-01

    Perennial ryegrass (Lolium perenne L.) is one of the most popular grass species in Europe. It is commonly used for establishing the lawns in urban areas, where the salt stress is one of the major environmental conditions limiting its growth. The basic aim of this study was the detailed in vivo analysis of the changes in photosynthetic efficiency, induced by salt stress, of two lawn varieties of Perennial ryegrass and to find out the variety of better properties to create lawn on the soils contaminated with salt. Two lawn varieties of L. perenne L. were used: Nira and Roadrunner. The salinization was applied 8 weeks after sowing by adding NaCl in water solution (0, 0.15, and 0.30 M). The measurements were carried out 8 times: 0, 24, 48, 96, 144, 192, 240 and 288 h after salinization. Our results revealed that the disturbance of PSII function could easily be estimated by measuring chlorophyll a fluorescence and analyzing that signal by JIP-test. Our work allowed to identify various limiting parameters of photosynthetic efficiency of perennial ryegrass lawn varieties grown under salt stress conditions. This knowledge can allow for selection of plants with a higher potential photosynthetic efficiency (vitality) during salt stress conditions, that can be used successfully neighboring roads, where salt is applied. PMID:26878219

  8. Effects of chlorsulfuron on diclofop-methyl toxicity to Italian ryegrass (Lolium multiflorum) and Italian ryegrass interference in wheat (triticum aestivum)

    SciTech Connect

    Liebl, R.A.

    1985-01-01

    Chlorsulfuron )2-chloro-N-(((4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino)carbonyl)benzenesulfonamide) and diclofop-methyl )methyl 2-(4-(2,4-dichlorophenoxy)phenoxy)propanoate) are herbicides used for the selective control of broadleaf and grassy weeds, respectively, in wheat (Triticum aestivum L.). The addition of chlorsulfuron (14.8 g ai/ha) to 0.90 kg ai/ha diclofop-methyl and applied postemergence reduced Italian ryegrass (Lolium multiflorum L.) control 27% and increased fresh weights over diclofop-methyl alone. Chlorsulfuron and diclofop-methyl were approximately 200 and 35%, respectively, more active on Italian ryegrass when applied pre-emergence compared to postemergence applications and responses of the combinations were additive. Although little movement of /sup 14/C-label occurred in either species, significantly more /sup 14/C-label translocated from the treated zone of Italian ryegrass. In metabolism studies, wheat was able to detoxify diclofop-methyl more rapidly than Italian ryegrass. In field interference studies, wheat grain yields were reduced an average of 4.2% for every 10 Italian ryegrass plants/m/sup 2/ because of decreased crop tillering. Italian ryegrass had net nitrate and potassium influx rates approximately 2-times greater than those for wheat when plants were growing in nutrient solution in the greenhouse.

  9. Genotypic variation in growth and metabolic responses of perennial ryegrass exposed to short-term waterlogging and submergence stress.

    PubMed

    Liu, Mingxi; Jiang, Yiwei

    2015-10-01

    Physiological mechanisms of waterlogging (WL) and submergence (SM) tolerance are not well understood in perennial grasses used for turf and forage. The objective of this study was to characterize growth, antioxidant activity and lipid peroxidation of perennial ryegrass (Lolium perenne) exposed to short-term WL and SM. 'Silver Dollar' (turf-type cultivar), 'PI418714' (wild accession), 'Kangaroo Valley' (forage-type cultivar) and 'PI231569' (unknown status) varying in growth habits and leaf texture were subjected to 7 d of WL and SM in a growth chamber. Plant height was unaffected by WL but was significantly reduced by SM for all grasses except PI418714. The SM treatment caused greater reductions in leaf chlorophyll and total carotenoid concentrations. Substantial declines in water-soluble carbohydrate concentrations were found in the shoots and roots under SM, particularly in Kangaroo Valley and PI231569, two relatively fast-growing genotypes. Significant increases in malondialdehyde concentrations were noted in the shoots and roots of all genotypes exposed to WL and SM, but to a greater extent in Kangaroo Valley and PI231569 under SM. Shoot activities of catalase (CAT) and peroxidase (POD) increased under SM, more pronounced in Silver Dollar and PI418714, two relatively slow-growing genotypes. Waterlogging or SM stresses decreased root activities of superoxide dismutase, CAT, POD and ascorbate peroxidase, especially for Kangaroo Valley and PI231569. The results indicated that maintenance of antioxidant activity and carbohydrate and minimization of lipid peroxidation could contribute to better waterlogging or submergence tolerance of perennial ryegrasses. PMID:26188499

  10. Induced systemic resistance responses in perennial ryegrass against Magnaporthe oryzae elicited by semi-purified surfactin lipopeptides and live cells of Bacillus amyloliquefaciens.

    PubMed

    Rahman, Alamgir; Uddin, Wakar; Wenner, Nancy G

    2015-08-01

    The suppressive ability of several strains of cyclic lipopeptide-producing Bacillus rhizobacteria to grey leaf spot disease caused by Magnaporthe oryzae has been documented previously; however, the underlying mechanism(s) involved in the induced systemic resistance (ISR) activity in perennial ryegrass (Lolium perenne L.) remains unknown. Root-drench application of solid-phase extraction (SPE)-enriched surfactin and live cells of mutant Bacillus amyloliquefaciens strain FZB42-AK3 (produces surfactin, but not bacillomycin D and fengycin) significantly reduced disease incidence and severity on perennial ryegrass. The application of the treatments revealed a pronounced multilayered ISR defence response activation via timely and enhanced accumulation of hydrogen peroxide (H2O2), elevated cell wall/apoplastic peroxidase activity, and deposition of callose and phenolic/polyphenolic compounds underneath the fungal appressoria in naïve leaves, which was significantly more intense in treated plants than in mock-treated controls. Moreover, a hypersensitive response (HR)-type reaction and enhanced expression of LpPrx (Prx, peroxidase), LpOXO4 (OXO, oxalate oxidase), LpPAL (PAL, phenylalanine ammonia lyase), LpLOXa (LOX, lipoxygenase), LpTHb (putative defensin) and LpDEFa (DEFa, putative defensin) in perennial ryegrass were associated with SPE-enriched surfactin and live AK3 cell treatments, acting as a second layer of defence when pre-invasive defence responses failed. The results indicate that ISR activity following surfactin perception may sensitize H2O2 -mediated defence responses, thereby providing perennial ryegrass with enhanced protection against M. oryzae. PMID:25285593

  11. Olivine Weathering in Soil, and Its Effects on Growth and Nutrient Uptake in Ryegrass (Lolium perenne L.): A Pot Experiment

    PubMed Central

    ten Berge, Hein F. M.; van der Meer, Hugo G.; Steenhuizen, Johan W.; Goedhart, Paul W.; Knops, Pol; Verhagen, Jan

    2012-01-01

    Mineral carbonation of basic silicate minerals regulates atmospheric CO2 on geological time scales by locking up carbon. Mining and spreading onto the earth's surface of fast-weathering silicates, such as olivine, has been proposed to speed up this natural CO2 sequestration (‘enhanced weathering’). While agriculture may offer an existing infrastructure, weathering rate and impacts on soil and plant are largely unknown. Our objectives were to assess weathering of olivine in soil, and its effects on plant growth and nutrient uptake. In a pot experiment with perennial ryegrass (Lolium perenne L.), weathering during 32 weeks was inferred from bioavailability of magnesium (Mg) in soil and plant. Olivine doses were equivalent to 1630 (OLIV1), 8150, 40700 and 204000 (OLIV4) kg ha−1. Alternatively, the soluble Mg salt kieserite was applied for reference. Olivine increased plant growth (+15.6%) and plant K concentration (+16.5%) in OLIV4. At all doses, olivine increased bioavailability of Mg and Ni in soil, as well as uptake of Mg, Si and Ni in plants. Olivine suppressed Ca uptake. Weathering estimated from a Mg balance was equivalent to 240 kg ha−1 (14.8% of dose, OLIV1) to 2240 kg ha−1 (1.1%, OLIV4). This corresponds to gross CO2 sequestration of 290 to 2690 kg ha−1 (29 103 to 269 103 kg km−2.) Alternatively, weathering estimated from similarity with kieserite treatments ranged from 13% to 58% for OLIV1. The Olsen model for olivine carbonation predicted 4.0% to 9.0% weathering for our case, independent of olivine dose. Our % values observed at high doses were smaller than this, suggesting negative feedbacks in soil. Yet, weathering appears fast enough to support the ‘enhanced weathering’ concept. In agriculture, olivine doses must remain within limits to avoid imbalances in plant nutrition, notably at low Ca availability; and to avoid Ni accumulation in soil and crop. PMID:22912685

  12. Association of simple sequence repeat (SSR) markers with submergence tolerance in diverse population of perennial ryegrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Submergence stress can cause the death of turfgrass plants. Identification of association between molecular markers and submergence tolerance-related traits facilitates an efficient selection of the tolerant cultivars for commercial production. A global collection of 99 diverse perennial ryegrass (L...

  13. Effects of the mycoparasite Sphaerellopsis filum on overwintering survival of stem rust in perennial ryegrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sphaerellopsis filum is a mycoparasite of Puccinia graminis subsp. graminicola (Pgg), a rust fungus that causes widespread crop damage on perennial ryegrass grown for seed. In observations taken over the winters of 2000-2003 S. filum was found in 10% of Pgg uredinia on 1st year plantings of perennia...

  14. Silicon induced systemic defense responses in perennial ryegrass against Magnaporthe oryzae infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sustainable integrated disease management for gray leaf spot of perennial ryegrass may involve use of plant defense elicitors with compatible traditional fungicides to reduce disease incidence and severity. Silicon (Si) is a potential inducer or modulator of plant defenses against different pathogen...

  15. Removal of nitrogen from wastewater with perennial ryegrass/artificial aquatic mats biofilm combined system.

    PubMed

    Chen, Chongjun; Zhang, Rui; Wang, Liang; Wu, Weixiang; Chen, Yingxu

    2013-04-01

    To develop a cost-effective combined phytoremediation and biological process, a combined perennial ryegrass/artificial aquatic mat biofilm reactor was used to treat synthetic wastewater. Influent ammonium loading, reflux ratio, hydraulic retention time (HRT) and temperature all had significant effects on the treatment efficiency. The results indicated that the effluent concentration of ammonium increased with increasing influent ammonium loading. The reactor temperature played an important role in the nitrification process. The ammonium removal efficiency significantly decreased from 80% to 30%-50% when the reactor temperature dropped to below 10 degrees C. In addition, the optimal nitrogen removal condition was a reflux ratio of 2. The nitrate and ammonium concentration of the effluent were consistent with the HRT of the combined system. The chemical oxygen demand (COD) removal efficiency was at a high level during the whole experiment, being almost 80% after the start-up, and then mostly above 90%. The direct uptake of N by the perennial ryegrass accounted for 18.17% of the total N removal by the whole system. The perennial ryegrass absorption was a significant contributor to nitrogen removal in the combined system. The result illustrated that the combined perennial ryegrass/artificial aquatic mat biofilm reactor demonstrated good performance in ammonium, total N and COD removal. PMID:23923775

  16. Identification of Candidate Reference Genes in Perennial Ryegrass for Quantitative RT-PCR under Various Abiotic Stress Conditions

    PubMed Central

    Jiang, Xiaomei; Yin, Guohua; Zhang, Xinquan; Qi, Xiao; Zhang, Yu; Yan, Yanhong; Ma, Xiao; Peng, Yan

    2014-01-01

    Background Quantitative real-time reverse-transcriptase PCR (qRT-PCR) is an important technique for analyzing differences in gene expression due to its sensitivity, accuracy and specificity. However, the stability of the expression of reference genes is necessary to ensure accurate qRT-PCR assessment of expression in genes of interest. Perennial ryegrass (Lolium perenne L.) is important forage and turf grass species in temperate regions, but the expression stability of its reference genes under various stresses has not been well-studied. Methodology/Principal Findings In this study, 11 candidate reference genes were evaluated for use as controls in qRT-PCR to quantify gene expression in perennial ryegrass under drought, high salinity, heat, waterlogging, and ABA (abscisic acid) treatments. Four approaches – Delta CT, geNorm, BestKeeper and Normfinder were used to determine the stability of expression in these reference genes. The results are consistent with the idea that the best reference genes depend on the stress treatment under investigation. Eukaryotic initiation factor 4 alpha (eIF4A), Transcription elongation factor 1 (TEF1) and Tat binding protein-1 (TBP-1) were the three most stably expressed genes under drought stress and were also the three best genes for studying salt stress. eIF4A, TBP-1, and Ubiquitin-conjugating enzyme (E2) were the most suitable reference genes to study heat stress, while eIF4A, TEF1, and E2 were the three best reference genes for studying the effects of ABA. Finally, Ubiquitin (UBQ), TEF1, and eIF4A were the three best reference genes for waterlogging treatments. Conclusions/Significance These results will be helpful in choosing the best reference genes for use in studies related to various abiotic stresses in perennial ryegrass. The stability of expression in these reference genes will enable better normalization and quantification of the transcript levels for studies of gene expression in such studies. PMID:24699822

  17. Detection of endophyte toxins in the imported perennial ryegrass straw.

    PubMed

    Miyazaki, S; Fukumura, M; Yoshioka, M; Yamanaka, N

    2001-09-01

    From 1997 to 1999, 29 cases of disorders were detected in cattle and horses that had been fed ryegrass straw imported from the U.S.A. These animals showed symptoms resembling ryegrass staggers and the clinical signs disappeared after removal of the straw. Endophytic hyphae were detected in the seeds of all straw samples that were responsible for the clinical cases. Lolitrem B concentrations in the straw ranged between 972 and 3740 ppb. Ergovaline concentrations were between 355 and 1300 ppb. Even though the concentrations of lolitrem B were lower than the toxic threshold proposed by Oregon State University in better part of the cases, our observations suggest the possibility that lolitrem B lower than the proposed threshold can bring disorders to sensitive individuals. PMID:11642270

  18. A mutualistic fungal symbiont of perennial ryegrass contains two different pyr4 genes, both expressing orotidine-5'-monophosphate decarboxylase.

    PubMed

    Collett, M A; Bradshaw, R E; Scott, D B

    1995-05-26

    A fragment of the Claviceps purpurea pyr4 gene, encoding orotidine-5'-monophosphate decarboxylase (OMP decarboxylase), was used to screen a genomic library from an isolate of a fungus, Acremonium sp. (designated Lp1), which grows as an endophyte in perennial ryegrass (Lolium perenne). Three positive clones, lambda MC11, lambda MC12 and lambda MC14, were isolated. Two of these clones, lambda MC12 and lambda MC14, were overlapping clones from the same locus, while lambda MC11 was from a different locus. Fragments of these clones which hybridised with C. purpurea pyr4 were sequenced and found to have similarity with pyr4 from other Pyrenomycete fungi. The pyr4 gene from lambda MC12 and lambda MC14 was designated pyr4-1 and that from lambda MC11 was designated pyr4-2. The predicted ORFs of the two genes were highly conserved, with 97.5% identity at the nucleotide level, the 5' non-coding sequences were the least conserved with 88.5% identity and the 3' non-coding sequences had 93.0% identity. RT-PCR analysis of total RNA from Lp1 demonstrated that transcripts from the two genes were present at similar levels, and hybridisation of pyr4-1 to Northern blots of total RNA from Lp1 showed that full-length transcripts were being produced. Genomic fragments containing pyr4 were transformed into a strain of Aspergillus nidulans which has a mutation in pyrG (encoding OMP decarboxylase). Both pyr4-1 and pyr4-2 complemented the pyrG mutation in A. nidulans, indicating that both encode functional OMP decarboxylases. It has been proposed [Schardl et al., Genetics 136 (1994) 1307-1317] that the two pyr4 in Lp1 arose by interspecific hybridisation, most likely between the ryegrass choke pathogen, Epichloë typhina, and another endophyte from perennial ryegrass, Acremonium lolii. Analysis by PCR amplification and direct sequencing of the variable 5' non-coding regions of pyr4, from possible ancestors to Lp1 supports this hypothesis. Comparisons of these sequences to the 5' non

  19. Pathotype-specific QTL for stem rust resistance in Lolium perenne

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A genetic map populated with RAD and SSR markers was created from F1 progeny of a stem rust-susceptible and stem rust-resistant parent of perennial ryegrass (Lolium perenne). The map has markers in common with several other Lolium spp. maps including EST-SSR anchor markers from a consensus map. A ...

  20. Silicon-Induced Systemic Defense Responses in Perennial Ryegrass Against Infection by Magnaporthe oryzae.

    PubMed

    Rahman, Alamgir; Wallis, Christopher M; Uddin, Wakar

    2015-06-01

    Sustainable integrated disease management for gray leaf spot of perennial ryegrass may involve use of plant defense elicitors with compatible traditional fungicides to reduce disease incidence and severity. Silicon (Si) has previously been identified as a potential inducer or modulator of plant defenses against different fungal pathogens. To this end, perennial ryegrass was inoculated with the causal agent of gray leaf spot, Magnaporthe oryzae, when grown in soil that was nonamended or amended with three different levels of calcium silicate (1, 5, or 10 metric tons [t]/ha). When applied at a rate of 5 t/ha, calcium silicate was found to significantly suppress gray leaf spot in perennial ryegrass, including a significant reduction of disease incidence (39.5%) and disease severity (47.3%). Additional studies observed nonpenetrated papillae or cell-wall appositions harboring callose, phenolic autofluorogens, and lignin-associated polyphenolic compounds in grass grown in the Si-amended soil. Regarding defense-associated enzyme levels, only following infection did grass grown in Si-amended soil exhibit greater activities of peroxidase and polyphenol oxidase than equivalent inoculated control plants. Also following infection with M. oryzae, grass levels of several phenolic acids, including chlorogenic acid and flavonoids, and relative expression levels of genes encoding phenylalanine ammonia lyase (PALa and PALb) and lipoxygenase (LOXa) significantly increased in Si-amended plants compared with that of nonamended control plants. These results suggest that Si-mediated increase of host defense responses to fungal pathogens in perennial ryegrass has a great potential to be part of an effective integrated disease management strategy against gray leaf spot development. PMID:25738553

  1. Using a Candidate Gene-Based Genetic Linkage Map to Identify QTL for Winter Survival in Perennial Ryegrass.

    PubMed

    Paina, Cristiana; Byrne, Stephen L; Studer, Bruno; Rognli, Odd Arne; Asp, Torben

    2016-01-01

    Important agronomical traits in perennial ryegrass (Lolium perenne) breeding programs such as winter survival and heading date, are quantitative traits that are generally controlled by multiple loci. Individually, these loci have relatively small effects. The aim of this study was to develop a candidate gene based Illumina GoldenGate 1,536-plex assay, containing single nucleotide polymorphism markers designed from transcripts involved in response to cold acclimation, vernalization, and induction of flowering. The assay was used to genotype a mapping population that we have also phenotyped for winter survival to complement the heading date trait previously mapped in this population. A positive correlation was observed between strong vernalization requirement and winter survival, and some QTL for winter survival and heading date overlapped on the genetic map. Candidate genes were located in clusters along the genetic map, some of which co-localized with QTL for winter survival and heading date. These clusters of candidate genes may be used in candidate gene based association studies to identify alleles associated with winter survival and heading date. PMID:27010567

  2. Using a Candidate Gene-Based Genetic Linkage Map to Identify QTL for Winter Survival in Perennial Ryegrass

    PubMed Central

    Paina, Cristiana; Byrne, Stephen L.; Studer, Bruno; Rognli, Odd Arne; Asp, Torben

    2016-01-01

    Important agronomical traits in perennial ryegrass (Lolium perenne) breeding programs such as winter survival and heading date, are quantitative traits that are generally controlled by multiple loci. Individually, these loci have relatively small effects. The aim of this study was to develop a candidate gene based Illumina GoldenGate 1,536-plex assay, containing single nucleotide polymorphism markers designed from transcripts involved in response to cold acclimation, vernalization, and induction of flowering. The assay was used to genotype a mapping population that we have also phenotyped for winter survival to complement the heading date trait previously mapped in this population. A positive correlation was observed between strong vernalization requirement and winter survival, and some QTL for winter survival and heading date overlapped on the genetic map. Candidate genes were located in clusters along the genetic map, some of which co-localized with QTL for winter survival and heading date. These clusters of candidate genes may be used in candidate gene based association studies to identify alleles associated with winter survival and heading date. PMID:27010567

  3. Overexpression of ubiquitin-like LpHUB1 gene confers drought tolerance in perennial ryegrass.

    PubMed

    Patel, Minesh; Milla-Lewis, Susana; Zhang, Wanjun; Templeton, Kerry; Reynolds, William C; Richardson, Kim; Biswas, Margaret; Zuleta, Maria C; Dewey, Ralph E; Qu, Rongda; Sathish, Puthigae

    2015-06-01

    HUB1, also known as Ubl5, is a member of the subfamily of ubiquitin-like post-translational modifiers. HUB1 exerts its role by conjugating with protein targets. The function of this protein has not been studied in plants. A HUB1 gene, LpHUB1, was identified from serial analysis of gene expression data and cloned from perennial ryegrass. The expression of this gene was reported previously to be elevated in pastures during the summer and by drought stress in climate-controlled growth chambers. Here, pasture-type and turf-type transgenic perennial ryegrass plants overexpressing LpHUB1 showed improved drought tolerance, as evidenced by improved turf quality, maintenance of turgor and increased growth. Additional analyses revealed that the transgenic plants generally displayed higher relative water content, leaf water potential, and chlorophyll content and increased photosynthetic rate when subjected to drought stress. These results suggest HUB1 may play an important role in the tolerance of perennial ryegrass to abiotic stresses. PMID:25487628

  4. Origin of a Fungal Symbiont of Perennial Ryegrass by Interspecific Hybridization of a Mutualist with the Ryegrass Choke Pathogen, Epichloe Typhina

    PubMed Central

    Schardl, C. L.; Leuchtmann, A.; Tsai, H. F.; Collett, M. A.; Watt, D. M.; Scott, D. B.

    1994-01-01

    Seed-borne fungal symbionts (endophytes) provide many cool-season grass species with biological protection from biotic and abiotic stresses. The endophytes are asexual, whereas closely related sexual species of genus Epichloe (Clavicipitales) cause grass choke disease. Perennial ryegrass (Lolium perenne) is a host of two endophyte taxa, LpTG-1 (L. perenne endophyte taxonomic grouping one = Acremonium lolii) and LpTG-2, as well as the choke pathogen, Epichloe typhina (represented by isolate E8). Relationships among these fungi and other Epichloe species were investigated by analysis of gene sequences, DNA polymorphisms and allozymes. The results indicate that LpTG-2 is a heteroploid derived from an interspecific hybrid. The LpTG-2 isolates had two copies each of nine out of ten genes analyzed (the exception being the rRNA gene locus), and the profiles for seven of these were composites of those from E. typhina E8 and A. lolii isolate Lp5. Molecular phylogenetic analysis grouped the two β-tubulin genes of LpTG-2 into separate clades. One (tub2-1) was related to that of E. typhina E8, and the other (tub2-2) to that of A. lolii. The mitochondrial DNA profile of LpTG-2 was similar to that of A. lolii, but its rRNA gene sequence grouped it with E. typhina E8. A proposed model for the evolution of LpTG-2 involves infection of a L. perenne-A. lolii symbiotum by E. typhina, followed by hybridization of the two fungi. Such interspecific hybridization may be a common and important mechanism for genetic variation in Epichloe endophytes. PMID:8013907

  5. Self-Reseeding Potential and Herbage Production of Italian Ryegrass (Lolium Multiflorum Lam.) Affected by Date and Intensity of Initial Harvest

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Annually-sown cool-season small grain cereals can provide a valuable source of cool-season feeding for livestock in the southern Great Plains of the USA, but for many farmers limited access to field equipment for cultivation and planting is an obstacle to their use. Italian ryegrass (Lolium multiflo...

  6. [Effects of ryegrass (Lolium perenne) root exudates dose on pyrene degradation and soil microbes in pyrene-contaminated soil].

    PubMed

    Xie, Xiao-mei; Liao, Min; Yang, Jing

    2011-10-01

    By simulating a gradually decreasing concentration of root exudates with the distance away from root surface in rhizosphere, this paper studied the effects of ryegrass (Lolium perenne) root exudates dose on the pyrene degradation and microbial ecological characteristics in a pyrene-contaminated soil. It was observed that with the increasing dose of ryegrass root exudates, the residual amount of soil pyrene changed nonlinearly, i. e. , increased after an initial decrease. When the root exudates dose was 32.75 mg kg(-1) of total organic carbon, the residual pyrene was the minimum, indicating that the root exudates at this dose stimulated pyrene degradation significantly. In the meantime, soil microbial biomass carbon and microbial quotient had an opposite trend, suggesting the close relationship between pyrene degradation and soil microbes. In the test soil, microbial community was dominated by bacteria, and the bacteria had the same variation trend as the pyrene degradation, which indicated that the pyrene was degraded mainly by bacteria, and the effects of root exudates on pyrene degradation were mainly carried out through the effects on bacterial population. There was a similar variation trend between the activity of soil dehydrogenase, a microbial endoenzyme catalyzing the dehydrogenation of organic matter, and the soil microbes, which further demonstrated that the variations of soil microbes and their biochemical characteristics were the ecological mechanisms affecting the pyrene degradation in the pyrene-contaminated soil when the ryegrass root exudates dose increased. PMID:22263480

  7. Linkage Disequilibrium Among Two Lolium Perenne CBF Genes and Association With Freezing Susceptibility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Perennial ryegrass(Lolium perenne) is one of the most abundantly utilized forage and turfgrass species; however, its lack of tolerance to freezing temperatures relative to other forage/turf grasses limits its use. A pseudo-testcross genetic mapping population was previously developed for perennial ...

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

    PubMed Central

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

    2010-01-01

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

  9. Comparative Analysis of Multiple Disease Resistance in Ryegrass and Cereal Crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Perennial ryegrass (Lolium perenne) is one of the most important forage crops in Europe and Australia and also a popular turfgrass in North America. Improvement of resistance to multiple diseases is desirable for such a perennial crop which has long rotation cycles. Quantitative trait loci (QTL) an...

  10. Overexpression of a Chimeric Gene, OsDST-SRDX, Improved Salt Tolerance of Perennial Ryegrass

    PubMed Central

    Cen, Huifang; Ye, Wenxing; Liu, Yanrong; Li, Dayong; Wang, Kexin; Zhang, Wanjun

    2016-01-01

    The Drought and Salt Tolerance gene (DST) encodes a C2H2 zinc finger transcription factor, which negatively regulates salt tolerance in rice (Oryza sativa). Phylogenetic analysis of six homologues of DST genes in different plant species revealed that DST genes were conserved evolutionarily. Here, the rice DST gene was linked to an SRDX domain for gene expression repression based on the Chimeric REpressor gene-Silencing Technology (CRES-T) to make a chimeric gene (OsDST-SRDX) construct and introduced into perennial ryegrass by Agrobacterium-mediated transformation. Integration and expression of the OsDST-SRDX in transgenic plants were tested by PCR and RT-PCR, respectively. Transgenic lines overexpressing the OsDST-SRDX fusion gene showed obvious phenotypic differences and clear resistance to salt-shock and to continuous salt stresses compared to non-transgenic plants. Physiological analyses including relative leaf water content, electrolyte leakage, proline content, malondialdehyde (MDA) content, H2O2 content and sodium and potassium accumulation indicated that the OsDST-SRDX fusion gene enhanced salt tolerance in transgenic perennial ryegrass by altering a wide range of physiological responses. To our best knowledge this study is the first report of utilizing Chimeric Repressor gene-Silencing Technology (CRES-T) in turfgrass and forage species for salt-tolerance improvement. PMID:27251327

  11. Overexpression of a Chimeric Gene, OsDST-SRDX, Improved Salt Tolerance of Perennial Ryegrass.

    PubMed

    Cen, Huifang; Ye, Wenxing; Liu, Yanrong; Li, Dayong; Wang, Kexin; Zhang, Wanjun

    2016-01-01

    The Drought and Salt Tolerance gene (DST) encodes a C2H2 zinc finger transcription factor, which negatively regulates salt tolerance in rice (Oryza sativa). Phylogenetic analysis of six homologues of DST genes in different plant species revealed that DST genes were conserved evolutionarily. Here, the rice DST gene was linked to an SRDX domain for gene expression repression based on the Chimeric REpressor gene-Silencing Technology (CRES-T) to make a chimeric gene (OsDST-SRDX) construct and introduced into perennial ryegrass by Agrobacterium-mediated transformation. Integration and expression of the OsDST-SRDX in transgenic plants were tested by PCR and RT-PCR, respectively. Transgenic lines overexpressing the OsDST-SRDX fusion gene showed obvious phenotypic differences and clear resistance to salt-shock and to continuous salt stresses compared to non-transgenic plants. Physiological analyses including relative leaf water content, electrolyte leakage, proline content, malondialdehyde (MDA) content, H2O2 content and sodium and potassium accumulation indicated that the OsDST-SRDX fusion gene enhanced salt tolerance in transgenic perennial ryegrass by altering a wide range of physiological responses. To our best knowledge this study is the first report of utilizing Chimeric Repressor gene-Silencing Technology (CRES-T) in turfgrass and forage species for salt-tolerance improvement. PMID:27251327

  12. Use of Spinach, Radish, and Perennial Ryegrass to Assess the Availability of Metals in Waste Foundry Sands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant uptake is a major pathway by which potentially toxic metals can enter the food chain. In this laboratory study we grew spinach, radish, and perennial ryegrass in sand blends containing 50% waste foundry sand (WFS) to assess the availability of Al, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn,...

  13. A sensitive PCR-based assay to detect Neotyphodium fungi in seed and plant tissue of tall fescue and ryegrass spp.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A polymerase chain reaction (PCR)-based method for detection of Neotyphodium endophytes in seed and plant tissue from tall fescue (Festuca arundinacea Schreb.), Italian (Lolium multiflorum Lam.) and perennial (Lolium perenne L.) ryegrasses was developed. Based on DNA mixture tests and bulk seed anal...

  14. Investigating the Mechanism of Glyphosate Resistance in Rigid Ryegrass (Lolium rigidum)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Glyphosate is a broad-spectrum herbicide that has been used extensively for more than 20 yr. The first glyphosate-resistant weed biotype appeared in 1996; it involved a rigid ryegrass population from Australia that exhibited an LD50 value approximately 10-fold higher than that of sensitive biotypes....

  15. Differential Response to Glyphosate in Italian Ryegrass (Lolium multiflorum) Populations from Mississippi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two Italian ryegrass populations from Mississippi, Tribbett and Fratesi, were suspected to be tolerant to glyphosate. A third population from Mississippi, Elizabeth, known to be susceptible to glyphosate, was included for comparison. Plants, 10- to 15-cm-tall (3 to 6 leaves, 2 to 3 tillers), were tr...

  16. Glyphosate-tolerance mechanism in Italian ryegrass (Lolium multiflorum) from Mississippi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A 3-fold glyphosate tolerance was identified in two Italian ryegrass populations, T1 and T2, from Mississippi. Laboratory experiments were conducted to characterize the mechanism of glyphosate tolerance in these populations. The T1 population absorbed less 14C-glyphosate (43% of applied) compared to...

  17. Enhancement of nitrogen and phosphorus removal from eutrophic water by economic plant annual ryegrass (Lolium multiflorum) with ion implantation.

    PubMed

    Li, Miao; Sheng, Guo-ping; Wu, Yue-jin; Yu, Zeng-liang; Bañuelos, Gary S; Yu, Han-qing

    2014-01-01

    Severe eutrophication of surface water has been a major problem of increasing environmental concern worldwide. In the present study, economic plant annual ryegrass (Lolium multiflorum) was grown in floating mats as an economic plant-based treatment system to evaluate its potential after ion implantation for removing nutrients in simulated eutrophic water. The specific weight growth rate of L. multiflorum with ion implantation was significantly greater than that of the control, and the peroxidase, nitrate reductase, and acid phosphatase activities of the irradiated L. multiflorum were found to be greater than those plants without ion implantation. Higher total nitrogen (TN) and total phosphorus (TP) removal efficiencies were obtained for the L. multiflorum irradiated with 25 keV 5.2 × 10(16) N(+) ions/cm(2) and 30 keV 4.16 × 10(16) N(+) ions/cm(2), respectively (p < 0.05). Furthermore, the nitrogen and phosphorus contents in the plant biomass with ion implantation were also greater than those in the control and were positively correlated with TN and TP supplied. L. multiflorum itself was directly responsible for 39-49 and 47-58 % of the overall N and P removal in the experiment, respectively. The research results suggested that ion implantation could become a promising approach for increasing phytoremediation efficiency of nutrients from eutrophic water by L. multiflorum. PMID:24809498

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

    PubMed Central

    2010-01-01

    Background Genetic markers and linkage mapping are basic prerequisites for marker-assisted selection and map-based cloning. In the case of the key grassland species Lolium spp., numerous mapping populations have been developed and characterised for various traits. Although some genetic linkage maps of these populations have been aligned with each other using publicly available DNA markers, the number of common markers among genetic maps is still low, limiting the ability to compare candidate gene and QTL locations across germplasm. Results A set of 204 expressed sequence tag (EST)-derived simple sequence repeat (SSR) markers has been assigned to map positions using eight different ryegrass mapping populations. Marker properties of a subset of 64 EST-SSRs were assessed in six to eight individuals of each mapping population and revealed 83% of the markers to be polymorphic in at least one population and an average number of alleles of 4.88. EST-SSR markers polymorphic in multiple populations served as anchor markers and allowed the construction of the first comprehensive consensus map for ryegrass. The integrated map was complemented with 97 SSRs from previously published linkage maps and finally contained 284 EST-derived and genomic SSR markers. The total map length was 742 centiMorgan (cM), ranging for individual chromosomes from 70 cM of linkage group (LG) 6 to 171 cM of LG 2. Conclusions The consensus linkage map for ryegrass based on eight mapping populations and constructed using a large set of publicly available Lolium EST-SSRs mapped for the first time together with previously mapped SSR markers will allow for consolidating existing mapping and QTL information in ryegrass. Map and markers presented here will prove to be an asset in the development for both molecular breeding of ryegrass as well as comparative genetics and genomics within grass species. PMID:20712870

  19. Vacuolar glyphosate-sequestration correlates with glyphosate resistance in ryegrass (Lolium spp.) from Australia, South America, and Europe: a 31P NMR investigation.

    PubMed

    Ge, Xia; d'Avignon, D André; Ackerman, Joseph J H; Collavo, Alberto; Sattin, Maurizio; Ostrander, Elizabeth L; Hall, Erin L; Sammons, R Douglas; Preston, Christopher

    2012-02-01

    Lolium spp., ryegrass, variants from Australia, Brazil, Chile, and Italy showing differing levels of glyphosate resistance were examined by (31)P NMR. Extents of glyphosate (i) resistance (LD(50)), (ii) inhibition of 5-enopyruvyl-shikimate-3-phosphate synthase (EPSPS) activity (IC(50)), and (iii) translocation were quantified for glyphosate-resistant (GR) and glyphosate-sensitive (GS) Lolium multiflorum Lam. variants from Chile and Brazil. For comparison, LD(50) and IC(50) data for Lolium rigidum Gaudin variants from Italy were also analyzed. All variants showed similar cellular uptake of glyphosate by (31)P NMR. All GR variants showed glyphosate sequestration within the cell vacuole, whereas there was minimal or no vacuole sequestration in the GS variants. The extent of vacuole sequestration correlated qualitatively with the level of resistance. Previous (31)P NMR studies of horseweed ( Conyza canadensis (L.) Cronquist) revealed that glyphosate sequestration imparted glyphosate resistance. Data presented herein suggest that glyphosate vacuolar sequestration is strongly contributing, if not the major contributing, resistance mechanism in ryegrass as well. PMID:22224711

  20. Fluxes of Reserve-Derived and Currently Assimilated Carbon and Nitrogen in Perennial Ryegrass Recovering from Defoliation. The Regrowing Tiller and Its Component Functionally Distinct Zones1

    PubMed Central

    Schnyder, Hans; de Visser, Ries

    1999-01-01

    The quantitative significance of reserves and current assimilates in regrowing tillers of severely defoliated plants of perennial ryegrass (Lolium perenne L.) was assessed by a new approach, comprising 13C/12C and 15N/14N steady-state labeling and separation of sink and source zones. The functionally distinct zones showed large differences in the kinetics of currently assimilated C and N. These are interpreted in terms of ”substrate” and ”tissue” flux among zones and C and N turnover within zones. Tillers refoliated rapidly, although C and N supply was initially decreased. Rapid refoliation was associated with (a) transient depletion of water-soluble carbohydrates and dilution of structural biomass in the immature zone of expanding leaves, (b) rapid transition to current assimilation-derived growth, and (c) rapid reestablishment of a balanced C:N ratio in growth substrate. This balance (C:N, approximately 8.9 [w/w] in new biomass) indicated coregulation of growth by C and N supply and resulted from complementary fluxes of reserve- and current assimilation-derived C and N. Reserves were the dominant N source until approximately 3 d after defoliation. Amino-C constituted approximately 60% of the net influx of reserve C during the first 2 d. Carbohydrate reserves were an insignificant source of C for tiller growth after d 1. We discuss the physiological mechanisms contributing to defoliation tolerance. PMID:10198102

  1. Pollen Expression of Herbicide Target Site Resistance Genes in Annual Ryegrass (Lolium rigidum).

    PubMed Central

    Richter, J.; Powles, S. B.

    1993-01-01

    Herbicide resistance can occur either through target-site insensitivity or by nontarget site-based mechanisms. Two herbicide-resistant biotypes of Lolium rigidum Gaud., one resistant to acetolactate synthase (ALS)-inhibiting herbicides (biotype WLR1) and the other resistant to acetyl CoA carboxylase (ACCase)-inhibiting herbicides (biotype WLR96) through target-site insensitivity at the whole plant and enzymic levels, were found to express this resistance in the pollen. Pollen produced by resistant biotypes grew uninhibited when challenged with herbicide, whereas that from a susceptible biotype was inhibited. A third biotype, SLR31, resistant to ACCase-inhibiting and certain ALS-inhibiting herbicides at the whole plant level through nontarget site-based mechanisms, did not exhibit this expression in the pollen. The technique described may form the basis for a rapid screen for certain nuclear-encoded, target site-based herbicide-resistance mechanisms. PMID:12231886

  2. Evaluation of reference genes for quantitative RT-PCR in Lolium perenne

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Quantitative real-time RT-PCR provides an important tool for analyzing gene expression if proper internal standards are used. The aim of this study was to identify and evaluate reference genes for use in real-time quantitative RT-PCR in perennial ryegrass (Lolium perenne L.) during plant developmen...

  3. Genotype _ environment interactions for forage yield of Lolium perenne L. sward plots in Ireland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lolium perenne L. (perennial ryegrass) is by far the most widely sown grass species in Ireland. Genotype by environment (G by E) interactions are a frequent occurrence in forage yield evaluations. The objectives were to determine (i) the nature and relative magnitudes of the pertinent G by E interac...

  4. Mineral accumulation by perennial grasses in a high rainfall environment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Straw produced as a co-product of perennial ryegrass (Lolium perenne L.), orchardgrass (Dactylis glomerata), tall fescue (Schedonorus phoenix (Scop.) Holub), and Kentucky bluegrass (Poa pratensis L.) seed production in the high rainfall area of western Oregon as well as clippings from urban and recr...

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

    SciTech Connect

    Evans, Barbara R; Bali, Garima; Reeves, David T; O'Neill, Hugh Michael; Sun, Qining; Shah, Riddhi S; Ragauskas, Arthur

    2014-01-01

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

  6. Genetic diversity analysis in Tunisian perennial ryegrass germplasm as estimated by RAPD, ISSR, and morpho-agronomical markers.

    PubMed

    Ghariani, S; Elazreg, H; Chtourou-Ghorbel, N; Chakroun, M; Trifi-Farah, N

    2015-01-01

    Tunisia is rich in diverse forage and pasture species including perennial ryegrass. In order to enhance forage production and improve agronomic performance of this local germplasm, a molecular analysis was undertaken. Random amplified polymorphic DNA (RAPD), inter simple sequence repeats (ISSR) and morpho-agronomical traits markers were used for genetic diversity estimation of ryegrass germplasm after screening 20 spontaneous accessions, including a local and an introduced cultivars. Same mean polymorphism information content values were obtained (0.37) for RAPD and ISSR suggesting that both marker systems were equally effective in determining polymorphisms. The average pairwise genetic distance values were 0.57 (morpho-agronomical traits), 0.68 (RAPD), and 0.51 (ISSR) markers data sets. A higher Shannon diversity index was obtained with ISSR marker (0.57) than for RAPD (0.54) and morpho-agronomical traits (0.36). The Mantel test based on genetic distances of a combination of molecular markers and morpho-agronomical data exhibited a significant correlation between RAPD and ISSR data, suggesting that the use of a combination of molecular techniques was a highly efficient method of estimating genetic variability levels among Tunisian ryegrass germplasm. In summary, results showed that combining molecular and morpho-agronomical markers is an efficient way in assessing the genetic variability among Tunisian ryegrass genotypes. In addition, the combined analysis provided an exhaustive coverage for the analyzed diversity and helped us to identify suitable accessions showed by Beja and Jendouba localities, which present large similarities with cultivated forms and can be exploited for designing breeding programmes, conservation of germplasm and management of ryegrass genetic resources. PMID:26782500

  7. EFFICIENCY OF INDIRECT SELECTION FOR DRY MATTER YIELD BASED ON FRESH MATTER YIELD IN LOLIUM PERENNE L. SWARD PLOTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forage dry matter yield (DMY) is a high-priority trait in breeding perennial ryegrass (Lolium perenne L.). However, determining dry matter concentration is highly labor intensive. Indirect selection based on fresh matter yield (FMY) would be easier, quicker and less expensive and, for a similar leve...

  8. Milk production and composition of mid-lactation cows consuming perennial ryegrass-and chicory-based diets.

    PubMed

    Muir, S K; Ward, G N; Jacobs, J L

    2014-02-01

    Dry matter intakes (DMI), nutrient selection, and milk production responses of dairy cows grazing 3 herbage-based diets offered at 2 allowances were measured. The 2 allowances were 20 (low) and 30 (high) kg of dry matter (DM)/cow per day and these were applied to 3 herbage types: perennial ryegrass (PRG) and chicory (CHIC+) monocultures and a mixed sward of chicory and perennial ryegrass (MIX). The CHIC+ diet was supplemented with alfalfa hay (approximately 2 kg of DM/cow per day) to maintain dietary neutral detergent fiber (NDF) concentration and all diets were supplemented with energy-based pellets (6 kg of DM/cow per day). Holstein-Friesian dairy cows averaging 136 ± 30 d in milk were allocated to 4 replicates of the 6 treatments using stratified randomization procedures. Cows were adapted to their experimental diets over a 14-d period, with measurements of DMI, milk yield, and composition conducted over the following 10 d. Herbage DMI was lowest (12.8 vs. 14.0 kg of DM/d) for CHIC+ compared with the MIX and PRG, although total forage intake (grazed herbage plus hay) was similar (14.0 to 15.0 kg of DM/d) across the 3 treatments. Milk production, milk protein, and milk fat concentrations were not different between herbage types. Grazed herbage DMI increased with increasing herbage allowance and this was associated with increased milk protein concentration (3.23 to 3.34%) and total casein production (41.7 to 43.6 mg/g). Concentrations of polyunsaturated fatty acids in milk fat, particularly linoleic acid, were increased in milk from cows offered the CHIC+ or the MIX diets, indicating potential benefits of chicory herbage on milk fatty acid concentrations. Although feeding CHIC+ or MIX did not increase milk yield, these herbage types could be used as an alternative to perennial ryegrass pasture in spring. PMID:24290818

  9. Allelic Variation in the Perennial Ryegrass FLOWERING LOCUS T Gene Is Associated with Changes in Flowering Time across a Range of Populations1[W

    PubMed Central

    Skøt, Leif; Sanderson, Ruth; Thomas, Ann; Skøt, Kirsten; Thorogood, Danny; Latypova, Galina; Asp, Torben; Armstead, Ian

    2011-01-01

    The Arabidopsis (Arabidopsis thaliana) FLOWERING LOCUS T (FT) gene and its orthologs in other plant species (e.g. rice [Oryza sativa] OsFTL2/Hd3a) have an established role in the photoperiodic induction of flowering response. The genomic and phenotypic variations associated with the perennial ryegrass (Lolium perenne) ortholog of FT, designated LpFT3, was assessed in a diverse collection of nine European germplasm populations, which together constituted an association panel of 864 plants. Sequencing and genotyping of a series of amplicons derived from the nine populations, containing the complete exon and intron sequences as well as 5′ and 3′ noncoding sequences of LpFT3, identified a total of seven haplotypes. Genotyping assays designed to detect the genomic variation showed that three haplotypes were present in approximately equal proportions and represented 84% of the total, with a fourth representing a further 11%. Of the three major haplotypes, two were predicted to code for identical protein products and the third contained two amino acid substitutions. Association analysis using either a mixed model with a relationship matrix to correct for population structure and relatedness or structured association with further correction using genomic control indicated significant associations between LpFT3 and variation in flowering time. These associations were corroborated in a validation population segregating for the same major alleles. The most “diagnostic” region of genomic variation was situated 5′ of the coding sequence. Analysis of this region identified that the interhaplotype variation was closely associated with sequence motifs that were apparently conserved in the 5′ region of orthologs of LpFT3 from other plant species. These may represent cis-regulatory elements involved in influencing the expression of this gene. PMID:21115808

  10. Is the vertical transmission of Neotyphodium lolii in perennial ryegrass the only possible way to the spread of endophytes?

    PubMed

    Wiewióra, Barbara; Żurek, Grzegorz; Pańka, Dariusz

    2015-01-01

    Endophytic fungi live their whole life within host tissues usually without any visible symptoms. Their vertical transmission (seed-plant-seed) has been well described and documented. However, horizontal transmission (plant-plant) needs more clarification. The aim of this study was to assess the extent to which endophytes move vertically in ecotypes of perennial ryegrass and whether there is evidence for the horizontal transmission of endophytes. Ecotypes from grasslands in Poland were collected in the form of living plants and used for vertical transmission analysis. Plants, the seed collected from these plants and plants grown from this collected seed were tested for endophytic infection. Provided that all produced seeds were viable and able to germinate and produce seedlings, the vertical transmission of Neotyphodium endophytes in perennial ryegrass ecotypes was nearly complete. For the horizontal transmission experiment, endophyte-hosting plants (E+) and endophyte-free plants (E-) of four cultivars were planted in the field in close proximity on small plots that were frequently mown. These studies revealed that after 7 months of growth next to E+ plants, the characteristic Neotyphodium spp. mycelia were found in E- plants, which was especially true for plants growing in close proximity to the infected plants. The occurrence of horizontal transmission of endophytes has not been previously demonstrated. PMID:25680199

  11. Is the Vertical Transmission of Neotyphodium lolii in Perennial Ryegrass the Only Possible Way to the Spread of Endophytes?

    PubMed Central

    Wiewióra, Barbara; Żurek, Grzegorz; Pańka, Dariusz

    2015-01-01

    Endophytic fungi live their whole life within host tissues usually without any visible symptoms. Their vertical transmission (seed-plant-seed) has been well described and documented. However, horizontal transmission (plant-plant) needs more clarification. The aim of this study was to assess the extent to which endophytes move vertically in ecotypes of perennial ryegrass and whether there is evidence for the horizontal transmission of endophytes. Ecotypes from grasslands in Poland were collected in the form of living plants and used for vertical transmission analysis. Plants, the seed collected from these plants and plants grown from this collected seed were tested for endophytic infection. Provided that all produced seeds were viable and able to germinate and produce seedlings, the vertical transmission of Neotyphodium endophytes in perennial ryegrass ecotypes was nearly complete. For the horizontal transmission experiment, endophyte-hosting plants (E+) and endophyte-free plants (E-) of four cultivars were planted in the field in close proximity on small plots that were frequently mown. These studies revealed that after 7 months of growth next to E+ plants, the characteristic Neotyphodium spp. mycelia were found in E- plants, which was especially true for plants growing in close proximity to the infected plants. The occurrence of horizontal transmission of endophytes has not been previously demonstrated. PMID:25680199

  12. Field assessment of a model for fungicide effects on within-plant spread of stem rust in perennial ryegrass seed crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Within-plant spread of stem rust (Puccinia graminis subsp. graminicola) in perennial ryegrass during tiller extension is a major determinant of epidemic severity and is dominated by stem extension dynamics. Simple equations for extension of inflorescence and internodes are presented and parameteriz...

  13. Tilletia vankyi, a new species of reticulate-spored bunt fungus with non-conjugating basidiospores infecting species of Festuca and Lolium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A bunt fungus infecting commercial perennial ryegrass (Lolium perenne) from Australia and chewings fescue (Festuca rubra) from the U.S.A. exhibits a spore germination pattern that is unique from other reticulately-spored species of Tilletia infecting hosts in the grass subfamily Pooideae. Teliospor...

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

  15. Bioaccumulation of metals in ryegrass (Lolium perenne L.) following the application of lime stabilised, thermally dried and anaerobically digested sewage sludge.

    PubMed

    Healy, M G; Ryan, P C; Fenton, O; Peyton, D P; Wall, D P; Morrison, L

    2016-08-01

    The uptake and accumulation of metals in plants is a potential pathway for the transfer of environmental contaminants in the food chain, and poses potential health and environmental risks. In light of increased population growth and urbanisation, the safe disposal of sewage sludge, which can contain significant levels of toxic contaminants, remains an environmental challenge globally. The aims of this experiment were to apply municipal sludge, having undergone treatment by thermal drying, anaerobic digestion, and lime stabilisation, to permanent grassland in order to assess the bioaccumulation of metals (B, Al, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, As, Nb, Mo, Sb, Ba, W, Pb, Fe, Cd) by perennial ryegrass over a period of up to 18 weeks after application. The legislation currently prohibits use of grassland for fodder or grazing for at least three weeks after application of treated sewage sludge (biosolids). Five treatments were used: thermally dried (TD), anaerobically digested (AD) and lime stabilised (LS) sludge all from one wastewater treatment plant (WWTP), AD sludge from another WWTP, and a study control (grassland only, without application of biosolids). In general, there was no significant difference in metal content of the ryegrass between micro-plots that received treated municipal sludge and the control over the study duration. The metal content of the ryegrass was below the levels at which phytotoxicity occurs and below the maximum levels specified for animal feeds. PMID:27174047

  16. Fructans, But Not the Sucrosyl-Galactosides, Raffinose and Loliose, Are Affected by Drought Stress in Perennial Ryegrass

    PubMed Central

    Amiard, Véronique; Morvan-Bertrand, Annette; Billard, Jean-Pierre; Huault, Claude; Keller, Felix; Prud'homme, Marie-Pascale

    2003-01-01

    The aim of this study was to evaluate the putative role of the sucrosyl-galactosides, loliose [α-d-Gal (1,3) α-d-Glc (1,2) β-d-Fru] and raffinose [α-d-Gal (1,6) α-d-Glc (1,2) β-d-Fru], in drought tolerance of perennial ryegrass and to compare it with that of fructans. To that end, the loliose biosynthetic pathway was first established and shown to operate by a UDP-Gal: sucrose (Suc) 3-galactosyltransferase, tentatively termed loliose synthase. Drought stress increased neither the concentrations of loliose and raffinose nor the activities of loliose synthase and raffinose synthase (EC 2.4.1.82). Moreover, the concentrations of the raffinose precursors, myoinositol and galactinol, as well as the gene expressions of myoinositol 1-phosphate synthase (EC 5.5.1.4) and galactinol synthase (EC 2.4.1.123) were either decreased or unaffected by drought stress. Taken together, these data are not in favor of an obvious role of sucrosyl-galactosides in drought tolerance of perennial ryegrass at the vegetative stage. By contrast, drought stress caused fructans to accumulate in leaf tissues, mainly in leaf sheaths and elongating leaf bases. This increase was mainly due to the accumulation of long-chain fructans (degree of polymerization > 8) and was not accompanied by a Suc increase. Interestingly, Suc but not fructan concentrations greatly increased in drought-stressed roots. Putative roles of fructans and sucrosyl-galactosides are discussed in relation to the acquisition of stress tolerance. PMID:12913176

  17. ESPS gene amplification endows resistance to glyphosate in Italian ryegrass (Lolium perene ssp multiflorum) from Arkansas, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Resistance to glyphosate in weed species is a major challenge for the sustainability of glyphosate use in crop and non-crop systems, and especially in glyphosate-resistant crops. A glyphosate-resistant Italian ryegrass population has been identified in Arkansas. This research was conducted to elucid...

  18. Seed size effects on early seedling growth and response to applied nitrogen in annual ryegrass (Lolium multiflorum L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Use of individual plants as experimental units may be necessary when resources are limited, but inter-plant variation risks obscuring differences among treatments. Experiments were undertaken to measure the effects of seed size on seedling size and response to applied nitrogen of annual ryegrass (Lo...

  19. EPSPS gene amplification in glyphosate-resistant in Italian ryegrass (Lolium perenne ssp. multiflorum) populations from Arkansas, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Glyphosate-resistant Italian ryegrass was detected in Arkansas, USA in 2007. In 2014, 45 populations were confirmed resistant in eight counties across the state. The level of resistance and resistance mechanisms in six populations was studied to assess the severity of the problem and identify altern...

  20. Germination and Seedling Growth of Perennial Ryegrass in Acid Sulfate Soil Treated by Pyrite Nano-Encapsulation

    NASA Astrophysics Data System (ADS)

    Lee, J.; Kim, J.; Yi, J.; Kim, T.

    2007-05-01

    The trial pot experiment was conducted to validate the effect of encapsulation in reduction of acid rock drainage. Six different treatments were performed: A = control, four times spraying of distilled water; B = four times of 0.01 M H2O2; C = once-encapsulated and three times spraying of distilled water; D = twice-encapsulated and twice spraying of distilled water; E = three times-encapsulated and once spraying of distilled water and F = four times-encapsulated for the acid sulfate soil with pyrite bearing andesite powder and sand. After the encapsulation treatment, the perennial ryegrass (Loium perenne) was sowed to evaluate germination rate and growth for three months. The leachate was examined for the chemical properties. The leachate from the A pot (control) is characterized as acidic (pH below 3) and high concentrations of SO4-2: 12,022 mg/L, Al: 85.8 mg/L and Mn: 34.1 mg/L which can be toxic effect to the plant growth. However, the leachate from encapsulated pots showed near neutral (pH 6 to 7) and low concentrations of SO4-2 (below 3,000 mg/L), Al (below 45mg/L) and Mn (24 gm/L). The frequency of encapsulation treatment is related to reduction of acidic drainage. It was hard to identify the significant difference of the seed germination rate of ryegrass between the treatments, although root and shoot growth showed three times difference between the control (1.90g/pot) and four times encapsulated treatment (6.33g/pot) after 2 month growth. It is suggested that encapsulation of pyrite in acid sulfate soil causes the reduction of acidic drainage resulting in the higher growth of herbaceous plants.

  1. Effects of olive mill wastewater physico-chemical treatments on polyphenol abatement and Italian ryegrass (Lolium multiflorum Lam.) germinability.

    PubMed

    Barbera, A C; Maucieri, C; Ioppolo, A; Milani, M; Cavallaro, V

    2014-04-01

    Direct spreading on agricultural lands may represent an environmentally friendly disposal method and a possible use of water and nutrients from olive mill wastewaters (OMWs). However, the agronomic use of OMWs is limited, among others by polyphenols, which exert phytotoxic effects. Activated charcoal (AC) has been recognized as a very effective agent for polyphenol abatement, as it enables an irreversible process of phenol adsorption. Addition of calcium hydroxide (Ca(OH)2) has also been described as a cheap and effective method in polyphenols abatement. However, the effects of Ca(OH)2 addition to OMW on seed germination are unclear. In this paper, the effects of AC and/or Ca(OH)2 on OMW polyphenols abatement, and Lolium multiflorum seed germination have been investigated. The highest polyphenols removal, approximately 95%, was observed when 80 g L(-1) of AC was added to OMWs (the maximum dose in this investigation). The addition of Ca(OH)2 not only improved the effectiveness of the AC treatment but also resulted in a significant rise in Lolium seed germination at the highest AC doses (60 and 80 g L(-1)). Considering the high salinity (7300 μS cm(-1)) of these wastewaters, low quantities of Ca(OH)2 may also exert a protective effect on soil structure counteracting the sodium-induced dispersion through the binding action of calcium cation on clays and organic matter. PMID:24289894

  2. Herbage intake and ruminal digestion of dairy cows grazed on perennial ryegrass pasture either in the morning or evening.

    PubMed

    Ueda, Koichiro; Mitani, Tomohiro; Kondo, Seiji

    2016-08-01

    This study aimed to clarify diurnal fluctuations of herbage intake, ruminal fermentation of herbage carbohydrates and proteins, and digesta particulate weight in the rumen of grazing dairy cows. Six ruminally cannulated, non-lactating dairy cows were grazed on perennial ryegrass/white clover pasture either in the morning (04.00 to 08.00 hours) or the evening (16.00 to 20.00 hours). Cows grazed in the evening spent more time (P < 0.01) and consumed more herbage (P < 0.01) compared with cows grazed in the morning. Higher (P < 0.05) daily mean concentrations of total volatile fatty acid, propionate and n-butyrate in rumen fluid were observed for cows grazed in the evening compared with cows grazed in the morning. Although cows grazed in the evening ingested more crude protein compared with cows grazed in the morning, no significant difference in NH3 -N concentration in rumen fluid was observed between them. The ratio of purine-derivative concentration to creatinine concentrations was higher (P < 0.01) in the urine of cows grazed in the evening than in cows grazed in the morning. These results clearly indicated that evening grazing was advantageous for dairy cows compared with morning grazing, in terms of ruminal fermentable energy intake and nitrogen utilization efficiency. PMID:26607997

  3. Simultaneous Influx and Efflux of Nitrate during Uptake by Perennial Ryegrass 1

    PubMed Central

    Morgan, M. A.; Volk, R. J.; Jackson, W. A.

    1973-01-01

    Experiments with intact plants of Lolium perenne previously grown with 14NO3− revealed significant efflux of this isotopic species when the plants were transferred to solutions of highly enriched 15NO3−. The exuded 14NO3− was subsequently reabsorbed when the ambient solutions were not replaced. When they were frequently replaced, continual efflux of the 14NO3− was observed. Influx of 15NO3− was significantly greater than influx of 14NO3− from solutions of identical NO3− concentration. Transferring plants to 14NO3− solutions after a six-hour period in 15NO3− resulted in efflux of the latter. Presence of Mg2+, rather than Ca2+, in the ambient 15NO3− solution resulted in a decidedly increased rate of 14NO3− efflux and a slight but significant increase in 15NO3− influx. Accordingly, net NO3− influx was slightly depressed. A model in accordance with these observations is presented; its essential features include a passive bidirectional pathway, an active uptake mechanism, and a pathway for recycling of endogenous NO3− within unstirred layers from the passive pathway to the active uptake site. PMID:16658313

  4. Toxicity of eight polycyclic aromatic compounds to red clover (Trifolium pratense), ryegrass (Lolium perenne), and mustard (Sinapsis alba).

    PubMed

    Sverdrup, Line E; Krogh, Paul Henning; Nielsen, Torben; Kjaer, Christian; Stenersen, Jørgen

    2003-12-01

    The effect of eight polycyclic aromatic compounds (PACs) on the seed emergence and early life-stage growth of three terrestrial plants (Sinapsis alba, Trifolium pratense and Lolium perenne) were studied in a greenhouse, using a Danish agricultural soil with an organic carbon content of 1.6%. After three weeks of exposure, seed emergence and seedling weight (fresh weight and dry weight) were determined. Exposure concentrations were verified with chemical analysis. The substances tested were four polycyclic aromatic hydrocarbons (fluoranthene, pyrene, phenanthrene and fluorene), the N-, S-, and O-substituted analogues of fluorene (carbazole, dibenzothiophene and dibenzofuran, respectively), and the quinoline representative acridine. Seedling growth was a far more sensitive endpoint than seed emergence for all substances. Concentrations estimated to give a 20% reduction of seedling fresh weight (EC20-values) ranged from 36 to 290 mgkg(-1) for carbazole, 43 to 93 mgkg(-1) for dibenzofuran, 37 to 110 mgkg(-1) for dibenzothiophene, 140 to 650 mgkg(-1) for fluoranthene, 55 to 380 mgkg(-1) for fluorene, 37 to 300 mgkg(-1) for phenanthrene, and 49 to 1300 mgkg(-1) for pyrene. For acridine, no toxicity was observed within the concentration range tested (1-1000 mgkg(-1)). As illustrated by the EC20-values, there was a rather large difference in sensitivity between the species, and T. pratense was the most sensitive of the species tested. PMID:14505722

  5. EPSPS Gene Amplification in Glyphosate-Resistant Italian Ryegrass (Lolium perenne ssp. multiflorum) Populations from Arkansas (United States).

    PubMed

    Salas, Reiofeli A; Scott, Robert C; Dayan, Franck E; Burgos, Nilda R

    2015-07-01

    Glyphosate-resistant Italian ryegrass was detected in Arkansas (United States) in 2007. In 2014, 45 populations were confirmed resistant in eight counties across the state. The level of resistance and resistance mechanisms in six populations were studied to assess the severity of the problem and identify alternative management approaches. Dose-response bioassays, glyphosate absorption and translocation experiments, herbicide target (EPSPS) gene sequence analysis, and gene amplification assays were conducted. The dose causing 50% growth reduction (GR50) was 7-19 times higher for the resistant population than for the susceptible standard. Uptake and translocation of (14)C-glyphosate were similar in resistant and susceptible plants, and no mutation in the EPSPS gene known to be associated with resistance to glyphosate was detected. Resistant plants contained from 11- to >100-fold more copies of the EPSPS gene than the susceptible plants, whereas the susceptible plants had only one copy of EPSPS. Plants surviving the recommended dose of glyphosate contained at least 10 copies. The EPSPS copy number was positively related to glyphosate resistance level (r = 80). Therefore, resistance to glyphosate in these populations is due to multiplication of the target site. Resistance mechanisms could be location-specific. Suppressing the mechanism for gene amplification may overcome resistance. PMID:25760654

  6. Enhanced remediation of chlorpyrifos by ryegrass (Lolium multiflorum) and a chlorpyrifos degrading bacterial endophyte Mezorhizobium sp. HN3.

    PubMed

    Jabeen, Hina; Iqbal, Samina; Ahmad, Fiaz; Afzal, Muhammad; Firdous, Sadiqa

    2016-01-01

    For effective remediation of contaminants, plant-endophyte partnership is a promising field to be explored. Generally endophytic bacteria assist their host plant by withstanding the stress induced by the contaminants. The objective of this study was to explore the suitability of plant-bacterial partnership for chlorpyrifos (CP) remediation using ryegrass and a CP degrading endophyte, Mesorhizobium sp. HN3 which belongs to plant growth promoting rhizobia. The inoculated yfp-tagged Mesorhizobium sp. HN3 efficiently colonized in the rhizosphere, enhanced plant growth and degradation of CP and its metabolite 3,5,6 trichloro-2-pyridinol (TCP). Significantly lower CP residues were observed in the roots and shoots of plants vegetated in inoculated soil which might be attributed to the efficient root colonization of HN3yfp. These results suggest the involvement of Mesorhizobium sp. HN3yfp in CP degradation inside the roots and rhizosphere of plants and further emphasize on the effectiveness of endophytic bacteria in stimulating the remediation of pesticide contaminants. This is the first report which demonstrates the efficacy of bacterial endophyte for degradation of CP residues taken up by the plant and enhanced remediation of chlorpyrifos contaminated soil. PMID:26248164

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

    PubMed Central

    Gasperl, Anna; Morvan-Bertrand, Annette; Prud’homme, Marie-Pascale; Roitsch, Thomas

    2015-01-01

    Despite the fact that fructans are the main constituent of water-soluble carbohydrates in forage grasses and cereal crops of temperate climates, little knowledge is available on the regulation of the enzymes involved in fructan metabolism. The analysis of enzyme activities involved in this process has been hampered by the low affinity of the fructan enzymes for sucrose and fructans used as fructosyl donor. Further, the analysis of fructan composition and enzyme activities is restricted to specialized labs with access to suited HPLC equipment and appropriate fructan standards. The degradation of fructan polymers with high degree of polymerization (DP) by fructan exohydrolases (FEHs) to fructosyloligomers is important to liberate energy in the form of fructan, but also under conditions where the generation of low DP polymers is required. Based on published protocols employing enzyme coupled endpoint reactions in single cuvettes, we developed a simple and fast kinetic 1-FEH assay. This assay can be performed in multi-well plate format using plate readers to determine the activity of 1-FEH against 1-kestotriose, resulting in a significant time reduction. Kinetic assays allow an optimal and more precise determination of enzyme activities compared to endpoint assays, and enable to check the quality of any reaction with respect to linearity of the assay. The enzyme coupled kinetic 1-FEH assay was validated in a case study showing the expected increase in 1-FEH activity during cold treatment. This assay is cost effective and could be performed by any lab with access to a plate reader suited for kinetic measurements and readings at 340 nm, and is highly suited to assess temporal changes and relative differences in 1-FEH activities. Thus, this enzyme coupled kinetic 1-FEH assay is of high importance both to the field of basic fructan research and plant breeding. PMID:26734049

  8. Simultaneous enhancement of methane production and methane content in biogas from waste activated sludge and perennial ryegrass anaerobic co-digestion: The effects of pH and C/N ratio.

    PubMed

    Dai, Xiaohu; Li, Xiaoshuai; Zhang, Dong; Chen, Yinguang; Dai, Lingling

    2016-09-01

    It is necessary to find an appropriate strategy to simultaneously enhance the methane production and methane content in biogas from waste activated sludge (WAS) and grass co-digestion. In this study an efficient strategy, i.e., adjusting the initial pH 12 and C/N ratio 17/1, for simultaneous enhancement of methane production and methane content in biogas from WAS and perennial ryegrass co-digestion was reported. Experimental results indicated that the maximal methane production was 310mL/gVSadd at the optimum conditions after 30-d anaerobic digestion, which was, respectively, about 1.5- and 3.8-fold of the sole WAS and sole perennial ryegrass anaerobic digestion. Meanwhile, the methane content in biogas was about 74%, which was much higher than that of sole WAS (64%) or sole perennial ryegrass (54%) anaerobic digestion. PMID:27259187

  9. Acclimation of photosynthesis to elevated CO{sub 2} under low-nitrogen nutrition is affected by the capacity for assimilate utilization. Perennial ryegrass under free-air CO{sub 2} enrichment

    SciTech Connect

    Rogers, A.; Bryant, J.; Raines, C.A.; Long, S.P.L.; Fischer, B.U.; Frehner, M.; Blum, H.; Long, S.P. |

    1998-10-01

    Acclimation of photosynthesis to elevated CO{sub 2} has previously been shown to be more pronounced when N supply is poor. Is this a direct effect of N or an indirect effect of N by limiting the development of sinks for photoassimilate? This question was tested by growing a perennial ryegrass (Lolium perenne) in the field under elevated (60 Pa) and current (36 Pa) partial pressures of CO{sub 2} (pCO{sub 2}) at low and high levels of N fertilization. Cutting of this herbage crop at 4- to 8-week intervals removed about 80% of the canopy, therefore decreasing the ratio of photosynthetic area to sinks for photoassimilate. Leaf photosynthesis, in vivo carboxylation capacity, carbohydrate, N, ribulose-1,5-biphosphate carboxylase/oxygenase, sedoheptulose-1,7-bisphosphatase, and chloroplastic fructose-1,6-bisphosphatase levels were determined for mature lamina during two consecutive summers, just before the cut, when the canopy was relatively large, growth at elevated pCO{sub 2} and low N resulted in significant decreases in carboxylation capacity and the amount of ribulose-1,5-biphosphate carboxylase/oxygenase protein. In high N there were no significant decreases in carboxylation capacity or proteins, but chloroplastic fructose-1,6-bisphosphatase protein levels increased significantly. Elevated pCO{sub 2} resulted in a marked and significant increase in leaf carbohydrate content at low N, but had no effect at high N. This acclimation at low N was absent after the harvest, when the canopy size was small. These results suggest that acclimation under low N is caused by limitation of sink development rather than being a direct effect of N supply on photosynthesis.

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

    PubMed Central

    Broadhurst, Catherine L.; Chaney, Rufus L.

    2016-01-01

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

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

    PubMed

    Broadhurst, Catherine L; Chaney, Rufus L

    2016-01-01

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

  12. Germplasm dynamics: the role of ecotypic diversity in shaping the patterns of genetic variation in Lolium perenne.

    PubMed

    Blackmore, T; Thorogood, D; Skøt, L; McMahon, R; Powell, W; Hegarty, M

    2016-01-01

    Perennial ryegrass (Lolium perenne) is the most widely grown temperate grass species globally. Intensive plant breeding in ryegrass compared to many other crops species is a relatively recent exercise (last 100 years) and provides an interesting experimental system to trace the extent, impact and trajectory of undomesticated ecotypic variation represented in modern ryegrass cultivars. To explore germplasm dynamics in Lolium perenne, 2199 SNPs were genotyped in 716 ecotypes sampled from 90 European locations together with 249 cultivars representing 33 forage/amenity accessions. In addition three pseudo-cross mapping populations (450 individual recombinants) were genotyped to create a consensus genetic linkage map. Multivariate analyses revealed strong differentiation between cultivars with a small proportion of the ecotypic variation captured in improved cultivars. Ryegrass cultivars generated as part of a recurrent selection programme (RSP) are strongly associated with a small number of geographically localised Italian ecotypes which were among the founders of the RSP. Changes in haplotype frequency revealed signatures of selection in genes putatively involved in water-soluble carbohydrate (WSC) accumulation (a trait selected in the RSP). Retrospective analysis of germplasm in breeding programmes (germplasm dynamics) provides an experimental framework for the identification of candidate genes for novel traits such as WSC accumulation in ryegrass. PMID:26935901

  13. Germplasm dynamics: the role of ecotypic diversity in shaping the patterns of genetic variation in Lolium perenne

    PubMed Central

    Blackmore, T.; Thorogood, D.; Skøt, L.; McMahon, R.; Powell, W.; Hegarty, M.

    2016-01-01

    Perennial ryegrass (Lolium perenne) is the most widely grown temperate grass species globally. Intensive plant breeding in ryegrass compared to many other crops species is a relatively recent exercise (last 100 years) and provides an interesting experimental system to trace the extent, impact and trajectory of undomesticated ecotypic variation represented in modern ryegrass cultivars. To explore germplasm dynamics in Lolium perenne, 2199 SNPs were genotyped in 716 ecotypes sampled from 90 European locations together with 249 cultivars representing 33 forage/amenity accessions. In addition three pseudo-cross mapping populations (450 individual recombinants) were genotyped to create a consensus genetic linkage map. Multivariate analyses revealed strong differentiation between cultivars with a small proportion of the ecotypic variation captured in improved cultivars. Ryegrass cultivars generated as part of a recurrent selection programme (RSP) are strongly associated with a small number of geographically localised Italian ecotypes which were among the founders of the RSP. Changes in haplotype frequency revealed signatures of selection in genes putatively involved in water-soluble carbohydrate (WSC) accumulation (a trait selected in the RSP). Retrospective analysis of germplasm in breeding programmes (germplasm dynamics) provides an experimental framework for the identification of candidate genes for novel traits such as WSC accumulation in ryegrass. PMID:26935901

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

    PubMed Central

    Han, K. J.; McCormick, M. E.; Derouen, S. M.; Blouin, D. C.

    2014-01-01

    In southeastern regions of the US, herbage systems are primarily based on grazing or hay feeding with low nutritive value warm-season perennial grasses. Nutritious herbage such as annual ryegrass (Lolium multiflorum Lam.) may be more suitable for preserving as baleage for winter feeding even with more intensive production inputs. Emerging in-line wrapped baleage storage systems featuring rapid wrapping and low polyethylene film requirements need to be tested for consistency of storing nutritive value of a range of annual ryegrass herbage. A ryegrass storage trial was conducted with 24-h wilted ‘Marshall’ annual ryegrass harvested at booting, heading and anthesis stages using three replicated in-line wrapped tubes containing ten round bales per tube. After a six-month storage period, nutritive value changes and fermentation end products differed significantly by harvest stage but not by bale location. Although wilted annual ryegrass exhibited a restricted fermentation across harvest stages characterized by high pH and low fermentation end product concentrations, butyric acid concentrations were less than 1 g/kg dry matter, and lactic acid was the major organic acid in the bales. Mold coverage and bale aroma did not differ substantially with harvest stage or bale location. Booting and heading stage-harvested ryegrass baleage were superior in nutritive value to anthesis stage-harvested herbage. Based on the investigated nutritive value and fermentation characteristics, individual bale location within in-line tubes did not significantly affect preservation quality of ryegrass round bale silages. PMID:25178371

  15. In vivo transmission of 'candidatus Phytoplasma ulmi' by Amplicephalus curtulus (Hemiptera: Cicadellidae) and its effect on ryegrass (Lolium multiflorum cv. tama).

    PubMed

    Arismendi, N L; Riegel, R; Carrillo, R

    2014-02-01

    In Chile, phytoplasmas have been reported in sugar beet, grapevine, peony, and Chilean shrubs. 'Candidatus Phytoplasma ulmi' have been detected in plants of Ugni molinae Turczanínow (Myrtaceae) and the leafhopper Amplicephalus curtulus Linnavuori & DeLong. We evaluated the possibility of phytoplasma transmission from native plants to grasses by A. curtulus and the possible effect on the plant hosts. Newly emerged adults were placed in cages with phytoplasma-infected U. molinae for 72 h (acquisition access period). These plants were then replaced by healthy ryegrasses for 20 d (latent period). They were again replaced for other healthy ryegrasses and were place in cages for 14, 7, and 1 d (inoculation access period [IAP]). After IAP, these plants were moved into different insect-free cages for 30 d, after which polymerase chain reaction (PCR) analyses were carried out. Phytoplasma-free insects on ryegrasses were considered as control treatments. Furthermore, plant height and leaf area were recorded for all treatments. After PCR, 46, 60, and 13% of the plants exposed to infected A. curtulus by 14, 7, and 1 d of IAP, respectively, were infected with 'Ca. Phytoplasma ulmi'. Similarly, plants exposed to an IAP of 14, 7, and 1 d with phytoplasma-infected leafhoppers showed a reduction in plant height of 19, 39, and 28% and leaf area of 302, 169, and 55%, respectively, in comparison to those exposed to phytoplasma-free leafhoppers. We showed that A. curtulus has the ability to transmit phytoplasma from U. molinae to ryegrasses, affecting ryegrass plant height and leaf area PMID:24665688

  16. Heat Shock Factor Genes of Tall Fescue and Perennial Ryegrass in Response to Temperature Stress by RNA-Seq Analysis

    PubMed Central

    Wang, Yan; Dai, Ya; Tao, Xiang; Wang, Jia-Zhen; Cheng, Hai-Yang; Yang, Hong; Ma, Xin-Rong

    2016-01-01

    Heat shock factors (Hsfs) are important regulators of stress-response in plants. However, our understanding of Hsf genes and their responses to temperature stresses in two Pooideae cool-season grasses, Festuca arundinacea, and Lolium perenne, is limited. Here we conducted comparative transcriptome analyses of plant leaves exposed to heat or cold stress for 10 h. Approximately, 30% and 25% of the genes expressed in the two species showed significant changes under heat and cold stress, respectively, including subsets of Hsfs and their target genes. We uncovered 74 Hsfs in F. arundinacea and 52 Hsfs in L. perenne, and categorized these genes into three subfamilies, HsfA, HsfB, and HsfC based on protein sequence homology to known Hsf members in model organisms. The Hsfs showed a strong response to heat and/or cold stress. The expression of HsfAs was elevated under heat stress, especially in class HsfA2, which exhibited the most dramatic responses. HsfBs were upregulated by the both temperature conditions, and HsfCs mainly showed an increase in expression under cold stress. The target genes of Hsfs, such as heat shock protein (HSP), ascorbate peroxidase (APX), inositol-3-phosphate synthase (IPS), and galactinol synthase (GOLS1), showed strong and unique responses to different stressors. We comprehensively detected Hsfs and their target genes in F. arundinacea and L. perenne, providing a foundation for future gene function studies and genetic engineering to improve stress tolerance in grasses and other crops. PMID:26793208

  17. Exploring the potential of phyllosilicate minerals as potassium fertilizers using sodium tetraphenylboron and intensive cropping with perennial ryegrass

    PubMed Central

    Li, Ting; Wang, Huoyan; Wang, Jing; Zhou, Zijun; Zhou, Jianmin

    2015-01-01

    In response to addressing potassium (K) deficiency in soil and decreasing agricultural production costs, the potential of K-bearing phyllosilicate minerals that can be directly used as an alternative K source has been investigated using sodium tetraphenylboron (NaTPB) extraction and an intensive cropping experiment. The results showed that the critical value of K-release rate and leaf K concentration was 3.30 g kg−1 h−1 and 30.64 g (kg dry matter)−1, respectively under the experimental conditions. According to this critical value, the maximum amount of released K that could be utilized by a plant with no K deficiency symptoms was from biotite (27.80 g kg−1) and vermiculite (5.58 g kg−1), followed by illite, smectite and muscovite with 2.76, 0.88 and 0.49 g kg−1, respectively. Ryegrass grown on phlogopite showed K deficiency symptoms during the overall growth period. It is concluded that biotite and vermiculite can be directly applied as a promising and sustainable alternative to the use of classical K fertilizers, illite can be utilized in combination with soluble K fertilizers, whereas muscovite, phlogopite and smectite may not be suitable for plant growth. Further field experiments are needed to assess the use of these phyllosilicate minerals as sources of K fertilizer. PMID:25782771

  18. Exploring the potential of phyllosilicate minerals as potassium fertilizers using sodium tetraphenylboron and intensive cropping with perennial ryegrass

    NASA Astrophysics Data System (ADS)

    Li, Ting; Wang, Huoyan; Wang, Jing; Zhou, Zijun; Zhou, Jianmin

    2015-03-01

    In response to addressing potassium (K) deficiency in soil and decreasing agricultural production costs, the potential of K-bearing phyllosilicate minerals that can be directly used as an alternative K source has been investigated using sodium tetraphenylboron (NaTPB) extraction and an intensive cropping experiment. The results showed that the critical value of K-release rate and leaf K concentration was 3.30 g kg-1 h-1 and 30.64 g (kg dry matter)-1, respectively under the experimental conditions. According to this critical value, the maximum amount of released K that could be utilized by a plant with no K deficiency symptoms was from biotite (27.80 g kg-1) and vermiculite (5.58 g kg-1), followed by illite, smectite and muscovite with 2.76, 0.88 and 0.49 g kg-1, respectively. Ryegrass grown on phlogopite showed K deficiency symptoms during the overall growth period. It is concluded that biotite and vermiculite can be directly applied as a promising and sustainable alternative to the use of classical K fertilizers, illite can be utilized in combination with soluble K fertilizers, whereas muscovite, phlogopite and smectite may not be suitable for plant growth. Further field experiments are needed to assess the use of these phyllosilicate minerals as sources of K fertilizer.

  19. Exploring the potential of phyllosilicate minerals as potassium fertilizers using sodium tetraphenylboron and intensive cropping with perennial ryegrass.

    PubMed

    Li, Ting; Wang, Huoyan; Wang, Jing; Zhou, Zijun; Zhou, Jianmin

    2015-01-01

    In response to addressing potassium (K) deficiency in soil and decreasing agricultural production costs, the potential of K-bearing phyllosilicate minerals that can be directly used as an alternative K source has been investigated using sodium tetraphenylboron (NaTPB) extraction and an intensive cropping experiment. The results showed that the critical value of K-release rate and leaf K concentration was 3.30 g kg(-1) h(-1) and 30.64 g (kg dry matter)(-1), respectively under the experimental conditions. According to this critical value, the maximum amount of released K that could be utilized by a plant with no K deficiency symptoms was from biotite (27.80 g kg(-1)) and vermiculite (5.58 g kg(-1)), followed by illite, smectite and muscovite with 2.76, 0.88 and 0.49 g kg(-1), respectively. Ryegrass grown on phlogopite showed K deficiency symptoms during the overall growth period. It is concluded that biotite and vermiculite can be directly applied as a promising and sustainable alternative to the use of classical K fertilizers, illite can be utilized in combination with soluble K fertilizers, whereas muscovite, phlogopite and smectite may not be suitable for plant growth. Further field experiments are needed to assess the use of these phyllosilicate minerals as sources of K fertilizer. PMID:25782771

  20. Prediction of enteric methane emissions from sheep offered fresh perennial ryegrass () using data measured in indirect open-circuit respiration chambers.

    PubMed

    Zhao, Y G; O'Connell, N E; Yan, T

    2016-06-01

    Development of effective methane (CH) mitigation strategies for grazing sheep requires accurate prediction tools. The present study aimed to identify key parameters influencing enteric CH emissions and develop prediction equations for enteric CH emissions from sheep offered fresh grass. The data used were collected from 82 sheep offered fresh perennial ryegrass () as sole diets in 6 metabolism experiments (data from non-grass-only diets were not used). Sheep were from breeds of Highlander, Texel, Scottish Blackface, and Swaledale at the age of 5 to 18 mo and weighing from 24.5 to 62.7 kg. Grass was harvested daily from 6 swards on contrasting harvest dates (May to December). Before the commencement of each study, the experimental sward was harvested at a residual height of 4 cm and allowed to grow for 2 to 4 wk. The feeding trials commenced when the grass sward was suitable to zero grazing (average grass height = 15 cm), thus offering grass of a quality similar to what grazing animals would receive under routine grazing management. Sheep were housed in individual pens for 14 d and then moved to individual calorimeter chambers for 4 d. Feed intake, fecal and urine outputs, and CH emissions were measured during the final 4 d. Data were analyzed using the REML procedure to develop prediction equations for CH emissions. Linear and multiple prediction equations were developed using BW, DMI, GE intake (GEI), and grass chemical concentrations (DM, OM, water-soluble carbohydrates [WSC], NDF, ADF, nitrogen [N], GE, DE, and ME) as explanatory variables. The mean CH production was 21.1 g/kg DMI or 0.062 MJ/MJ GEI. Dry matter intake and GEI were much more accurate predictors for CH emissions than BW ( < 0.001, = 0.86 and = 0.87 vs. = 0.09, respectively). Adding grass DE and ME concentrations and grass nutrient concentrations (e.g., OM, N, GE, NDF, and WSC) to the relationships between DMI or GEI and CH emissions improved prediction accuracy with values increased to 0

  1. ESI-Mass spectrometric and HPLC elucidation of a new ergot alkaloid from perennial ryegrass hay silage associated with bovine reproductive problems.

    PubMed

    Lehner, Andreas F; Duringer, Jennifer M; Estill, Charles T; Tobin, Thomas; Craig, A Morrie

    2011-10-01

    This case report involves four dairies in the Willamette Valley, Oregon, which experienced reproductive problems associated with the presence of a large, previously unidentified, peak eluting at 5 min in a standard ergovaline high-performance liquid chromatography assay of perennial ryegrass silage fed to those animals. Mycotoxin analysis of the silage was negative, as was serological screening of the herds for infectious bovine rhinotracheitis, bovine diarrhea virus and Leptospirosis, including culturing of urine for Leptospira hardjo hardjobovis. Prolactin concentrations were low in most cattle, consistent with ingestion of ergot alkaloids. We believe that this peak represents a novel ergot alkaloid-related compound due to its extractability with Ergosil, its detectability due to fluorescence, and its chromatographic retention between ergovaline (mw = 533) and ergotamine (mw = 581). Its molecular weight was calculated as 570 owing to the predominance of a m/z 593.5 ion in the full scan ESI(+)MS and its deduced tendency to complex with Na(+) (as m/z 593) or K(+) (as m/z 609) ions. We offer rationales for elucidation of the structure of this compound, with the closest starting point comprising an m.w. of 566-a fructofuranosyl-(2-1)-O-beta-D-fructofuranoside derivative of 6,7-secoergoline from Claviceps fusiformis. This m.w. requires modifications, such as reduction of two double bonds in the secoergoline component to give the target 570 m.w. Despite the lack of a definitive structure, the analysis herein provides a starting point for eventual elucidation of this apparently new ergot alkaloid, and to guide and encourage further investigation as to its association with endophyte toxicosis in livestock. PMID:21506724

  2. In Vitro and In Vivo Enhancement of Adipogenesis by Italian Ryegrass (Lolium multiflorum) in 3T3-L1 Cells and Mice

    PubMed Central

    Kim, Da Hye; Gun Roh, Sang; Lee, Jeong-Chae; Choi, Ki Choon

    2014-01-01

    Adipogenesis is very much important in improving the quality of meat in animals. The aim of the present study was to investigate the in vitro and in vivo adipogenesis regulation properties of Lolium multiflorum on 3T3-L1 pre-adipocytes and mice. Chemical composition of petroleum ether extract of L. multiflorum (PET-LM) confirmed the presence of fatty acids, such as α-linolenic acid, docosahexaenoic acid, oleic acid, docosatetraenoic acid, and caprylic acid, as the major compounds. PET-LM treatment increased viability, lipid accumulation, lipolysis, cell cycle progression, and DNA synthesis in the cells. PET-LM treatment also augmented peroxysome proliferator activated receptor (PPAR)-γ2, CCAAT/enhancer binding protein-α, adiponectin, adipocyte binding protein, glucose transporter-4, fatty acid synthase, and sterol regulatory element binding protein-1 expression at mRNA and protein levels in differentiated adipocytes. In addition, mice administered with 200 mg/kg body weight PET-LM for 8 weeks showed greater body weight than control mice. These findings suggest that PET-LM facilitates adipogenesis by stimulating PPARγ-mediated signaling cascades in adipocytes which could be useful for quality meat development in animals. PMID:24454838

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

    PubMed

    Valan Arasu, Mariadhas; Ilavenil, Soundharrajan; Kim, Da Hye; Gun Roh, Sang; Lee, Jeong-Chae; Choi, Ki Choon

    2014-01-01

    Adipogenesis is very much important in improving the quality of meat in animals. The aim of the present study was to investigate the in vitro and in vivo adipogenesis regulation properties of Lolium multiflorum on 3T3-L1 pre-adipocytes and mice. Chemical composition of petroleum ether extract of L. multiflorum (PET-LM) confirmed the presence of fatty acids, such as α-linolenic acid, docosahexaenoic acid, oleic acid, docosatetraenoic acid, and caprylic acid, as the major compounds. PET-LM treatment increased viability, lipid accumulation, lipolysis, cell cycle progression, and DNA synthesis in the cells. PET-LM treatment also augmented peroxysome proliferator activated receptor (PPAR)-γ2, CCAAT/enhancer binding protein-α, adiponectin, adipocyte binding protein, glucose transporter-4, fatty acid synthase, and sterol regulatory element binding protein-1 expression at mRNA and protein levels in differentiated adipocytes. In addition, mice administered with 200 mg/kg body weight PET-LM for 8 weeks showed greater body weight than control mice. These findings suggest that PET-LM facilitates adipogenesis by stimulating PPARγ-mediated signaling cascades in adipocytes which could be useful for quality meat development in animals. PMID:24454838

  4. Dispersal and post-dispersal predation of Italian ryegrass seed in unimproved pasture.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dispersal and post-dispersal predation of Italian ryegrass seed in unimproved pasture. Italian ryegrass (Lolium multiflorum L.) can be a productive and high-quality cool-season forage, but is considered a weed in some pastures. Italian ryegrass does not form a persistent seed bank and needs to prod...

  5. The photosynthetic acclimation of Lolium perenne growing in a free-air CO{sub 2} enrichment (FACE) system

    SciTech Connect

    Bryant, J.B. |

    1994-11-01

    Stands of Ryegrass (Lolium perenne L. cv. Bastion) were grown in the field at ambient or elevated (600{mu}mol/mol) CO{sub 2} concentration, high (560Kg/ha) or low (140Kg/ha) nitrogen addition and with a frequent (every 4 weeks) or infrequent (every 8 weeks) cutting regime. Plants were in the second year of a 3 year experiment. Exposure to elevated CO{sub 2} was carried out with a Free-Air CO{sub 2} Enrichment (FACE) system which provides the most {open_quote}realistic{close_quote} system of CO{sub 2} fumigation currently available. Elevated CO{sub 2} increased diurnal CO{sub 2} assimilation by between 34 and 88% whilst reducing rates of stomatal conductance by between 1 and 42%. However, analysis of the A vs. Ci response showed considerable acclimation of the photosynthetic apparatus in response to elevated CO{sub 2} - Vc{sub max} as an in vivo measure of RubisCO activity, decreased by between 29 and 35% in high CO{sub 2}, whilst J{sub max}, as a measure of the RubP regeneration capacity, showed no significant change. Two out of three additional perennial grassland species studied showed similar acclamatory behavior to Ryegrass. Diurnal assimilation rate, J{sub max} and, in most cases, Vc{sub max}, increased significantly directly after cutting of Ryegrass stands, but nitrogen treatment had little effect on any of these parameters. Neither stomatal density, stomatal index nor stomatal pore length of Ryegrass were significantly altered by growth in elevated CO{sub 2}. The results are discussed in terms of the limitation imposed on maximizing photosynthetic and growth responses of Ryegrass at elevated CO{sub 2}, by the ability of perennial species to increase long-term sink capacity under these conditions.

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

    PubMed

    Byrne, Stephen L; Nagy, Istvan; Pfeifer, Matthias; Armstead, Ian; Swain, Suresh; Studer, Bruno; Mayer, Klaus; Campbell, Jacqueline D; Czaban, Adrian; Hentrup, Stephan; Panitz, Frank; Bendixen, Christian; Hedegaard, Jakob; Caccamo, Mario; Asp, Torben

    2015-11-01

    Here we report the draft genome sequence of perennial ryegrass (Lolium perenne), an economically important forage and turf grass species that is widely cultivated in temperate regions worldwide. It is classified along with wheat, barley, oats and Brachypodium distachyon in the Pooideae sub-family of the grass family (Poaceae). Transcriptome data was used to identify 28 455 gene models, and we utilized macro-co-linearity between perennial ryegrass and barley, and synteny within the grass family, to establish a synteny-based linear gene order. The gametophytic self-incompatibility mechanism enables the pistil of a plant to reject self-pollen and therefore promote out-crossing. We have used the sequence assembly to characterize transcriptional changes in the stigma during pollination with both compatible and incompatible pollen. Characterization of the pollen transcriptome identified homologs to pollen allergens from a range of species, many of which were expressed to very high levels in mature pollen grains, and are potentially involved in the self-incompatibility mechanism. The genome sequence provides a valuable resource for future breeding efforts based on genomic prediction, and will accelerate the development of new varieties for more productive grasslands. PMID:26408275

  7. Molecular Characterization and Taxonomy of Lolium Latent Virus, a Novel Member of the Family Flexiviridae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lolium latent virus (LoLV) was recently detected in the United States for the first time (Maroon-Lango et al., 2006, Plant Disease 90:528) in ryegrass hybrids (Lolium perenne x multiflorum). The genome of one U.S. isolate, LoLV-US1, has now been fully sequenced. The positive strand genomic RNA is 76...

  8. Temperature and Plant Genotype Alter Alkaloid Concentrations in Ryegrass Infected with an Epichloë Endophyte and This Affects an Insect Herbivore.

    PubMed

    Hennessy, Louise M; Popay, Alison J; Finch, Sarah C; Clearwater, Michael J; Cave, Vanessa M

    2016-01-01

    Asexual Epichloë endophytes colonize agricultural forage grasses in a relationship which is mutually beneficial and provides the host plant with protection against herbivorous insects. The endophyte strain AR37 (Epichloë festucae var. lolii) produces epoxy-janthitrem alkaloids and is the only endophyte known to provide ryegrass with resistance against porina larvae (Wiseana cervinata (Walker)), a major pasture pest in cooler areas of New Zealand. This study examined the effect of temperature on concentrations of epoxy-janthitrems in AR37-infected ryegrass and determined how the resulting variations in concentration affected consumption, growth and survival of porina larvae. Twenty replicate pairs of perennial (Lolium perenne L.) and Italian ryegrass (L. multiflorum Lam.) plants with and without endophyte were prepared by cloning, with one of each pair grown at either high (20°C) or low (7°C) temperature. After 10 weeks, herbage on each plant was harvested, divided into leaf and pseudostem, then freeze dried and ground. Leaf and pseudostem material was then incorporated separately into semi-synthetic diets which were fed to porina larvae in a bioassay over 3 weeks. Epoxy-janthitrem concentrations within the plant materials and the semi-synthetic diets were analyzed by high performance liquid chromatography. AR37-infected ryegrass grown at high temperature contained high in planta concentrations of epoxy-janthitrem (30.6 μg/g in leaves and 83.9 μg/g in pseudostems) that had a strong anti-feedant effect on porina larvae when incorporated into their diets, reducing their survival by 25-42% on pseudostems. In comparison, in planta epoxy-janthitrem concentrations in AR37-infected ryegrass grown at low temperature were very low (0.67 μg/g in leaves and 7.4 μg/g in pseudostems) resulting in a small anti-feedant effect in perennial but not in Italian ryegrass. Although alkaloid concentrations were greatly reduced by low temperature this reduction did not occur until

  9. Temperature and Plant Genotype Alter Alkaloid Concentrations in Ryegrass Infected with an Epichloë Endophyte and This Affects an Insect Herbivore

    PubMed Central

    Hennessy, Louise M.; Popay, Alison J.; Finch, Sarah C.; Clearwater, Michael J.; Cave, Vanessa M.

    2016-01-01

    Asexual Epichloë endophytes colonize agricultural forage grasses in a relationship which is mutually beneficial and provides the host plant with protection against herbivorous insects. The endophyte strain AR37 (Epichloë festucae var. lolii) produces epoxy-janthitrem alkaloids and is the only endophyte known to provide ryegrass with resistance against porina larvae (Wiseana cervinata (Walker)), a major pasture pest in cooler areas of New Zealand. This study examined the effect of temperature on concentrations of epoxy-janthitrems in AR37-infected ryegrass and determined how the resulting variations in concentration affected consumption, growth and survival of porina larvae. Twenty replicate pairs of perennial (Lolium perenne L.) and Italian ryegrass (L. multiflorum Lam.) plants with and without endophyte were prepared by cloning, with one of each pair grown at either high (20°C) or low (7°C) temperature. After 10 weeks, herbage on each plant was harvested, divided into leaf and pseudostem, then freeze dried and ground. Leaf and pseudostem material was then incorporated separately into semi-synthetic diets which were fed to porina larvae in a bioassay over 3 weeks. Epoxy-janthitrem concentrations within the plant materials and the semi-synthetic diets were analyzed by high performance liquid chromatography. AR37-infected ryegrass grown at high temperature contained high in planta concentrations of epoxy-janthitrem (30.6 μg/g in leaves and 83.9 μg/g in pseudostems) that had a strong anti-feedant effect on porina larvae when incorporated into their diets, reducing their survival by 25–42% on pseudostems. In comparison, in planta epoxy-janthitrem concentrations in AR37-infected ryegrass grown at low temperature were very low (0.67 μg/g in leaves and 7.4 μg/g in pseudostems) resulting in a small anti-feedant effect in perennial but not in Italian ryegrass. Although alkaloid concentrations were greatly reduced by low temperature this reduction did not occur

  10. Implementation of Genomic Prediction in Lolium perenne (L.) Breeding Populations

    PubMed Central

    Grinberg, Nastasiya F.; Lovatt, Alan; Hegarty, Matt; Lovatt, Andi; Skøt, Kirsten P.; Kelly, Rhys; Blackmore, Tina; Thorogood, Danny; King, Ross D.; Armstead, Ian; Powell, Wayne; Skøt, Leif

    2016-01-01

    Perennial ryegrass (Lolium perenne L.) is one of the most widely grown forage grasses in temperate agriculture. In order to maintain and increase its usage as forage in livestock agriculture, there is a continued need for improvement in biomass yield, quality, disease resistance, and seed yield. Genetic gain for traits such as biomass yield has been relatively modest. This has been attributed to its long breeding cycle, and the necessity to use population based breeding methods. Thanks to recent advances in genotyping techniques there is increasing interest in genomic selection from which genomically estimated breeding values are derived. In this paper we compare the classical RRBLUP model with state-of-the-art machine learning techniques that should yield themselves easily to use in GS and demonstrate their application to predicting quantitative traits in a breeding population of L. perenne. Prediction accuracies varied from 0 to 0.59 depending on trait, prediction model and composition of the training population. The BLUP model produced the highest prediction accuracies for most traits and training populations. Forage quality traits had the highest accuracies compared to yield related traits. There appeared to be no clear pattern to the effect of the training population composition on the prediction accuracies. The heritability of the forage quality traits was generally higher than for the yield related traits, and could partly explain the difference in accuracy. Some population structure was evident in the breeding populations, and probably contributed to the varying effects of training population on the predictions. The average linkage disequilibrium between adjacent markers ranged from 0.121 to 0.215. Higher marker density and larger training population closely related with the test population are likely to improve the prediction accuracy. PMID:26904088

  11. Allelopathic effect of Bromus spp. and Lolium spp. shoot extracts on some crops.

    PubMed

    Lehoczky, E; Nelima, M Okumu; Szabó, R; Szalai, A; Nagy, P

    2011-01-01

    Allelopathy is an untapped resource for weed control in crops that could give good possibilities for environmentally sound, integrated crop production. Allelopathy is defined as the direct or indirect harmful or beneficial effects of one plant on another through the production of chemical compounds, called allelochemicals, which escape into the environment. Allelochemicals can be produced by weeds and affect crops, and the reverse is also true. Allelopathic interactions include weed-weed, weed-crop, and crop-crop. Allelopathy offers potential for selective biological weed control for instance weed-suppressing crops and the use of plant residues in cropping systems, allelopathic rotational crops, or companion plants with allelopathic potential. Bromus species occur in many habitats in temperate regions of the world, including America, Eurasia, Australia, and Africa. The genus Lolium is one of the most important forage grasses. The weed species usually grow in the same production zones as wheat and are considered weeds since they parasitize wheat fields. Some of the weed species in these two genus have been reported to have allelopathic effect. One of the methods that has been successful in studying allelopathic activity are bioassays. Laboratory experiments were conducted to determine allelopathic effect of watery shoot extracts of four weed species of the Poaceae family, namely Bromus rigidus, Bromus diandrus, Lolium multiflorum and Lolium temulentum on germination and growth of winter wheat (Triticum aestivum L.), spring barley (Hordeum vulgare L.), corn (Zea mays L), perennial ryegrass (Lolium perenne L.), bean (Phaseolus sp.) and sunflower (Helianthus annuus L.) and on each other. The experiment was carried out during the period March 2010 to October 2010. Twenty five seeds were put into one Petri-dish on filter paper, adding 15ml of extract to each in four repeats. The germination took place in a Binder-type thermostat in the dark. The timing of germination was

  12. Metabolic changes and associated cytokinin signals in response to nitrate assimilation in roots and shoots of Lolium perenne.

    PubMed

    Roche, Jessica; Love, Jonathan; Guo, Qianqian; Song, Jiancheng; Cao, Mingshu; Fraser, Karl; Huege, Jan; Jones, Chris; Novák, Ondřej; Turnbull, Matthew H; Jameson, Paula E

    2016-04-01

    The efficiency of inorganic nitrogen (N) assimilation is a critical component of fertilizer use by plants and of forage production in Lolium perenne, an important pasture species worldwide. We present a spatiotemporal description of nitrate use efficiency in terms of metabolic responses and carbohydrate remobilization, together with components of cytokinin signal transduction following nitrate addition to N-impoverished plants. Perennial ryegrass (L. perenne cv. Grasslands Nui) plants were grown for 10 weeks in unfertilized soil and then treated with nitrate (5 mM) hydroponically. Metabolomic analysis by gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry revealed a dynamic interaction between N and carbon metabolism over a week-long time course represented by the relative abundance of amino acids, tricarboxylic acid intermediates and stored water-soluble carbohydrates (WSCs). The initial response to N addition was characterized by a rapid remobilization of carbon stores from the low-molecular weight WSC, along with an increase in N content and assimilation into free amino acids. Subsequently, the shoot became the main source of carbon through remobilization of a large pool of high-molecular weight WSC. Associated quantification of cytokinin levels and expression profiling of putative cytokinin response regulator genes by quantitative reverse transcription polymerase chain reaction support a role for cytokinin in the mediation of the response to N addition in perennial ryegrass. The presence of high levels of cis-zeatin-type cytokinins is discussed in the context of hormonal homeostasis under the stress of steady-state N deficiency. PMID:26661753

  13. Pathotype-specific QTL for stem rust resistance in Lolium perenne.

    PubMed

    Pfender, W F; Slabaugh, M E

    2013-05-01

    A genetic map populated with RAD and SSR markers was created from F1 progeny of a stem rust-susceptible and stem rust-resistant parent of perennial ryegrass (Lolium perenne). The map supplements a previous map of this population by having markers in common with several other Lolium spp. maps including EST-SSR anchor markers from a consensus map published by other researchers. A QTL analysis was conducted with disease severity and infection type data obtained by controlled inoculation of the population with each of two previously characterized pathotypes of Puccinia graminis subsp. graminicola that differ in virulence to different host plant genotypes in the F1 population. Each pathotype activated a specific QTL on one linkage group (LG): qLpPg1 on LG7 for pathotype 101, or qLpPg2 on LG1 for pathotype 106. Both pathotypes also activated a third QTL in common, qLpPg3 on LG6. Anchor markers, present on a consensus map, were located in proximity to each of the three QTL. These QTL had been detected also in previous experiments in which a genetically heterogeneous inoculum of the stem rust pathogen activated all three QTL together. The results of this and a previous study are consistent with the involvement of the pathotype-specific QTL in pathogen recognition and the pathotype-nonspecific QTL in a generalized resistance response. By aligning the markers common to other published reports, it appears that two and possibly all three of the stem rust QTL reported here are in the same general genomic regions containing some of the L. perenne QTL reported to be activated in response to the crown rust pathogen (P. coronata). PMID:23361523

  14. Italian ryegrass for the phytoremediation of solutions polluted with terbuthylazine.

    PubMed

    Mimmo, Tanja; Bartucca, Maria Luce; Del Buono, Daniele; Cesco, Stefano

    2015-01-01

    The phytoextraction capacity of Italian ryegrass (Lolium multiflorum L.) to remove terbuthylazine (TBA) from aqueous solution has been assessed using a plant-based biotest (RHIZOtest). Three TBA concentrations (0.5, 1.0 and 2.0 mg L(-1)) were chosen to evaluate the tolerance capacity of the ryegrass. Even though the treatments negatively affected plants, they were able to remove up to 30-40% of TBA. In addition, some enzymatic activities involved in the response to TBA-induced stress were determined. Glutathione S-transferase (GST) has been activated with a TBA-dose dependent trend; ascorbate peroxidase (APX) activities have been induced within the first hours after the treatments, followed by decreases or disappearance in plants exposed to two higher dosages. In conclusion, this case-study highlights that the combination of ryegrass and RHIZOtest resulted to be effective in the remediation of aqueous solutions polluted by TBA. PMID:24954449

  15. Morphological traits associated with weed-suppressive ability of winter wheat against Italian ryegrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed-suppressive wheat (Triticum aestivum L.) cultivars have been suggested as a complement to chemical and cultural methods of weed control. The objectives of this study were to assess the range of weed-suppressive ability against Italian ryegrass [Lolium perenne L. ssp. multiflorum (Lam.) Husnot] ...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  18. Stocker growth on rye and ryegrass pastures affects subsequent feedlot gains and carcass traits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stocker calves were stocked on annual rye (Secale cereale L.) and ryegrass (Lolium multiflorum Lam.) pastures using stocking strategies (STK) to create graded levels of gain to assess subsequent growth rates, feedlot performance, and carcass traits. During two consecutive years, yearling Angus, Here...

  19. Cloning and characterization of a salt stress-inducible small GTPase gene from the model grass species Lolium temulentum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A gene encoding a small GTP binding protein (smGTP) related to the Rab2 gene family of GTPases was identified during the analysis of a salt stress suppression subtractive hybridization (SSH) expression library from the model grass species Lolium temulentum L. (Darnel ryegrass). The smGTP gene was fo...

  20. Effects of amendments on copper, cadmium, and lead phytoextraction by Lolium perenne from multiple-metal contaminated solution.

    PubMed

    Gunawardana, B; Singhal, N; Johnson, A

    2011-03-01

    Chemical amendments can increase metal uptake by plant roots and translocation to shoots, however their effectiveness can be influenced by the presence of other amendments and metal ions in a multiple-metal environment. A range of amendments and combinations were tested to explore their effect on phytoextraction of Cu, Cd, and Pb by perennial ryegrass (Lolium perenne) from solutions containing one or more of these metals. The amendments studied included EDDS (an aminopolycarboxylic acid), histidine (an amino acid), citric acid (an organic acid), rhamnolipid (a biosurfactant) and sulfate (an inorganic ligand). For all amendment treatments, the presence of multiple metals in solution reduced shoot concentrations of Cd and Cu, while Pb levels in shoots were generally enhanced by the presence of Cu. Although slightly toxic to the plants, EDDS (1 mM) was the most effective individual amendment for enhancing shoot metal uptake and translocation from solution without significantly reducing biomass yield. The combination Rhm+Cit+EDDS resulted in the highest shoot metal concentrations of all the treatments but also caused severe phytotoxicity. Amendment combinations Rhm+His and Sulf+Cit were less toxic for plant growth while moderately enhancing metal mass accumulation in shoots and thus could be considered as alternative treatments for enhanced phytoextraction. PMID:21598788

  1. First report of Fusarium graminearum, F. asiaticum and F. cortaderiae as head blight pathogens of annual ryegrass in Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Members of the Fusarium graminearum species complex (FGSC) cause Fusarium head blight (FHB) of small grains and several grasses, including annual ryegrass (Lolium multiflorum Lam.), an important forage crop, but also a common weed in wheat, rice and maize agroecosystem in southern Brazil. Although i...

  2. Amino acid composition of a manure-amended soil: rhizospheric and non-rhizospheric differences in a greenhouse ryegrass study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of poultry manure application on soil concentrations of 19 amino acids and two amino sugars were evaluated in a greenhouse pot study of ryegrass (Lolium perenne). Amino compounds were extracted and analyzed by anion chromatography and pulsed amperometric detection 4, 8, and 16 wk after m...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  4. Bioenergy production from perennial energy crops: a consequential LCA of 12 bioenergy scenarios including land use changes.

    PubMed

    Tonini, Davide; Hamelin, Lorie; Wenzel, Henrik; Astrup, Thomas

    2012-12-18

    In the endeavor of optimizing the sustainability of bioenergy production in Denmark, this consequential life cycle assessment (LCA) evaluated the environmental impacts associated with the production of heat and electricity from one hectare of Danish arable land cultivated with three perennial crops: ryegrass (Lolium perenne), willow (Salix viminalis) and Miscanthus giganteus. For each, four conversion pathways were assessed against a fossil fuel reference: (I) anaerobic co-digestion with manure, (II) gasification, (III) combustion in small-to-medium scale biomass combined heat and power (CHP) plants and IV) co-firing in large scale coal-fired CHP plants. Soil carbon changes, direct and indirect land use changes as well as uncertainty analysis (sensitivity, MonteCarlo) were included in the LCA. Results showed that global warming was the bottleneck impact, where only two scenarios, namely willow and Miscanthus co-firing, allowed for an improvement as compared with the reference (-82 and -45 t CO₂-eq. ha⁻¹, respectively). The indirect land use changes impact was quantified as 310 ± 170 t CO₂-eq. ha⁻¹, representing a paramount average of 41% of the induced greenhouse gas emissions. The uncertainty analysis confirmed the results robustness and highlighted the indirect land use changes uncertainty as the only uncertainty that can significantly change the outcome of the LCA results. PMID:23126612

  5. SSRs transferability and genetic diversity of three allogamous ryegrass species.

    PubMed

    Guo, Zhi-Hui; Fu, Kai-Xin; Zhang, Xin-Quan; Zhang, Cheng-Lin; Sun, Ming; Huang, Ting; Peng, Yan; Huang, Lin-Kai; Yan, Yan-Hong; Ma, Xiao

    2016-02-01

    Simple sequence repeat (SSR) markers are widely applied in studies of plant molecular genetics due to their abundance in the genome, codominant nature, and high repeatability. However, microsatellites are not always available for the species to be studied and their isolation could be time- and cost-consuming. To investigate transferability in cross-species applications, 102 primer pairs previously developed in ryegrass and tall fescue were amplified across three allogamous ryegrass species including Lolium rigidum, Lolium perenne and Lolium multiflorum. Their highly transferability (100%) were evidenced. While, most of these markers were multiple loci, only 17 loci were selected for a robust, single-locus pattern, which may be due to the recentness of the genome duplication or duplicated genomic regions, as well as speciation. A total of 87 alleles were generated with an average of 5.1 per locus. The mean polymorphism information content (PIC) and observed heterozygosity (Ho) values at genus was 0.5532 and 0.5423, respectively. Besides, analysis of molecular variance (AMOVA) revealed that all three levels contributed significantly to the overall genetic variation, with the species level contributing the least (P<0.001). Also, the unweighted pair group method with arithmetic averaging dendrogram (UPGMA), Bayesian model-based STRUCTURE analysis and the principal coordinate analysis (PCoA) showed that accessions within species always tended to the same cluster firstly and then to related species. The results showed that these markers developed in related species are transferable efficiently across species, and likely to be useful in analyzing genetic diversity. PMID:26874459

  6. A simulation model for epidemics of stem rust in ryegrass seed crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A simulation model (STEMRUST_G, named for stem rust of grasses) was created for stem rust (caused by Puccinia graminis subsp. graminicola) in perennial ryegrass grown to maturity as a seed crop. The model has a daily time step and is driven by weather data and an initial input of disease severity fr...

  7. Effects of poultry manure on phosphorus availability to perennial ryegrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil phosphorus (P) exists in numerous forms that differ in plant availability. High-P organic fertilizers, including poultry manure (PM), can alter the balance of these soil P forms and may affect plant nutrient status. To investigate the effects of PM on soil P distribution and plant utilization...

  8. Removal of a combination of endocrine disruptors from aqueous systems by seedlings of radish and ryegrass.

    PubMed

    Gattullo, C Eliana; Cunha, Bruno Barboza; Rosa, André H; Loffredo, Elisabetta

    2013-01-01

    Endocrine disruptors (EDs) are widespread in the environment, especially aquatic systems, and cause dangerous effects on wildlife and humans. This work was aimed to assess the capacity of radish (Raphanus sativus L.) and ryegrass (Lolium perenne L.) seedlings to tolerate and remove two combinations of EDs containing bisphenol A (BPA), 17alpha-ethynilestradiol (EE2), and linuron from four aqueous media: distilled water, a solution of natural organic matter (NOM), a lake water and a river water. Seeds of the two species were germinated in each contaminated medium and, at the end of germination, the seedling growth was evaluated by biometric measurements and residual EDs were quantified by chromatographic analysis. Biometric measurements revealed that the phytotoxicity of the two combinations of EDs depended on the medium used. Radish showed a discrete tolerance in distilled water and lake water but was inhibited in the solution of NOM and river water. Ryegrass was negatively affected mainly in river water. The concentration of each ED appeared significantly reduced in all media in the presence of seedlings of both species, but not in the blanks without plants. In 5 days, radish removed up to 88% of BPA, 100% of EE2 and 42% of linuron, and in 6 days ryegrass removed up to 92% of BPA, 74% of EE2 and 16% of linuron. The considerable removal capacity of radish and ryegrass in all media tested encourages the use of phytoremediation to remove EDs from waters. PMID:24617071

  9. Utilization of flow cytometry for festulolium breeding (Lolium multiflorum (2x) × Festuca arundinacea (6x))

    PubMed Central

    Akiyama, Yukio; Ueyama, Yasufumi; Hamada, Seiya; Kubota, Akito; Kato, Daisuke; Yamada-Akiyama, Hitomi; Takahara, Yoshinori; Fujimori, Masahiro

    2016-01-01

    Festulolium is a hybrid between Festuca and Lolium species that has valuable agronomic traits from both grass species. The purpose of our breeding program is to produce hexaploid festulolium that introduces tolerance to summer depression into Italian ryegrass (Lolium multiflorum) by crossing it with tall fescue (Festuca arundinacea). However, we found the DNA ploidy of hexaploids was not stable and was reduced in successive generations. We aimed to find out how to obtain stable high-ploidy festulolium. F1 hybrids of L. multiflorum and F. arundinacea were produced. The F3 generation was produced from putative hexaploid F2 individuals by open pollination. The F4 to F6 generations were obtained by polycrossing. The DNA ploidy levels of F2 to F6 individuals were estimated by flow cytometry. Cytological characteristics of the F5 and F6 individuals were investigated by FISH and GISH. The DNA ploidy level of hexaploid festulolium was reduced and stabilized at almost the same level as a tetraploid. Seed fertility was inversely correlated with an increase in ploidy level. GISH revealed no preferential Lolium transmission. FISH with a telomere probe revealed that counting the exact number of chromosomes in festulolium was difficult. DNA ploidy level was strongly correlated with the number of chromosomes. PMID:27162495

  10. Utilization of flow cytometry for festulolium breeding (Lolium multiflorum (2x) × Festuca arundinacea (6x)).

    PubMed

    Akiyama, Yukio; Ueyama, Yasufumi; Hamada, Seiya; Kubota, Akito; Kato, Daisuke; Yamada-Akiyama, Hitomi; Takahara, Yoshinori; Fujimori, Masahiro

    2016-03-01

    Festulolium is a hybrid between Festuca and Lolium species that has valuable agronomic traits from both grass species. The purpose of our breeding program is to produce hexaploid festulolium that introduces tolerance to summer depression into Italian ryegrass (Lolium multiflorum) by crossing it with tall fescue (Festuca arundinacea). However, we found the DNA ploidy of hexaploids was not stable and was reduced in successive generations. We aimed to find out how to obtain stable high-ploidy festulolium. F1 hybrids of L. multiflorum and F. arundinacea were produced. The F3 generation was produced from putative hexaploid F2 individuals by open pollination. The F4 to F6 generations were obtained by polycrossing. The DNA ploidy levels of F2 to F6 individuals were estimated by flow cytometry. Cytological characteristics of the F5 and F6 individuals were investigated by FISH and GISH. The DNA ploidy level of hexaploid festulolium was reduced and stabilized at almost the same level as a tetraploid. Seed fertility was inversely correlated with an increase in ploidy level. GISH revealed no preferential Lolium transmission. FISH with a telomere probe revealed that counting the exact number of chromosomes in festulolium was difficult. DNA ploidy level was strongly correlated with the number of chromosomes. PMID:27162495

  11. Transcriptional Profiles of Drought-Related Genes in Modulating Metabolic Processes and Antioxidant Defenses in Lolium multiflorum

    PubMed Central

    Pan, Ling; Zhang, Xinquan; Wang, Jianping; Ma, Xiao; Zhou, Meiliang; Huang, LinKai; Nie, Gang; Wang, Pengxi; Yang, Zhongfu; Li, Ji

    2016-01-01

    Drought is a major environmental stress that limits growth and development of cool-season annual grasses. Drought transcriptional profiles of resistant and susceptible lines were studied to understand the molecular mechanisms of drought tolerance in annual ryegrass (Lolium multiflorum L.). A total of 4718 genes exhibited significantly differential expression in two L. multiflorum lines. Additionally, up-regulated genes associated with drought response in the resistant lines were compared with susceptible lines. Gene ontology enrichment and pathway analyses revealed that genes partially encoding drought-responsive proteins as key regulators were significantly involved in carbon metabolism, lipid metabolism, and signal transduction. Comparable gene expression was used to identify the genes that contribute to the high drought tolerance in resistant lines of annual ryegrass. Moreover, we proposed the hypothesis that short-term drought have a beneficial effect on oxidation stress, which may be ascribed to a direct effect on the drought tolerance of annual ryegrass. Evidence suggests that some of the genes encoding antioxidants (HPTs, GGT, AP, 6-PGD, and G6PDH) function as antioxidant in lipid metabolism and signal transduction pathways, which have indispensable and promoting roles in drought resistance. This study provides the first transcriptome data on the induction of drought-related gene expression in annual ryegrass, especially via modulation of metabolic homeostasis, signal transduction, and antioxidant defenses to improve drought tolerance response to short-term drought stress. PMID:27200005

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

    PubMed

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

    2011-06-01

    The objective was to determine the effect of including silages of annual ryegrass (Lolium multiflorum) intercropped with winter vetch (Vicia villosa) (ARG-VV) or with common vetch (Vicia sativa) (ARG-VS) compared with maize silage (MS) on milk yield and milk composition of dairy cows grazing cultivated perennial ryegrass-white clover pastures with supplemented concentrate during the dry season. Six Holstein dairy cows with a mean yield of 19.0 kg/cow/day at the beginning of the experiment were randomly assigned to a 3 × 3 repeated Latin square. Treatments were: 8 h/day intensive grazing, 3.6 kg of dry matter (DM) per cow per day of concentrate plus MS, and ARG-VV or ARG-VS ad libitum at a stocking rate of 3.0 cows/ha for three experimental periods of 3 weeks each. Milk yield (MY) and milk composition, live weight and body condition score as well as silage and concentrate intakes were recorded during the third week of each experimental period, and pasture intake was estimated indirectly from utilised metabolisable energy. Economic analysis was obtained by preparing partial budgets. There were no statistical differences (P > 0.10) in MY, milk fat or protein content nor for live weight, but there was significant difference (P < 0.10) in body condition score. There were non-statistical differences in silage DM intake (P < 0.11); however, significant differences (P < 0.10) were obtained for estimated grazed herbage intake whilst no differences for total DM intake. Slightly higher economic returns (10%) were obtained with ARG-VS over MS, and this was 7% higher than ARG-VV. It is concluded that ARG-VS could be an option for complementing grazing for small-scale dairy production systems in the dry season as it is comparable to MS in animal performance and slightly better in economic terms. PMID:21327716

  13. Measured and Simulated Nitrous Oxide Emissions from Ryegrass- and Ryegrass/White Clover-Based Grasslands in a Moist Temperate Climate

    PubMed Central

    Li, Dejun; Lanigan, Gary; Humphreys, James

    2011-01-01

    There is uncertainty about the potential reduction of soil nitrous oxide (N2O) emission when fertilizer nitrogen (FN) is partially or completely replaced by biological N fixation (BNF) in temperate grassland. The objectives of this study were to 1) investigate the changes in N2O emissions when BNF is used to replace FN in permanent grassland, and 2) evaluate the applicability of the process-based model DNDC to simulate N2O emissions from Irish grasslands. Three grazing treatments were: (i) ryegrass (Lolium perenne) grasslands receiving 226 kg FN ha−1 yr−1 (GG+FN), (ii) ryegrass/white clover (Trifolium repens) grasslands receiving 58 kg FN ha−1 yr−1 (GWC+FN) applied in spring, and (iii) ryegrass/white clover grasslands receiving no FN (GWC-FN). Two background treatments, un-grazed swards with ryegrass only (G–B) or ryegrass/white clover (WC–B), did not receive slurry or FN and the herbage was harvested by mowing. There was no significant difference in annual N2O emissions between G–B (2.38±0.12 kg N ha−1 yr−1 (mean±SE)) and WC-B (2.45±0.85 kg N ha−1 yr−1), indicating that N2O emission due to BNF itself and clover residual decomposition from permanent ryegrass/clover grassland was negligible. N2O emissions were 7.82±1.67, 6.35±1.14 and 6.54±1.70 kg N ha−1 yr−1, respectively, from GG+FN, GWC+FN and GWC-FN. N2O fluxes simulated by DNDC agreed well with the measured values with significant correlation between simulated and measured daily fluxes for the three grazing treatments, but the simulation did not agree very well for the background treatments. DNDC overestimated annual emission by 61% for GG+FN, and underestimated by 45% for GWC-FN, but simulated very well for GWC+FN. Both the measured and simulated results supported that there was a clear reduction of N2O emissions when FN was replaced by BNF. PMID:22028829

  14. Lolium perenne grasslands may function as a sink for atmospheric carbon dioxide

    SciTech Connect

    Ginkel, J.H. van; Whitmore, A.P.; Gorissen, A.

    1999-10-01

    Model calculations and scenario studies suggest the existence of a considerable positive feedback between temperature and CO{sub 2} levels in the atmosphere. Rising temperatures are supposed to increase decomposition of soil organic C leading to increased production of CO{sub 2} and this extra CO{sub 2} induces a positive feedback by raising the temperature still further. Evidence was found that negative feedback mechanisms also exist; more primary production is allocated to roots as atmospheric CO{sub 2} rises and these roots decompose more slowly than roots grown at ambient CO{sub 2} levels. Experimental data partly obtained with {sup 14}C-techniques were applied in a grassland C model. The model results show that at an atmospheric CO{sub 2} concentration of 700 {micro}L L{sup {minus}1} increased below ground C storage will be more than sufficient to balance the increased decomposition of soil organic C in a ryegrass (Lolium perenne L.) grassland soil. Once a doubling of the present atmospheric CO{sub 2} concentration has been reached, C equivalent to 55% of the annual CO{sub 2} increase above 1 ha ryegrass can be withdrawn from the atmosphere. This indicates that grassland soils represent a significant sink for rising atmospheric CO{sub 2}.

  15. Amendments promote the development of Lolium perenne in soils affected by historical copper smelting operations.

    PubMed

    Goecke, Paul; Ginocchio, Rosanna; Mench, Michel; Neaman, Alexander

    2011-07-01

    The Puchuncaví valley, central Chile, has been exposed to aerial emissions from a copper smelter. Nowadays, soils in the surroundings are sparsely-vegetated, acidic, and metal-contaminated, and their remediation is needed to reduce environmental risks. We assessed effectiveness of lime, fly ash, compost, and iron grit as amendments to immobilize Cu in soils and promote plant growth. Amended soils were cultivated with Lolium perenne for 60 days under controlled conditions. Total dissolved Cu and Cu2+ activity in the soil solution, ryegrass biomass, and Cu accumulation in plant tissues were measured. Addition of lime and fly ash decreased Cu concentrations and Cu2+ activity in the soil solution, increased plant biomass, and reduced shoot Cu concentration below 22 mg kg(-1) (the phytotoxicity threshold for the species). The most effective amendment with respect to the shoot biomass yield was a combination of lime and compost. Water content of the substrate and the K accumulation were positively correlated with the compost application rate. Compost combined with iron grit decreased dissolved Cu concentrations during the period of highest solubility, i.e., during the first 60 days after the compost application. However, iron grit incorporation into soils amended with lime and compost decreased the shoot biomass of ryegrass. PMID:21972502

  16. Does leaf manipulation affect leaf appearance in italian ryegrass (Lolium multiflorum Lam.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mechanical stimuli such as rubbing, shaking, or flexing plants can alter their growth rates and morphologies. Plant response to mechanical stress can result in delayed plant growth, reduced leaf size, shorten and thicken stems, and reduced yields. Repeated measurements, such as leaf counting or me...

  17. Windrow burning eliminates Italian Ryegrass (Lolium perenne ssp. multiflorum) seed viability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Burning of crop residues that have been concentrated behind the harvest combine (windrowed) is one of several harvest weed seed control strategies that have been developed and evaluated in Australia to address the widespread evolution of multiple herbicide resistance in annual weeds. Herbicide-resis...

  18. Virus induced gene silencing in Lolium temulentum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lolium temulentum L. is valuable as a model species for studying abiotic stress in closely related forage and turf grasses, many of which are polyploid outcrossing species. As with most monocot species, Agrobacterium-mediated transformation of L. temulentum is still challenging, time consuming and n...

  19. Interplanting Annual Ryegrass, Wheat, Oat, and Corn to Mitigate Iron Deficiency in Dry Beans

    PubMed Central

    Omondi, Emmanuel Chiwo; Kniss, Andrew R.

    2014-01-01

    This study evaluated whether grass intercropping can be used to alleviate Fe deficiency chlorosis in dry beans (Phaseolus vulgaris L.) grown in high pH, calcareous soils with low organic matter. Field studies were conducted at the University of Wyoming Sustainable Agriculture Research and Extension Center in 2009 and 2010. Black- and navy beans were grown alone or intercropped with annual ryegrass (Lolium multiflorum Lam.), oat (Avena sativa L.), corn (Zea mays L.), or spring wheat (Triticum aestivum L.) in a two-factor factorial strip-plot randomized complete block design. All four grass species increased chlorophyll intensity in dry beans. However, grass species did not increase iron (Fe) concentration in dry bean tissues suggesting inefficient utilization of Fe present in the dry bean tissues. In 2009, nitrate-nitrogen (NO3-N) and manganese (Mn) concentration in bean tissue were greater in bean monoculture than in grass intercropped beans. Bean monoculture also had greater soil NO3-N concentrations than grass intercropped treatments. In 2009, grass intercrops reduced dry bean yield >25% compared to bean monoculture. Annual ryegrass was the least competitive of the four annual grass species. This suggests that competition from grasses for nutrients, water, or light may have outweighed benefits accruing from grass intercropping. Additional studies are required to determine the appropriate grass and dry bean densities, as well as the optimum time of grass removal. PMID:25536084

  20. Interplanting annual ryegrass, wheat, oat, and corn to mitigate iron deficiency in dry beans.

    PubMed

    Omondi, Emmanuel Chiwo; Kniss, Andrew R

    2014-01-01

    This study evaluated whether grass intercropping can be used to alleviate Fe deficiency chlorosis in dry beans (Phaseolus vulgaris L.) grown in high pH, calcareous soils with low organic matter. Field studies were conducted at the University of Wyoming Sustainable Agriculture Research and Extension Center in 2009 and 2010. Black- and navy beans were grown alone or intercropped with annual ryegrass (Lolium multiflorum Lam.), oat (Avena sativa L.), corn (Zea mays L.), or spring wheat (Triticum aestivum L.) in a two-factor factorial strip-plot randomized complete block design. All four grass species increased chlorophyll intensity in dry beans. However, grass species did not increase iron (Fe) concentration in dry bean tissues suggesting inefficient utilization of Fe present in the dry bean tissues. In 2009, nitrate-nitrogen (NO3-N) and manganese (Mn) concentration in bean tissue were greater in bean monoculture than in grass intercropped beans. Bean monoculture also had greater soil NO3-N concentrations than grass intercropped treatments. In 2009, grass intercrops reduced dry bean yield >25% compared to bean monoculture. Annual ryegrass was the least competitive of the four annual grass species. This suggests that competition from grasses for nutrients, water, or light may have outweighed benefits accruing from grass intercropping. Additional studies are required to determine the appropriate grass and dry bean densities, as well as the optimum time of grass removal. PMID:25536084

  1. Perennial roots to immortality.

    PubMed

    Munné-Bosch, Sergi

    2014-10-01

    Maximum lifespan greatly varies among species, and it is not strictly determined; it can change with species evolution. Clonal growth is a major factor governing maximum lifespan. In the plant kingdom, the maximum lifespans described for clonal and nonclonal plants vary by an order of magnitude, with 43,600 and 5,062 years for Lomatia tasmanica and Pinus longaeva, respectively. Nonclonal perennial plants (those plants exclusively using sexual reproduction) also present a huge diversity in maximum lifespans (from a few to thousands of years) and even more interestingly, contrasting differences in aging patterns. Some plants show a clear physiological deterioration with aging, whereas others do not. Indeed, some plants can even improve their physiological performance as they age (a phenomenon called negative senescence). This diversity in aging patterns responds to species-specific life history traits and mechanisms evolved by each species to adapt to its habitat. Particularities of roots in perennial plants, such as meristem indeterminacy, modular growth, stress resistance, and patterns of senescence, are crucial in establishing perenniality and understanding adaptation of perennial plants to their habitats. Here, the key role of roots for perennial plant longevity will be discussed, taking into account current knowledge and highlighting additional aspects that still require investigation. PMID:24563283

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

    PubMed Central

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

    2014-01-01

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

  3. Doppler ultrasonography for evaluating vascular responses to ergopeptine alkaloids in livestock

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ergot alkaloids are produced by non-spore producing fungal endophytes that infect certain species of grasses, most notably tall fescue [Lolium arundinaceum (Schreb.) Darbysh.] and perennial ryegrass (Lolium perenne L.), and the spore producing Claviceps spp. that infect seed heads of certain grasses...

  4. Decontamination activity of ryegrass exudates towards bisphenol A in the absence and presence of dissolved natural organic matter.

    PubMed

    Gattullo, C Eliana; Kiersch, Kristian; Eckhardt, Kai-Uwe; Baum, Christel; Leinweber, Peter; Loffredo, Elisabetta

    2015-01-01

    Bisphenol A (BPA) is an endocrine disruptor compound widespread in terrestrial and aquatic systems of urbanized and industrialized regions. This study evaluated the capacity of ryegrass (Lolium perenne) aqueous exudates to degrade BPA at a concentration of 10 mg L(-1) both in the absence and in the presence of an organic fraction often coexisting with plant exudates, i.e., natural organic matter (NOM), tested at a concentration of 20 mg L(-1). In exudates alone, BPA degradation ceased after one day from the product addition when residual BPA resulted 65% of the initial BPA, whereas in exudates with the addition of NOM the degradation process continued for 4 days when residual BPA resulted 49%. Measurements of peroxidase and laccase activities in exudates suggested a significant involvement of these enzymes in BPA degradation. This finding was further confirmed by the almost complete absence of BPA degradation in aqueous exudates strongly acidified. In some BPA-contaminated exudates, chromatographic analysis revealed the presence of a newly formed compound identified as a BPA oxidation product by Fourier transform - ion cyclotron resonance mass spectrometry analysis. In conclusion, ryegrass exudates possess a relevant decontamination capacity towards BPA which persists and appears to be enhanced by the addition of NOM. PMID:25174419

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

    PubMed

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

    2009-02-15

    The applicability of biodegradable amendments in phytoremediation to increase the uptake of uranium (U), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb) and zinc (Zn) by Indian mustard (Brassica juncea) and ryegrass (Lolium perenne) was tested in a greenhouse experiment. Plants were cultivated during one month on two soils with naturally or industrially increased contaminant levels of U. Treatments with citric acid, NH4-citrate/citric acid, oxalic acid, S,S-ethylenediamine disuccinic acid (EDDS) or nitrilotriacetic acid (NTA) at a rate of 5 mmol kg(-1) dry soil caused increases in soil solution concentrations that were up to 18 times higher for U and up to 1570 times higher for other heavy metals, compared to the controls. Shoot concentrations increased to a much smaller extent. With EDDS, 19-, 34-, and 37-fold increases were achieved in shoots of Indian mustard for U, Pb and Cu, respectively. The increases in plant uptake of Cd, Cr and Zn were limited to a factor of four at most. Ryegrass generally extracted less U and metals than Indian mustard. Despite a marked increase of U and metal concentrations in shoots after addition of amendments, the estimated time required to obtain an acceptable reduction in soil contaminant concentrations was impractically long. Only for Cu and Zn in one of the studied soils, could the Flemish standards for clean soil theoretically be attained in less than 100 years. PMID:19054545

  6. Effect of cadmium on microbial activity and a ryegrass crop in two semiarid soils.

    PubMed

    Moreno, José L; Sanchez-Marín, Antonio; Hernández, Teresa; García, Carlos

    2006-05-01

    Soil pollution with Cd is an environmental problem common in the world, and it is necessary to establish what Cd concentrations in soil could be dangerous to its fertility from toxicity effects and the risk of transference of this element to plants and other organisms of the food chain. In this study, we assessed Cd toxicity on soil microorganisms and plants in two semiarid soils (uncultivated and cultivated). Soil ATP content, dehydrogenase activity, and plant growth were measured in the two soils spiked with concentrations ranging from 3 to 8000 mg Cd/kg soil and incubated for 3 h, 20 days, and 60 days. The Cd concentrations that produced 5% 10%, and 50% inhibition of each of the two soil microbiological parameter studied (ecological dose, ED, values) were calculated using two different mathematical models. Also, the effect of Cd concentration on plant growth of ryegrass (Lolium perenne, L.) was studied in the two soils. The Cd ED values calculated for soil dehydrogenase activity and ATP content were higher in the agricultural soils than in the bare soil. For ATP inhibition, higher ED values were calculated than for dehydrogenase activity inhibition. The average yields of ryegrass were reduced from 5.03 to 3.56 g in abandoned soil and from 4.21 to 1.15 g in agricultural soil with increasing concentrations of Cd in the soil. Plant growth was totally inhibited in abandoned and agricultural soils at Cd concentrations above 2000 and 5000 mg/kg soil, respectively. There was a positive correlation between the concentration of Cd in the plants and the total or DTPA-extractable concentrations of Cd in the soil. PMID:16485164

  7. Differentiating glyphosate-resistant and glyphosate-sensitive Italian ryegrass using hyperspectral imagery

    NASA Astrophysics Data System (ADS)

    Lee, Matthew A.; Huang, Yanbo; Nandula, Vijay K.; Reddy, Krishna N.

    2014-05-01

    Glyphosate based herbicide programs are most preferred in current row crop weed control practices. With the increased use of glyphosate, weeds, including Italian ryegrass (Lolium multiflorum), have developed resistance to glyphosate. The identification of glyphosate resistant weeds in crop fields is critical because they must be controlled before they reduce the crop yield. Conventionally, the method for the identification with whole plant or leaf segment/disc shikimate assays is tedious and labor-intensive. In this research, we investigated the use of high spatial resolution hyperspectral imagery to extract spectral curves derived from the whole plant of Italian ryegrass to determine if the plant is glyphosate resistant (GR) or glyphosate sensitive (GS), which provides a way for rapid, non-contact measurement for differentiation between GR and GS weeds for effective site-specific weed management. The data set consists of 226 greenhouse grown plants (119 GR, 107 GS), which were imaged at three and four weeks after emergence. In image preprocessing, the spectral curves are normalized to remove lighting artifacts caused by height variation in the plants. In image analysis, a subset of hyperspectral bands is chosen using a forward selection algorithm to optimize the area under the receiver operating characteristic (ROC) between GR and GS plants. Then, the dimensionality of selected bands is reduced using linear discriminant analysis (LDA). Finally, the maximum likelihood classification was conducted for plant sample differentiation. The results show that the overall classification accuracy is between 75% and 80% depending on the age of the plants. Further refinement of the described methodology is needed to correlate better with plant age.

  8. Efficiency of green waste compost and biochar soil amendments for reducing lead and copper mobility and uptake to ryegrass.

    PubMed

    Karami, Nadia; Clemente, Rafael; Moreno-Jiménez, Eduardo; Lepp, Nicholas W; Beesley, Luke

    2011-07-15

    Green waste compost and biochar amendments were assessed for their assistance in regulating the mobility of copper (Cu) and lead (Pb) and the resultant uptake of these metals into vegetation. The amendments were mixed with a heavily Cu and Pb contaminated soil (600 and 21,000 mg kg(-1), respectively) from a former copper mine in Cheshire (UK), on a volume basis both singly and in combination in greenhouse pot trials. Ryegrass (Lolium perenne L. var. Cadix) was grown for the following 4 months during which biomass, metals in soil pore water and plant uptake were measured in three consecutive harvests. Very high Pb concentrations in pore water from untreated soil (>80 mg l(-1)) were reduced furthest by compost amendment (<5 mg l(-1)) whereas biochar was the more effective treatment at reducing pore water Cu concentrations. Duly, ryegrass shoot Cu levels were reduced and large, significant reductions in shoot Pb levels were observed after biochar and compost amendments, respectively during successive harvests. However, because green waste compost singly and in combination with biochar vividly enhanced biomass yields, harvestable amounts of Pb were only significantly reduced by the compost amendment which had reduced shoot Pb levels furthest. The low biomass of ryegrass with biochar amendment meant that this was the only amendment which did not significantly increase harvestable amounts of Cu. Therefore the two amendments have opposing metal specific suitability for treating this contaminated soil regarding whether it is a maximum reduction in plant tissue metal concentration or a maximum reduction in harvestable amount of metal that is required. PMID:21565444

  9. Toxicity of endophyte-infected ryegrass hay containing high ergovaline level in lactating ewes.

    PubMed

    Zbib, N; Repussard, C; Tardieu, D; Priymenko, N; Domange, C; Guerre, P

    2015-08-01

    The symbiotic association of var. (formerly named ) with perennial ryegrass () leads to the production of ergovaline (EV) and lolitrem B (LB) that are toxic for livestock. The objectives of this study were to determine the effects of feeding endophyte-infected ryegrass (SE+) hay on 16 lactating ewes (BW 80 ± 10 kg) in comparison with endophyte-free ryegrass (SE-) hay to investigate the putative mechanisms of action of EV and LB and to evaluate their persistence in milk and animal tissues. The mean EV and LB concentrations in SE+ hay were 851 and 884 μg/kg DM, respectively, whereas these alkaloids were below the limit of detection in SE- hay. No effect of SE+ was observed on animal health and skin temperature whereas prolactin decreased and significant differences between hays were observed from d 7 to 28 of the study ( < 0.03) but had no effect on milk production. Hematocrit and biochemical analyses of plasma revealed no significant difference between SE+ and SE-, whereas cortisol concentration differed significantly on d 28 ( = 0.001). Measurement of oxidative damage and antioxidant enzyme activities in plasma, liver, and kidneys revealed a slight increase in some enzyme activities involved in defense against oxidative damage in the SE+ fed ewes. Slight variations in the activities of hepatic and kidney flavin monooxygenase enzymes were observed, whereas in the kidney, glutathione -transferase activity decreased significantly ( = 0.002) in the SE+ fed ewes, whereas uridine diphosphate glucuronosyltransferase activity increased ( = 0.001). After 28 d of exposure of ewes to the SE+ hay, low EV and LB concentrations were measured in tissues. The highest concentration of EV was observed in the liver (0.68 μg/kg) whereas fat contained the highest concentration of LB (2.39 μg/kg). Both toxins were also identified at the trace level in milk. PMID:26440189

  10. Denitrification and Nitrate Consumption in an Herbaceous Riparian Area and Perennial Ryegrass Seed Field

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Riparian ecosystems have the capacity to lower NO3- concentrations in groundwater entering from non-point agricultural sources. The microbial processes responsible for decreases in riparian groundwater NO3- concentrations in the Willamette Valley of Oregon are not well understood. Our objective was...

  11. Soil Carbon Budget for Annual and Perennial Ryegrass Grown For Seed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There much interest in carbon (C) sequestration (C accounting) in cropping systems due the potential for agriculture to participate in ‘Cap and Trade’ opportunities, or purely as a matter of understanding soil quality. In this report we have constructed carbon budgets for two temperate grass species...

  12. Insect seed predation as a factor in Italian ryegrass persistence

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Italian ryegrass can be a productive and high-quality cool-season forage. However, as an annual, it does not form a persistent seed bank and needs to be managed to produce sufficient seed for effective re-establishment. Before the re-seeding dynamics of Italian ryegrass can be modeled, an underst...

  13. Solubilization of beta-glucan synthases from the membranes of cultured ryegrass endosperm cells.

    PubMed

    Henry, R J; Stone, B A

    1982-06-01

    beta-Glucan synthases were solubilized by treating membrane preparations from suspension-cultured ryegrass (lolium multiflorum) endosperm cells with detergents. Of the seven detergents tested only digitonin and octyl glucoside dissociated active synthases from the membranes. The digitonin-solubilized enzymes produced 1,4-beta-glucans and 1,3:1,4-beta-glucans, whereas the digitonin-insoluble enzymes produced, in addition, 1,3-beta-glucans. Chromatography of the digitonin-solubilized beta-glucan synthases on DEAE-Sepharose resulted in their partial purification. The octyl glucoside-solubilized enzymes produced more 1,3-beta-glucans than did the membrane-bound preparations. These results suggest that the 1,3-beta-glucan synthase is a separate enzyme and is not involved in 1,3:1,4-beta-glucan synthesis. Digitonin not only dissociated synthases from the membranes, but also stimulated synthase activity. This effect may be related to the inhibition by digitonin of glucosyl transfer from UDP-glucose to form steryl glucosides. PMID:6214254

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

    NASA Astrophysics Data System (ADS)

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

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

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

    SciTech Connect

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

    1999-12-01

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

  16. Factors Influencing beta-Glucan Synthesis by Particulate Enzymes from Suspension-Cultured Lolium multiflorum Endosperm Cells.

    PubMed

    Henry, R J; Stone, B A

    1982-03-01

    Particulate enzymes from suspension-cultured ryegrass (Lolium multiflorum Lam.) endosperm cells incorporated glucosyl residues from UDP-glucose and GDP-glucose into beta-glucans. Three types of beta-glucans were produced from UDP-glucose: 1,3-beta-glucan; 1,4-beta-glucan; and mixed-linkage 1,3;1,4-beta-glucan. As in other systems, relatively more 1,4-beta-glucan was produced from a low (10 micromolar) UDP-glucose concentration, and relatively more 1,3-beta-glucan was produced from a high (1 millimolar) UDP-glucose concentration. However, in ryegrass, 1,3;1,4-beta-glucan represented a major proportion of the products at both low and high UDP-glucose concentrations. The arrangement of linkages in the 1,3;1,4-beta-glucan was different at the two concentrations; at the low UDP-glucose concentration, more sequences of three consecutive 1,4-linkages were produced.The effects of pH, temperature, and metal ion concentrations on incorporation were dependent on the UDP-glucose concentration. At the low UDP-glucose concentration, incorporation into all three types of beta-glucan increased with increasing pH. At the high UDP-glucose concentration, 1,3-beta-glucan was the major product at pH 7 and below; 1,4-beta-glucan synthesis was optimal at pH 8; and synthesis of 1,3;1,4-beta-glucan was greatest above pH 8.With 10 micromolar GDP-glucose as substrate, 1,4-beta-glucan, but no 1,3;1,4-beta-glucan, was produced. Incorporation from either UDP-glucose or GDP-glucose was not influenced by the presence of the other. PMID:16662263

  17. Analysis of Antioxidant Enzyme Activity and Antioxidant Genes Expression During Germination of Two Different Genotypes of Lolium multiflorum Under Salt Tolerance.

    PubMed

    Wang, Xia; Ma, Xiao; Xinquan-Zhang; Linkai-Huang; Li, Zhou; Nie, Wenzhi-Xu Gang

    2016-01-01

    Annual ryegrass (Lolium multiflorum) is widely used as a cool-season forage grass for its luxuriant growth, palatable and high digestible. To investigate the salt tolerance mechanism in annual ryegrass under salt stress, salt-tolerant genotype 'R102-3' and salt-sensitive genotype 'Tetragold' were subject to 300mmol/L NaCl in a controlled growth chamber for 12 days. The results showed high concentrations of NaCl decreased relative water content (RWC), and increased the electrolyte leakage (EL) in both genotypes. However the 'Tetragold' had a greater increased extent of malondialdehyde (MDA) and EL than in 'R102-3', in contrast, the activities of Superoxide (SOD), Peroxidase (POD), Catalase (CAT) and Ascorbate peroxidase (APX) were higher in salt resistant compared to sensitive ones. For ensure the accurate of qRT-PCR, we used RefFinder to choose the most stably reference genes eEF1A(s) and GAPDH to normalize the antioxidant genes expression data. The results indicated that higher expression of Fe-SOD, Mn-SOD, Chl-Cu/Zn SOD, Cyt-Cu/Zn SOD, POD and CAT in 'R102-3' when compared with 'Tetragold', which may play an important role in defensed damage of Reactive oxygen species (ROS) under salt stress. Thus, the salt-tolerant genotype could effectively resist oxidative damage induced by salt tress relative to salt-sensitive genotype. PMID:26972970

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

    PubMed Central

    Loureiro, Iñigo; Escorial, María-Concepción; Chueca, María-Cristina

    2016-01-01

    The transfer of herbicide resistance genes by pollen is a major concern in cross-pollinated species such as annual ryegrass (Lolium rigidum). A two-year study was conducted in the greenhouse, under favorable conditions for pollination, to generate information on potential maximum cross-pollination. This maximum cross-pollination rate was 56.1%. A three-year field trial was also conducted to study the cross-pollination rates in terms of distance and orientation to an herbicide-resistant pollen source. Under field conditions, cross-pollination rates varied from 5.5% to 11.6% in plants adjacent to the pollen source and decreased with increasing distances (1.5 to 8.9% at 15 m distance and up to 4.1% at 25 m in the downwind direction). Environmental conditions influenced the cross-pollination both under greenhouse and field conditions. Data were fit to an exponential decay model to predict gene flow at increasing distances. This model predicted an average gene flow of 7.1% when the pollen donor and recipient plants were at 0 m distance from each other. Pollen-mediated gene flow declined by 50% at 16.7 m from the pollen source, yet under downwind conditions gene flow of 5.2% was predicted at 25 m, the farthest distance studied. Knowledge of cross-pollination rates will be useful for assessing the spread of herbicide resistance genes in L. rigidum and in developing appropriate strategies for its mitigation. PMID:27336441

  19. Current efforts to develop perennial wheat and domesticate Thinopyrum intermedium as a perennial grain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Land Institute is developing a new perennial grain by domesticating the perennial grass Thinopyrum intermedium (intermediate wheatgrass). In 1983, intermediate wheatgrass was selected for domestication by the Rodale Research Center (Kutztown, Penn., USA). Nearly 100 species of perennial grasse...

  20. Perennial Grain and Oilseed Crops.

    PubMed

    Kantar, Michael B; Tyl, Catrin E; Dorn, Kevin M; Zhang, Xiaofei; Jungers, Jacob M; Kaser, Joe M; Schendel, Rachel R; Eckberg, James O; Runck, Bryan C; Bunzel, Mirko; Jordan, Nick R; Stupar, Robert M; Marks, M David; Anderson, James A; Johnson, Gregg A; Sheaffer, Craig C; Schoenfuss, Tonya C; Ismail, Baraem; Heimpel, George E; Wyse, Donald L

    2016-04-29

    Historically, agroecosystems have been designed to produce food. Modern societies now demand more from food systems-not only food, fuel, and fiber, but also a variety of ecosystem services. And although today's farming practices are producing unprecedented yields, they are also contributing to ecosystem problems such as soil erosion, greenhouse gas emissions, and water pollution. This review highlights the potential benefits of perennial grains and oilseeds and discusses recent progress in their development. Because of perennials' extended growing season and deep root systems, they may require less fertilizer, help prevent runoff, and be more drought tolerant than annuals. Their production is expected to reduce tillage, which could positively affect biodiversity. End-use possibilities involve food, feed, fuel, and nonfood bioproducts. Fostering multidisciplinary collaborations will be essential for the successful integration of perennials into commercial cropping and food-processing systems. PMID:26789233

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

    PubMed Central

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

    2011-01-01

    Two field trials were conducted between 2008 and 2010 in Maryland to evaluate the ability of an Italian ryegrass (IR) (Lolium multiflorum) cover crop to reduce populations of plant-parasitic nematodes while enhancing beneficial nematodes, soil mites and arthropods in the foliage of a no-till soybean (Glycine max) planting. Preplant treatments were: 1) previous year soybean stubble (SBS); and 2) herbicide-killed IR cover crop + previous year soybean stubble (referred to as IR). Heterodera glycines population densities were very low and no significant difference in population densities of H. glycines or Pratylenchus spp. were observed between IR and SBS. Planting of IR increased abundance of bacterivorous nematodes in 2009. A reverse trend was observed in 2010 where SBS had higher abundance of bacterivorous nematodes and nematode richness at the end of the cover cropping period. Italian ryegrass also did not affect insect pests on soybean foliage. However, greater populations of spiders were found on soybean foliage in IR treatments during both field trials. Potential causes of these findings are discussed. PMID:23430284

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

    NASA Astrophysics Data System (ADS)

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

    2009-04-01

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

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

    PubMed

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

    2016-06-01

    In the present study, the toxic effect of decabromodiphenyl ether (BDE-209), an important brominated fire retardant, on soil was evaluated by amending with different concentrations (0 mg/kg, 1 mg/kg, 10 mg/kg, and 500 mg/kg dry wt) for 40 d. The activities of 3 soil enzymes (urease, catalase, and alkaline phosphatase) were measured as the principal assessment endpoints. Meanwhile, the effects of natural environmental factors, such as light conditions and soil biota, on BDE-209 intoxication were studied. For the latter, 30 earthworms (Metaphire guillelmi) with fully matured clitella or ryegrass (Lolium perenne) with fully matured leaves were exposed in soil amended with BDE-209. The activities of the soil enzymes were adversely affected by BDE-209, especially for the high-concentration treatments, with greater adverse effects in the dark than in the light. The presence of earthworms reduced toxicity to BDE-209, whereas ryegrass did not. The calculated integrated biomarker response index, which provides a general indicator of the health status of test species by combining different biomarker signals, further validated these findings. Moreover, the antioxidant status (oxidant-antioxidant balance) of these 2 biota was assessed. Results indicated that BDE-209 significantly affected the activities of antioxidant enzymes (superoxide dismutase and catalase) and enhanced the levels of malondialdehyde in both species. The present study may facilitate a better understanding of the toxicity of BDE-209 toward the soil environment. Environ Toxicol Chem 2016;35:1349-1357. © 2015 SETAC. PMID:26448514

  4. Ryegrass pasture combined with partial total mixed ration reduces enteric methane emissions and maintains the performance of dairy cows during mid to late lactation.

    PubMed

    Dall-Orsoletta, Aline C; Almeida, João Gabriel R; Carvalho, Paulo C F; Savian, Jean V; Ribeiro-Filho, Henrique M N

    2016-06-01

    The inclusion of grazed pasture in dairy feeding systems based on a total mixed ration (TMR) reduces feed costs, benefits herd health, and reduces environmental impact. The present study aimed to evaluate the effect of ryegrass pasture combined with a partial TMR on enteric methane emissions, dry matter intake (DMI), and performance of dairy cows from mid to late lactation. The experimental treatments included 100% TMR (control), partial TMR + 6h of continuous grazing (0900-1500 h), and partial TMR + 6h of grazing that was divided into 2 periods of 3h each that took place after milking (0900-1200 h; 1530-1830 h). Twelve F1 cows (Holstein × Jersey; 132±44 DIM) were divided into 6 lots and distributed in a 3×3 Latin square design with 3 periods of 21 d (15 d of adaptation and 6 d of evaluation). Ryegrass (Lolium multiflorum Lam.) pasture was used, and the TMR was composed of 80% corn silage, 18% soybean meal, and 2% mineral and vitamin mixture, based on dry matter. The same mixture was used for cows with access to pasture. The total DMI, milk production, and 4% fat-corrected milk were similar for all cows; however, the pasture DMI (7.4 vs. 6.0kg/d) and grazing period (+ 40 min/d) were higher in cows that had access to pasture for 2 periods of 3h compared with those that grazed for a continuous 6-h period. Methane emission was higher (656 vs. 547g/d) in confined cows than in those that received partial TMR + pasture. The inclusion of annual ryegrass pasture in the diet of dairy cows maintained animal performance and reduced enteric methane emissions. The percentage of grazed forage in the cows' diet increased when access to pasture was provided in 2 periods after the morning and afternoon milking. PMID:27016830

  5. The janthitrems: fluorescent tremorgenic toxins produced by Penicillium janthinellum isolates from ryegrass pastures.

    PubMed Central

    Gallagher, R T; Latch, G C; Keogh, R G

    1980-01-01

    New tremorgenic mycotoxins named janthitrem A, B, and C (molecular weights 601, 585, and 569, respectively) were produced by more than half of 21 Penicillium janthinellum isolates obtained from ryegrass pastures involved in ryegrass staggers outbreaks in sheep. PMID:7356319

  6. Fungal endophyte infection of ryegrass reprograms host metabolism and alters development.

    PubMed

    Dupont, Pierre-Yves; Eaton, Carla J; Wargent, Jason J; Fechtner, Susanne; Solomon, Peter; Schmid, Jan; Day, Robert C; Scott, Barry; Cox, Murray P

    2015-12-01

    Beneficial associations between plants and microbes play an important role in both natural and agricultural ecosystems. For example, associations between fungi of the genus Epichloë, and cool-season grasses are known for their ability to increase resistance to insect pests, fungal pathogens and drought. However, little is known about the molecular changes induced by endophyte infection. To study the impact of endophyte infection, we compared the expression profiles, based on RNA sequencing, of perennial ryegrass infected with Epichloë festucae with noninfected plants. We show that infection causes dramatic changes in the expression of over one third of host genes. This is in stark contrast to mycorrhizal associations, where substantially fewer changes in host gene expression are observed, and is more similar to pathogenic interactions. We reveal that endophyte infection triggers reprogramming of host metabolism, favouring secondary metabolism at a cost to primary metabolism. Infection also induces changes in host development, particularly trichome formation and cell wall biogenesis. Importantly, this work sheds light on the mechanisms underlying enhanced resistance to drought and super-infection by fungal pathogens provided by fungal endophyte infection. Finally, our study reveals that not all beneficial plant-microbe associations behave the same in terms of their effects on the host. PMID:26305687

  7. Control of the gray field slug during annual ryegrass establishment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weather conditions, in particular soil moisture and soil and air temperature, interact with both crop seedling and slug emergence during the early autumn season. Late, or inadequate autumn rainfall in western Oregon occasionally causes the timing of emergence of newly established annual ryegrass see...

  8. Cerebellar Disease in an Adult Cow

    PubMed Central

    Oz, H. H.; Nicholson, S. S.; Al-Bagdadi, F. K.; Zeman, D. H.

    1986-01-01

    This is the report of clinical signs and lesions of a cerebellar disorder in an adult four year old Limousin cow grazing perennial ryegrass (Lolium perenne). The most striking histopathological lesion was a marked paucity of Purkinje cells throughout the cerebellum. ImagesFigure 1.Figure 2. PMID:17422607

  9. MINERAL CHARACTERIZATION OF TEMPERATE GRASSES FROM A HIGH RAINFALL ENVIRONMENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Straw produced as a co-product of perennial ryegrass (Lolium perenne L.), orchardgrass (Dactylis glomerata L.), tall fescue [Schedonorus phoenix (Scop.) Holub] (formerly Festuca arundinacea Schreb.), and Kentucky bluegrass (Poa pratensis L.) seed production in the high rainfall area of western Orego...

  10. OCCURRENCE OF A TILLETIA SP. IN CHEWINGS FESCUE FIELDS IN OREGON

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An undescribed species of Tilletia with reticulate teliospores was recently reported in a shipment of fine fescue seed from the U.S. to China (1). This fungus has also been detected in perennial ryegrass (Lolium perenne) seed from Australia, although naturally infected plants have not yet been obser...

  11. Comparative trends in forage nutritional quality across the growing season in thirteen grasses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Based on recent climate change models, landscapes are likely going to get drier and hotter; thus reducing the available water to support herbage production in species heavily dependent on water for persistence and production such as perennial ryegrass (Lolium perenne L.), orchardgrass (Dactylis glom...

  12. Uptake and transformation of soil [14C]-trinitrotoluene by cool-season grasses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study investigated the fate and uptake of [14C]-TNT from soil into orchardgrass (Dactylis glomerata), perennial ryegrass (Lolium perenne) and tall fescue (Festuca arundinacea) over a one year period in a greenhouse-controlled environment. Pots (n=4 for each grass, containing 10 mg cold TNT/kg s...

  13. Performance of low-input turfgrass species as affected by mowing and nitrogen fertilization in Minnesota

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In Minnesota, most lawns and higher cut turfgrass areas consist primarily of species such as Kentucky bluegrass (Poa pratensis L.) and perennial ryegrass (Lolium perenne L.) that require significant management inputs such as frequent mowing and nitrogen fertility. Several studies have shown that oth...

  14. Selection for low or high primary dormancy in Lolium rigidum Gaud seeds results in constitutive differences in stress protein expression and peroxidase activity

    PubMed Central

    Goggin, Danica E.; Powles, Stephen B.; Steadman, Kathryn J.

    2011-01-01

    Seed dormancy in wild Lolium rigidum Gaud (annual ryegrass) populations is highly variable and not well characterized at the biochemical level. To identify some of the determinants of dormancy level in these seeds, the proteomes of subpopulations selected for low and high levels of primary dormancy were compared by two-dimensional polyacrylamide gel electrophoresis of extracts from mature, dry seeds. High-dormancy seeds showed higher expression of small heat shock proteins, enolase, and glyoxalase I than the low-dormancy seeds. The functional relevance of these differences in protein expression was confirmed by the fact that high-dormancy seeds were more tolerant to high temperatures imposed at imbibition and had consistently higher glyoxalase I activity over 0–42 d dark stratification. Higher expression of a putative glutathione peroxidase in low-dormancy seeds was not accompanied by higher activity, but these seeds had a slightly more oxidized glutathione pool and higher total peroxidase activity. Overall, these biochemical and physiological differences suggest that L. rigidum seeds selected for low dormancy are more prepared for rapid germination via peroxidase-mediated cell wall weakening, whilst seeds selected for high dormancy are constitutively prepared to survive environmental stresses, even in the absence of stress during seed development. PMID:20974739

  15. Water deficit and induction of summer dormancy in perennial Mediterranean grasses

    PubMed Central

    Volaire, Florence; Seddaiu, Giovanna; Ledda, Luigi; Lelievre, François

    2009-01-01

    Background and Aims Summer dormancy is a trait conferring superior drought survival in Mediterranean perennial grasses. As the respective roles of environmental factors and water deficit on induction of summer dormancy are unclear, the effect of intense drought were tested under contrasting day lengths in a range of forage and native grasses. Methods Plants of Poa bulbosa, Dactylis glomerata ‘Kasbah’ and Lolium arundinaceum ‘Flecha’ were grown in pots (a) from winter to summer in a glasshouse and subjected to either an early or a late-spring drought period followed by a summer water deficit and (b) in controlled conditions, with long days (LD, 16 h) or short days (SD, 9 h) and either full irrigation or water deficit followed by rehydration. Leaf elongation, senescence of aerial tissues and dehydration of basal tissues were measured to assess dormancy. Endogenous abscisic acid (ABA) in basal tissues was determined by monoclonal immunoassay analysis. Key Results Even under irrigation, cessation of leaf elongation, senescence of lamina and relative dehydration of basal tissues were triggered only by a day length longer than 13 h 30 min (late spring and LD) in plants of Poa bulbosa and Dactylis glomerata ‘Kasbah’ which exhibit complete dormancy. Plants of Lolium arundinaceum ‘Flecha’ maintained leaf growth under irrigation irrespective of the day length since its dormancy is incomplete. ABA concentrations were not higher during late-spring drought than early, and could not be associated with spring dormancy induction. In summer, ABA concentration in bulbs of the desiccation-tolerant Poa were greater than in basal tissues of other species. Conclusions The results of both experiments tend to invalidate the hypothesis that water deficit has a role in early summer-dormancy induction in the range of tested grasses. However, a late-spring drought tends to increase plant senescence and ABA accumulation in basal tissues of forage grasses which could enhance

  16. A simulation model for epidemics of stem rust in ryegrass seed crops.

    PubMed

    Pfender, W F; Upper, D

    2015-01-01

    A simulation model (STEMRUST_G, named for stem rust of grasses) was created for stem rust (caused by Puccinia graminis subsp. graminicola) in perennial ryegrass grown to maturity as a seed crop. The model has a daily time step and is driven by weather data and an initial input of disease severity from field observation. Key aspects of plant growth are modeled. Disease severity is modeled as rust population growth, where individuals are pathogen colonies (pustules) grouped in cohorts defined by date of initiation and plant part infected. Infections due to either aerial spread or within-plant contact spread are modeled. Pathogen cohorts progress through life stages that are modeled as disease cycle components (colony establishment, latent period, infectious period, and sporulation) affected by daily weather variables, plant growth, and fungicide application. Fungicide effects on disease cycle components are modeled for two commonly used active ingredients, applied preinfection or postinfection. Previously validated submodels for certain disease cycle components formed the framework for integrating additional processes, and the complete model was calibrated with field data from 10 stem rust epidemics. Discrepancies between modeled outcomes and the calibration data (log10[modeled]-log10[observed]) had a mean near zero but considerable variance, with 1 standard deviation=0.5 log10 units (3.2-fold). It appears that a large proportion of the modeling error variance may be due to variability in field observations of disease severity. An action threshold for fungicide application was derived empirically, using a constructed weather input file favorable for disease development. The action threshold is a negative threshold, representing a level of disease (latent plus visible) below which damaging levels of disease are unable to develop before the yield-critical crop stage. The model is in the public domain and available on the Internet. PMID:25098493

  17. Seed Germination Differences Between Glyphosate-Resistant and -Susceptible Italian Ryegrass Populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Italian ryegrass tolerant to glyphosate is becoming a major weed problem in glyphosate-resistant crops. The effects of temperature, light, pH, salt and osmotic stress, shikimic acid, and planting depth on germination of glyphosate-tolerant (T) and susceptible (S) Italian ryegrass populations were st...

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

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

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

  19. Identification of quantitative trait loci for seed trait and floral morphology in a field-grown Lolium perenne x Lolium multiflorum mapping population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lolium multiflorum Lam. and L. perenne L. differ in the requirements for initiation of flowering, and in other morphological traits. Generally, L. multiflorum spikes are larger than L. perenne spikes, and have more spikelets, more florets per spikelet, larger seeds, and awns. The greater number of s...

  20. Herbicidal activity of Brassicaceae seed meal on wild oat (Avena fatua), Italian ryegrass (Lolium multiflorum Lam.), redroot pigweed (Amaranthus retroflexus L.) and prickly lettuce (Lactuca serriola)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is an on-going need for the development of sustainable methods of weed control in crop production systems. Studies were conducted to evaluate the efficacy of different Brassicaceae seed meals and application rates on the emergence of several weed species including wild oat, Italian rye grass, ...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Main challenge of phytoremediation of co-contaminated soils is developing strategies for efficient and simultaneous removal of multiple pollutants. A pot experiment was conducted to investigate the potential for phytoextraction of heavy metals and rhizoremediaiton of polycyclic aromatic hydrocarbons...

  2. [Effects of dissolved organic matter on copper absorption by ryegrass].

    PubMed

    Tang, Chao; Wang, Bin; Liu, Man-Qiang; Hu, Feng; Li, Hui-Xin; Jiao, Jia-Guo

    2012-08-01

    In this study, dissolved organic matter (DOM) was extracted from earthworm casts and from the cattle manure with which the earthworms were fed, and a water culture experiment was conducted to study the effects of the DOM on the copper (Cu2+) absorption by ryegrass in the presence of different concentration Cu2+ (0, 5 and 10 mg x L(-1)). With the increasing concentration of Cu2+ in the medium, there was a gradual decrease in the dry mass of ryegrass shoots and roots and in the root length, surface area, volume, and tip number. In the presence of medium Cu2+, DOM increased the biomass of shoots and roots and the root length, surface area, volume, and tip number significantly. DOM reduced the Cu2+ concentration in roots, promoted the Cu2+ translocation from roots to shoots, and significantly increased the Cu2+ accumulation in shoots. The DOM from earthworm casts had better effects than that from cattle manure, and high concentration DOM had better effects than low concentration DOM. PMID:23189712

  3. Managing Perennial Monocultures for Ecosystem Services

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Miscanthus (Miscanthus x giganteus) and switchgrass (Panicum virgatum L.) are perennial grasses that can provide both renewable energy and ecosystem services, but the extent to which they do depends strongly on crop management. Nutrient use efficiency and wildlife habitat provision are influenced pr...

  4. Increased carrying capacity with perennial forage kochia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carrying capacity can be increased on grass-dominated rangeland pastures by including perennial forage kochia (Kochia prostrata) as one of the plant components. The objectives of the study reported here were to compare the differences of traditional winter pastures versus pastures with forage kochi...

  5. Soil Carbon Fractionation under Perennial Forage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop management practices can improve soil quality. Forage type and N-sources might also affect soil organic matter, especially soil carbon fractionation. The objective of this study is to evaluate the impact of legume inter-planting and compost application on soil C pools under a perennial grass mi...

  6. Remodeling of Leaf Cellular Glycerolipid Composition under Drought and Re-hydration Conditions in Grasses from the Lolium-Festuca Complex

    PubMed Central

    Perlikowski, Dawid; Kierszniowska, Sylwia; Sawikowska, Aneta; Krajewski, Paweł; Rapacz, Marcin; Eckhardt, Änne; Kosmala, Arkadiusz

    2016-01-01

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

  7. Identification of extracellular siderophores and a related peptide from the endophytic fungus Epichloë festucae in culture and endophyte-infected Lolium perenne

    PubMed Central

    Koulman, Albert; Lee, T. Verne; Fraser, Karl; Johnson, Linda; Arcus, Vickery; Lott, J. Shaun; Rasmussen, Susanne; Lane, Geoffrey

    2012-01-01

    A number of genes encoding non-ribosomal peptide synthetases (NRPSs) have been identified in fungi of Epichloë/Neotyphodium species, endophytes of Pooid grasses, including sidN, putatively encoding a ferrichrome siderophore-synthesizing NRPS. Targeted gene replacement and complementation of sidN in Epichloë festucae has established that extracellular siderophore epichloënin A is the major product of the SidN enzyme complex (Johnson et al., 2007a). We report here high resolution mass spectrometric fragmentation experiments and NMR analysis of an isolated fraction establishing that epichloënin A is a siderophore of the ferrichrome family, comprising a cyclic sequence of four glycines, a glutamine and three Nδ-trans-anhydromevalonyl–Nδ-hydroxyornithine (AMHO) moieties. Epichloënin A is unusual among ferrichrome siderophores in comprising an octapeptide rather than hexapeptide sequence, and in incorporating a glutamine residue. During this investigation we have established that desferrichrome siderophores with pendant trans-AMHO groups can be distinguished from those with pendant cis-AMHO groups by the characteristic neutral loss of an hydroxyornithine moiety in the MS/MS spectrum. A minor component, epichloënin B, has been characterized as the triglycine variant by mass spectrometry. A peptide characterized by mass spectrometry as the putative deoxygenation product, epichloëamide has been detected together with ferriepichloënin A in guttation fluid from ryegrass (Lolium perenne) plants infected with wild-type E. festucae, but not in plants infected with the ΔsidN mutant strain, and also detected at trace levels in wild-type E. festucae fungal culture. PMID:22196939

  8. The photosynthetic acclimation of Lolium perenne in response to three years growth in a free-air CO{sub 2} enrichment (FACE) system

    SciTech Connect

    Hymus, G.J. |

    1996-08-01

    Pure stands of Ryegrass were in their third year of growth in the field, exposed to either ambient (355 {mu}mol mol{sup -1}), or elevated (600 {mu}mol mol{sup -1}) atmospheric CO{sub 2} concentration. A Free-Air CO{sub 2} Enrichment (FACE) system was used to maintain the elevated CO{sub 2} concentration whilst limiting experimental constraints on the field conditions. The theoretically predicted increase in the net rates of CO{sub 2} uptake per unit leaf area (A {mu}mol mol{sup -1}) as a consequence, primarily, of the suppression of photorespiration by CO{sub 2} a competitive inhibitor of RubP oxygenation by Rubisco, was observed for the Lolium perenne studied. Also observed was a general decline in leaf evapotranspiration (E) consistent with observations of increased water use efficiency of crops grown in elevated CO{sub 2}. Enhancement of leaf A in the FACE grown L. perenne ranged from 26.5 1 % to 44.95% over the course of a diurnal set of measurements. Whilst reductions in leaf E reached a maximum of 16.61% over the same diurnal course of-measurements. The increase in A was reconciled with an absence of the commonly observed decline in V{sub c}{sub max} as a measure of the maximum in vivo carboxylation capacity of the primary carboxylasing enzyme Rubisco and J{sub max} a measure of the maximum rate of electron transport. The manipulation of the source sink balance of the crop, stage of canopy regrowth or height in the canopy had no effect on the observation of a lack of response. The findings of this study will be interpreted with respect to the long term implications of C{sub 3} crops being able to adapt physiologically to maximize the potential benefits conferred by growth in elevated CO{sub 2}.

  9. Remodeling of Leaf Cellular Glycerolipid Composition under Drought and Re-hydration Conditions in Grasses from the Lolium-Festuca Complex.

    PubMed

    Perlikowski, Dawid; Kierszniowska, Sylwia; Sawikowska, Aneta; Krajewski, Paweł; Rapacz, Marcin; Eckhardt, Änne; Kosmala, Arkadiusz

    2016-01-01

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

  10. Herbaceous Perennials: Placement, benefits and incorporation challenges in diversified landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Herbaceous perennial feedstocks will fill numerous and critical roles in the bioenergy landscape. Our objective is to present the benefits and challenges of growing herbaceous perennials and provide regionally-specific scenarios for their use at the landscape scale. The primary herbaceous perennial ...

  11. Perennial nonallergic rhinitis: a retrospective review.

    PubMed

    Enberg, R N

    1989-12-01

    Forty-six of 152 consecutive adult rhinitis patients had perennial nonallergic rhinitis (PNR). Eighty-five percent of those with PNR presented with nasal congestion, whereas 15% presented with rhinorrhea. Their mean age was 40.5 years (range = 21-77), and 74% were female. Patients with perennial nonallergic rhinitis in this series were characterized by ocular pruritus or burning, 28%; frontal headache, 22%; symptoms consistent with asthma, 33%; an unremarkable nasal mucosa, 96%; the absence of nasal polyps, 100%; nasal eosinophilia (greater than or equal to 5%), 10%; nasal neutrophilia (greater than or equal to 25%), 22%; numerous nasal bacteria, 12%; sinusitis, 6%; and a geometric mean IgE of 26.4 U/mL. This experience suggests that PNR is a common problem in a general allergy practice. Nasal obstruction, usually more difficult to treat than rhinorrhea, is the dominant symptom. Unexpected findings were frequent conjunctivitis and nasal neutrophilia. PMID:2480728

  12. Influence of different acid and alkaline cleaning agents on the effects of irrigation of synthetic dairy factory effluent on soil quality, ryegrass growth and nutrient uptake.

    PubMed

    Liu, Y-Y; Haynes, R J

    2013-01-01

    The aim of this study was to examine the effects of replacement of phosphoric acid with nitric or acetic acid, and replacement of NaOH with KOH, as cleaning agents in dairy factories, on the effects that irrigation of dairy factory effluent (DFE) has on the soil-plant system. A 16-week greenhouse study was carried out in which the effects of addition of synthetic dairy factory effluent containing (a) milk residues alone or milk residues plus (b) H(3)PO(4)/NaOH, (c) H(3)PO(4)/HNO(3)/NaOH or (d) CH(3)COOH/KOH, on soil's chemical, physical and microbial properties and perennial ryegrass growth and nutrient uptake were investigated. The cumulative effect of DFE addition was to increase exchangeable Na, K, Ca, Mg, exchangeable sodium percentage, microbial biomass C and N and basal respiration in the soil. Dry matter yields of ryegrass were increased by additions of DFE other than that containing CH(3)COOH. Plant uptake of P, Ca and Mg was in the same order as their inputs in DFE but for Na; inputs were an order of magnitude greater than plant uptake. Replacement of NaOH by KOH resulted in increased accumulation of exchangeable K. The effects of added NaOH and KOH on promoting breakdown of soil aggregates during wet sieving (and formation of a < 0.25 mm size class) were similar. Replacement of H(2)PO(4) by HNO(3) is a viable but CH(3)COOH appears to have detrimental effects on plant growth. Replacement of NaOH by KOH lowers the likelihood of phytotoxic effects of Na, but K and Na have similar effects on disaggregation. PMID:22707204

  13. Evaluation of reference genes for quantitative RT-PCR in Lolium temulentum under abiotic stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lolium temulentum is a valuable model grass species for the study of stress in forage and turf grasses. Gene expression analysis by quantitative real time RT-PCR relies on the use of proper internal standards. The aim of this study was to identify and evaluate reference genes for use in real-time q...

  14. Transcriptome response in different tissues of Lolium arundinaceum to the fungal endophyte Epichloe coenophiala

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tall fescue (Lolium arundinaceum) plants symbiotic with the endophytic fungus, Epichloe coenophiala , (E+), have been shown to have better survivability and persistence than plants lacking the endophyte (E-). To understand more about the grass-endophyte interactions and how endophyte affects the ho...

  15. Transcriptome response of Lolium arundinaceum to the fungal endophyte Epichloe coenophiala

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tall fescue (Lolium arundinaceum) is one of the principal cool-season species used as a forage and turf within the USA. A number of benefits associated with the persistence of tall fescue have been attributed to the presence of its seed-transmissible symbiont, the fungal endophyte Epichloë coenophi...

  16. Abiotic stresses activate a MAPkinase in the model grass species Lolium temulentum L.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Forage and turf grasses are utilized in diverse environments which exposes them to a variety of abiotic stresses, however very little is known concerning the perception or molecular responses to these various stresses. In the model grass species Lolium temulentum (Lt), a 46 kDa mitogen-activated pro...

  17. Lolium latent virus (Alphaflexiviridae) coat proteins: expression and functions in infected plant tissue

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Lolium latent virus (LoLV, Lolavirus, Alphaflexiviridae) viral genome is encapsidated by two carboxy-coterminal coat protein (CP) variants (about 28 and 33 kDa), in equimolar proportion. The CP ORF contains two 5'-proximal AUGs, encoding Met 1 and Met 49, respectively promoting translation of th...

  18. Productivity and carbon footprint of perennial grass-forage legume intercropping strategies with high or low nitrogen fertilizer input.

    PubMed

    Hauggaard-Nielsen, Henrik; Lachouani, Petra; Knudsen, Marie Trydeman; Ambus, Per; Boelt, Birte; Gislum, René

    2016-01-15

    A three-season field experiment was established and repeated twice with spring barley used as cover crop for different perennial grass-legume intercrops followed by a full year pasture cropping and winter wheat after sward incorporation. Two fertilization regimes were applied with plots fertilized with either a high or a low rate of mineral nitrogen (N) fertilizer. Life cycle assessment (LCA) was used to evaluate the carbon footprint (global warming potential) of the grassland management including measured nitrous oxide (N2O) emissions after sward incorporation. Without applying any mineral N fertilizer, the forage legume pure stand, especially red clover, was able to produce about 15 t above ground dry matter ha(-1) year(-1) saving around 325 kg mineral Nfertilizer ha(-1) compared to the cocksfoot and tall fescue grass treatments. The pure stand ryegrass yielded around 3t DM more than red clover in the high fertilizer treatment. Nitrous oxide emissions were highest in the treatments containing legumes. The LCA showed that the low input N systems had markedly lower carbon footprint values than crops from the high N input system with the pure stand legumes without N fertilization having the lowest carbon footprint. Thus, a reduction in N fertilizer application rates in the low input systems offsets increased N2O emissions after forage legume treatments compared to grass plots due to the N fertilizer production-related emissions. When including the subsequent wheat yield in the total aboveground production across the three-season rotation, the pure stand red clover without N application and pure stand ryegrass treatments with the highest N input equalled. The present study illustrate how leguminous biological nitrogen fixation (BNF) represents an important low impact renewable N source without reducing crop yields and thereby farmers earnings. PMID:26479907

  19. Evaluation of the Ryegrass Stem Rust Model STEMRUST_G and Its Implementation as a Decision Aid.

    PubMed

    Pfender, W F; Coop, L B; Seguin, S G; Mellbye, M E; Gingrich, G A; Silberstein, T B

    2015-01-01

    STEMRUST_G, a simulation model for epidemics of stem rust in perennial ryegrass grown to maturity as a seed crop, was validated for use as a heuristic tool and as a decision aid for disease management with fungicides. Multistage validation had been used in model creation by incorporating previously validated submodels for infection, latent period duration, sporulation, fungicide effects, and plant growth. Validation of the complete model was by comparison of model output with observed disease severities in 35 epidemics at nine location-years in the Pacific Northwest of the United States. We judge the model acceptable for its purposes, based on several tests. Graphs of modeled disease progress were generally congruent with plotted disease severity observations. There was negligible average bias in the 570 modeled-versus-observed comparisons across all data, although there was large variance in size of the deviances. Modeled severities were accurate in >80% of the comparisons, where accuracy is defined as the modeled value being within twice the 95% confidence interval of the observed value, within ±1 day of the observation date. An interactive website was created to produce disease estimates by running STEMRUST_G with user-supplied disease scouting information and automated daily weather data inputs from field sites. The model and decision aid supplement disease managers' information by estimating the level of latent (invisible) and expressed disease since the last scouting observation, given season-long weather conditions up to the present, and it estimates effects of fungicides on epidemic development. In additional large-plot experiments conducted in grower fields, the decision aid produced disease management outcomes (management cost and seed yield) as good as or better than the growers' standard practice. In future, STEMRUST_G could be modified to create similar models and decision aids for stem rust of wheat and barley, after additional experiments to

  20. Summer Dormancy in Perennial Temperate Grasses

    PubMed Central

    VOLAIRE, FLORENCE; NORTON, MARK

    2006-01-01

    • Background and Aims Dormancy has been extensively studied in plants which experience severe winter conditions but much less so in perennial herbaceous plants that must survive summer drought. This paper reviews the current knowledge on summer dormancy in both native and cultivated perennial temperate grasses originating from the Mediterranean Basin, and presents a unified terminology to describe this trait. • Scope Under severe drought, it is difficult to separate the responses by which plants avoid and tolerate dehydration from those associated with the expression of summer dormancy. Consequently, this type of endogenous (endo-) dormancy can be tested only in plants that are not subjected to moisture deficit. Summer dormancy can be defined by four criteria, one of which is considered optional: (1) reduction or cessation of leaf production and expansion; (2) senescence of mature foliage; (3) dehydration of surviving organs; and (4, optional) formation of resting organs. The proposed terminology recognizes two levels of summer dormancy: (a) complete dormancy, when cessation of growth is associated with full senescence of foliage and induced dehydration of leaf bases; and (b) incomplete dormancy, when leaf growth is partially inhibited and is associated with moderate levels of foliage senescence. Summer dormancy is expressed under increasing photoperiod and temperature. It is under hormonal control and usually associated with flowering and a reduction in metabolic activity in meristematic tissues. Dehydration tolerance and dormancy are independent phenomena and differ from the adaptations of resurrection plants. • Conclusions Summer dormancy has been correlated with superior survival after severe and repeated summer drought in a large range of perennial grasses. In the face of increasing aridity, this trait could be used in the development of cultivars that are able to meet agronomic and environmental goals. It is therefore important to have a better

  1. Photoperiodic growth control in perennial trees

    PubMed Central

    Azeez, Abdul; Sane, Aniruddha P

    2015-01-01

    Plants have to cope with changing seasons and adverse environmental conditions. Being sessile, plants have developed elaborate mechanisms for their survival that allow them to sense and adapt to the environment and reproduce successfully. A major adaptive trait for the survival of trees of temperate and boreal forests is the induction of growth cessation in anticipation of winters. In the last few years enormous progress has been made to elucidate the molecular mechanisms underlying SDs induced growth cessation in model perennial tree hybrid aspen (Populus tremula × P. tremuloides). In this review we discuss the molecular mechanism underlying photoperiodic control of growth cessation and adaptive responses. PMID:26340077

  2. Denitrification and N2O emissions in annual croplands, perennial grass buffers, and restored perennial grasslands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inclusion of perennial vegetation filter strips (PFS) in the toeslope of annual cropland watersheds can decrease nitrate (NO3) losses to ground and surface waters. Although PFS are similar to riparian buffers, PFS are a relatively new conservation tool and the processes responsible for NO3 removal f...

  3. Association study between the gibberellic acid insensitive gene and leaf length in a Lolium perenne L. synthetic variety

    PubMed Central

    2011-01-01

    Background Association studies are of great interest to identify genes explaining trait variation since they deal with more than just a few alleles like classical QTL analyses. They are usually performed using collections representing a wide range of variability but which could present a genetic substructure. The aim of this paper is to demonstrate that association studies can be performed using synthetic varieties obtained after several panmictic generations. This demonstration is based on an example of association between the gibberellic acid insensitive gene (GAI) polymorphism and leaf length polymorphism in 'Herbie', a synthetic variety of perennial ryegrass. Methods Leaf growth parameters, consisted of leaf length, maximum leaf elongation rate (LERmax) and leaf elongation duration (LED), were evaluated in spring and autumn on 216 plants of Herbie with three replicates. For each plant, a sequence of 370 bp in GAI was analysed for polymorphism. Results Genetic effect was highly significant for all traits. Broad sense heritabilities were higher for leaf length and LERmax with about 0.7 in each period and 0.5 considering both periods than for LED with about 0.4 in each period and 0.3 considering both periods. GAI was highly polymorphic with an average of 12 bp between two consecutive SNPs and 39 haplotypes in which 9 were more frequent. Linkage disequilibrium declined rapidly with distance with r 2 values lower than 0.2 beyond 150 bp. Sequence polymorphism of GAI explained 8-14% of leaf growth parameter variation. A single SNP explained 4% of the phenotypic variance of leaf length in both periods which represents a difference of 33 mm on an average of 300 mm. Conclusions Synthetic varieties in which linkage disequilibrium declines rapidly with distance are suitable for association studies using the "candidate gene" approach. GAI polymorphism was found to be associated with leaf length polymorphism which was more correlated to LERmax than to LED in Herbie. It is a

  4. What makes a perennial a perennial? A meta-analysis of allocation patterns and functional traits in congeneric annual and perennial plant

    NASA Astrophysics Data System (ADS)

    Vico, Giulia; Manzoni, Stefano; Weih, Martin

    2014-05-01

    Currently, a large fraction of food, fiber, and feed is provided by annual crops - in particular annual grains. A shift from annual to perennial crops has been advocated to move towards a more sustainable agriculture. While providing lower yields than annuals, perennial crops are often assumed to reduce soil erosion, promote soil health, and be able to achieve higher water and nitrogen use efficiency, primarily through higher allocation below ground. Nevertheless, quantifications of these benefits are still scarce and often inconclusive, as well as mostly limited to first-year perennials. Here we consider congeneric annual and perennial species pairs, for which measured productivity, resource allocation, and resource use efficiency are available in the literature, in search for a signature of life-history (i.e., annuality vs. perenniality) on plant allocation, traits, and agronomic performances. A new database of allocation strategies and functional traits of these congeneric species is developed, covering more than 25 genera of agronomical and ecological relevance, including wild and domesticated species, as well as new hybrids, grown under a variety of conditions. Some general patterns emerge. Perennials have lower biomass allocation to reproductive structures (as expected), and generally higher root-to-shoot biomass ratio, potentially promoting soil C accumulation. Patterns in nitrogen tissue concentration and resource use efficiencies are less clear, due to the limited available data. Our analyses highlight a paucity of comprehensive studies, hampering our understanding of the long-term implications of a shift to perennial crops for ecosystem hydrologic and biogeochemical cycles.

  5. Reduction of high soil test phosphorus by bermudagrass and ryegrass-bermudagrass following the cessation of broiler litter applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus accumulation occurs in soils that are over fertilized with manure. Previous studies indicate overseeding bermudagrass with annual ryegrass can remove more nutrients from manure-treated soils than bermudagrass winter-fallow system. This study determined if harvesting ryegrass hay in additi...

  6. A feasibility study of perennial/annual plant species to restore soils contaminated with heavy metals

    NASA Astrophysics Data System (ADS)

    Zacarías, Montserrat; Beltrán, Margarita; Gilberto Torres, Luis; González, Abelardo

    A feasibility study was carried out to evaluate the application of perennial/annual plant species in a phytoextraction process of a previously washed industrial urban soil contaminated by nickel, arsenic and cupper. The plant species selected for this study were Ipomea (Ipomea variada); grass (Poa pratensis); grass mixture (Festuca rubra, Cynodon dactylon, Lolium multiforum, Pennisetum sp.); Monks Cress (Tropaeolum majus); ficus (Ficus benajamina) and fern (Pteris cretica). Soil was characterized and it presented the following heavy metals concentrations (dry weight): 80 mg of Ni/kg, 456-656 mg of As/kg and 1684-3166 mg of Cu/kg. Germination and survival in contaminated soil tests were conducted, from these, P. pratensis was discarded and the rest of plant species tested were used for the phytoextraction selection test. After 4 months of growth, biomass production was determined, and content of Ni, As and Cu was analyzed in plant’s tissue. Metal biological absorption coefficient (BAC), bio-concentration factor (BCF) and translocation factor (TF), were calculated. Regarding to biomass generation it was observed, in every case, an inhibition of the plant growth compared with blanks sown in a non contaminated soil; inhibition ranged from 22.5% for the Monk cress to 98% for Ipomea. Even though the later presented high BAC, BCF and TF, its growth was severely inhibited, and therefore, due its low biomass generation, it is not recommended for phytoextraction under conditions for this study. Heavy metals concentrations in plant’s tissue (dry weight) were as high as 866 mg Cu/kg and 602 mg As/kg for grass mixture; and 825 mg As/kg was observed for Monks cress. Grass mixture and monks cress had high BAC, BCF and TF, also they had high metal concentrations in its plants tissues and the lowest growth inhibition rates; hence the application in phytoextraction processes of these plants is advisable.

  7. Production of tremorgenic toxins by Penicillium janthinellum Biourge: a possible aetiological factor in ryegrass staggers.

    PubMed

    Lanigan, G W; Payne, A L; Cockrum, P A

    1979-02-01

    Topsoil, herbage and faeces collected during an outbreak of ryegrass staggers in sheep were examined for tremorgenic penicillia. No such fungi were recovered from the plant material, but they were found among the predominant fungi in the soil and faecal samples. The commonest species of Penicillium, and almost the only tremorgenic species encountered, was Penicillium janthinellum Biourge. When fed to sheep, the mycelium of this fungus evoked a number of the clinical signs seen in field cases of ryegrass staggers. Two tremorgenic toxins were isolated from the mycelial felts and available evidence indicates that they are verruculogen and fumitremorgin A. P. janthinellum also produced these tremorgens when cultured in moist, autoclaved soil, but not in unheated soil. The results obtained from this study are in accord with the hypothesis that ryegrass staggers is caused by tremorgenic mycotoxins. PMID:475667

  8. Closing the Carbon Budget in Perennial Biofuel Crops

    NASA Astrophysics Data System (ADS)

    Kantola, I. B.; Anderson-Teixeira, K. J.; Bernacchi, C.; Hudiburg, T. W.; Masters, M. D.; DeLucia, E. H.

    2013-12-01

    At present, some 40% of corn grown in the United States, accounting for more than 26 million acres of farmland, is processed for bioethanol. Interest has arisen in converting biofuel production from corn grain ethanol to cellulosic ethanol, derived primarily from cellulose from dedicated energy crops. As many cellulosic biofuel feedstocks are perennial grasses, conversion from annual corn cropping to perennials represents a substantial change in farming practices with the potential to alter the plant-soil relationship in the Midwestern United States. Elimination of annual tillage preserves soils structure, conserving soil carbon and maintaining plant root systems. Five years of perennial grass establishment in former agricultural land in Illinois has shown a significant change in soil carbon pools and fluxes. Atmospheric carbon exchange monitoring combined with vegetation and soil sampling and respiration measurements confirm that in the first 3 years (establishment phase), perennial giant grasses Miscanthus x giganteus and Panicum virgatum rapidly increased belowground carbon allocation >400% and belowground biomass 400-750% compared to corn. Following establishment, perennial grasses maintained below- and aboveground annual biomass production, out-performing corn in both average and drought conditions. Here we offer a quantitative comparison of the carbon allocation pathways of corn and perennial biofuel crops in Midwestern landscapes, demonstrating the carbon benefits of perennial cropping through increased C allocation to root and rhizome structures. Long rotation periods in perennial grasses combined with annual carbon inputs to the soil system are expected to convert these agricultural soils from atmospheric carbon sources to carbon sinks.

  9. From forest to field: Perennial fruit crop domestication

    Technology Transfer Automated Retrieval System (TEKTRAN)

    • Premise of the study. Understanding of plant domestication and evolution are enhanced by archaeological and genetic analyses of seed-propagated annual crops. Domestication of perennial plants may reveal how genes and genomes evolve in long-lived species and how perennial plants respond to selec...

  10. ECOLOGY AND MANAGEMENT OF PERENNIAL PEPPERWEED [Lepidium latifolium L.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Perennial pepperweed, also called tall whitetop and often confused with whitetop (Cardaria draba), is a rhizomatous perennial weed threatening riparian areas, irrigation ditches, and floodplain meadows in Montana. This weed in the mustard family (Brassicaceae) spreads by creeping roots and rhizomes...