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The main objective of this research was to evaluate the quality indices of green mass, hay, silage and straw from the local ecotype of tall oatgrass, Arrhenatherum elatius, grown in monoculture in the experimental plot of NBGI, Chisinau, Republic of Moldova. The results revealed that the harvested green mass contained 25.0-29.8% dry matter. The dry matter of the whole plant contained 80 g/kg CP6yy, 382 g/kg CF, 83 g/kg ash, 411 g/kg ADF, 710 g/kg NDF, 38 g/kg ADL,118 g/kg TSS, 373 g/kg Cel, 299 g/kg HC, with nutritive and energy value 58.2% DMD, 51.3% DOM, 9.29 MJ/kg ME and 5.31 MJ/kg NEl. The biochemical composition, nutritive and energy value of tall oatgrass hay: 77 g/kg CP, 414 g/kg CF, 80 g/kg ash, 436 g/kg ADF, 740 g/kg NDF, 40 g/kg ADL, 98 g/kg TSS, 396 g/kg Cel and 304 g/kg HC, 9.00 MJ/kg ME and 5.02 MJ/kg NEl. The tall oatgrass fermented fodder- silage is characterized by pH = 4.26, 5.9 g/kg acetic acid, 18.3 g/kg lactic acid and free of butyric acid, 88 g/kg CP, 405 g/kg CF, 100 g/kg ash, 420 g/kg ADF, 724 g/kg NDF, 26 g/kg ADL, 74 g/kg TSS, 394 g/kg Cel, 304 g/kg HC, with nutritive and energy value 56.5% DMD, 9.19 MJ/kg ME, 5.21 MJ/kg NEl. The tall oatgrass straw contained 50 g/kg CP, 51 g/kg ADL, 85 g/kg TSS, 405 g/kg Cel, 286 g/kg HC. The tall oatgrass substrates used for anaerobic digestion have optimal amount of lignin and hemicellulose, the estimated biochemical methane potential varied from 341 to 361 l/kg VS. The tall oatgrass straw and hay may be used as feedstock for the production by cellulosic ethanol, the estimated theoretical ethanol yield from cell wall carbohydrates averaged 507-509 L/t. [ABSTRACT FROM AUTHOR]

Global change has dramatic impacts on grassland diversity. However, little is known about how fast species can adapt to diversity loss and how this affects their responses to global change. Here, we performed a common garden experiment testing whether plant responses to global change are influenced by their selection history and the conditioning history of soil at different plant diversity levels. Using seeds of four grass species and soil samples from a 14-year-old biodiversity experiment, we grew the offspring of the plants either in their own soil or in soil of a different community, and exposed them either to drought, increased nitrogen input, or a combination of both. Under nitrogen addition, offspring of plants selected at high diversity produced more biomass than those selected at low diversity, while drought neutralized differences in biomass production. Moreover, under the influence of global change drivers, soil history, and to a lesser extent plant history, had species-specific effects on trait expression. Our results show that plant diversity modulates plant-soil interactions and growth strategies of plants, which in turn affects plant eco-evolutionary pathways. How this change affects species' response to global change and whether this can cause a feedback loop should be investigated in more detail in future studies.

Copyright of Journal of Agriculture & Nature / Kahramanmaraş Sütçü İmam Üniversitesi Tarım & Doğa Dergisi is the property of Kahramanmaras Sutcu Imam Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aims: Symbiotic fungi commonly increase plant acquisition of soil nutrients. Because prior work has focused on root fungi, we examined how leaf endophytes (Epichloë) influenced plant responses to fertilization and altered plant traits that may cascade to food webs and ecosystem processes.Methods: We manipulated endophyte presence/absence in two populations of Trisetum spicatum, a wild relative of oat, under a 2 × 2 addition of soil nitrogen (N) and phosphorus (P) in the greenhouse.Results: Endophyte symbiosis altered how plant biomass responded to soil N and how plant traits responded to soil P. Endophytes boosted the biomass gains from N-fertilization in one population. Plants from a second population had weak benefits of symbiosis, but the endophyte altered plant traits, by increasing specific leaf area under P-fertilization, root diameter under low P, and concentration of the fungal alkaloid AcAP under N fertilization. Endophyte presence suppressed the typically observed increase in root hair density in response to soil P limitation. Under low P, symbiotic plants from both populations had improved forage quality relative to symbiont-free plants, although N-fertilization had a larger effect size on forage quality than did symbiosis. Finally, the two populations differed in production of fungal alkaloids, which generally increased in response to fertilization.Conclusions: Predicting how microbial symbionts mediate plant acquisition of nutrients requires understanding how much their effects vary among plant and endophyte genotypes. Here, the magnitude and direction of leaf symbionts' effects on plant yield and traits varied between populations and with soil nutrient availability. [ABSTRACT FROM AUTHOR]

Aims Studies along environmental gradients have shown that intraspecific trait variation (ITV) may contribute considerably to community-level trait variation. However, we lack knowledge about how the extent of ITV varies on a local scale and whether a varying extent of ITV is related to differences in local environmental site and plant community characteristics. Methods We investigated plant height, specific leaf area (SLA), leaf dry matter content (LDMC) and leaf greenness of three common grass species (Arrhenatherum elatius, Dactylis glomerata, Poa pratensis) in 12 mown grasslands in a local study area around Jena (Thuringia, Germany) across three spatially hierarchical sampling levels: between sites, between subplots within site and within subplots. Important Findings Arrhenatherum elatius and D. glomerata had higher means in plant height and a lower variation in leaf traits than P. pratensis. The major proportions of variation in leaf traits of P. pratensis and D. glomerata were found within subplots, while the traits of A. elatius varied mainly between sites. Trait correlations across the hierarchical sampling levels were highly consistent in A. elatius, but more variable in D. glomerata and P. pratensis. Environmental site and plant community characteristics mostly explained a larger proportion of variation in trait means in A. elatius than in D. glomerata and P. pratensis, while metrics of ITV were generally less predictable. Our results suggest that trait variation in P. pratensis and D. glomerata is more strongly related to within-site conditions (i.e. biotic interactions), while differences in local environmental conditions between sites have a strong impact on trait variation in A. elatius. Since our study was limited to three grass species, further studies with a greater number of species are required to make generalizations about the importance of biotic interactions and environmental conditions as drivers of ITV at local scale. [ABSTRACT FROM AUTHOR]

Grass species can be classified into different functional types based on their growth strategies, and contrasting persistence strategies are observed in different grass species. Excluding seedling recruitments, changes in populations of grasses are basically a trade-off between natality and mortality of tillers. We hypothesised that the persistence pathway of perennial grasses is linked to their growth strategy, regardless whether they are growing as monoculture or as a mixture. Species with contrasting growth strategies (Arrhenatherum elatius L., Dactylis glomerata L., and Festuca arundinacea Schreb.) were cultivated as monocultures and as a mixture and their tiller natality and mortality were evaluated for two years after swards establishment. All pastures maintained their population size during the experimental period, although decreases in tiller densities occurred during the warmer season. Arrhenatherum elatius had the highest tiller mortality and natality whereas the F. arundinacea had the lowest ones. Arrhenatherum elatius had many tillers appearing in all seasons but their tillers were short-lived. Conversely, F. arundinacea and D. glomerata developed numerous tillers during autumn and winter and their tillers survived, on average, almost six and three times longer than those of A. elatius, respectively. There were no differences in tillering dynamics among populations grown in monocultures or in the mixture. Regardless of whether they were cultivated in monocultures or as a mixture, the persistence pathway of perennial grasses is linked with their growth strategies with exploitative species presenting a high tiller turnover throughout the year whereas the persistence of more conservative species is based on a high tiller survival. [ABSTRACT FROM AUTHOR]

Studies associated with regional roughage utilisation in Tibetan sheep have been limited. This study focussed on the mechanism of lipid metabolism and deposition in Tibetan sheep fed local roughage sources. Twenty-four Tibetan sheep weighing 16.1 ± 1.76 kg were randomly assigned to two mixed diets containing the same concentrate mixed with oat grass (OG) or highland barley straw (HBS). The ME and CP of OG diet were 7.16 MJ/kg DM and 5.94%, respectively, while in HBS diet were 7.13 MJ/kg DM and 7.39%. Lipid profiles in the plasma and liver, fatty acid (FA) composition and lipogenetic genes expression in the muscle and adipose tissue were determined. No difference was observed in DMI, total cholesterol, triglyceride, low-density lipoprotein and high-density lipoprotein levels in the plasma and liver of sheep between two groups (p>.05). Plasma leptin and liver non-esterified fatty acid (NEFA) content in HBS group tended to be greater than that in OG group (p < .01). Sheep in HBS group had greater C18:2, C20:4, PUFA and PUFA/SFA ratio in the longissimus dorsi muscle (p < .05) and lower C17:0 (p = .05) and C20:1 (p < .01) in the perirenal adipose fat. Perirenal C18:0, C20:3 and C20:4 contents in HBS group tended to increase (p < .01). HBS stimulated the mRNA expression of SCD, C/EBPγ and SREBF1 in the muscle and FASN in the perirenal adipose fat (p < .01), but inhibited HSL, LPL, C/EBPγ and PPARγ expression in the perirenal adipose fat. These results indicated that replacement of OG by HBS promotes PUFA deposition in the muscle and long-chain FAs in the adipose fat of Tibetan sheep. Lipid deposition-related genes (SCD, FASN, HSL and LPL) and lipid metabolism regulators (C/EBPγ, SREBF1 and PPARγ) are involved in the transcriptional regulation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central European Agriculture is the property of Journal of Central European Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We propose a method for monitoring heavy metal deposition in the vicinity of roads using the leaf surfaces of two expansive grass species which are greatly abundant. A principle of the proposed procedure is to minimize the number of operations in collecting and preparing samples for analysis. The monitored elements are extracted from the leaf surfaces using dilute nitric acid directly in the sample-collection bottle. The ensuing steps, then, are only to filter the extraction solution and the elemental analysis itself. The verification results indicate that the selected grasses Calamagrostis epigejos and Arrhenatherum elatius are well suited to the proposed procedure. Selected heavy metals (Zn, Cu, Pb, Ni, Cr, and Cd) in concentrations appropriate for direct determination using methods of elemental analysis can be extracted from the surface of leaves of these species collected in the vicinity of roads with medium traffic loads. Comparing the two species showed that each had a different relationship between the amounts of deposited heavy metals and distance from the road. This disparity can be explained by specific morphological properties of the two species' leaf surfaces. Due to the abundant occurrence of the two species and the method's general simplicity and ready availability, we regard the proposed approach to constitute a broadly usable and repeatable one for producing reproducible results. [ABSTRACT FROM AUTHOR]

Coastal habitats are rich in biodiversity and provide highly valued ecosystem services. However, they are subject to many environmental drivers that can have severe impacts on these inherently fragile ecosystems. A resurvey approach was used to assess changes in species’ abundances and occupancy on sand dunes and machair in Scotland, UK to assess how this could impact on this set of habitats. These were assessed to see if increasers and decreasers shared common trait values, if trends were similar to other terrestrial habitats and if responses to environmental drivers were modulated by traits. In general, there has been a shift towards taller species with more exploitative growth forms and an increase in indicators of unfavourable habitat condition according to criteria for assessing sites designated for nature protection as part of the EU Natura 2000 network, particularly tall grasses characteristic of nutrient-rich conditions exemplified by Arrhenatherum elatius . Coastal heathlands have been particularly affected by the increase in species such as Betula spp. and Pteridium aquilinum which can dominate and exclude other heathland species. On average, increasing species were both more common nationally and increasing nationally, suggesting increasing homogenisation between sand dunes/machair and other terrestrial habitats. Changes have been faster and more negative in conservation terms in cooler, drier and more polluted sites (mainly on the east coast of Scotland) and also in sites which had seen reductions in grazing. Reinstating grazing could counteract some of the negative impacts of eutrophication, but this could prove problematic to integrate with recreational activities and the largely arable based farming systems adjacent to these sites. [ABSTRACT FROM AUTHOR]

Across Europe, genetic diversity can be expected to decline toward the North because of stochastic and selective effects which may imply diminished phenotypic variation and less potential for future genetic adaptations to environmental change. Understanding such latitudinal patterns can aid provenance selection for breeding or assisted migration approaches. In an experiment simulating different winter temperatures, we assessed quantitative trait variation, genetic diversity, and differentiation for natural populations of the grass Arrhenatherum elatius originating from a large latitudinal gradient. In general, populations from the North grew smaller and had a lower flowering probability. Toward the North, the absolute plastic response to the different winter conditions as well as heritability for biomass production significantly declined. Genetic differentiation in plant height and probability of flowering were very strong and significantly higher than under neutral expectations derived from SNP data, suggesting adaptive differentiation. Differentiation in biomass production did not exceed but mirrored patterns for neutral genetic differentiation, suggesting that migration-related processes caused the observed clinal trait variation. Our results demonstrate that genetic diversity and trait differentiation patterns for A. elatius along a latitudinal gradient are likely shaped by both local selection and genetic drift. [ABSTRACT FROM AUTHOR]

A introdução de cultivares de forrageiras oriundas de diferentes países pode ser uma opção de transferência de tecnologia a curto prazo para acesso a materiais vegetativos de melhor potencial produtivo. O objetivo deste trabalho foi avaliar cultivares de gramíneas perenes de clima temperado provenientes do Uruguai e Nova Zelândia às condições edafoclimáticas do estado de Santa Catarina, durante os anos de 2010 a 2012. Foram conduzidos, simultaneamente, dois ensaios, em quatro regiões fisiográficas do Estado: Oeste, Meio Oeste, Planalto Sul e Planalto Norte. No ensaio 1 foram avaliados cultivares de Lolium perenne, festulolium e aveia-perene e no ensaio 2 cultivares de Festuca arundinaceae e dáctilo. Houve interação entre cultivares e locais, nos dois ensaios, nos dois anos de avaliação. Azevém-perene e festulolium reduziram significativamente a produção de massa seca (MS) ao longo do período nas regiões Oeste, Meio Oeste e Planalto Norte, sendo recomendado apenas para a região do Planalto Sul. A aveia-perene pode ser indicada para as duas regiões de Planalto, onde perenizou. No ensaio 2, as festucas cv. Epagri 312 (testemunha) e cv. Aurora destacaram-se nos quatro locais, com valores médios de 9 e 7 t ha-1 de MS, respectivamente, para o primeiro e segundo períodos de avaliação.

The objectives of this work were to determine whether and at which seed physiological maturity stage the diquat desiccant affects the tall oat-grass (Arrhenatherum elatius) seed quality and yield, as well as the proper storage period between harvest and sowing. Diquat desiccation was evaluated in applications during milk or dough seed maturation stages. Seeds conventionally produced and stored under traditional storage conditions were used for the analyses. Seed samples were drawn every 30th day after harvest (DAH). After the 240th DAH, samples were drawn every 90th day up the to 690th DAH. The highest yield were obtained by desiccation applied at the beginning of the seed dough stage, with a satisfactory seed quality. Both final germination and seedling growth parameters achieved their maximum values between 180th and 240th DAH. Oat-grass seeds preserved satisfactory level of final germination (75%) up to 420th DAH. The application of diquat desiccant at the beginning of seed dough maturity stage can be a good solution for seed production of tall oat-grass. Early spring is the best sowing period for freshly harvested seeds of tall oat-grass regarding germination and seedling growth.

The paper deals with the yields of Festulolium, Dactylis glomerata, Arrhenatherum elatius and Festulolium-Dactylis glomerata mixture during the growing season and at the end of the growing season. The yields were assessed in the Bohemian-Moravian upland at 560 m a.s.l. A small-plot experiment was established in three repetitions. The assessment was made in three subsequent years. The experiment was annually fertilized with 50 kg . ha−1 N, 30 kg . ha−1 P and 60 kg . ha−1 K. Evaluated were dry matter yields and RYT values (Relative Yield Total) in the mixture of Festulolium and Dactylis glomerata. In summer, the sward was used either for one cut (harvest in early June) or two cuts (harvests in early June and late July). At the end of the growing season, the stand was harvested in October or in November or in December. Yields of the first cut in early June ranged from 5.90 to 9.12 t . ha−1. Yields of the second cut in late July ranged from 1.05 to 4.60 t . ha−1. Statistic difference between the species was significant (P < 0.05) in the respective cuts. Total yields of dry matter in the growing season ranged from 7.51 to 10.05 t . ha−1. Number of cuts and year showed a statistically highly significant influence (P < 0.01) on DM yields. The mixture of Festulolium and Dactylis glomerata exhibited an additive relation (RYT = 1) in the first cut and an antagonistic relation (RYT < 1) in the second cut. At the end of the growing season, the yields ranged from 0.71 to 2.27 t . ha−1. Average yields of one-cut swards (harvested in summer in early June) were at the end of the growing season 2.27 t . ha−1 and average yields of two-cut swards (harvested in summer in early June and late July) were 0.79 t . ha−1. From October to December, the yields were decreasing from 1.78 to 1.32 t . ha−1. Species, number of cuts in summer, harvest date at the end of the growing season and year showed a statistically highly significant influence (P < 0.01) on dry matter yields. In the first two production years, the mixture of Festulolium and Dactylis glomerata exhi­bi­ted an antagonistic relation (RYT < 1) at the end of the growing season. In the third production year, the relation between Festulolium and Dactylis glomerata as expressed by the RYT value could be identified as synergic (RYT > 1).

Ergosterol is a natural compound with steroidic structure produced mainly by fungi. Due to this, it is considered as a marker of fungal spoilage. In this work, the content of ergosterol was monitored in samples of three forage crops (Festuca arundinacea x Lolium multiflorum, Dactylis glomerata, Arrhenatherum elatius) during period October–December 2005 and different term of summer harvesting (June or July). There were adapted and applied liquid chromatographic method with fotometric detection in ultraviolet region for determination of this compound. It was found, that the content of ergosterol strongly increased in all december’s samples with small variations between all three forage crops. Samples, where the summer harvest was performed in July had significantly lower content of ergosterol. Obtained results showed that level of monitored compounds was under limits in all samples.

Copyright of Revista de Ciencias Agroveterinarias is the property of Revista de Ciencias Agroveterinarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As causal agents of bacterial wilt in pastures and meadows, bacteria of the species Xanthomonas translucens are a serious issue in forage grass production. So far, only little is known about host-pathogen interactions at the molecular level and the lack of comprehensive genome data impeded targeted breeding strategies towards resistant forage grass cultivars. Here we announce the draft genome sequences of three grass-pathogenic Xanthomonas translucens pathotype strains, i.e. pv. arrhenatheri LMG 727, pv. poae LMG 728 and pv. phlei LMG 730 isolated from Arrhenatherum elatius (L.) P. Beauv. ex J. Presl & C. Presl (Switzerland), Poa trivialis L. (Switzerland) and Phleum pratense L. (Norway), respectively. The genomes of all three strains revealed a non-canonical type III secretion system and a set of 22 type III effectors as common virulence-related traits. Distinct inter-pathovar differences were observed for the lipopolysaccharide biosynthesis gene cluster and the presence of nonribosomal peptide synthetases. [ABSTRACT FROM AUTHOR]

Species-rich semi-natural grasslands play an essential role in the conservation of European biodiversity. To restore them, existing grasslands may be used as a seed source. A key factor for successful restoration is the transfer of all species of the plant community to the site being restored. This approach, however, often poses practical problems due to variations in species phenology, so that only time-staggered harvesting allows the seeds of many species to be collected. Poor harvesting methods may reduce the number of species transferred from the donor to recipient site. The effects of harvesting at various time points by various methods were evaluated here in a restoration experiment on an ex-arable field in Northern Italy. Propagation materials from the first or second regrowth (or both) of a meadow dominated by Arrhenatherum elatius were collected by four harvesting methods. The materials were spread at the sowing density between 830 and 14360 seeds m −2 . Species composition and structure of the vegetation were examined during 6 years. Untransferred species were almost exclusively those not present at harvesting as mature seed. Compared with materials from one regrowth period, materials from both regrowth periods significantly increased the number of transferred species per plot (26.5 vs. 28.5, respectively) and the absolute transfer rate (64% vs. 75%). Higher sowing density yielded a greater number of positive than negative effects. It favored stable establishment of donor site species and significantly reduced the presence of weeds. Nonetheless, due to the initial dominance of species with high sowing density, evenness of the restored plots was lower than that at the donor site but increased with time, at least under low- and medium-sowing-density conditions. Multiple harvesting at time points when several species with mature seed are present increases the species transfer rate. Medium sowing density positively affects restoration development because it promotes the establishment of donor site species with lower sowing density, prevents species with the highest density from dominating the vegetation during the first few years, and reduces weed cover. [ABSTRACT FROM AUTHOR]

There is increasing pressure to apply cattle slurry on Arrhenatherion grasslands in Central Europe, but intensive manuring can decrease their natural value. We searched for an N application rate which represents an acceptable compromise between farming requirements for high soil fertility and adequate herbage production, environmental protection requirements for balanced applications of nutrients and nature conservation requirements for species-rich grasslands. We applied different annual rates of cattle slurry (0, 60, 120, 180, 240 kg N ha −1 ) on moderately dry Arrhenatherion grasslands over six years. Slurry application positively affected soil fertility by increasing pH, as well as P, K and Mg availability, without any effect on organic C and the total N content. The mean annual herbage yield was 2.58, 3.56, 4.40, 5.75 and 6.09 t ha −1 in 0, 60, 120, 180 and 240 treatments, respectively. Concentrations of N, P and K in herbage slightly increased with slurry application, while the concentration of Ca decreased. There was no surplus of N, K and Ca up to an N application rate of 120 kg ha −1 , and there was only a slight surplus of P and Mg. In S3 and S4 treatments, the main change in vegetation was an increase in graminoids cover, accompanied by a decrease in the cover of legumes and short forbs, without any significant effect on the species richness of vascular plants. Slurry application at annual rates up to 120 N ha −1 seems to be an acceptable compromise, and we recommend setting this limit for application of cattle slurry on Arrhenatherion grasslands. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Ciencias Agroveterinarias is the property of Revista de Ciencias Agroveterinarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of traffic on the content of lead and cadmium in grass morphological parts-leaves, shoots, and inflorescences-was studied. The samples were taken on a part of the European route E30 (Siedlce by road). The following plants were tested: Dactylis glomerata, Arrhenatherum elatius, and Alopecurus pratensis. During the flowering of grasses, the plant material was collected at distances of 1, 5, 10, and 15 m from the edge of the road, on the strip of road with a length of 9 km. In the collected plant parts, the content of lead and cadmium using the atomic absorption spectroscopy (AAS) method was determined. The effect of distance from the road on the content of lead and cadmium was evaluated using regression equations. Average lead content in the above parts of tested grass species was 3.56, while cadmium 0.307 mg kg dry matter (DM). Lead content in plants of Alopecurus pratensis (average 4.11 mg kg DM) was significantly higher than in other grasses. The lowest cadmium content, significantly different from the other species, was found in plants of Arrhenatherum elatius (0.251 mg kg DM). Distance of sampling sites from the roadway significantly affects the differences in the content of cadmium and lead in plants. Analyzed aboveground plant organs of studied grasses were significantly different in contents of lead and cadmium. There were species differences in the proportions of cadmium concentration in various organs of plants. The obtained results indicate the possibility of species composition selection of grassland sward in areas with a higher risk of heavy metals associated with dust sedimentation. [ABSTRACT FROM AUTHOR]

Growth of perennial grasses in the fall represents a balance between an extended growing season and increased vulnerability to frost. Within species along latitudinal gradients, plants may exhibit ecotype-specific sensitivities to the temperature and photoperiod cues that influence cold acclimation. Therefore, it is unclear for a given latitude how climate warming will alter the timing and extent of cold acclimation, and thus vulnerability to frost events. We evaluated relative temperature and photoperiod sensitivities during simulated cold acclimation for two northern (Swedish) and two southern (Italian) ecotypes of the common forage grass Arrhenatherum elatius. Three temperature levels (Templow: 3 °C, Temphigh+low: 8 °C followed by 3 °C, and Temphigh: 8 °C) were crossed with 2 photoperiod levels (Photoshort: 6 h, and Photolong: 12 h) and administered to the plants for a three week acclimation period. All plants were then frozen at −8 °C for 1 d, and post-frost growth was measured after 3 weeks. Temphigh and Photolong increased growth prior to frost, but resulted in decreased growth after frost. The effects of temperature on sugar concentration, biomass and flower presence depended on photoperiod, with temperature only influencing sugar concentration and flowering at Photoshort, while Photolong increased biomass only at the high temperature. The faster growth rate of southern A. elatius ecotypes before frost, in combination with sufficient cold acclimation, resulted in higher biomass accumulation after frost. The faster growth habit of southern ecotypes may be advantageous in accumulating higher summer biomass even after moderate frost events in the fall. [ABSTRACT FROM AUTHOR]

A novel tritimovirus of the family Potyviridae was isolated from tall oatgrass, Arrhenatherum elatius, exhibiting mosaic symptoms. The virus, for which the name tall oatgrass mosaic virus (TOgMV) is coined, has a filamentous particle of 720 nm and is associated with pinwheel inclusion bodies characteristic of members of the family Potyviridae. The virus was mechanically transmitted to tall oatgrass seedlings, which subsequently exhibited mosaic symptoms. The experimental host range was limited to a few monocot species. The complete genome sequence of TOgMV was determined to be 9359 nucleotides, excluding the 3' polyadenylated tail. The viral RNA encodes one large putative open reading frame of 3029 amino acids with a genome organization typical of monopartite potyvirids. Pairwise comparison of putative mature proteins and proteinase cleavage sites indicated that TOgMV is most closely related to members of the genus Tritimovirus. Phylogenetic analysis of the complete polyprotein and CP sequences of representative members of the family Potyviridae indicate that TOgMV is a distinct tritimovirus naturally infecting tall oatgrass. [ABSTRACT FROM AUTHOR]

Experimental studies that explore the possible causes of ploidy distributions and niche differentiation are rare. Increased competitive ability may be advantageous for survival in dense vegetation and may strongly affect local and regional abundances of cytotypes and potentially contribute to invasion success. We compared survival, growth and reproduction of plants originating from bulbils of three cytotypes (2n = 4x, 5x, 6x) of Allium oleraceum growing with and without a competitor ( Arrhenatherum elatius). There was a strong negative effect of competition but no effect of ploidy or ploidy × competition on survivorship, height and total dry mass of A. oleraceum, i.e. no support for different competitive abilities of the ploidy levels. However, slightly different responses of populations to competition treatments within all cytotypes suggest differentiation within cytotypes. Under competition, plant survivorship was low, surviving plants were small, had low dry mass and produced neither sexual nor asexual propagules. Without competition, plant survivorship was high, and cytotypes differed in three traits after 2 year's growth: dry mass of flowers, number of flowers and ratio of the dry mass of sexual to asexual propagules all decreased with increasing ploidy level. We additionally tested tetra- and pentaploids as to whether plants originating from different types of propagule (bulbils, seeds) differ in survivorship, growth and reproduction when growing with and without a competitor. Plants originating from bulbils had higher survivorship, were more robust, flowered earlier and produced more propagules when compared to plants originating from seeds and grown without competition. Under competition, differences in performance between plants originating from seeds and bulbils mostly disappeared, with higher survivorship only for plants originating from bulbils. [ABSTRACT FROM AUTHOR]

The application of vegetation cover for the phytomanagement of heavy metal-polluted soils needs prior investigation on the suitability of plant species. In this study, behaviors ofArrhenatherum elatiusandSonchus transcaspicus,two native perennial grasses that currently grow in a mine tailing, were investigated through plant metal concentration, phytotoxicity and their detoxification responses. Both of the species accumulated Ni, Cu, Cd, Co, Mn, Pb, Cr, and Zn in shoots far below criterion concentration as a hyperaccumulators; thus, neither of them were found to be hyperaccumulators.A. elatiusaccumulated metals in roots and then in shoots, on the contrary, inS. transcaspicusmetals were preferentially accumulated in shoots. Plants exposure to such metals resulted in oxidative stress in the considered organs as indicated by the changes in chlorophyll fluorescence, chlorophyll contents, malondialdehyde (MDA) levels and antioxidative enzyme activities.A. elatiusseemed to be more affected by metal-induced oxidative stress thanS. transcaspicus.Correspondingly,S. transcaspicusshowed a greater capacity to adapt to metal-induced oxidative stress, depending on more effective antioxidative defense mechanisms to protect itself from oxidative damage. These findings allowed us to conclude that both of these plant species could be suitable for the phytostabilization of metal-polluted soils. [ABSTRACT FROM PUBLISHER]

In this study assessed the share of harvested yield and share of root stem bases and stolon biomass in biological yield of 6 grass species grown in pure sowing. The biological yield included harvested yield from 3 regrowth and biomass of RSS (roots, sward and stubble), which was taken after 3th cut. The highest biological yield was observed in Festuca rubra, next in Arrhenatherum elatius and Poa pratensis, and the smallest in Holcus lanatus and Agropyron repens. In F. rubra harvested yield held 13.8% of biological yield, and RSS biomass held 86.2%. In contrast, in H. lanatus harvested yield was 44.7% and RSS biomass was 55.3% of biological yield [ABSTRACT FROM AUTHOR]

Abstract: Alfalfa, teff, oat, and wheat hays were fed to eight mature horses to determine voluntary intake of each hay type. After a 2-week adaptation period during which each horse was offered all four hay types each day, a 4-week study was conducted in which two horses were offered each type of hay each week, usually at the rate of 2.2% of initial body weight. Refused feed was collected and weighed the last 5 days of each week to calculate voluntary intake. Horses consumed significantly more alfalfa hay than the other hays. Wheat and teff hays were consumed in significantly lower amounts than alfalfa, but significantly more than oat hay. Across the 5 days during which voluntary intake was measured each week, hay consumption increased each day, reaching levels significantly greater than day 1 by day 4, when measured as a percentage of body weight, and day 5 when measured as a percentage of feed offered. Only alfalfa hay, at the amount consumed, met 100% of nutrient requirements for digestible energy, crude protein, lysine, calcium, and phosphorus for horses in maintenance condition. Teff hay met all nutrient requirements except digestible energy. Neither wheat nor oat hays met 100% of any of these nutrient requirements. Alfalfa and teff hays averaged about 12% nonstructural carbohydrate content (NSC), whereas wheat and oats hays contained about 30% NSC. The lower NSC content of the alfalfa and teff hays makes these more suitable for horses with problems related to carbohydrate metabolism or for refeeding starving horses. [Copyright &y& Elsevier]

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Abstract: Surveys were performed along paired transects running from the boundary to the field core and with and without sown grass strips. Their presence affected weed assemblages in the boundaries and over the first metre of the field margins as well as the patterns of weed species distribution. Sown grass strip effect always significantly explained the weed species assemblage in boundaries (23.6%), crop edges (28.4%) and field margins (8.1%) but not in field cores. Sown grass strips enlarged the habitat of boundary species (Plantago lanceolata, Arrhenatherum elatius, Carex sp.). They limited the spread of some species into the field (e.g. Sonchus asper, Anagallis arvensis). Some species were favoured by the establishment of sown grass strips (e.g. Cirsium arvense, Bromus sp., Elytrigia repens). However, sown grass strips acted as a buffer zone for arable species (Alopecurus myosuroides, Viola tricolor, Capsella bursa-pastoris), preventing them to extend their habitat from the fields to the boundaries. With short-term consideration, the establishment of sown grass strips puts areas of arable land aside, but offers an opportunity for many plant species to enlarge their habitat without increasing weediness. [Copyright &y& Elsevier]

Dry grasslands are one of the most species rich and endangered types of vegetation in Europe. In the Czech Republic, dry grasslands are mainly of anthropogenic origin and were formed as a result of grazing after the clear-cutting of thermophilous oak woods. Gradual changes in the farming landscape throughout the 20th century, particularly in the 1960s, resulted in the abandonment of the relatively infertile habitats of dry grasslands. After abandonment, dry grasslands decline and degrade due to the gradual overgrowth of woody species and expansion of perennial tall grasses. In the year 2000, a grazing management program was introduced in the protected areas within the territory of Prague City to maintain the species diversity of dry grasslands. The responses of the expansive grass species, Arrhenatherum elatius L. and multiple woody species (especially, Prunus spinosa L.) to differences in grazing periods were monitored for over a decade . Grazing in spring through the end of June had the greatest impact on the reduction of A. elatius and woody species. Grazing in the height of summer through autumn did not reduce the cover of these plants, and may support the prosperity of both A. elatius and the woody species due to higher levels of nutrients. [ABSTRACT FROM AUTHOR]

Abstract: Evidence exists that plant community diversity influences productivity of individual members and their resistance and resilience during and after perturbations. We simulated drought within the long-term EVENT experimental site in the Ecological-Botanical Garden, University of Bayreuth to understand how Arrhenatherum elatius (L.) responds to water stress when grown in three different plant assemblages. The set up consisted of five replications for each factorial combination of drought and plant assemblages differing in functional diversity. Leaf water potential (ΨL), leaf gas exchange, natural δ13C, plant biomass and cover were measured. Imposed drought had different effects on A. elatius, depending on plant assemblage composition. Severe water stress was however, avoided by slowing down the rate of decline in ΨL, and this response was modified by community composition. High ΨL was associated with high stomatal conductance and leaf photosynthesis. Biomass production of A. elatius increased due to drought stress only in the least diverse assemblage, likely due to increased tillering and competitive advantage against neighbors in the drought-treated plants. Our results indicate that beneficial traits among plant species in a community may be responsible for the enhanced capacity to survive drought stress. Resistance to drought may, therefore, not be linked to species richness, but rather to the nature of interaction that exists between the community members. [Copyright &y& Elsevier]

Abstract: The frequency of extreme drought events is projected to increase under global climate change, causing damage to plants and crop yield despite potential acclimation. We investigated whether grasses remain acclimated to drought even after a harvest and remember early summer drought exposure over a whole vegetation period. For this, we compared the response of Arrhenatherum elatius plants under a second, late, drought (they were pre-exposed to an early drought before), to plants exposed to a single, only late, extreme drought. Surprisingly, the percentage of living biomass after a late drought increased for plants that were exposed to drought earlier in the growing season compared to single-stressed plants, even after harvest and resprouting after the first drought. Relative leaf water content did not differ between the two treatments. Net photosynthesis was non-significantly reduced by 25% in recurrent drought treatment. Maximum quantum efficiency (F v/F m) and maximum fluorescence (F m) were reduced in plants that were exposed to recurrent drought. These findings indicated improved photoprotection in double-stressed plants. Our results provide first hints towards a “drought memory” over an entire vegetation period, even after harvest and resprouting. However, the advantage of improved photoprotection might also cause reductions in photosynthesis that could have adverse effects on crop yield under more severe or longer droughts. [Copyright &y& Elsevier]

The aim of this work was to jointly study non-mycorrhizal (dark septate fungi) and mycorrhizal (arbuscular mycorrhizae) colonization along a large range of heavy metal pollution in soil in order to determine the effective contribution of each type of endophytes in relation to heavy metal uptake and tolerance. Hence, eight sites were chosen in the mining area of northern France with respect both to a large range of heavy metal contamination (Cd, Pb, Zn) and monospecific colonization by Arrhenatherum elatius. Root colonization with both arbuscular mycorrhizae (AM) and dark septate fungi (DSF) as well as spore density in rhizospheric soil were estimated in relation to soil characteristics. Mycorrhizal infestation (hyphae, arbuscules and vesicles) was adversely affected by soil pollution almost to exclusion. The intensity of colonization with DSF was very low in presence of AM in non-contaminated soils but higher in polluted soils. The effect of the fungal colonization on the heavy metal tolerance of Arrhenatherum elatius is discussed. [ABSTRACT FROM AUTHOR]

Abstract: The response of an ecosystem to disturbance reflects its stability, which is determined by two components: resistance and resilience. We addressed both components in a study of early post-fire response of natural broadleaved forest (Quercus robur, Ilex aquifolium) and pine plantation (Pinus pinaster, Pinus sylvestris) to a wildfire that burned over 6000ha in NW Portugal. Fire resistance was assessed from fire severity, tree mortality and sapling persistence. Understory fire resistance was similar between forests: fire severity at the surface level was moderate to low, and sapling persistence was low. At the canopy level, fire severity was generally low in broadleaved forest but heterogeneous in pine forest, and mean tree mortality was significantly higher in pine forest. Forest resilience was assessed by the comparison of the understory composition, species diversity and seedling abundance in unburned and burned plots in each forest type. Unburned broadleaved communities were dominated by perennial herbs (e.g., Arrhenatherum elatius) and woody species (e.g., Hedera hibernica, Erica arborea), all able to regenerate vegetatively. Unburned pine communities presented a higher abundance of shrubs, and most dominant species relied on post-fire seeding, with some species also being able to regenerate vegetatively (e.g., Ulex minor, Daboecia cantabrica). There were no differences in diversity measures in broadleaved forest, but burned communities in pine forest shared less species and were less rich and diverse than unburned communities. Seedling abundance was similar in burned and unburned plots in both forests. The slower reestablishment of understory pine communities is probably explained by the slower recovery rate of dominant species. These findings are ecologically relevant: the higher resistance and resilience of native broadleaved forest implies a higher stability in the maintenance of forest processes and the delivery of ecosystem services. [ABSTRACT FROM AUTHOR]

The use of local provenances in restoration, agriculture and forestry has been identified as measure to sustain biological diversity and to improve local productivity. However, the delineation of regional provenances is challenging because it requires the identification of well-defined groups based on spatiogenetic differentiation and/or the evidence of local adaptation. In this study, we investigate genetic variation at 186 AFLP loci in 46 European accessions of the important grassland species Arrhenatherum elatius and ask (1) whether genetic variation within accessions differs between European geographical regions; (2) at which spatial scale populations are structured across Europe and (3) whether putatively adaptive markers contribute to this pattern and whether these markers can be related to climatic site conditions. Basic expectations of population genetics are likely to be altered in autotetraploid species, thus, we adopted a band-based approach to estimate genetic diversity and structuring. Compared to other grasses A. elatius showed high genetic diversity and considerable differentiation among accessions (ΦST = 0.24). Accessions separated in a Western European and a Central/Eastern European group, without further structure within groups. A genome scan approach identified four potentially adaptive loci, whose band frequencies correlated significantly with climatic parameters, suggesting that genetic differentiation in A. elatius is also the result of adaptive processes. Knowledge on adaptive loci might in the long run also help to adapt ecosystems to adverse climate change effects through assisted migration of ecotypes rather than introduction of new species. [ABSTRACT FROM AUTHOR]

In a 2-year field experiment, morphological development and measures of the nutritive value of herbage for livestock during primary growth in Meadow foxtail, Tall oatgrass, Cocksfoot, Perennial ryegrass and Yorkshire fog were investigated. All measured variables were affected significantly by both species and sampling date, and their interaction ( P < 0·001), in the period of primary growth. Changes with time in mean stage weight for Meadow foxtail and Cocksfoot were different from the other species due to their indeterminate growth habits. Mean stage weight of Tall oatgrass and Yorkshire fog increased more rapidly than that of Perennial ryegrass with time. Changes in mean stage weight with time were described by linear, parabolic and sigmoid relationships. Crude protein (CP) concentration of herbage was higher for Cocksfoot and Meadow foxtail than for Perennial ryegrass. A parabolic relationship of CP concentration with time was typical for all the species. Concentrations of neutral-detergent fibre (NDF) and acid-detergent fibre (ADF) in herbage of the species differed most during the mid-period of primary growth. Their increases with time showed curvilinear (sigmoid and parabolic) relationships. Perennial ryegrass had lower concentrations of both NDF and ADF in herbage than the other species. Differences between the in vitro dry matter (DM) digestibility among the grasses increased in mid- and late periods of primary growth. Perennial ryegrass had higher values for in vitro DM digestibility but the difference from other species was small in the early period of primary growth and from cocksfoot in the late period of primary growth. In vitro DM digestibility showed, in most cases, a sigmoid and, in others, a linear decrease with time. Principal component analysis showed that perennial ryegrass and meadow foxtail were the most distinctive of the species in characteristics relating to morphological development and the nutritive value of herbage to livestock. [ABSTRACT FROM AUTHOR]