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Intercropping perennial legumes with trees can reduce Nitrogen (N) losses, due to the high amount of N accumulated in stable forms in the soil and permanent soil cover during the whole year. Although N cycling improvement in mature agroforestry systems (AFS) was well documented, there is a lack of knowledge regarding systems in transition to AF. In this work, we studied the association of two perennial forage crops, namely ryegrass (Lolium multiflorum Lam.) and sulla (Hedysarum coronarium L.), with 1-year old poplars, to evaluate: (i) the agronomic performance of sulla and ryegrass with vs. without intercropped poplar trees; (ii) the N-fixing ability of sulla in association with trees; (iii) the N transfer effect from sulla and growth promoting effect on poplar; and finally (iv) the nitrate leaching reduction due to the presence of poplar trees associated to forage crops. The layout was arranged in a two-factor randomized complete blocks design (RCB) with three replicates. The first factor tested (crop species) implied two different swards, namely sulla and ryegrass. The second factor (cropping system) included two different systems: PAST i.e., a pastoral system without trees, and SIPAST, i.e., a silvo-pastoral system with one poplar tree row beside the sward. Sulla resulted more productive than ryegrass when associated with trees (+35%). No clear trend was observed about the tree influence on N-fixation in sulla, but the amount of N fixed resulted higher in in sulla grown in the SIPAST near the trees (+35%). Poplar plants, even in the first year after planting, resulted effective yet in reducing the nitrate flux from the crops towards ditches. Further investigations are needed to study other swards in young AF and better understand the N dynamics; in particular, it could be worth to assess the nutrient flux in the soil solution. [ABSTRACT FROM AUTHOR]

Soil microorganisms play a vital role in increasing the availability of phosphorus (P) for plants through mineralization of organic P and solubilization of precipitated P compounds. In this two-year study, we analyzed several P-solubilizing microorganisms (PSMs) of the genus Bacillus and their consortiums for the ability to release soluble P from apatite concentrates of various grinding degrees using ryegrass (Lolium multiflorum Lam.) as a model plant. The effects were accessed by analyzing plant growth and nutrient assimilation. The greatest effect on root system development and plant biomass accumulation (dry weight) was observed for the apatite concentrate of standard grinding in combination with Bacillus megaterium BI14 and Bacillus subtilis BI2 and Bacillus velezensis BS89 strains. Although the introduction of apatite concentrates led to an increase in the content of total strontium in soil, the levels of strontium did not exceed the maximum allowable concentration, and the accumulation of mobile strontium by plants was unchanged; importantly, the use of tested PSMs led to a decrease in the strontium content in the green biomass of ryegrass. Our results indicate that biologized apatite concentrates in combination with PSMs represent promising fertilizers that can provide a source of soluble P to be readily assimilated by plants. [ABSTRACT FROM AUTHOR]

Purpose: The incorporation of ryegrass (Lolium multiflorum Lam.; RG), a winter manure, could partly replace chemical N and reduce N loss during the succeeding rice seasons, but little is known about its impact on greenhouse gas emission. This study investigated the effect of different RG-urea substitution ratios (0% RG and 100% urea, 25% RG and 75% urea, 50% RG and 50% urea, 75% RG and 25% urea, 100% RG and 0% urea,) on net C and N mineralization, CH4 and N2O emissions in a paddy soil. Methods: Gas samples for CH4 and N2O fluxes were collected by using a closed chamber and determined by chromatograph method. Net C and N mineralization from the incorporated RG residue were tested by a mesh bag method. Results: Net C and N mineralization from RG followed a single exponential decay model, with 95.5%-97.8% of the original C and 98.7%-99.3% of N released during 192 days. The RG-urea substitution ratio increased CH4 emission, but was negatively correlated with N2O emission. In comparison with 0% substitution, global warming potential (GWP) and greenhouse gas intensity (GHGI) were not significantly different for the 25% and 50% RG substitutions, but were significantly higher for the 75% and 100% substitutions (P < 0.05). Soil redox, C and N remaining in litter residue were key characteristics explaining CH4 emission, while NH4+-N and NO3−-N were correlated with N2O emission. Conclusion: The increased GWP by CH4 emission after RG incorporation could be offset by N2O reduction when RG-urea substitution ratio was 50% or less. [ABSTRACT FROM AUTHOR]

Weeds are a major impediment to crop and pasture production and profitability in Australian farming systems, and knowledge of their occurrence is vital in devising weed management solutions. This study examined the relationships between weed and crop species from observations made during surveys of randomly selected fields in grain and/or pasture production. Between 2013 and 2017, 996 fields across New South Wales (NSW) were surveyed to record the occurrence and density of weed species. Annual ryegrass (Lolium rigidum) (69% of fields), wild oats (Avena spp.) (60%), and sowthistle (Sonchus oleraceus) (34%) were the most common species identified, with a total of 65 weed species recorded to be occurring in NSW cropping fields. Densities of occurring weeds were low, at one plant per square metre or less. Multiple species of wild oats were recorded, with their occurrence varying between survey regions; for example, Avena sterilis subsp. ludoviciana was more prevalent in the north and Avena fatua in the south. Differences in weed species occurrence were noted between this survey and those previously conducted in NSW, with marked increases in annual ryegrass and sowthistle, and this is attributed to the change in crop production practices between survey periods. The study of variable distribution patterns of weed species across cropping systems allows for informed decision-making regarding weed management research and development planning. [ABSTRACT FROM AUTHOR]

Context: Annual ryegrass (Lolium rigidum) is a major weed of crop production in southern Australia that readily develops resistance to herbicides. Resistance increases both yield losses and control costs associated with this species. Aims: This study aimed to gauge the extent and distribution of resistance to herbicides in L. rigidum across south-eastern Australian grain production systems by collecting seed from randomly selected fields. Methods: A total of 1441 weed populations were collected through random surveys conducted over 5 years across 13 agricultural regions of four states with these samples then tested for resistance to eight herbicides from six modes of action. Key results: Resistance to diclofop-methyl and sulfometuron-methyl was most common, being present in 64% and 63% of populations respectively. Glyphosate resistance was present in 4% of populations collected. Only 15% of populations collected were susceptible to all herbicides tested. Large differences in resistance occurred between the 13 regions surveyed with resistance to diclofop-methyl ranging from 15% to 86% of populations and sulfometuron-methyl from 12% to 96%. Resistance to post-emergent herbicides tended to be higher than pre-emergent herbicides. Multiple resistance was common with 60% of populations collected having resistance to two or more herbicide modes of action. Conclusions: There were significant differences in the extent of multiple resistance in L. rigidum populations collected from individual regions suggesting that the rates of resistance evolution have differed between regions. Implications : The high incidence of herbicide resistance in L. rigidum populations randomly collected from south-eastern Australian cropping fields highlights the need for the adoption of additional weed control practices to mitigate the impact of this species on grain production systems. Herbicide resistant weeds are a major threat to crop production, with annual ryegrass being the major species of concern in Australia. Surveys of south-eastern Australia conducted over a 5 year period found over 60% of populations were resistant to two or more herbicide groups and only 15% of ryegrass populations were susceptible to all tested herbicides. The high level of resistance found across south-eastern Australia highlights the need for farmers to adopt non-herbicide practices, in conjunction with herbicides, to control this species. [ABSTRACT FROM AUTHOR]

More than 50% of agricultural land is threatened by water erosion in the Czech Republic. With respect to soil erosion, maize (Zea mays L.) belongs to the most problematic crops; one of the possibilities to increase protection against erosion is intercropping. In this study, we attempted to find out the effects of individual intercrops and their mixtures (sown 4--6 weeks after sowing maize) or a mixed culture (maize plus lupine) on the soil losses and surface runoff in the period 2019--2021. The study was realised in a sugar beet growing region (Haplic Luvisol); a field rainfall simulator was used. From the used variants with Lolium perenne L., Trifolium repens L., Vicia villosa Roth, Lolium multiflorum Lam., Festuca arundinacea Schreb., Triticum aestivum L. or a mixture (Vicia villosa plus a Trifolium hybrid diploid), the variants with Lolium perenne, Lolium multiflorum, Vicia villosa or Vicia villosa plus the Trifolium hybrid diploid, established between the maize rows (hybrid maize, cultivar Walterinio) on May 27, were the most efficient in case of both the soil losses and runoff reductions in the year 2019. For example, Triticum aestivum between the maize rows mostly reduced the soil losses and the surface runoff was similar (or higher) compared with the control (maize without any intercrop). The variant with Trifolium repens had mostly higher (or similar) soil loss values (compared with the control); in this variant, the runoff was lower compared with the control. We proved our hypothesis with regards to the higher reduction in the soil losses than with the runoff in the variant with Lolium perenne. The results from the years 2020 (the used variants with Lolium multiflorum, Secale cereale L., Trifolium incarnatum L., Phacelia tanacetifolia Benth., Lolium multiflorum plus Trifolium incarnatum, Lolium multiflorum plus Vicia pannonica Crantz) and 2021 (the variants with Lolium multiflorum, Lolium multiflorum -- early sowing, Secale cereale, Trifolium incarnatum, Phacelia tanacetifolia, Lolium multiflorum plus Trifolium incarnatum, a mixed culture = maize plus Lupinus albus L.) showed the variants with Trifolium incarnatum, the mixture (Lolium multiflorum plus Trifolium incarnatum), Phacelia tanacetifolia (in the year 2020) or the mixture (Lolium multiflorum plus Trifolium incarnatum) and a mixed culture (maize plus Lupinus albus) (2021) had the most positive effect -- the soil loss and surface runoff values were lower when the maize was > 2 m compared with the maize < 1 m. The results obtained in the period 2019--2021 showed the grasses were the most efficient in decreasing the soil losses when the maize was < 1 m and when the maize was > 2 m with the used mixtures. [ABSTRACT FROM AUTHOR]

In this study, it was aimed to determine the effect of microbial inoculants and molasses on the quality and in vitro digestibility of the silages ensiled from the cultivation of different proportions of ryegrass-Hungarian vetch mixtures grown in Central Anatolian conditions. For this purpose, 5% molasses and 10 g/ton (1.25 x 1011 CFU/g) inoculant were added to silages of ryegrass (Lolium multiflorum L.) containing 20%, 40%, 60%, and 80% Hungarian vetch (Vicia pannonica L.), under laboratory conditions. The prepared silages were opened at the end of 60 days and their physical analysis, chemical contents, fermentation parameters, in vitro digestibilities using rumen inocula obtained from cannulated Holstein cow, and energy levels were determined. In the study, it was determined that the microbial inoculant increased the lactic acid level significantly (p < 0.05). In vitro digestibility of organic matter and energy values increased in silages containing 60% HV compared to other silages and with both additives (p < 0.05). The neutral detergent fiber levels increased in mixtures containing 40% and 60% Hungarian vetch (p < 0.05). The increase in the vetch ratio affected the external appearance of the silages negatively (p < 0.05), and the physical properties were adversely affected by the inoculant (p < 0.05). As a result, it was determined that Hungarian vetch can be mixed with ryegrass up to 80% with and without inoculant and molasses additive to obtain high-quality silage. But the highest digestibility values were obtained when Hungarian vetch was mixed at a 60% level. It would be more appropriate to prefer molasses to avoid undesired changes in physical properties. [ABSTRACT FROM AUTHOR]

Aims: An Italian ryegrass cultivar (Lolium multiflorum Lam. cv. Bb2067), selected and bred for increased leaf magnesium (Mg) concentration in the 1970s, reduced the incidence of hypomagnesaemia in sheep under experimental grazings. Here, we report evidence from archival experiments showing that cv. Bb2067 had consistently greater Mg concentrations at multiple sites. We also aimed to quantify variation in leaf Mg concentration among modern perennial ryegrass (Lolium perenne L.), hybrid ryegrass (Lolium perenne × multiflorum), and tall fescue (Festuca arundinacea Shreb.) cultivars. Methods: Data are reported from unpublished 1980s field-plot experiments for cv. Bb2067 and contemporaneous reference cultivars, sown at two UK locations in 1983 and 1984, and from 397 cultivars of modern forage grass in 13 UK-based breeding experiments sampled in spring 2013. Results: Across sites, years and cuts, cv. Bb2067 had a consistently greater leaf Mg concentration and lower potassium (K) concentration and forage tetany index (FTI) than reference cultivars in the 1980s experiments. Seasonal variation in leaf Mg and K concentrations and FTI were observed in the 1980s experiments, with K concentrations being generally greatest and Mg concentrations smallest in spring. Among modern forage grasses, there was large variation in leaf Mg concentration (up to 6.3-fold) and FTI (up to 2.1-fold), both within and between species, which varied independently of yield. Among a subset of hybrid ryegrass cultivars, there is evidence that the high Mg trait is already present in some modern breeding lines, albeit previously unreported. Conclusions: The variation in leaf Mg concentration and FTI among old and new cultivars shows there is considerable potential to breed forages with improved mineral quality to improve livestock health, potentially without compromising yield or other nutritional traits. [ABSTRACT FROM AUTHOR]

The objective of this research was to carry out a survey, through the levels of physical purity, percentage of pure seeds, number of other seeds, and the physiological quality through germination, in the samples of ryegrass seeds analyzed in laboratories accredited by the Ministry of Agriculture, Livestock and Supply in Rio Grande do Sul. Data from 3959 ryegrass samples analyzed from the period 2014 to 2017 were compiled. Quality of the seeds was presented through the percentage of samples within the standards recommended for commercialization, for the variables germination, pure seeds, seeds of cultivated species, wild, noxious, tolerated and noxiously forbidden, in all factors, cultivar, region of origin, category and crop of seed production. Quality of the lots of ryegrass seeds, analyzed by the laboratories of Rio Grande do Sul, obtained in the harvest of 2013 the lowest percentage of lots approved for commercialization, 57.96%, and the harvest of 2014, 2015 and 2016 with 89.60% 91.39% and 91.34%, respectively. In regions where livestock predominates, the percentage of ryegrass seed lots approved for commercialization was lower. [ABSTRACT FROM AUTHOR]

The gray field slug, Deroceras reticulatum, is a key pest of seed crops. There is an increasing interest in developing new chemical controls due to limited management options. Essential oils, being non-toxic to humans and exempt from pesticide registration and residue tolerance requirements under US federal law (Sect. 25(b) of the Federal Insecticide, Fungicide, and Rodenticide Act), could be safe and easily implementable alternatives. In this study, the most toxic essential oils to D. reticulatum adults of 13 plant-derived essential oils and one synthetic toxin (caffeine) were determined based on Lethal Concentration 50 values produced in a laboratory Petri dish bioassay. Thyme, spearmint, and pine oil were the most lethal, causing 50% mortality of D. reticulatum at concentrations of 0.148, 0.153, and 0.176% (v/v), respectively. Thyme and spearmint oil were then tested in a greenhouse microcosm experiment and a separate phytotoxicity assessment. In the greenhouse, slugs were added to containers planted with annual ryegrass (Lolium multiflorum) and the containers were sprayed with either 0.5% (v/v) essential oil emulsion, Slug-Fest (industry standard molluscicide), surfactant control at 1% (v/v), or water control. Both oils caused 97.5% mortality of slugs, performing comparably to metaldehyde. Phytotoxic effects were assessed by spraying oils on seedlings and adult plants of two cultivars each of perennial ryegrass (Lolium perenne) and tall fescue (Festuca arundinacea). No definitive signs of phytotoxicity were observed upon visual inspection, and there were no differences in chlorophyll content or biomass between treated and untreated plants. [ABSTRACT FROM AUTHOR]

The purpose of the study was to examine biochar amendment, phosphorus (P) fertilizer and arbuscular mycorrhizal fungi (AMF) on the yield, nutrient and cadmium (Cd) absorption of Lolium multiflorum in acidic soil. It was shown that mycorrhizal inoculation had no positive influence on the plant shoot biomass and the contents of nitrogen (N), P, potassium (K), calcium (Ca) and magnesium (Mg) in plants at all biochar and P level treatments. Irrespective of mycorrhizal inoculation and P level, biochar amendments markedly elevated the soil available P and K uptake in plant tissues. In contrast, biochar significantly decreased the translocation factor of plants, soil exchangeable Cd, and acid and neutral phosphatase activities, regardless of the mycorrhizal inoculation and P fertilizer. Without P fertilization, biochar amendments significantly promoted shoot P content, while biochar amendments significantly reduced shoot P content when P fertilizer was applied. Without biochar application, P fertilizer application significantly promoted the biomass and N uptake of shoots in both AMF inoculation treatments, while P fertilizer increased these only in the presence of biochar and mycorrhizal inoculation. The increased N content induced by the biochar amendment elevated the shoot N:P ratio and alleviated the N deficiency with P fertilizer input. Thus, we concluded that the addition of biochar and P fertilizer showed more positive effects on the promotion of growth and nutrient uptake of L. multiflorum than AMF grown in acidic Cd-contaminated soils. Image 1 • AMF had no positive influence on shoot biomass and nutrient uptakes. • Biochar markedly elevated soil P level and plant K uptake. • Biochar decreased translocation factor. • Biochar increased shoot N:P ratio with P fertilization. • Biochar and P fertilizer had more positive effects on ryegrass than AMF. [ABSTRACT FROM AUTHOR]

[Objective] to provide the suitable turfgrass varieties for soil bioremediation in Hg2+ contaminated region. [Method] The leaf chlorophyll content, Fv/Fm, soluble sugar content, SOD activity, MDA content, leaf relative conductance and N, P and K accumulation characteristics of four tested turgrass varieties were determined by a pot simulation experiment of Hg2+ stress. [Result] With increase of Hg2+concentration, the leaf chlorophyll content, Fv/Fm and N, P and K accumulation declined continuously, soluble sugar content and SOD activity showed a first rising and then declining trend, and MDA content and leaf relative conductance increased continuously. The leaf chlorophyll content, Fv/Fm, soluble sugar content, SOD activity and N, P and K accumulation of four turgrass varieties under 75-100 mg/kg Hg2+ stress reduced significantly compared with CK but MDA content and relative conductance increased significantly. High Hg2+ concentration had the significant effects on leaf cell membrane permeability and N, P and K accumulation of seedlings of four tested turfgrass varieties, which severely inhibited plant growth and causes death of plants. [Conclusion] The annual ryegrass variety (Shengyan) with the strongest tolerance to Hg2+ stress among four tested turfgrass varieties can be selected as the optimized tufgrass variety for bioremediation of Hg2+-contaminated soil. [ABSTRACT FROM AUTHOR]

Understanding the characteristics of alien species is a prerequisite for any biological study or anti‐invasion management strategy. Lolium rigidum (Poaceae) is an alien species that has become naturalized on the sandy coasts of Japan; however, it exhibits extensive morphological variation, leading to speculation that several taxa of Lolium have become naturalized. Here, we compared the morphology, reproductive biology and genetic structure of this Lolium species by growing individuals from different locations in the same environment to clarify whether the observed morphological variation is genetically based or is caused by intraspecific variation as a result of environmental differences. Principle component analyses of 11 morphological traits separated the study species into two types. Bagging experiments showed that one type exhibited an outcrossing life history, whereas the other type selfed exclusively. Nuclear DNA microsatellite analyses supported this distinction between these morphological types, with no intermediate individuals being found. The outcrossing type exhibited high genetic diversity, whereas the selfing type exhibited almost no polymorphism, reflecting the differences in their breeding systems. Moreover, both types differed from the economically important outcrossing species Lolium multiflorum and Lolium perenne. These two types of Lolium are expected to have different introduction histories and invasive potential on the coasts of Japan. In conclusion, it is important to distinguish between these types through additional biological studies to design effective control measures. [ABSTRACT FROM AUTHOR]

Heavy metals negatively affect soil quality and crop growth. In this study, we compared the tolerance of six ryegrass cultivars to cobalt (Co2+), lead (Pb2+), and nickel (Ni2+) stresses by analyzing their physiological indexes and transcript levels of genes encoding metal transporters. Compared with the other cultivars, the cultivar Lm1 showed higher germination rates and better growth under Co2+, Pb2+, or Ni2+ treatments. After 48 h of Co2+ treatment, the total antioxidant capacity of all six ryegrass cultivars was significantly increased, especially that of Lm1. In contrast, under Pb2+ stress, total antioxidant capacity of five cultivars was significantly decreased, but that of Lm1 was unaffected at 24 h. Staining with Evans blue dye showed that the roots of Lm1 were less injured than were roots of the other five ryegrass cultivars by Co2+, Pb2+, and Ni2+. Lm1 translocated and accumulated lesser Co2+, Pb2+, and Ni2+ than other cultivars. In Lm1, genes encoding heavy metal transporters were differentially expressed between the shoots and roots in response to Co2+, Pb2+, and Ni2+. The aim of these researches could help find potential resource for phytoremediation of heavy metal contamination soil. The identified genes related to resistance will be useful targets for molecular breeding. [ABSTRACT FROM AUTHOR]

set of 15 Italian ( Lolium multiflorum), three hybrid ( L. boucheanum) and 33 perennial ryegrass ( L. perenne) cultivars were evaluated for their rust susceptibility in the field. The cultivars were grown in 2001, 2004 and 2007 at 29, 32 and 27 European sites, respectively. Rust incidence was scored during different growth cycles using a scale from one (no rust) to nine (susceptible). Crown rust ( Puccinia coronata f. sp. lolii) was the most frequently observed rust species on Italian, hybrid and perennial ryegrass during all three experimental years. There was a highly significant difference in mean crown rust scores among Italian and perennial ryegrass cultivars, respectively, in each of the 3 years. The ranking of the cultivars was very consistent across the different sites within each year (with some exceptions), despite a significant interaction of cultivar response with sites. Moreover, the rank order correlations of mean cultivar rust scores were highly significant ( r > 0.9) between the years. Stem rust ( P. graminis f. sp. graminicola) occurred almost exclusively on perennial ryegrass. The cultivars showed significant variation in stem rust susceptibility. Rank order correlations of mean cultivar stem rust scores were mostly significant between sites within each year and highly significant between the years. The ranking of perennial ryegrass cultivars was different depending on whether crown or stem rust was scored. However, the rank order correlation between the mean disease scores of the cultivars for the two pathogens was low but still significant. At a particular site the assessment of crown or stem rust was in most cases very consistent over the period of experimentation. Therefore there was no evidence that rust resistance of an individual cultivar was overcome by the rust pathogen at a particular site over the 7 years of experimentation. [ABSTRACT FROM AUTHOR]