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Food allergies mediated by specific IgE (sIgE) have a significant socioeconomic impact on society. Evaluating the IgE cross-reactivity between allergens from different allergen sources can enable the better management of these potentially life-threatening adverse reactions to food proteins and enhance food safety. A novel banana fruit allergen, S-adenosyl-L-homocysteine hydrolase (SAHH), has been recently identified and its recombinant homolog was heterologously overproduced in E. coli. In this study, we performed a search in the NCBI (National Center for Biotechnology Information) for SAHH homologs in ryegrass, latex, and kiwifruit, all of which are commonly associated with pollen-latex-fruit syndrome. In addition, Western immunoblot analysis was utilized to identify the cross-reactive IgE to banana SAHH in the sera of patients with a latex allergy, kiwifruit allergy, and ryegrass allergy. ClustalOmega analysis showed more than 92% amino acid sequence identity among the banana SAHH homologs in ryegrass, latex, and kiwifruit. In addition to five B-cell epitopes, in silico analysis predicted eleven T-cell epitopes in banana SAHH, seventeen in kiwifruit SAHH, twelve in ryegrass SAHH, and eight in latex SAHH, which were related to the seven-allele HLA reference set (HLA-DRB1*03:01, HLA-DRB1*07:01, HLA-DRB1*15:01, HLA-DRB3*01:01, HLA-DRB3*02:02, HLA-DRB4*01:01, HLA-DRB5*01:01). Four T-cell epitopes were identical in banana and kiwifruit SAHH (positions 328, 278, 142, 341), as well as banana and ryegrass SAHH (positions 278, 142, 96, and 341). All four SAHHs shared two T-cell epitopes (positions 278 and 341). In line with the high amino acid sequence identity and B-cell epitope homology among the analyzed proteins, the cross-reactive IgE to banana SAHH was detected in three of three latex-allergic patients, five of six ryegrass-allergic patients, and two of three kiwifruit-allergic patients. Although banana SAHH has only been studied in a small group of allergic individuals, it is a novel cross-reactive food allergen that should be considered when testing for pollen-latex-fruit syndrome. [ABSTRACT FROM AUTHOR]

Background: With the accumulating omics data, an efficient and time-saving transient assay to express target genes is desired. Mesophyll protoplasts, maintaining most stress-physiological responses and cellular activities as intact plants, offer an alternative transient assay to study target genes' effects on heat and oxidative stress responses. Results: In this study, a perennial ryegrass (Loliumperenne L.) mesophyll protoplast-based assay was established to effectively over- or down-regulate target genes. The relative expression levels of the target genes could be quantified using RT-qPCR, and the effects of heat and H2O2-induced oxidative stress on protoplasts' viability could be quantitatively measured. The practicality of the assay was demonstrated by identifying the potential thermos-sensor genes LpTT3.1/LpTT3.2 in ryegrass that over-expressing these genes significantly altered protoplasts' viability rates after heat stress. Conclusion: This protoplast-based rapid stress regulatory gene identification assay was briefed as 'PRIDA' that will complement the stable genetic transformation studies to rapidly identify candidate stress-regulatory genes in perennial ryegrass and other grass species. [ABSTRACT FROM AUTHOR]

Heavy metal contamination is an urgent ecological governance problem in mining areas. In order to seek for a green and environmentally friendly reagent with better plant restoration effect to solve the problem of low efficiency in plant restoration in heavy metal pollution soil. In this study, we evaluated the effects of three biodegradable chelating agents, namely citric acid (CA), fulvic acid (FA) and polyaspartic acid (PASP), on the physicochemical properties of copper tailings, growth of ryegrass (Lolium perenne L.) and heavy metal accumulation therein. The results showed that the chelating agent application improved the physicochemical properties of copper tailings, increased the biomass of ryegrass and enriched more Cu and Cd in copper tailings. In the control group, the main existing forms of Cu and Cd were oxidizable state, followed by residual, weak acid soluble and reducible states. After the CA, FA or PASP application, Cu and Cd were converted from the residual and oxidizable states to the reducible and weak acid soluble states, whose bioavailability in copper tailings were thus enhanced. Besides, the chelating agent incorporation improved the Cu and Cd extraction efficiencies of ryegrass from copper tailings, as manifested by increased root and stem contents of Cu and Cd by 30.29–103.42%, 11.43–74.29%, 2.98–110.98% and 11.11–111.11%, respectively, in comparison with the control group. In the presence of multiple heavy metals, CA, FA or PASP showed selectivity regarding the ryegrass extraction of heavy metals from copper tailings. PCA analysis revealed that the CA-4 and PASP-7 treatment had great remediation potentials against Cu and Cd in copper tailings, respectively, as manifested by increases in Cu and Cd contents in ryegrass by 90.98% and 74.29% compared to the CK group. [ABSTRACT FROM AUTHOR]

Light intensity plays a critical regulatory role in determining plant yield and quality, and energy consumption in plant factory with artificial light (PFAL). The effects of different light intensities (200, 300, 400, 500, and 600 µmol·m−2·s−1) of light-emitting diodes (LED) red and blue light with ratio 4:1 on growth, quality, nitrogen and amino acid metabolisms of ryegrass were investigated. The results showed the tiller number and shoot fresh weight in ryegrass were increased, while plant height and stem diameter remained stable with the improvement of light intensity. The highest levels of soluble protein, free amino acid, and DPPH free radical clearance rate in photon flux density (PPFD) at 500 µmol·m−2·s−1, and then significantly decreased with light intensity increased. The highest soluble sugar content was found at PPFD of 600 µmol·m−2·s−1, while malondialdehyde (MDA) content remained stable in all treatments. As the light intensity increased, nitrate content decreased, while nitrate reductase (NR) activity and the ammonium content increased. As light intensity was increased from 200 to 600 µmol·m−2·s−1, nitrite reductase (NiR) activity first decreased and then increased. Moreover, glutamate and cysteine contents increased first and then decreased, while glutamate synthase (GOGAT), glutamine synthase (GS), glutamate dehydrogenase (GDH), and cysteine synthases (CS) activities increased continuously with light intensity. Light intensity was significantly correlated with the parameters of growth, quality, nitrogen and amino acid metabolisms in ryegrass. It was recommended that PPFD at 400–500 µmol·m−2·s−1, photoperiod of 16 h/d was suitable for ryegrass high-efficient production in PFAL with relatively low energy cost. [ABSTRACT FROM AUTHOR]

The co-allocation of photovoltaic arrays with crops presents a promising strategy to mitigate the conflict between photovoltaics and agricultural land. However, there is a notable lack of quantitative research on the impact of agrivoltaic system on land quality in fragile areas. In this study, peanuts (Arachis hypogaea) and ryegrass (Lolium perenne) were cultivated in photovoltaic array in the dry–hot valley of southwest China, with an off-site native land serving as the control. Sixteen soil physicochemical and biochemical parameters were measured in the gap and under-panel and control area. Results demonstrated that the agrivoltaic system significantly enhanced soil moisture, organic carbon, nitrogen–phosphorus–potassium nutrients, microbial biomass, and urease activity. It also led to varying degrees of increase in soil pH and electrical conductivity, along with reduced soil sucrase and phosphatase activity. In comparison to the control, the agrivoltaic system notably improved soil quality and multifunctionality. Specially, gap cultivation had a more pronounced positive impact on soil quality than under-panel cultivation, and the cultivation of peanuts had a greater effect on soil quality and multifunctionality improvement than ryegrass. This study provides fundamental data to support the improvement of land quality in photovoltaic developed regions, and to alleviate the conflict between photovoltaics and agricultural land. [ABSTRACT FROM AUTHOR]

The study aimed to investigate the impact of different levels of organic fertilizer on the yield, nutrient composition, and fermentation quality of ryegrass. Using the Bond variety of polyfloral ryegrass as the experimental material, four organic fertilizer application levels were set at 750 (Group 1), 1 000 (Group 2), 1 250 (Group 3), and 1 500 kg/hm2 (Group 4). The changes in yield, nutrient composition, and fermentation quality of polyfloral ryegrass under different levels of organic fertilizer application were explored. The results showed that the plant height and fresh grass yield of ryegrass in Group 3 and Group 4 were significantly higher than those in Group 1 ( P<0.05). The dry hay yield of ryegrass in the first cut was significantly higher in Group 3 compared to Group 1 and Group 2 ( P<0.05), and the dry hay yield in the third cut was significantly higher in Group 2, Group 3, and Group 4 compared to Group 1 ( P<0.05). The contentrations of crude protein of ryegrass in Group 3 and Group 4 were significantly higher than that in Group 1 and Group 2 ( P<0.05), and the contentration of neutral detergent fiber was significantly lower than that in Group 1 ( P<0.05). The contentration of crude protein of ensiled ryegrass in Group 3 and Group 4 was significantly higher than that in Group 1 ( P<0.05), while the contentrations of ammonia nitrogen, neutral detergent fiber, and acid detergent fiber were significantly lower than that in Group 1 ( P<0.05). The concentrations of lactic acid and acetic acid of ensiled ryegrass in Group 2, Group 3, and Group 4 were significantly higher than that in Group 1 ( P<0.05), and the concentration of lactic acid in Group 3 was significantly higher than that in Group 2 and Group 4 ( P<0.05). The contentration of crude protein of fermented ryegrass in Group 3 and Group 4 was significantly higher than that in Group 1 and Group 2 ( P<0.05), and the contentrations of neutral detergent fiber and acid detergent fiber were significantly lower than that in Group 1 ( P<0.05). The study indicates that applying 1 250 kg/hm2 of organic fertilizer during the cultivation of ryegrass resulted in better grass yield, nutrient composition, and fermentation quality. [ABSTRACT FROM AUTHOR]

Accurately monitoring Canopy Nitrogen Concentration (CNC) is a prerequisite for precision nitrogen (N) fertiliser management at the farm scale with carbon and N budgeting across the landscape and ecosystems. While many spectral indices have been proposed for CNC monitoring, their applicability and accuracy are often adversely affected by confounding factors such as aboveground biomass (AGB), crop type, growth stages, and environmental conditions, limiting their broader application and adoption; with AGB being one of the most dominant signals and confounding factors at canopy scale. The confounding effect can become more challenging as AGB is also physiologically linked with CNC across the growth stages. Additionally, the interplay between index form, selection of optimal wavebands and their bandwidths remains poorly understood for CNC index design. This study proposes robust and cost-effective 2- and 4-waveband multispectral (MS) CNC indices applicable across a wide range of crop conditions. We collected 449 canopy reflectance spectra (400–980 nm) together with corresponding CNC and AGB measurements across four growth stages of ryegrass (winter and summer), and five growth stages of barley (winter-spring) in Victoria, Australia, in 2018 and 2019. All possible waveband (400–980 nm) combinations revealed that the best combination varied between seasons and crop types. However, the visible spectrum, particularly the blue region, presented high and consistent performance. Bandwidths of 10–40 nm outperformed either very narrow (2 nm) or very broad bandwidths (80 nm). The newly developed 2-waveband index (416 and 442 nm with 10-nm bandwidth; R2 = 0.75 and NRMSE = 0.2) and 4-waveband index (512, 440, 414 and 588 nm with 40-nm bandwidth; R2 = 0.81 and NRMSE = 0.17) exhibited the best performance, while validation with an independent dataset (from a different growing period to those used in the model development) obtained NRMSE values of 0.25 and 0.24, respectively. The 4-waveband index provides enhanced performance and permits use of broader bandwidths than its 2-waveband counterpart. [ABSTRACT FROM AUTHOR]

Fly ash (FA) is promising for environmental remediation, but how to modify the FA with high remediation efficiency through an environmentally friendly and low-cost modification method is scare. A modified FA (MFA) was prepared through a one-step hydrothermal modification with Ca(OH)2 and KH2PO4. Results indicated that irregular agglomerates occurred on the surface of the MFA and that the specific surface area increased by 1.94 times compared to that of FA. Compared to FA, glassy compositions in MFA were destroyed and amorphous Si/Al and alkaline aluminosilicate gels were formed. The soil application of 0.2–0.6% MFA significantly increased soil pH by 0.23–0.86 units compared to FA and decreased available lead (Pb) and copper (Cu) by 25–97.1% and 13.5–75%, respectively. MFA significantly decreased exchangeable Pb and Cu by 12.5–32% and 11.4–35.2%, respectively, compared to FA. This may be due to the high pH and specific surface area of MFA, which promoted to the formation of amorphous Si/Al, metal–phosphate precipitation, and complexation with functional groups. In addition, MFA slightly increased the biomass of shoots and roots and decreased the uptake of Pb and Cu by ryegrass. This study provides a new modification method for the utilization of FA in the heavy metal-contaminated soils. [ABSTRACT FROM AUTHOR]

The efficient preservation of protein in silage for livestock feed is dependent on the rate and extent of proteolysis. Previous research on fresh forage indicated enhanced protein stability in certain Festulolium (ryegrass × fescue hybrids) cultivars compared to ryegrass. This is the first report of an experiment to test the hypothesis that a Lolium perenne × Festuca arundinacea var glaucescens cultivar had reduced proteolysis compared to perennial ryegrass (L. perenne) during the ensiling process. Forages were harvested in May (Cut 2) and August (Cut 4), wilted for 24 h and ensiled in laboratory‐scale silos. Silage was destructively sampled at 0 h, 9 h, 24 h, 48 h, 72 h, 14 days and 90 days post‐ensiling, and dry matter (DM), pH and chemical composition were determined. At Cut 2, there was no difference in crude protein between treatments but ryegrass had higher soluble nitrogen (SN) (P < 0.001) and grass × time interactions (p = 0.03) indicated higher rates of proteolysis. By Cut 4, Festulolium had (5.5% units) higher CP than ryegrass (p < 0.001) but SN did not differ. Ammonia‐N did not differ between silages in either cut. DM differences (11.8% units) between treatments in Cut 4 (v.2.2% in Cut 2) may have masked effects on proteolysis, highlighting the importance of management on silage quality. This was despite higher WSC in ryegrass in both cuts (p < 0.001), with grass × time interactions (Cut 2; p = 0.03) showing slower WSC decline in ryegrass in Cut 4 (p < 0.001). Silage pH values did not differ between grasses in either cut, but grass × time interactions (p < 0.001) showed a slower decline in both ryegrass cuts, resulting in higher (p < 0.05) pH at 24 h and 72 h for Cuts 2 and 4, respectively. Overall, the hypothesis for an enhanced protein stability in Festulolium when ensiled as ruminant feed was evidenced by lower SN but not ammonia‐N in an early‐cut silage with a comparable DM to ryegrass. An experiment tested the hypothesis that a Festulolium had reduced proteolysis compared to perennial ryegrass when ensiled. The benefits of Festulolium silage as ruminant feed were evidenced by lower soluble nitrogen but not ammonia‐N in an early‐cut silage with a comparable DM to ryegrass. [ABSTRACT FROM AUTHOR]

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]

Pasture seed samples that were harvested around 1917 in New Zealand were analysed for purity, Epichloë endophyte and insects. Samples consisted of 13 packets of seed varying from 2.2 to 15.0 g and comprising, Chewings fescue (Festuca rubra L.), cocksfoot (Dactylis glomerata L.), oat (Avena sativa L.), perennial ryegrass (Lolium perenne L.) and red clover (Trifolium pratense L.). These findings show that in the period prior to modern seed testing laboratories only four of the 13 samples (31%) could possibly have met today's seed certification standards as it relates to seed purity. When compared with published purities and weed content of seed of the era these samples appear typical. Endophyte testing on the four ryegrass seed samples and the ryegrass contaminants found in the Chewings fescue and cocksfoot samples showed sample-to-sample variation in endophyte infection from nil to 91%. One cocksfoot sample, most likely harvested from the Banks Peninsula, contained an Argentine stem weevil. Subsequent checking of entomological collection records also revealed specimens being present in the Wellington region from 1916. Together these occurrences precede the earliest published record for the species in New Zealand by ten years and suggest that it may have been widespread at that time. [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]

Benzoapyrene (B[a]P) pollution poses a threat to the environment and the food chain and consequently to human health. However, the alleviation of the harmful effects of B[a]P pollution in perennial ryegrass (Lolium perenne L.) by the application of exogenous nitric oxide (NO) has been ignored. Thus, in this paper the effects of exogenous sodium nitroprusside (SNP, a NO donor) on the growth, photosynthetic fluorescence characteristics, and antioxidant enzyme activity of ryegrass exposed to B[a]P stress are investigated. B[a]P stress induced the reduction of the aboveground and belowground dry weights, chlorophyll (a, b), the total chlorophyll contents, the carotenoid content, the net photosynthetic rate (Pn), the intercellular carbon dioxide concentration (Ci), the water use efficiency (WUE), the photosystem II (PSII) potential activity (Fv/F0), the maximum quantum yield of PSII photochemistry (Fv/Fm), the steady-state fluorescence yield (Fs), and the non-photochemical quenching (qN), while enhancement was recorded in response to the foliar spray of SNP at 200 and 300 μmol L-1 under B[a]P stress. Gray correlation and principal component analyses show that 200 μmol L-1 of SNP more drastically alleviated the damage caused by B[a]P stress than 300 μmol L-1 of SNP. The exogenous NO-mediated alleviation of B[a]P toxicity in ryegrass was associated with preserved photosynthetic characteristics and activation of antioxidant enzymes. [ABSTRACT FROM AUTHOR]

Background: Herbicide resistance is one of the threats to modern agriculture and its early detection is one of the most effective components for sustainable resistance management strategies. Many techniques have been used for target-site-resistance detection. Allele-Specific Loop-Mediated Isothermal Amplification (AS-LAMP) was evaluated as a possible rapid diagnostic method for acetyl-CoA carboxylase (ACCase) and acetolactate synthase (ALS) inhibiting herbicides resistance in Lolium spp. Results: AS-LAMP protocols were set up for the most frequent mutations responsible for herbicide resistance to ALS (positions 197, 376 and 574) and ACCase (positions 1781, 2041 and 2078) inhibitors in previously characterized and genotyped Lolium spp. populations. A validation step on new putative resistant populations gave the overview of a possible use of this tool for herbicide resistance diagnosis in Lolium spp. Regarding the ACCase inhibitor pinoxaden, in more than 65% of the analysed plants, the LAMP assay and genotyping were in keeping, whereas the results were not consistent when ALS inhibitors resistance was considered. Limitations on the use of this technique for herbicide resistance detection in the allogamous Lolium spp. are discussed. Conclusions: The LAMP method used for the detection of target-site resistance in weed species could be applicable with target genes that do not have high genetic variability, such as ACCase gene in Lolium spp. [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]

Aphids are major pests of cereal and pasture grasses throughout the world, vectoring disease and reducing plant production. There are few control options other than insecticides. Epichloë endophytes that produce loline alkaloids in their hosts provide a possible mechanism of control, with both meadow fescue and tall fescue naturally infected with loline-producing endophytes showing a resistance to Rhopalosiphum padi. We screened Elymus spp. naturally infected with endophytes that produced loline alkaloids at concentrations known to affect aphids on fescue but found no effect on these insects infesting Elymus. A synthetic loline-producing endophyte association with rye also had no effect on the aphids. After hypothesizing that the lolines were being translocated in the xylem in Elymus and rye rather than the phloem, we tested the rye and meadow fescue infected with loline-producing endophytes against a xylem feeding spittlebug. The endophyte in rye inhibited the feeding of the insect and reduced its survival, whereas the endophyte-infected meadow fescue had no effect on the spittlebug but reduced the number of aphids. Lolines applied to the potting medium of endophyte-free and endophyte-infected rye, ryegrass, and tall fescue resulted in a decrease in the aphid populations on the endophyte-free pasture grasses relative to the untreated controls but had no effect on aphid numbers on the rye. We tentatively conclude that lolines, produced in both natural and synthetic association with Elymus and rye, are partitioned in the xylem rather than the phloem, where they are inaccessible to aphids. [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]

[Display omitted] • Magnetic biochar and ryegrass can remediate heavy metal co-contaminated soils. • Magnetic biochar and ryegrass maintain the stability of soil organic carbon pool. • Magnetic biochar spheres can adsorb more Cr and Ni. • Biochar sustains ryegrass to fix heavy metals continuously. Biochar is a very promising material for soil remediation. However, most studies mainly focus on the adsorption ability of biochar on one heavy metal, which is difficult to evaluate the actual remediation effect since soils were contaminated with multiple heavy metals. In order to improve the soil remediation efficiency, we used the joint remediation method of magnetically modified biochar and ryegrass to remediate the soil polluted by compound heavy metals (chromium, nickel, copper, zinc, arsenic and cadmium), and evaluate the effect on the process of organic carbon mineralization in polluted soils. It was found that magnetic biochar and ryegrass together decreased the concentrations of Cr, Ni, Cu, Zn, As, and Cd in soils by 24.12 %, 23.30 %, 22.01 %, 9.98 %, 14.83 %, and 15.08 %, respectively, and reduced the available fractions. Ryegrass roots were the main accumulation part of heavy metals, and the order of enrichment effect was ranked as Zn > As > Cr > Cu > Ni > Cd. In addition, magnetic biochar can maintained the stability of the organic carbon pool, and inhibited the emission of volatile organic compounds from ryegrass. Overall, this study indicates that magnetic biochar spheres combined with ryegrass is an effective method for heavy metals co-contaminated soils, and has the excellent remediation ability for actual co-contaminated soils. [ABSTRACT FROM AUTHOR]

The temporal profile of methane (CH 4) emissions from ruminants is affected by feed composition and forage type. This study aimed to 1) describe and compare the post-feeding pattern of CH 4 emissions from lambs fed fresh ryegrass substituted with graded levels of forage rape, and 2) to evaluate the association between the magnitude of the variation in CH 4 emission patterns and organic fermentation products quantified in pre- and- post- feeding rumen content samples. Methane emissions were measured at approximately 6 min intervals in respiration chambers from 70 lambs (n = 14 per treatment) fed ryegrass only (FR0) or as a proportion, 0.25 forage rape + 0.75 ryegrass (FR25), 0.50 forage rape + 0.50 ryegrass (FR50), 0.75 forage rape + 0.25 ryegrass (FR75), and forage rape only (FR100). The magnitude of the variability in CH 4 emissions was defined as the ratio of maximum to minimum CH 4 emissions in a 24 h period. This ratio was correlated (P < 0.05) with the proportions of major short chain fatty acids, and calculated hydrogen (H 2) available per unit of glucose fermented (H 2 /GEF), quantified in rumen content samples collected pre- and- post- feeding. The CH 4 emission profile after each feeding followed an asymmetrical positively skewed shape for FR0 to FR75, but not in lambs fed FR100. The lowest CH 4 emission rates were observed before morning feeding which was followed by a CH 4 peak within the 2 h after feeding, and then the CH 4 emissions decreased until the next feeding. In FR100 lambs, the CH 4 emission rate was, unexpectedly, relatively constant after feeding, without any clear CH 4 peaks. The magnitude of the variability in the CH 4 emission rate increased when the pH of rumen contents and H 2 /GEF measured in pre-feeding samples decreased. Including forage rape at 0.75, or greater proportion, in the diet of lambs drastically changed the CH 4 emissions pattern, likely due to a continuous low pH in the rumen which is detrimental for methanogenesis. In conclusion, the daily variation in CH 4 emissions decreased with increasing forage rape inclusion in the diet of sheep and this was associated with a decreasing acetate proportion in the rumen liquid. • Lambs fed 100% forage rape had relatively constant CH 4 emissions throughout the day. • Adding increasing pasture to the forage rape increased the variability of CH 4. • H 2 available per unit of glucose fermented was correlated to the variability of CH 4. [ABSTRACT FROM AUTHOR]

Nematodes play an important role in agricultural soil in terms of their pest status and their contribution to soil quality, where they may serve as a valuable indicator of soil health. The aim of the study was to assess changes occurring in nematode community structure, as affected by soil tillage applied to high N-input and irrigated pastures in South Africa. Such practices were investigated by means of analysing diversity and ecosystem function indices, as well as the faunal profile, to enable analysis of their effect on soil quality. The pre-treatment soil analyses showed a low overall mean nematode density. No clear and predictable pattern was present in the nematode community structure in relation to tillage. The lack of indicative information leading from the nematode community structure to the tillage disturbance types might be linked to the fact that such systems were able to recover from soil disturbance within the relatively short period of less than a year. [ABSTRACT FROM AUTHOR]

Non‐crop plants such as grasses and volunteer plants are an inseparable part of the flora of crop fields and can influence virus incidence in crop plants. The presence of grasses as virus reservoirs can lead to a higher probability of virus incidence in crop plants. However, the role of reservoirs as an inoculum source in agricultural fields has not been well studied for many viral diseases of crops. Grasses have been found to constitute potential reservoirs for cereal‐infecting viruses in different parts of the world. This study revealed that cereal‐infecting viruses such as wheat dwarf virus (WDV), barley yellow dwarf viruses (BYDVs), and cereal yellow dwarf virus‐RPV (CYDV‐RPV) can be found among ryegrass growing in or around winter wheat fields. Phylogenetic analysis showed that a WDV isolate from ryegrass was a typical WDV‐E isolate that infects wheat. Similarly, a ryegrass isolate of barley yellow dwarf virus‐PAV (BYDV‐PAV) grouped in a clade together with other BYDV‐PAV isolates. Inoculation experiments under greenhouse conditions confirmed that annual ryegrass of various genotypes can be infected with WDV to a very low titre. Moreover, leafhoppers were able to acquire WDV from infected ryegrass plants, despite the low titre, and transmit the virus to wheat, resulting in symptoms. Information from the grass reservoir may contribute to improving strategies for controlling plant virus outbreaks in the field. Knowledge of the likely levels of virus in potential reservoir plants can be used to inform decisions on insect vector control strategies and may help to prevent virus disease outbreaks in the future. [ABSTRACT FROM AUTHOR]

SUMMARY: Loss of chlorophyll (Chl) is a hallmark of leaf senescence, which may be regulated by Chl catabolic genes, including NON‐YELLOW COLORING 1 (NYC1)‐like (NOL). The objective of this study was to determine molecular factors and metabolic pathways underlying NOL regulation of leaf senescence in perennial grass species. LpNOL was cloned from perennial ryegrass (Lolium perenne L.) and found to be highly expressed in senescent leaves. Transient overexpression of LpNOL accelerated leaf senescence and Chl b degradation in Nicotiana benthamiana. LpNOL RNA interference (NOLi) in perennial ryegrass not only significantly blocked Chl degradation in senescent leaves, but also delayed initiation and progression of leaf senescence. This study found that NOL, in addition to functioning as a Chl b reductase, could enact the functional stay‐green phenotype in perennial grass species, as manifested by increased photosynthetic activities in NOLi plants. Comparative transcriptomic analysis revealed that NOL‐mediated functional stay‐green in perennial ryegrass was mainly achieved through the modulation of Chl catabolism, light harvesting for photosynthesis, photorespiration, cytochrome respiration, carbohydrate catabolism, oxidative detoxification, and abscisic acid biosynthesis and signaling pathways. Significance Statement: Chlorophyll (Chl) degradation is a hallmark of leaf senescence. Here, we demonstrated that blocking a Chl catabolic gene, LpNOL, in perennial ryegrass results in functional stay‐green associated with metabolic modulation of Chl metabolism, light harvesting, photorespiration, cytochrome respiration, carbohydrate catabolism, oxidative detoxification, and abscisic acid biosynthesis and signaling to maintain the ability of photosynthesis and reactive oxygen species clearance, and metabolic energy supply, while inhibiting sugar accumulation. [ABSTRACT FROM AUTHOR]

Nutrient-use efficiency in pasture-crop rotations is not well understood. The hypothesis of this research is that nitrogen (N) cycled from the corn crop to the following pasture is not enough to supply the N demand of the pasture, independent of pasture height management. Our goal was to assess the carryover effect of N-fertilization from corn crop to a mixed pasture of black oat and ryegrass managed with two sward heights in an integrated crop-livestock system. The experimental design was a factorial arrangement (2 × 2) of sward height (10 and 25 cm) and N pasture fertilization: 0 kg N ha−1 (representing the carryover of N-fertilization from the corn crop) and 200 kg N ha−1. Accumulated forage dry matter and N concentration increased by 62% and 40%, respectively, in the pasture-fertilized compared with fertilization only in the previous crop phase. The residual effect of N applied to the previous corn crop was not enough to adequately meet the N requirements of the subsequent pasture, thereby reducing forage dry matter accumulation compared with the pasture-fertilized system. Our data suggest that fertilization of the pasture phase is key to better nutrient use efficiency in integrated crop-livestock systems. [ABSTRACT FROM AUTHOR]

A key challenge for autonomous precision weeding is to reliably and accurately detect weed plants and crop plants in real time to minimise damage to surrounding crop plants while performing weeding actions. Specifically for a wheat farm, classifying ryegrass weed plants is particularly difficult even with human eyes since ryegrass shows visually very similar shape and texture to the crop plants themselves. A Deep Neural Network (DNN) that exploits the geometric location of ryegrass is proposed for the real time segmentation of inter-row ryegrass weeds in a wheat field. Our proposed method introduces two subnets in a conventional encoder-decoder style DNN to improve segmentation accuracy. The two subnets treat inter-row and intra-row pixels differently, and provide corrections to preliminary segmentation results of the conventional encoder-decoder DNN. A dataset captured in a wheat farm by an agricultural robot at different time instances is used to evaluate the segmentation performance, and the proposed method performs the best among various popular semantic segmentation algorithms. The proposed method runs at 48.95 Frames Per Second (FPS) with a consumer level graphics processing unit, thus is real-time deployable at camera frame rate. • Deep neural network is proposed to segment inter-row ryegrass in a wheat field. • Dataset is captured by an agricultural robot with different wheat growth stages. • Method outperforms five state-of-the-art methods especially on detecting ryegrass. • Mean accuracy increases by 1.97%, 8.95% for pixel-wise, object-wise segmentation. • Proposed method runs in real-time at 48.95 FPS using a consumer level GPU. [ABSTRACT FROM AUTHOR]

Haloxylon ammodendron , a typical xerophyte, tolerates various abiotic stresses and is widely distributed in desert areas. Two PGPR strains, Bacillus sp. WM13-24 and Pseudomonas sp. M30-35, were previously isolated from the rhizosphere of H. ammodendron in Tengger Desert, Gansu province, northwest China. The aim of this study was to investigate the role of M30-35 and WM13-24 in drought stress alleviation of ryegrass (Lolium perenne L.). Under normal condition, both M30-35 and WM13-24 increased shoot fresh and dry weight, chlorophyll content, total nitrogen and phosphorus contents and altered phytohormone distribution compared to control. Moreover, after 7 days of drought stress, WM13–24 and M30-35 enhanced photosynthetic capacity, relative water content, the activities of catalase (CAT) and peroxidase (POD) and proline content, resulted in decreased malondialdehyde (MDA) content, relative membrane permeability (RMP) and H 2 O 2 accumulation; interestingly, the two strains decreased ABA content in leaves. This study demonstrated that the two PGPR strains promoted ryegrass growth and root development via regulating plant hormone distribution and enhanced drought tolerance of ryegrass through improving the activities of antioxidant enzymes, regulating ABA signaling and maintaining plant growth. Our results indicated that PGPR strains from rhizosphere of the desert plant species could be considered as promising bioinoculants for grass plants. • Both strains Bacillus sp. WM13-24 and Pseudomonas sp. M30-35 had plant growth promoting traits. • Both strains improved root system architecture and promoted the growth of ryegrass seedlings. • Both strains enhanced drought tolerance of ryegrass via enhancing antioxidant enzyme activities and regulating ABA signal. [ABSTRACT FROM AUTHOR]

Background: In view of the natural resistance of hemicelluloses in lignocellulosic biomass on bioconversion of cellulose into fermentable sugars, alkali extraction is considered as an effective method for gradually fractionating hemicelluloses and increasing the bioconversion efficiency of cellulose. In the present study, sequential alkaline extractions were performed on the delignified ryegrass material to achieve high bioconversion efficiency of cellulose and comprehensively investigated the structural features of hemicellulosic fractions for further applications. Results: Sequential alkaline extractions removed hemicelluloses from cellulose-rich substrates and degraded part of amorphous cellulose, reducing yields of cellulose-rich substrates from 73.0 to 27.7% and increasing crystallinity indexes from 31.7 to 41.0%. Alkaline extraction enhanced bioconversion of cellulose by removal of hemicelluloses and swelling of cellulose, increasing of enzymatic hydrolysis from 72.3 to 95.3%. In addition, alkaline extraction gradually fractionated hemicelluloses into six fractions, containing arabinoxylans as the main polysaccharides and part of β-glucans. Simultaneously, increasing of alkaline concentration degraded hemicellulosic polysaccharides, which resulted in a decreasing their molecular weights from 67,510 to 50,720 g/mol. Conclusions: The present study demonstrated that the sequential alkaline extraction conditions had significant effects on the enzymatic hydrolysis efficiency of cellulose and the investigation of the physicochemical properties of hemicellulose. Overall, the investigation the enzymatic hydrolysis efficiency of cellulose-rich substrates and the structural features of hemicelluloses from ryegrass will provide useful information for the efficient utilization of cellulose and hemicelluloses in biorefineries. [ABSTRACT FROM AUTHOR]

Lead (Pb), a highly toxic metal ion, is detrimental to plants and humans. Existing botanical techniques for Pbcontaminated soil remediation are limited in their efficiency. Here, we investigated the use of the fungus Trichoderma asperellum Samuels, Lieckf&Nirenberg SD-5, which we identified previously as being Pb-resistant, for phytoremediation and for its effects on plant growth, Pb adsorption, and physiological responses in perennial ryegrass (Lolium perenne L. 'Lark'). We set up four soil treatments: CK (uncontaminated by Pb), T1 (1000 mg kg-1 Pb), T2 (1:9 ratio of sawdust to T1), and T3 (T2 inoculated with T. asperellum SD-5). A pot experiment revealed that the addition of the Pb-resistant microorganism promoted growth and increased biomass in ryegrass under Pb stress, in addition to significantly enhancing photosynthesis by increasing the leaf chlorophyll content and improving the total protein content and expression of the pAPX, POD, SOD, and GPX genes, evidence of an improved antioxidant system and the alleviation of Pb stress. We demonstrated that Pb-resistant microorganisms can enhance Pb extraction from the soil, thus improving remediation. Mitigation mechanisms operating at the physiological and gene expression levels were also determined, providing a scientific basis for the role of combined plant-microorganism methods in remediating Pb-contaminated soil. [ABSTRACT FROM AUTHOR]

Lolium perenne L., a common plant perennial ryegrass from Europe, northern Africa and Asia, was selected to produce biomass under field conditions. The biomass of this nonfood crop was from a highly contaminated agricultural soil by potentially toxic metals (Cd, Pb and Zn) with the aim of maintaining the agricultural vocation of these soils. In this perspective and in view of the metal concentration (Cd, Pb, Zn, macro- and micro-nutrients), the biomass of ryegrass was considered as a bio 'ore' resource and was used as the starting material for the preparation of contemporary biosourced catalysts. The heterogeneous catalyst from the current work was successfully used in the synthesis of Moclobemide, used to treat anxiety and major depressive episodes. Through this original approach, Moclobemide was synthesized in one step, in 80% yield under solvent-free conditions. [ABSTRACT FROM AUTHOR]

The current study highlights the synthesis of Zn-enriched biosourced catalysts (BIOCATs) obtained from ryegrass (Lolium perenne L.) cultivated on contaminated soils located in the North of France (Noyelles-Godault and Auby, Hauts-de-France). These cultures were located on brownfield land, next to two former industrial sites where the zinc and lead metallurgists Metaleurop and Nyrstar were installed. Physical and morphological properties of BIOCATs were compared to heterogeneous catalysts (CATs) prepared from commercial zinc chloride and montmorillonite K10. The catalysts were thermally activated (120 °C, 280 °C or 500 °C). BIOCATs have been further compared to CATs and different commercial metal chlorides in terms of efficiency in the synthesis of anti-inflammatory agents, Piroxicam and Meloxicam, both of them being involved in the inhibition of cyclooxygenases (COX) and being the main ingredients of the Feldene® and Mobic® drugs, respectively. BIOCAT-assisted synthesis resulted in the best reaction yields (84% and 78%, respectively) among all the tested catalysts. The results indicated that ryegrass provides appropriate quantity of biomass and can be considered as a bio-ore resource to improve green metrics in an environmental context involving clean and green technologies. Furthermore, the Zn/Cd and Zn/Pb ratios obtained in the ashes of ryegrass shoots were in general comprised between 153 and 202. This result demonstrated the excellent selectivity of ryegrass for zinc at the expense of the more problematic Cd and Pb, which are carcinogenic, mutagenic and reprotoxic. Future efforts are now needed to use BIOCATs in the synthesis of other high value-added molecules. [Display omitted] [ABSTRACT FROM AUTHOR]

The indiscriminate use of sulfadiazine has caused severe harm to the environment, and biodegradation is a viable method for the removal of sulfadiazine. However, there are few studies that consider sulfadiazine biodegradation mechanisms. To comprehensively investigate the process of sulfadiazine biodegradation by plants in a soil system, a potted system that included ryegrass and soil was constructed in this study. The removal of sulfadiazine from the system was found to be greater than 95% by determining the sulfadiazine residue. During the sulfadiazine removal process, a significant decrease in ryegrass growth and a significant increase in antioxidant enzyme activity were observed, which indicates the toxic response and detoxification mechanism of sulfadiazine on ryegrass. The ryegrass transcriptome and soil bacterial communities were further investigated. These results revealed that most of the differentially expressed genes (DEGs) were enriched in the CYP450 enzyme family and phenylpropanoid biosynthesis pathway after sulfadiazine exposure. The expression of these genes was significantly upregulated. Sulfadiazine significantly increased the abundance of Vicinamibacteraceae , RB41 , Ramlibacter, and Microvirga in the soil. These key genes and bacteria play an important role in sulfadiazine biodegradation. Through network analysis of the relationship between the DEGs and soil bacteria, it was found that many soil bacteria promote the expression of plant metabolic genes. This mutual promotion enhanced the sulfadiazine biodegradation in the soil system. This study demonstrated that this pot system could substantially remove sulfadiazine and elucidated the biodegradation mechanism through changes in plants and soil bacteria. [Display omitted] • Sulfadiazine caused severe phytotoxicity and induced oxidative stress in ryegrass. • Ryegrass has mobilized metabolic genes involved in sulfadiazine biodegradation. • Key bacteria in soil are essential for sulfadiazine biodegradation. • This study combined plant and soil processes for biodegradation of sulfadiazine. [ABSTRACT FROM AUTHOR]

Silicon (Si) has the potential to promote plant yield and improve their insect resistance, but the direct defense mechanisms associated with the effects of Si on forage grasses and its regulation are not known. In this study, the conditions of silica fertilization nutrition (1 and 3 mmol L−1 recorded as low concentration (LC) and high concentration (HC) groups, respectively) were changed during the seed germination period, which did not significantly affect the seed germination of ryegrass. However, the shoot biomass and insect resistance of ryegrass were significantly increased in the HC group. Comparison of the transcriptional results from RNA-seq assays revealed that the accumulation of ryegrass biomass may be closely related to the silicon intervention in photosynthesis, and the metabolic synthesis of lignin, carbohydrates, and hemicellulose. There was an additive effect of silicon concentration on the regulatory effects of ryegrass at the transcriptional level. Meanwhile, 98 and 1291 differentially expressed genes were assigned to the metabolic process in the LC and HC groups, respectively. Metabolomic results combined with LC-MS analysis showed that Si initiated a direct defense network in ryegrass with Phenylpropanoid biosynthesis as the backbone, and Flavonoid, Flavone and flavonol, and Isoflavonoid biosynthesis as important branches. The relative content of phenolics was significantly up-regulated, especially in the HC group, and most of these phenolics were potent SOS substances, closely related to the physiological disturbances suffered by Spodoptera frugiperda , with inhibitory effects on larval body weight. The above results confirm that silicon promotes an increase in ryegrass yield while initiating its direct defense network against insects, and that silicon is an effective supplement in improving ryegrass yield and insect resistance. [Display omitted] • Silicon treatment increased the shoot biological production of ryegrass. • Silicon treatment initiated the direct defense network of ryegrass. • Silicon treatment significantly up-regulated the phenolic content in ryegrass. • Silicon treatment improved insect resistance in ryegrass. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate nutrient digestibility, nitrogen balance, and purine derivative excretion from growing sheep fed on ryegrass silage (S) or ryegrass hay (H) cut at two maturity stages (21 and 35 d). In an in vivo trial, 32 Suffolk × Merino growing sheep (22 ± 2 kg) were used in a completely randomised design with eighth replications in a 2 × 2 factorial arrangement. Four diets were used containing 75% forage (S at 21 or 35 d and H at 21 or 35 d) and 25% concentrate. In an in vitro trial, a completely randomised design was used for gas production parameters. Contents of N and NDF were higher in H (30 and 674 g/kg DM) than in S (26 and 411 g/kg DM). Animals fed on S had higher digestibility (P <.008) of DM and OM (661 and 715 g/kg) than H at 35 d (557 and 596 g/kg). In vitro gas production was lower (P <.04) in H at 35 d. In vitro DM disappearance at 96 h was lower (P <.03) for H at 35 d. Excretion of allantoin (mmol/day) in urine was higher (P <.001) in S (7.91 and 3.95) than H (5.01 and 3.03) at 21 and 35 d respectively. Overall, compared to ryegrass hay, ryegrass silage cut at 21 d can be an advantageous feeding strategy for growing sheep without negative effects in nutrient intake, N-balance, and purine derivatives. Contents of N and NDF were higher in hay than in silage form ryegrass. Animals fed on silage had higher digestibility of DM and OM. In vitro gas production was lower in hay cut at 35 days. [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]

We tested whether selection of ryegrass for reduced root hair length and density would reduce root competition on white clover for phosphate (P). A Rhizosheath Selection Tool was used to select two ryegrass populations with contrasting root hair traits. These were grown at five soil P levels in a glasshouse experiment and rhizosheath trait selection had no effect on growth or shoot P concentrations. The ryegrass populations were also grown with white clover in soils with Olsen P12 or 19 mg L−1. In the Olsen P12 soil, clover grown with the smaller rhizosheath ryegrass had significantly heavier shoots and contained more P than clover grown with the larger rhizosheath ryegrass. In the Olsen P19 soil differences in ryegrass rhizosheath had no effect on clover growth. The results showed that under the experimental conditions, grass-clover competition for soil P could be modified by the rhizosheath traits of ryegrass. [ABSTRACT FROM AUTHOR]

Ryegrass is the primary pasture crop in New Zealand; however, despite this importance, gains in yield through conventional breeding have been marginal. Other significant crops, particularly maize and rice, have benefited from hybrid breeding programmes whereby heterosis has been exploited. Ryegrass presents many challenges to breeders wishing to produce F1 hybrid progeny on a large scale such as self-incompatibility, inbreeding depression, and a lack of genetic tools for creating and maintaining male-sterile lines for crossing. Many of these challenges have been overcome in other species, providing a basis for addressing them in ryegrass. With the advent of new technologies such as CRISPR gene editing and the genome sequence for ryegrass, F1 hybrid production is now possible on a large scale. Regulations in New Zealand surrounding new genetic tools are a hurdle which must be addressed to allow the agricultural industry in New Zealand to apply these advanced technologies. [ABSTRACT FROM AUTHOR]

In this work, the thermally modified attapulgite was prepared by high temperature modification and analyzed by scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and specific surface area test (BET). The results showed that the crystal phase structure of the thermally modified attapulgite was not changed compared with the attapulgite, but the content of the adsorption water and zeolite water was reduced, the surface crystal bundle structure was more obvious and the specific surface increased. The adsorption capacity of attapulgite to Cd could be improved after thermal modification, and the adsorption mechanism was mainly through the coordination of hydroxyl and silica hydroxyl with Cd. Added different doses of thermally modified attapulgite combined with ryegrass to remediate low and high concentrations of Cd-contaminated soil showed that the thermally modified attapulgite could reduce the longitudinal migration of Cd in the soil layer and the risk of groundwater pollution, but increase the biomass of ryegrass and lower the concentration of Cd in the shoot of ryegrass. It could significantly improve the total Cd extracted from the ryegrass both in the low and high contamination pollution soils when the thermally modified attapulgite dosage were 20 g·kg−1. The mechanism of the thermally modified attapulgite combined with ryegrass was mainly increased the soil pH and surface adsorption of Cd by thermally modified attapulgite, thereby reduced the content of exchangeable Cd in soil, improved the activity of urease and catalase in the soil and the diversity of soil microflora, so as to reduced the malondialdehyde (MAD) content in ryegrass and the stress of Cd on ryegrass, increased ryegrass biomass. Added thermally modified attapulgite could effectively solve the problem that ryegrass could not grow normally in soil with high pollution of Cd. And the total amount of Cd extracted from ryegrass increased by increasing the biomass of ryegrass per unit area. [ABSTRACT FROM AUTHOR]

In order to examine the ecological effects of planting grass in kiwifruit orchards in Shiyan, Hubei Province, we selected two kiwifruit orchards located in Changpingtang and Gaoling villages as study sites. We assessed the effects of two grass planting methods, namely, artificial and natural grass planting, and selected white clover and ryegrass as artificial grass types. The effects of artificial and natural grass planting on soil nutrients, weed species and quantity, and fruit yield and quality were compared and analyzed. The results showed that compared with natural grass planting, artificial grass planting could effectively reduce the number and quantity of weed species, particularly in response to planting white clover. It also increased the contents of soil organic matter, alkali-hydrolyzed nitrogen, available phosphorus, and available potassium in the two kiwifruit orchards, and reduced the pH value of alkaline soil. Furthermore, of the two artificial grass types assessed, ryegrass was found to have a better effect on reducing soil pH than white clover. However, neither of the grass planting methods had a significant effect with respect to improving soil temperature, or fruit yield and quality, although artificial grass planting was found to significantly increase soil humidity in the Gaoling kiwifruit orchard（P<0.05）. With an extension of planting time, planting ryegrass clearly increased the contents of soil alkali-hydrolyzed nitrogen, available phosphorus, and available potassium. The findings of this study revealed that compared with planting natural grass and white clover, planting ryegrass was more suitable for kiwifruit orchards in Shiyan, Hubei Province. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the effects of diet with different proportions of ryegrass on breast meat quality of geese. In total, 240 healthy male Yangzhou geese (28-day-old) with similar body weight were divided randomly into 4 diet groups (control group: fed commercial diets; treatment groups I, II, and III: fed ryegrass and commercial diet in the ratios of 1.5:1, 2:1, and 3:1, respectively), the birds being fed from the age of 29 to 70 D. The results shows that the body weights of 70-day-old geese of treatment groups II and III were lower than those in the control group, whereas those of geese of treatment group I were similar to those of the control group. The contents of flavor amino acid and total (essential) amino acids in treatment groups I and II were higher than those in treatment group III (P, 0.05). In addition, grass supplementation reduced saturated fatty acid content and increased that of omega-3 (n-3) polyunsaturated fatty acids, relative to the control group (P, 0.05). Finally, among the 6 minerals analyzed in breast muscle, differences existed in Zn, Se, and Cu contents among the geese fed with different proportions of ryegrass. Zn content of geese from treatment groups II and III was significantly higher than that of those of the control group; Cu content was lower with grass intake and was significantly higher in the control group than in treatment group III; Se content was significantly higher in the control group than in both groups II and III (all at P, 0.05). The results from this study indicated that geese fed with low proportions of ryegrass (1.5:1 or 2:1) showed good growth performance and increased total (essential) amino acid, flavor amino acid, n-3 polyunsaturated fatty acid, and Zn content in meat, which had a certain guiding value for the production of highquality goose meat under intensive feeding conditions. [ABSTRACT FROM AUTHOR]

Forage nutritive value impacts animal nutrition, which underpins livestock productivity, reproduction and health. Genetic improvement for nutritive traits in perennial ryegrass has been limited, as they are typically expensive and time-consuming to measure through conventional methods. Genomic selection is appropriate for such complex and expensive traits, enabling cost-effective prediction of breeding values using genome-wide markers. The aims of the present study were to assess the potential of genomic selection for a range of nutritive traits in a multi-population training set, and to quantify contributions of family, location and family-by-location variance components to trait variation and heritability for nutritive traits. The training set consisted of a total of 517 half-sibling (half-sib) families, from five advanced breeding populations, evaluated in two distinct New Zealand grazing environments. Autumn-harvested samples were analyzed for 18 nutritive traits and maternal parents of the half-sib families were genotyped using genotyping-by-sequencing. Significant (P, 0.05) family variance was detected for all nutritive traits and genomic heritability (h2 g) was moderate to high (0.20 to 0.74). Family-by-location interactions were significant and particularly large for water soluble carbohydrate (WSC), crude fat, phosphorus (P) and crude protein. GBLUP, KGD-GBLUP and BayesCp genomic prediction models displayed similar predictive ability, estimated by 10-fold cross validation, for all nutritive traits with values ranging from r = 0.16 to 0.45 using phenotypes from across two locations. High predictive ability was observed for the mineral traits sulfur (0.44), sodium (0.45) and magnesium (0.45) and the lowest values were observed for P (0.16), digestibility (0.22) and high molecular weight WSC (0.23). Predictive ability estimates for most nutritive traits were retained when marker number was reduced from one million to as few as 50,000. The moderate to high predictive abilities observed suggests implementation of genomic selection is feasible for most of the nutritive traits examined. [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]

The bioeconomy, with its aim of replacing fossil by biobased resources, is increasingly focusing on biomass production from perennial crops, such as miscanthus. To date, research on miscanthus has explored a number of cultivation aspects; however, one major issue has not yet been addressed: How can former miscanthus fields be reintegrated into a crop rotation? This encompasses the questions of which following crop most efficiently suppresses resprouting miscanthus and what happens to the soil nitrogen content after a miscanthus removal. This study aimed to answer both questions. For this purpose, four spring crops (ryegrass, rapeseed, barley, maize) and fallow as control were cultivated after a Miscanthus sinensis removal. To test the effect of the removal on soil nitrogen content, each spring crop (excluding fallow) was divided into fertilized and unfertilized plots. After the spring crop harvest, winter wheat was cultivated to clarify which spring crop had most efficiently suppressed the resprouting miscanthus. The results indicate that fertilized crops had 35% less miscanthus biomass per hectare than unfertilized crops, probably due to the higher plant density and/or better development of the fertilized crops during the growing season. The soil mineral nitrogen (Nmin) content was found to increase during the vegetation period following the miscanthus removal (average +14.85 kg/ha), but was generally on a low level. We conclude that nitrogen from miscanthus residues is partly fixed in organic matter and is thus not plant‐available in the first cropping season. As some nitrogen is supplied by the decomposition of miscanthus residues, our results suggest that the crop cultivated after a miscanthus removal requires less fertilization. Of all the follow‐on spring crops tested, maize coped with the prevailing soil conditions and resprouting miscanthus most efficiently, resulting in satisfactory yields, and thus seems to be a suitable crop for cultivation after miscanthus. [ABSTRACT FROM AUTHOR]

Atrazine (ATR) continues being one of the most frequently detected pesticides in natural waters and soils. In this work, an electrokinetic-assisted phytoremediation pot test (EKPR) was performed for the remediation of an atrazine-spiked soil; a low electric voltage gradient (1 V cm−1) with two different electric field operation times (6 and 24 h per day) was used in combination with ryegrass (Lolium perenne L.). EKPR increased up to 27% and 7% the overall ATR removal from soil as compared to natural attenuation and phytoremediation treatments, respectively. ATR soil concentration vs time curves were fitted to a pseudofirst-order kinetic equation, obtaining ATR half-life values of 8.2, 7.1 and 5.4 days for the treatments corresponding, respectively, to 0, 6 and 24 h day−1 of electric current application. It clearly showed that the ATR removal from soils was enhanced by the electric field. ATR plant accumulation was significantly improved with respect to phytoremediation when the electric current was continuously applied throughout the experiment (24 h day−1); most of the ATR residues were accumulated in the shoot biomass of the ryegrass plants. Image 1 • Application of EKPR increased up to 27% and 7% as compared to natural attenuation and phytoremediation treatments. • 11–21% of the initial atrazine was accumulated in the ryegrass tissues. • Approximately 80% of the atrazine was removed in the first 4 days of treatment. [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]

Although studies on immobilized microorganisms have been conducted, their performance remains unclear for enhancing plants to remediate cadmium (Cd)-contaminated soil. In this study, a Cd-resistant strain TY-1 with good plant growth promotion traits was immobilized by biochar (BC) or oyster shell (OS) power to strengthen ryegrass to remediate Cd-contaminated soil. SEM-EDS combined with FTIR showed that TY-1 could tolerate Cd toxicity by surface precipitation, and functional groups such as hydroxyl and carbonyl groups might be involved. In the biocomposite treatments, soil pH increased, and the activity of fertility-related enzymes such as dehydrogenase increased by 109.01%–128.01%. The relative abundance of genus Saccharimonadales decreased from 7.97% to 3.35% in BS-TY and 2.61% in OS-TY, respectively. Thus, a suitable environment for ryegrass growth was created. The fresh weight, dry weight, plant height and Cd accumulation of ryegrass in TY treatment increased by 122.92%, 114.81%, 42.08% and 8.05%, respectively, compared to the control. Cd concentration in ryegrass was further increased in BC-TY and OS-TY by 24.14% and 40.23%, respectively. The improvement in soil microcosm and plant biomass forms an ongoing virtuous cycle, demonstrating that using carrier materials to improve the efficiency of microbial-assisted phytoremediation is realistic and feasible. [Display omitted] • A bacterial strain with both Cd resistance and plant-promoting traits was isolated. • Multiple functional groups were involved in Cd resistance and cell immobilization. • The biocomposites significantly improved soil microhabitat and ryegrass growth. • Immobilized strain TY-1 significantly enhanced Cd uptake by ryegrass. [ABSTRACT FROM AUTHOR]

Microplastics pollution in environments has become a major concern and it has been proven to have adverse impacts on plants, so there is an urgent to find approaches to alleviate the detrimental effects of microplastics. In our study, we investigated the influence of polystyrene microplastics (PSMPs) on the growth, photosynthesis, and oxidative defense system changes of ryegrass, as well as the behavior of MPs at roots. Then three types of nanomaterials were applied to alleviate the adverse impact of PSMPs on ryegrass, which were nano zero-valent iron (nZVI), carboxymethylcellulose-modified-nZVI (C-nZVI) and sulfidated nZVI (S-nZVI), respectively. Our results suggested that PSMPs had significant toxicity to ryegrass, leading to decrease of shoot weight, shoot length and root length. Three nanomaterials regained the weight of ryegrass to a varying extent and made more PSMPs aggregate near roots. In addition, C-nZVI and S-nZVI facilitated the entrance of PSMPs into the root and promoted the chlorophyll a and chlorophyll b contents in leaves. Analysis of antioxidant enzymes and malondialdehyde content indicated that ryegrass coped well with the internalization of PSMPs, and all three types of nZVI could alleviate PSMPs-stress in ryegrass. This study elaborates the toxicity of MPs on plants and provides a novel insight into the fixing of MPs by plants and nanomaterials in environments, which needs to be further explored in future research. [Display omitted] • PSMPs decreased biomass, length and photosynthetic pigments of plants. • Three types of nZVI all alleviated the toxicity of PSMPs. • Three types of nZVI all promoted plant growth under exposure of PSMPs. • C-nZVI and S-nZVI facilitated the internalization of PSMPs. • S-nZVI might have a more alleviation on the oxidative stress when exposed to PSMPs. [ABSTRACT FROM AUTHOR]