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Urban grasslands span climates and topography in soils with variable water infiltration and drainage rates that result in occasional waterlogging stress, while data on grass species tolerance to waterlogging stress is scant. Whole plant responses to waterlogging stress among cool‐season grass species were quantified in a controlled environment. The following grasses were grown in well‐drained vs. waterlogged soil for 55 d: strong creeping red fescue (Festuca rubra ssp. rubra), slender creeping red fescue (F. rubra ssp. littoralis), Chewings fescue (F. rubra ssp. commutata), hard fescue (F. brevipila), tall fescue (F. arundinacea syn. Schedonorus arundinaceus), Kentucky bluegrasses (Poa pratensis), annual bluegrass (P. annua), rough bluegrass (P. trivialis), creeping bentgrass (Agrostis stolonifera), perennial ryegrass (Lolium perenne), and alkaligrass (Puccinellia distans). Five cultivars of each fine fescue (Festuca spp.) taxon were included for comparison. When grown in waterlogged soil compared to well‐drained conditions, relative differences generally ranged from −3% to −26% (shoots) and −13% to −33% (roots) for creeping bentgrass, tall fescue, and Kentucky bluegrass indicating higher waterlogging stress tolerance. The relative differences ranged from −18% to −43% in shoots and −3% to −34% in roots for annual bluegrass and perennial ryegrass indicating fair performance under waterlogging stress. Fine fescues, rough bluegrass, and alkaligrass exhibited the poorest performance during waterlogging stress with plant responses ranging from −12% to −64% (shoots) and −17% to −73% (roots). Negative whole plant responses among cultivars of four fine fescue taxa were similar. The selection of grasses tolerant to waterlogging stress will be important in developing resilient landscapes. [ABSTRACT FROM AUTHOR]

The present experiment was undertaken to characterize the K releasing pattern as well as the bioavailability of K in nine soils under three dominant soil orders of eastern India. Soils were extracted with 0.2 M sodium tetraphenyl boron (NaTPB) and perennial ryegrass (Lolium perenne L.) was grown repeatedly with and without the addition of K fertilizer to study the K release kinetics and bioavailability. The highest K release by 0.2 M NaTPB at 144 h incubation was recorded in Entisols, while the least in Alfisols. Cumulative K released was mathematically best described by a parabolic diffusion equation and the empirical constants up to a 2 h incubation period was significantly related to relative biomass yield and K uptake by ryegrass. Considering relative biomass yield and K uptake as indices of plant K availability, the sequence of K supplying capacity of the soils under different orders was: Entisols>Inceptisols>Alfisols. The K-release rate of 30.8 mg kg-1 h-1 and the ryegrass leaf K concentration of 32.1 g kg-1 were found to be critical for this experiment. Based on the critical K release rate, the maximum amount of K released for plant uptake before showing any K deficiency symptom ranged from 179.3 mg kg-1 to 596 mg kg-1 for soils under the order Entisols, 247.9 mg kg-1 to 687.84 mg kg-1 for soils under Inceptisols and 118.67 mg kg-1 to 184.25 mg kg-1 for soils under Alfisols. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENT\nHIGHLIGHTSIn recent years, heavy metal pollution has become a global environmental problem and poses a great threat to the health of people and ecosystems. Therefore, strategies for the effective remediation of Cd from contaminated soil are urgently needed. In this study, ryegrass was utilized as a remediation plant, and its remediation potential was enhanced through the application of Citric Acid (CA) in conjunction with Bacillus megaterium (B. megaterium). The P3 treatment (CA + Bacillus megaterium) exhibited a significantly higher efficiency in promoting cadmium extraction by ryegrass, resulting in a 1.79-fold increase in shoot cadmium accumulation compared to the control group (CK) with no Bacillus megaterium or CA. Moreover, the P3 treatment led to an increased abundance of Actinobacteriota, Acidobacteriota, and Patescibacteria in the rhizosphere. The concentration of amino derivatives (such as betaine, sulfolithocholylglycine, N-alpha-acetyl-lysine, glycocholic acid, arginyl-threonine) showed significant upregulation following the P3 treatment. In summary, this study proposes a viable approach for phytoremediation of soil contaminated with cadmium by harnessing the mobilizing abilities of soil bacteria.Our aim was to gain a comprehensive understanding of the mechanisms involved in phytoremediation. These findings contribute to the existing knowledge by providing insights into the mechanism of phytoremediation in Cd-contaminated soil. They are expected to serve as a theoretical foundation for further elucidation of the phytoremediation mechanisms employed in Cd-contaminated soil.CA + Bacillus megaterium increased Cd accumulation in ryegrass by 1.79 times compared to CK.CA + Bacillus megaterium also significantly improved the activity of soil enzymes.CA + Bacillus megaterium significantly improved soil bacterial communities.CA + Bacillus megaterium significantly increased metabolites in the soil. [ABSTRACT FROM AUTHOR]

Breeding ryegrass for reduced inorganic phosphorus (Pi) concentrations in leaf vacuoles could lower pasture P fertiliser requirements with economic and environmental benefits. We investigated foliar Pi% accumulation characteristics of a range of ryegrass cultivars and ecotypes in glasshouse experiments, and ryegrass cultivars from two field trials. Pi in ryegrass was also compared with Pi in cocksfoot, tall fescue, prairie grass and Phalaris in a glasshouse experiment. Pi expressed as a percentage of leaf total phosphorus was higher (average 82.5%) in the older ryegrass cultivars – Ruanui, and Nui and the New Zealand hill country ecotypes (85%) than in more recently bred cultivars like Aberdart and One50 (74.7%). In the other grass species, foliar Pi% was lowest in prairie grass, intermediate in tall fescue with the highest values in cocksfoot, Phalaris and ryegrass. The results suggest that including a lower Pi concentration in future ryegrass breeding programmes might improve ryegrass P use efficiency without compromising growth rates. [ABSTRACT FROM AUTHOR]

Failure of perennial ryegrass‐based pastures to persist beyond 3 years post‐sowing is an increasing threat to the sustainability of livestock industries in the north of New Zealand. Little is known of the long‐term responses of plants and populations to the environmental stresses responsible for persistence failure, or the effects of ryegrass genetics on those responses. Plants were collected from 10‐year‐old pastures sown in two environments (Waikato, North Island: warm‐temperate, summer/autumn dry; Canterbury, South Island: cool temperate, irrigated) to four ryegrass functional types and grazed by dairy cattle. Surviving plants in Canterbury pastures were almost all true‐to‐type for the original genotype, whereas there was substantial ingress of volunteer plants in the diploid cultivars in Waikato. Plants confirmed as true‐to‐type were compared to reference plants grown from the original seed lines. Leaf mass was lower in survivor plants than in reference plants for all functional types. This effect was reversed by recruitment of new plants from seed in a grazing deferment treatment applied at the Waikato site 18 months before plant collection, in a manner consistent with epigenetic control. Reproductive development was delayed by 4–6 days in survivors of mid‐ and late flowering diploid cultivars: this effect appeared to be the result of true genetic differentiation. There was less aftermath heading in the Canterbury survivors, but not Waikato survivors, compared with the reference plants. The relevance of these findings for ryegrass survival strategies and targeted selection of traits for improved persistence is discussed. [ABSTRACT FROM AUTHOR]

Aims This study aimed to compare the effects of linear and branched fructooligosaccharides (FOS) extracted from chicory and grass (Lolium perenne), respectively on human microbiota composition, diversity, and metabolism. Methods and results To test the effects of linear and branched FOS on human microbiota we used the artificial in vitro human colon model (TIM-2). Microbiota composition and diversity were assessed by V3–V4 16S rRNA metagenomic sequencing, followed by differential taxa abundance and alpha/beta diversity analyses. SCFA/BCFA production was evaluated by gas chromatography–mass spectrometry. As a result, branched FOS had the most beneficial effects on microbial diversity and metabolite production. Also, branched FOS significantly increased the abundance of commensal bacteria associated with maintaining healthy gut functions and controlling inflammation, such as Butyricicoccus, Erysipelotrichaceae, Phascolarctobacterium , and Sutterella. Linear FOS also significantly increased the abundance of some other commensal gut bacteria (Anaerobutyricum, Lachnospiraceae, Faecalibacterium), but there were no differences in diversity metrics compared to the control. Conclusions The study revealed that branched FOS had the most beneficial effects compared to the linear FOS in vitro , concerning microbiota modulation, and metabolite production, making this a good candidate for further studies in food biotechnology. [ABSTRACT FROM AUTHOR]

Brown patch (caused by various Rhizoctonia and Rhizoctonia‐like species) is a major summer disease for several cool‐season turfgrass species, including creeping bentgrass (CBG) (Agrostis stolonifera L.), colonial bentgrass (CLBG) (Agrostis capillaris L.), perennial ryegrass (PRG) (Lolium perenne L.), and turf‐type tall fescue (TTTF; [Schedonorus arundinaceus (Schreb.) Dumort., nom. cons.]). Elevated nitrogen (N) rates are suggested to enhance development of brown patch symptoms. A controlled environment study was conducted to determine the influence of two N rates among four cool‐season turfgrass species maintained at 1.9 cm after inoculation with R. solani. Field‐grown plants of four CBG cultivars, a CLBG cultivar, a PRG blend, and two TTTF cultivars were fertilized weekly, totaling 49 and 196 kg N ha−1 across four applications. Turfgrass responses were measured as relative growth rate, brown patch severity, and seasonal brown patch using area under the disease progress curve (AUDPC). On average, peak brown patch severity among the species and cultivars was between 22.6% and 68.1% for Raptor III TTTF and Penn A‐1 CBG, respectively. Turf‐type tall fescue cultivars decreased brown patch by 61% compared to CBG, CLBG, and PRG. The lower N rate reduced brown patch AUDPC by 17% and 33% for CBG and PRG, respectively, but N rate generally had no effect for CLBG and TTTF. These results reinforce the importance of planting disease‐resistant species and cultivars. Additionally, N rate may be an important factor affecting brown patch severity for select intensively managed turfgrass species. Core Ideas: Among the four cool‐season turfgrass species studied, tall fescue was the most resistant to brown patch.Brown patch‐resistant cultivars had significantly less disease compared to susceptible cultivars.Increased nitrogen rates were associated with enhanced brown patch in creeping bentgrass and perennial ryegrass.Nitrogen rate did not influence brown patch severity on the colonial bentgrass and tall fescue. [ABSTRACT FROM AUTHOR]

Context: Data are lacking on the effects of selected endophytes of perennial ryegrass (Lolium perenne L.) on ryegrass persistence. Aim: We aimed to determine the impact of Epichloë endophyte on the persistence of mid- and late-heading perennial ryegrass cultivars. Method: Two mid-heading (Samson, Bronsyn) and two late-heading (One50, Rohan) cultivars, infected with selected endophytes (AR37, nea2/6) or with standard toxic endophyte, were established in a replicated plot study grazed by cattle in a subtropical environment of the upper North Island of New Zealand. Persistence characteristics were quantified at least five times per annum, over 4 years. Key results: Endophyte strain had an effect on persistence; infection with standard endophyte resulted in higher ryegrass ground cover percentage, ryegrass content in pasture dry matter and autumn yield than infection with nea2/6 on many occasions, and with AR37 on some occasions. There were negligible impacts on ryegrass tiller density or nutritive value. Trends were dominated by the main effect of endophyte; interactions with heading date were inconsistent. Conclusions: Cultivars were more persistent when infected with standard endophyte than with selected endophytes, although persistence declined over 4 years for all cultivars and irrespective of heading date. Implications: Reliance on selected endophyte is unlikely to prevent persistence decline of perennial ryegrass in a subtropical environment. Other strategies will be required to maintain the persistence of high-quality pastures based on perennial ryegrass. We determined the impact of endophyte strain (standard toxic endophyte, selected strains nea2/6 and AR37), on the persistence of four perennial ryegrass cultivars. Standard endophyte resulted in greater persistence than the selected endophytes, with higher ryegrass ground cover percentage and content in pasture dry matter by the end of the study, and higher herbage yields in autumn. Persistence declined over 4 years for all cultivars, regardless of endophyte. [ABSTRACT FROM AUTHOR]

Context: Data are lacking on the effects of heading date of perennial ryegrass (Lolium perenne L.) on ryegrass persistence. Aim: We aimed to determine the impact of heading date on perennial ryegrass persistence. Method: Two mid-heading (Samson, Bronsyn) and two late-heading (One50, Rohan) cultivars, infected with Epichloë endophytes (AR37, nea2/6 or standard toxic), were established in a replicated plot study grazed by cattle in a subtropical environment of the upper North Island of New Zealand. Persistence characteristics were quantified at least five times per annum, over 4 years. Key results: Late-heading cultivars had higher yield, nutritive value, perennial ryegrass content in pasture dry matter, ground cover and tiller density than mid-heading cultivars. There were large seasonal impacts on all ryegrass characteristics, with a major decline over summer and recovery during late autumn into early spring, with less recovery in the final year. Overall, there was a strong linear decline in ryegrass content measured during spring (2018–21). Conclusions: The two late-heading cultivars were more persistent than the two mid-heading cultivars, although persistence declined over 4 years for all cultivars. Implications: Results support industry recommendations of choosing late-heading cultivars for improved pasture quality and persistence. We determined the impact of heading date on persistence of perennial ryegrass cultivars infected with a range of endophytes, in a plot study grazed by cattle. The two late-heading cultivars were more persistent than the two mid-heading cultivars, with higher yield, nutritive value, perennial ryegrass content in pasture dry matter, ground cover and tiller density, although persistence declined over 4 years for all cultivars. [ABSTRACT FROM AUTHOR]

Herbicide promotes physiological and biochemical changes even in tolerant species. The objective of this study was to evaluate the interference of the herbicides clodinafop-propargyl and 2,4-D in the antioxidant system of wheat, and iodosulfuron-methyl in wheat and ryegrass. Two studies, divided into three experiments, were conducted in an entirely randomized design in a greenhouse and phytotron. The first study tested herbicides iodosulfuron-methyl, clodinafop-propargyl, 2,4-D, and a control without application in wheat. The second, divided into two experiments with wheat and ryegrass, tested iodosulfuron-methyl doses (0, 1.75, 3.5, and 7.0 g a.i. ha-1). The variables analyzed were the concentrations of chlorophylls a, b, carotenoids, hydrogen peroxide (H2O2), lipid peroxidation (TBARS), electrolyte leakage, and antioxidant system activity. The herbicide treatments iodosulfuron-methyl, clodinafop-propargyl, and 2,4-D decreased the concentrations of chlorophylls and carotenoids in wheat plants. The herbicides promoted oxidative stress with increased H2O2 and TBARS concentrations. Increasing the dose of iodosulfuron-methyl provided a reduction in the activity of the enzymatic antioxidant system in wheat and ryegrass. [ABSTRACT FROM AUTHOR]

The increasing contamination of soil with heavy metals poses a problem to environmental sustainability. Among these pollutants, lead is particularly concerning due to its persistence in the environment, with harmful effects on human health and ecosystems. Various strategies that combine phytoremediation techniques with soil amendments have emerged to mitigate lead contamination. In this context, biochar has gained significant attention for its potential to enhance soil quality and remediate metal-contaminated environments. This study aims to investigate the combined effect of biochar amendments on the phytoremediation of lead-contaminated shooting range soils. A series of experiments were conducted to determine the impact of the amount and distribution of biochar on lead removal from soil. Soil samples were incubated with biochar for one week, after which two types of seeds (Brassica rapa and Lolium perenne) were planted. Plant and root lengths, as well as the number of germinated seeds, were measured, and a statistical analysis was conducted to determine the influence of the amendments. After one month, the Pb concentration decreased by more than 70%. Our results demonstrate that seed germination and plant growth were significantly better in soil samples where biochar was mixed rather than applied superficially, with the optimal performance observed at a 10% wt. biochar amendment. Additionally, the combined use of biochar and phytoremediation proved highly effective in immobilizing lead and reducing its bioavailability. These findings suggest that the combination of biochar, particularly when mixed at appropriate concentrations, and Brassica rapa significantly improved lead removal efficiency. [ABSTRACT FROM AUTHOR]

Areas contaminated with cadmium require remediation because it is a highly toxic element. The aim of this study was to assess the Cd tolerance of four grass species (Poa pratensis, Lolium perenne, Festuca rubra, and Festuca pratensis) and to identify the most useful grass for the phytostabilization of areas with extremely high Cd content in the soil. Additionally, the relationship between grass tolerance to Cd and the glutathione (GSH) content in shoots was examined. Two series of pot experiments were carried out using soil artificially contaminated with Cd. Three levels of contamination were used—30, 60, and 130 mg kg−1 Cd—against a control. The plants were cut down 2 months after sowing. At the Cd1 level, L. perenne showed the highest tolerance to Cd (tolerance index TI = 86), while P. pratensis had the lowest tolerance (TI = 65). At Cd2, the TIs ranged from 52 to 59, indicating a similar tolerance of all species. Cd3 was most harmful to L. perenne (TI = 24), while P. pratensis was the most tolerant (TI = 31). Grassroots accumulated much more Cd than shoots. L. perenne showed the greatest increase in root Cd at each contamination level, followed by F. pratensis and then P. pratensis and F. rubra. It is noteworthy that the tolerance of grasses to Cd3 was related to the GSH content in shoots. P. pratensis and F. rubra increased the GSH content 4.6 and 3.6 times, respectively, while L. perenne and F. pratensis only increased it 2.3 times compared to the control plants. [ABSTRACT FROM AUTHOR]

Plant roots significantly reduce soil detachment by overland flow. However, there have been few studies on how plant growth time and hydrodynamic characteristics affect the erosion‐reducing potential of plant roots. This study cultivated ryegrass (Lolium perenne L.) and alfalfa (Medicago sativa L.) as representative of plants possessing fibrous roots and taproots, respectively, in silty soil from the Loess Plateau, China. Root‐soil composites were collected monthly from March to September 2021 and subjected to flow scouring in a hydraulic flume at a 15° slope using five different flow discharges (0.05, 0.1, 0.15, 0.2 and 0.3 L s−1). The results of the study indicated that root length density, root surface area density and root mass density exhibited a significant increase during the early growth phase, followed by a slight decrease. All parameters of fibrous roots revealed greater values than those of taproots, except for root mass density. The reduction in soil detachment under varying flow shear stresses showed a significant increase during the early phases of growth, followed by a gradual decline. Notably, fibrous roots demonstrated a greater impact on soil detachment than taproots, and this discrepancy fluctuated over time. Moreover, the contributions of fibrous and taproots to reducing soil detachment decreased from 55.81% to 39.66% and from 38.21% to 20.99% with increasing flow shear stress, respectively. It indicated that the erosion‐reducing potential of plant roots was greater when subjected to low‐flow shear stress compared to high‐flow shear stress. This study can provide a scientific basis for understanding the erosion‐reducing potential of plant roots at different growing stages and under varying hydrodynamic characteristics. [ABSTRACT FROM AUTHOR]

Abstract [Objective] The study aims to investigate the chemosensory effect of fading leaves of Ziziphus jujuba, Juglans regia, and Malus pumila in northern Shaanxi, and to provide theoretical guidance for the selection of suitable grass species under economic forests. [Methods] Outdoor potting forage Lolium perenne and Medicago sativa were set up with different concentrations of Z. jujuba, J. regia, and M . pumila withered leaf extracts (0.1, 0.05, 0.025, 0.012 5 g/mL) treatments to determine the growth and physiological indexes of the forage. [Results] (1) The dry mass of forage monocultures was significantly lower than the control in most of the three types of withered leaves treated with each concentration of leachate, and the decrease was smaller in the Z. jujuba leachate. (2) Forage malondialdehyde content was higher than the control under all three types of leachate treatments, while the increase in Z. jujuba leachate was smaller, and the changes in its chlorophyll content, ascorbic acid content and antioxidant enzyme activity differed significantly among the three types of leachates, and the variability of L. perenne was significantly greater than that of M . sativa. (3) There were significant differences in the effects of the three types of extracts on the root traits of the forages, all of which inhibited their root length growth, significantly inhibited the number of L. perenne root tips, and promoted the number of M . sativa root tips. [Conclusion] Three kinds of fruit tree leaf extract showed significant inhibition on the growth of two kinds of forage grasses, and the inhibitory effect of Z. jujuba extract was the smallest, and the growth of L. perenne was less inhibited than that of M . sativa.

Perennial ryegrass (PRG; Lolium perenne) remains the backbone of grass swards in Northern Ireland due to its improved digestibility persistence, and ease of management compared with other grass species. However, innovative breeding approaches are needed that include positive environmental outcomes, as well as improved productivity in ruminants. The objective of this study was to evaluate the feasibility of root-trait screening and selection using the in situ coring method under commercial grass breeding field conditions. 108 root cores were sampled over a 2-year period from a field trial sown in autumn 2021. Root cores were washed, scanned, and analysed using the open-access root scanning platform Rhizovision. A seasonal effect was noted whereby significant differences were detected in October for root volume, network area, and surface area, but no significant differences for any root parameter were detected in April. No association was observed between root volume, network area, or surface area at the October sampling with either dry matter (DM) yield at the 4th cut (October) or annual DM yield. These results suggest that this method may be useful for identifying improved germplasm in PRG for root characteristics; however, being comparatively labour and time intensive this method may not be practicable for large-scale breeding programmes.

Excess water is an abiotic stress in plants, but the level at which excess water becomes varies widely between plant species. We conducted a two growing season replicated excess flooding experiment that was planted with 24 accessions of perennial ryegrass which had been vegetatively propagated to ensure equal representation of genotypes within an accession, both cultivars and ecotypes, from various geographical origins. The excess water treatment applied over the winter periods was achieved with irrigation. Yields increased in the winter-flooded treatment in contrast to the non-artificial watered control treatment significantly in 2017. In 2018 the same trend could be seen, but was not significant. Differences in composition of macro- and micronutrient profiles were observed. Sulphur was the only element with highly significantly increased concentration (0.25%) in flooded samples compared to control. Phosphorus, copper, iron, manganese, and molybdenum decreased statistically significantly under flooded conditions. In conclusion, perennial ryegrass is coping extremely well with excess water supplied over the winter period and can utilise it effectively in spring.

Opportunities exist to accelerate genetic gain in forage breeding using genome-wide selection approaches. In this study, we evaluated rapid cycle recurrent genomic selection (GS) as a means of improving genetic gain for value of annual forage yield. A small population of tetraploid half-sib families was evaluated for seasonal forage yield over two years, and the maternal parent plants were genotyped and genomic prediction models developed. The GS model for value of annual forage yield had a predictive ability of 0.23. An initial round of among-family selection based on field evaluations and within-family selection using genomic estimated breeding values was performed. This was followed by two further GS cycles. New synthetics were produced after each round of selection and were established in a field trial alongside the starting population. A positive response to selection was observed in new synthetics after two successive rounds of rapid cycle recurrent genomic selection before declining in the third round. The genetic gain for the value of annual forage yield was 2.4% from C0 SYN-1 to C1 SYN-1 and 6.4% from C1 SYN-1 to C2 SYN-1. In the case of C0 to C1, genetic gain was compounded by among-family selection based on field evaluations. The implementation of rapid cycle recurrent genomic selection offers an opportunity to increase genetic gain; however, the predictive ability is likely to decay rapidly as selection candidates become more distant from the training population.

Abstract Background Perennial ryegrass (Lolium perenne) in New Zealand pastures is typically infected with the mutualist Epichloë fungal endophyte. This endophyte assists the plant in resisting biotic and abiotic stresses, but the standard strain of endophyte is toxic to livestock. Elite ryegrasses with selected endophytes have been developed to provide protective properties to the grass plant and lessen or eliminate the negative impacts on livestock. Methods Using immunology and molecular techniques, the presence of endophyte infection and endophyte strain in ryegrass tillers was determined for 24 dairy pastures sampled for up to 7 years in regions of the North and South Islands. Results In general, infection levels were high and showed small increases over time. Some pastures failed to reach 70% infection. The sown, selected endophytes were the dominant endophyte strains present and these were stable over time. Standard endophyte was the primary nonsown endophyte, and while generally low and so of little importance, it increased over time and for some pastures, this would have been detrimental to livestock. Pasture establishment technique influenced the level of contamination. Conclusions Results reinforce the importance of following best practice procedures in the seed industry and on‐farm. Researchers should monitor trials for contaminating nonsown standard endophyte.

Background: Seed retention is the basic prerequisite for seed harvest. However, only little breeding progress has been achieved for this trait in the major forage grasses. The aim of this study was to evaluate the potential of plant genetic resources of the important fodder grasses Festuca pratensis Huds. and Lolium perenne L. as source for seed retention in the breeding process. Furthermore, the morphology of the abscission zone, where shattering occurs, was studied on the cell tissue level in different developmental stages of contrasting accessions. Results: 150 and 286 accessions of Festuca pratensis and Lolium perenne were screened for seed retention, respectively. Contrasting accessions were selected to be tested in a second year. We found a great variation in seed retention in Festuca pratensis and Lolium perenne, ranging from 13 to 71% (average: 35%) and 12 to 94% (average: 49%), respectively, in the first year. Seed retention was generally lower in the second year. Cultivars were within the accessions with highest seed retention in Festuca pratensis, but had lower seed retention than ecotypes in Lolium perenne. Field-shattered seeds had a lower thousand grain weight than retained seeds. Cell layers of the abscission zone appeared already in early seed stages and were nested within each other in accessions with high seed retention, while there were two to three superimposed layers in accessions with low seed retention. Conclusions: Plant genetic resources of Lolium perenne might be a valuable source for breeding varieties with high seed retention. However, simultaneous selection for high seed weight is necessary for developing successful commercial cultivars. [ABSTRACT FROM AUTHOR]

Background: Perennial ryegrass (Lolium perenne) in New Zealand pastures is typically infected with the mutualist Epichloë fungal endophyte. This endophyte assists the plant in resisting biotic and abiotic stresses, but the standard strain of endophyte is toxic to livestock. Elite ryegrasses with selected endophytes have been developed to provide protective properties to the grass plant and lessen or eliminate the negative impacts on livestock. Methods: Using immunology and molecular techniques, the presence of endophyte infection and endophyte strain in ryegrass tillers was determined for 24 dairy pastures sampled for up to 7 years in regions of the North and South Islands. Results: In general, infection levels were high and showed small increases over time. Some pastures failed to reach 70% infection. The sown, selected endophytes were the dominant endophyte strains present and these were stable over time. Standard endophyte was the primary nonsown endophyte, and while generally low and so of little importance, it increased over time and for some pastures, this would have been detrimental to livestock. Pasture establishment technique influenced the level of contamination. Conclusions: Results reinforce the importance of following best practice procedures in the seed industry and on‐farm. Researchers should monitor trials for contaminating nonsown standard endophyte. [ABSTRACT FROM AUTHOR]

Simple Summary: This study investigates the impact of endophyte-infected ryegrass and the alkaloids (such as peramine) which it produces, on the Argentine stem weevil (Listronotus bonariensis), a pest affecting pastures crucial for extensive agriculture. Seven unnamed lines (LE161-LE167), and two Lolium perenne cultivars, Jumbo and Alto AR1, were evaluated. Leaves from LE164, LE166, and ALTO AR1 led to significant weight reduction in L. bonariensis (−13.3%, −17.1%, and −18.2%, respectively). The corresponding alkaloidal extracts from these lines, grown in greenhouse trials, exhibited an antifeedant effect in laboratory assays, resulting in reduced weevil weight (−12.5%, 8.8%, and 4.9%, respectively). When incorporated into an artificial diet, peramine induced an antifeedant effect. Liquid chromatography analysis revealed the presence of peramine in LE164, LE166, and ALTO AR1 (ranging from 46.5 to 184.2 ng g−1), while it was absent in Jumbo and other lines. These findings suggest that endophyte-induced peramine production in specific ryegrass lines negatively impacts the feeding performance of L. bonariensis, presenting a potential ecological approach for pest control in pastures crucial for extensive agriculture. One of the primary supports for extensive agriculture is pasture, which can suffer severe damage from insects including the Argentine stem weevil, Listronotus bonariensis. The main control method has been the infection of ryegrass with an endophyte fungus, forming a symbiotic association that produces alkaloids. In this study, we evaluated the impact of endophyte and peramine production on the weight of L. bonariensis across seven unnamed lines (LE161-LE167), and two Lolium perenne cultivars: Jumbo and Alto AR1. L. bonariensis adults fed on leaves from LE164, LE166, and ALTO AR1 showed weight losses of 13.3%, 17.1% and 18.2%, respectively. Similarly, the corresponding alkaloidal extract from LE164, LE166, and ALTO AR1 exhibited an antifeedant effect on L. bonariensis adults in laboratory assays, as observed through weight loss or low weight gain (−12.5%, 8.8% and 4.9%, respectively). Furthermore, one alkaloid, peramine, also elicited an antifeedant effect when incorporated into an artificial diet. Liquid chromatographic analysis of the alkaloid extract revealed that peramine was present in LE164, LE166 and ALTO AR1 in amounts ranging from 46.5–184.2 ng/g. Peramine was not detected in Jumbo and the remaining experimental lines. These data suggest that L. bonariensis were susceptible to peramine produced from endophyte infection in experimental lines LE164 and LE166, as well as ALTO AR1, affecting their feeding behavior. [ABSTRACT FROM AUTHOR]

Plants especially need to adapt to all different light environments (shade, high light, etc.) due to the essential role of light in plant life. Either shade or high-light microenvironmental conditions are common for cool-season turfgrasses, such as perennial ryegrass (Lolium perenne L.). In order to study how a plant highly conserves microRNA, miR164-affected perennial ryegrass were studied under different light intensities. OsmiR164a-overexpression (OE164), target mimicry OsmiR164a (MIM164), and CRES-T (chimeric repressor gene-silencing technology) OsNAC60 (NAC60) transgenic plants and wild-type (WT) plants were evaluated in both field (shade and full sun) and growth chamber conditions (low, medium, and high PAR at 100, 400, and 1200 µmol s−1 m−2). Morphological and physiological analysis showed miR164 could fine-tune perennial ryegrass adaptation to changing light intensity, possibly via the regulation of target genes, such as NAC60. Overall, OE164 and NAC60 plants were similar to each other and more sensitive to high light, particularly under the field condition, demonstrated by smaller size and much poorer grass quality; MIM164 performed more like WT plants than either the OE164 or NAC60 plants. This study indicates the potential of genetic manipulation of miR164 and/or its targeted genes for turfgrass adaptation to changing light environments, and future research to further investigate the molecular mechanism beneath would be warranted. [ABSTRACT FROM AUTHOR]

The 18O enrichment (Δ18O) of cellulose (Δ18OCel) is recognized as a unique archive of past climate and plant function. However, there is still uncertainty regarding the proportion of oxygen in cellulose (pex) that exchanges post‐photosynthetically with medium water of cellulose synthesis. Particularly, recent research with C3 grasses demonstrated that the Δ18O of leaf sucrose (Δ18OSuc, the parent substrate for cellulose synthesis) can be much higher than predicted from daytime Δ18O of leaf water (Δ18OLW), which could alter conclusions on photosynthetic versus post‐photosynthetic effects on Δ18OCel via pex. Here, we assessed pex in leaves of perennial ryegrass (Lolium perenne) grown at different atmospheric relative humidity (RH) and CO2 levels, by determinations of Δ18OCel in leaves, Δ18OLGDZW (the Δ18O of water in the leaf growth‐and‐differentiation zone) and both Δ18OSuc and Δ18OLW (adjusted for εbio, the biosynthetic fractionation between water and carbohydrates) as alternative proxies for the substrate for cellulose synthesis. Δ18OLGDZW was always close to irrigation water, and pex was similar (0.53 ± 0.02 SE) across environments when determinations were based on Δ18OSuc. Conversely, pex was erroneously and variably underestimated (range 0.02–0.44) when based on Δ18OLW. The photosynthetic signal fraction in Δ18OCel is much more constant than hitherto assumed, encouraging leaf physiological reconstructions. Summary statement: The proportion of oxygen in leaf cellulose which is derived from leaf sucrose in Lolium perenne is much more constant and predictable than was hitherto assumed, encouraging reconstructions of photosynthetic information [ABSTRACT FROM AUTHOR]

Aims: To develop a methodology to study uptake and redistribution by plants of NH4+ from deep soil, applying it to investigate deep root N uptake by cultivated grassland species. Methods: A slow-release 15NH4+ label adsorbed to clinoptilolite was placed into soil (depth 42 cm) well below the densest root zone in well-established monospecific stands of five grass and two clover species. Species showing a variety of deep rooting patterns, N acquisition strategy, forage qualities, and persistence in hemiboreal conditions were chosen. The label was placed in early spring and tracked throughout one or two growing seasons in two repeated experiments. Results: After two growing seasons ~ 90% of the label was tracked in the soil and harvested herbage of grasses, less in clovers. Deep N uptake was limited in spring, increased during mid-season, and was strongest in autumn in all species, despite lower herbage yield in autumn. Species differed in ability to recover and maintain 15N in the soil–plant system. In one growing season, Lolium perenne L., Phleum pratense L., Schedonorus pratensis (Huds.) P.Beauv. and Schedonorus arundinaceus (Schreb.) Dumort herbage recovered ~ 65% of the label, Poa pratensis L. 54%, and Trifolium pratense L. and Trifolium repens L. 36–48%. Label transport to topsoil was observed, mainly attributable to plant nutrient redistribution rather than physical diffusion. Conclusions: The innovative slow-release 15N label enabled tracing species differences and seasonal changes in uptake of NH4+ from deep soil. Among the tall-growing grasses, growth vigor appeared as important for deep N uptake as expected root depth. [ABSTRACT FROM AUTHOR]

Perennial ryegrass (Lolium perenne L.) has potential in the phytoremediation of cadmium (Cd)-contaminated soil due to its strong Cd accumulation capacity and high biomass. In this study, we investigated the growth physiology, Cd accumulation, and metabolites of L. perenne roots under different soil acid stress levels (pH 4.0, 4.5, 5.0 and 6.0) and Cd concentrations (100 and 0 mg/kg) after 90 days of growth. The results showed that soil acid stress significantly impacts the remediation capability and physiological metabolic properties of L. perenne. Based on root Cd content and enrichment coefficient, soil pH between 4.5 and 5.0 was more conducive to Cd accumulation. The growth physiology and Cd accumulation of L. perenne were inhibited under high soil acid stress (pH 4.0). High soil acid stress caused a decrease in root length, root volume, and root biomass of L. perenne. Root malondialdehyde (MDA) content and the activity of antioxidant enzymes (catalase (CAT) and peroxidase (POD)) increased significantly in response to high soil acid stress to enhance tolerance. Metabolomics analysis revealed that acid stress resulted in significant changes in certain metabolites. Tartaric acid, fructose and amino acids (glutamate and lysine) in the roots of L. perenne were compatible solutes under acid stress. This study indicated that L. perenne has strong physiological and metabolic tolerance, as well as Cd accumulation ability, in response to soil acid stress. [ABSTRACT FROM AUTHOR]

The study investigated how the concentration and composition of purified tannin extracts, at various inclusion rates, affect the ruminal in vitro fermentation parameters. Tannin extracts were isolated from four different forage species: birdsfoot trefoil (Lotus corniculatus), sulla (Hedysarum coronarium), big trefoil (Lotus pedunculatus), and salad burnet (Sanguisorba minor). Plants extracts were purified by Sephadex LH-20 gel chromatography and analyzed by UPLC–ESI–MS/MS. The results showed a large variation among the extracts from different species in terms of tannin composition and structural features. The extracts from salad burnet were dominated by hydrolysable tannins, comprising mainly ellagitannins. The extracts derived from sulla and big trefoil contained predominantly proanthocyanidins (PA), primarily composed of prodelphinidins with high mean degree of polymerisation (mDP). Birdsfoot trefoil extracts comprised procyanidin-rich PAs with low mDP. To determine whether the combined presence of tannins and flavonoid together lead to synergistic or antagonistic effects, the tannin extracts were incubated both with or without rutin at concentrations of 10, 20, and 30 g/kg DM, using a base substrate of perennial ryegrass (Lolium perenne, control). In general, all the tannin extracts decreased methane (CH4) production compared to the control, while no significant effect of rutin was observed on both gas (GP) and CH4 production, neither pure, nor in the simultaneous presence of tannins. The highest CH4 reduction (15%, at 30 g/kg DM) was observed from sulla and big trefoil extracts compared to control, but this was also supplemented with a concomitant reduction in GP (11%) indicating a reduction in feed digestibility. The extracts from birdsfoot trefoil and salad burnet reduced CH4 by up to 12% without significantly reducing GP, indicating the importance of tannin composition on ruminal fermentation. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effects of organic amendments on saline-alkali soil improvement were compared. • The optimal blending ratio of organic amendments was 20%. • High-temperature pretreatment compost favored soil improvement and plant growth. • High-temperature pretreatment composting improved plant antioxidant capacity. • Plant growth was improved by altering soil-dominant microflora and composition. Short-term high-temperature pretreatment can effectively shorten the maturity period of organic waste composting and improve the fertilizer efficiency and humification degree of products. To investigate the effect and mechanism of the end products on the saline–alkali soil improvement and plant growth, the short-term high-temperature pretreatment composting (SHC) and traditional composting (STC) were separately blended with saline–alkali soil in a ratio of 0–40 % to establish a soil–fertilizer blended matrix for cultivating Lolium perenne L. The pot experiments combined with principal component analysis showed Lolium perenne L. planted in 20 % SHC-blended saline–alkali soil had the best growth effect, and its biomass, chlorophyll content, and plant height were 109–113 % higher than STC. The soil physicochemical property analysis showed that SHC and STC increased the soil nutrient content, humification degree, and enzyme activity at any blending ratio. The microbial analysis showed that 20 % SHC in the saline–alkali soil stimulated the growth of functional microorganisms and the addition of SHC promoted the sulfur cycle, nitrogen fixation, and carbon metabolism in the soil–plant system. The correlation analysis showed that pH; nutrient contents; and urease, catalase, sucrase, and phosphatase activities in the saline–alkali soil were significantly correlated with plant growth indexes (p < 0.05). Georgenia and norank_f__Fodinicurvataceae had a stronger correlation with four types of enzyme activities (p < 0.01). SHC improved the saline–alkali soil and promoted plant growth by adjusting soil pH, increasing soil nutrients, and influencing soil enzyme activity and dominant flora. This study provides a theoretical basis for applying SHC products in soil improvement. [ABSTRACT FROM AUTHOR]

Perennial ryegrass is the most widely grown temperate grass species globally as a source of forage (grazing, hay, silage) or for amenity use. It is a part of landscape, protects soil from water and wind erosion, enriches it with organic substances and improves its fertility. During the period 2015-2020 in the Institute of Forage crops (IFC) - Pleven a collection nursery was studied in field non-irrigated conditions on leached black soil, in block duplicate method, in 2 replications with a total of 19 accessions of perennial ryegrass, with 50 individual plants each (25 plants for forage and 25 plants - for seeds), including 14 varieties and 5 ecotypes, 10 tetraploid and 9 diploid, from Bulgaria (BG), Belgium (BE), and Romania (RO). The aim is to determine the vitality per year and longevity (after many years, more than 3-4) of perennial ryegrass collection accessions and to make a selection of the most vital and long - lasting genotypes. Scale of survival according to the International Classifier for the family Poaceae (Bukhteeva et al., 1985) was used - limiting factors of the environment are cold - winter, drought and high temperatures - summer. An autumn inventory of the individual plants no./% was carried out annually, as 25 plants per sample = 100%., and vitality classification as follows: Very Low - less than 1 to 20% of plants are left alive; Low - more than 21 to 50%; Medium - more than 51% to 70%; High - more than 71 to 90%; Very High - more than 90% of the plants are still alive. Computer statistical processing of the data (via Excel, at P = 0.05) included variance analyses. Data on vitality and longevity are characterized by: marginal values (min and max), arithmetic mean (x), standard deviation (SD) and coefficient of variation (CV,%). Variation was considered weak, moderate, or strong at CV values, respectively: up to 10%; > 10-20%, and > 20% (Dimova and Marinkov, 1999). When grown for fodder, the local ecotypes Sokolare, Topolovgrad and Bekovi skali are the most viable by years and the longest surviving up to 5 years, with the percentage of plants alive in the fifth year being the highest for the Sokolare ecotype. Ecotype Sokolare is strongly influenced by the method of use, which is the longest-lasting and most viable when grown for fodder - 5 years and the shortest - when grown for seeds - 3 years. All diploid varieties live up to 4 years, and only the Harmoniya variety up to 5 years, with the Bulgarian varieties Harmoniya and Strandzha being the most viable and long-lasting when grown for fodder. Harvesting once a year for seeds extends the life cycle of diploid varieties up to 5 years and for the Harmoniya variety - up to 6. The Bulgarian tetraploid varieties Tetrany, Tetramis and the Belgian varieties Floris, Melpetra and Melverde are the most durable and long-lasting. One-time harvesting per year for seeds extends the life cycle of the tetraploid varieties up to 5 years, and for the Bulgarian varieties Tetrany, Tetramis and the Belgian varieties Floris, Melpetra and Melverde - up to 6. [ABSTRACT FROM AUTHOR]

Biofertilizers with phosphate-solubilizing microorganism (PSM) inoculations have been suggested to diminish the limitation of phosphorus (P) deficiency in plants. However, their applications in agriculture are restricted due to the inconstant effects of various PSMs. Proper carriers for the inoculations may overcome this shortcoming and improve PSMs' effectiveness. The objective of this study was to investigate whether straw compost, a type of organic material, can act as a carrier for improving the efficiencies of phosphate-solubilizing bacteria and fungi named Acinetobacter sp. and Aspergillus niger, respectively, in soils. We monitored the growth and cellular physiological responses of one type of model plants, named perennial ryegrass (Lolium perenne L.), under four soil treatments, including non-fertilization, PSM inoculation alone, straw compost addition alone, and the combined applications of both PSMs and straw compost. We found the combined treatments significantly improved the growth by 14.7% for shoot height and 79.7% for shoot weight, respectively, on average. P and potassium (K) uptakes of ryegrass were also increased by 102.5% and 65.3%, respectively, after the application of both PSMs and straw compost. Furthermore, physiological properties, such as photosynthetic efficiency and P-transportation capacity, of ryegrass were also significantly improved under combined treatments when compared to other treatments, regardless of the types of PSM included. The piecewise structural equation model further indicated that PSM inoculation and straw compost input are synergistically contributing to the nutrient uptake of ryegrass through many direct and indirect ways. We propose that straw compost is a good carrier material for PSMs' survival and would improve their plant growth promotion ability in soil. Our results provide valuable insights into the exploitation and utilization of P-biofertilizers in agriculture. [ABSTRACT FROM AUTHOR]

Increasing the ultraviolet radiation (UV) level, particularly UV-B due to damage to the stratospheric ozone layer by human activities, has huge negative effects on plant and animal metabolism. As a widely grown cool-season forage grass and turfgrass in the world, perennial ryegrass (Lolium perenne) is UV-B-sensitive. To study the effects of miR164, a highly conserved microRNA in plants, on perennial ryegrass under UV stress, both OsmiR164a overexpression (OE164) and target mimicry (MIM164) transgenic perennial ryegrass plants were generated using agrobacterium-mediated transformation, and UV-B treatment (~600 μw cm−2) of 7 days was imposed. Morphological and physiological analysis showed that the miR164 gene affected perennial ryegrass UV tolerance negatively, demonstrated by the more scorching leaves, higher leaf electrolyte leakage, and lower relative water content in OE164 than the WT and MIM164 plants after UV stress. The increased UV sensitivity could be partially due to the reduction in antioxidative capacity and the accumulation of anthocyanins. This study indicated the potential of targeting miR164 and/or its targeted genes for the genetic manipulation of UV responses in forage grasses/turfgrasses; further research to reveal the molecular mechanism underlying how miR164 affects plant UV responses is needed. [ABSTRACT FROM AUTHOR]

Background: Struvite, biochar and ash products (collectively known as STRUBIAS) derived from different waste streams are used as fertilisers in agriculture. Raw dairy processing sludge (DPS) shows promise as bio‐based fertilisers, but secondary STRUBIAS‐derived products need further testing as fertilisers. Aims: The objective of this study was to calculate the phosphorus mineral fertiliser equivalency (P‐MFE) for some STRUBIAS products derived from DPS. Methods: Ryegrass (Lolium perenne L.) and wheat (Triticum aestivum) pot trials were used to determine the P‐MFE using the apparent P recovery (APR) method for Fe‐DPS and DPS‐derived struvites (Struvite 1–4), hydrochars (HC1–3) and ash. Results: The tested STRUBIAS products can be divided into two groups: (1) a range of products that can (i.e. Struvite 1–3) and (2) cannot (i.e., Struvite 4, HC1–3, ash and Fe‐DPS) be considered fertilisers. In the first group, the P‐MFE ranged from 66.8% to 76.7% for ryegrass and from 77.9% to 93.5% for spring wheat grain. In the second group, the P‐MFE ranged from 7.8% to 58.3% for ryegrass and from −34.5% to −151.3% for spring wheat grain. The negative agronomic effects of some products for wheat grain (struvite and HC) in this study were mainly caused by high Fe content, which could be overcome by improved treatment processes. Conclusions: Future policy and research must be aware that not all the DPS‐derived STRUBIAS products are suitable as fertilisers and therefore need to be tested individually. [ABSTRACT FROM AUTHOR]

The objective of this study was to quantify the farm gate nitrogen (N) offset potential of perennial ryegrass (Lolium perenne L.; PRG) white clover (Trifolium repens L.; WC) swards by comparing the herbage and milk production from dairy farmlets that were simulations of full farming systems. A study was established where 120 cows were randomly assigned to 4 farmlets of 10.9 ha (stocking rate: 2.75 cow/ha), composed of 20 paddocks each. Cows were fed 526 kg of DM of concentrate on average each year. The 4 grazing treatments were PRG-only at 150 or 250 kg of N/ha and PRG-WC at 150 or 250 kg of N/ha. Cows remained in their treatment group for an entire grazing season and were re-randomized as they calved across treatments each year. As cows calved in the spring as standard practice in Ireland, they were rotationally grazed from early February both day and night (weather permitting) to mid-November, to a target postgrazing sward height of 4.0 cm. Mean sward WC content was 18.1% and 15.4% for the 150 and 250 kg of N/ha PRG-WC treatments, respectively over the 3-yr period. When WC was included, lowering the N rate did not reduce pregrazing yield, pregrazing height, or herbage removed, but those factors decreased significantly when WC was absent. Total annual herbage DM production was 13,771, 15,242, 14,721, and 15,667 kg of DM/ha for PRG-only swards receiving 150 or 250 kg of N/ha and PRG-WC swards receiving 150 or 250 kg of N/ha, respectively. In addition, when WC was present, compressed postgrazing sward heights were lower (4.10 vs. 4.21 cm) and herbage allowance (approximately 17 kg/cow feed allocation per cow per day) higher than the high-N control (+ 0.7 kg of DM/cow per day). There was a significant increase in milk production, both per cow and per hectare, when WC was included in PRG swards. Over the 3-yr study, cows grazing PRG-WC had greater milk (+304 kg) and milk solids (+31 kg of fat + protein) yields than cows grazing PRG-only swards. This significant increase in milk production suggests that the inclusion of WC in grazing systems can be effectively used to increase milk production per cow and per hectare and help offset nitrogen use. This result shows the potential to increase farm gate N use efficiency and reduce the N surplus compared with PRG-dominant sward grazing systems receiving 250 kg of N/ha, without negatively affecting milk solids yield or herbage production, thus increasing farm profit by €478/ha. [ABSTRACT FROM AUTHOR]

Diversification of agricultural practices, including changes in crop rotation, intercropping or cover cropping, influence the soil microbiome. Here the impact of tillage and crop diversification on the soil microbiome is reported, being one of the few boreal studies. The field experiment consisted of four treatments with four replications all having a short cereal rotation practice namely an oat (Avena sativa) – spring barley (Hordeum vulgare) – wheat (Triticum aestivum) rotation for the past 10 years until spring 2018. During that period two of the treatments were conventionally tilled with moldboard ploughing whereas the other two were no-tillage treatments. From the growing season 2018 until fall 2020 the main crop in all treatments was spring barley. The first conventional tillage treatment was diversified with English ryegrass (Lolium perenne) as an undersown cover crop for the next three growing seasons. The first no-tillage treatment continued with spring barley only. The second conventional tillage and no-tillage treatment had winter rapeseed in rotation in 2019. Bulk soils were sampled in May 2018 before diversification and then in October 2018, 2019, and 2020. The results showed a clear effect of tillage on the beta-diversity of the soil microbiome and an increase in fungal richness. Barley monoculture interrupted with winter rapeseed resulted in a minor change of the fungal and bacterial community composition. Other fungal and bacterial alpha diversity measures did not react to tillage or diversification nor did the gene copy abundances involved in the N cycle. In conclusion tillage had a profound effect on the soil microbiome hindering impact of the diversification. [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]

Aluminum (Al) toxicity and phosphorus (P) deficiency are widely recognized as major constraints to agricultural productivity in acidic soils. Under this scenario, the development of ryegrass plants with enhanced P use efficiency and Al resistance is a promising approach by which to maintain pasture production. In this study, we assessed the contribution of growth traits, P efficiency, organic acid anion (OA) exudation, and the expression of Al-responsive genes in improving tolerance to concurrent low-P and Al stress in ryegrass (Lolium perenne L.). Ryegrass plants were hydroponically grown under optimal (0.1 mM) or low-P (0.01 mM) conditions for 21 days, and further supplied with Al (0 and 0.2 mM) for 3 h, 24 h and 7 days. Accordingly, higher Al accumulation in the roots and lower Al translocation to the shoots were found in ryegrass exposed to both stresses. Aluminum toxicity and P limitation did not change the OA exudation pattern exhibited by roots. However, an improvement in the root growth traits and P accumulation was found, suggesting an enhancement in Al tolerance and P efficiency under combined Al and low-P stress. Al-responsive genes were highly upregulated by Al stress and P limitation, and also closely related to P utilization efficiency. Overall, our results provide evidence of the specific strategies used by ryegrass to co-adapt to multiple stresses in acid soils. [ABSTRACT FROM AUTHOR]

Purpose: The study examines the efficacy of using recycled abattoir waste fertilizer as a sustainable nutrient input for crop Production. Method: Two pot experiments were set up in a controlled environment room to examine biomass yields of ryegrass (Lolium perenne AberMagic), grain yields of spring wheat (Triticum aestivum KWS Cochise), and their micro and macronutrient uptakes, respectively, in an abattoir waste organomineral fertilizer amended soil compared to those treated with inorganic NPK fertilizer. Phosphorus was added at rates of 0, 25, 50, 100, 200, 300, 400, 500, 600, 800, 1000, and 1200 mg P kg-1 in a low P south-west England soil. Results: Total biomass yields of ryegrass in the NPK treatments were higher at application rates greater than 800 mg P kg-1 soil compared with their corresponding abattoir waste organomineral fertilizer (Thallo™) treatments. Total wheat dry grain weights increased with P addition rates in both the Thallo™ and NPK amended soils until the application rates exceeded 800 mg P kg-1 when the dry grain weights started to decline. Micronutrient concentrations in grass produced from Thallo™ fertilizer-amended soils were similar to those from their corresponding NPK fertilizer treatments. Conclusion: This study demonstrated that if the Thallo™ is added at rates not exceeding 200 mg P kg-1 soil to 300 mg P kg-1 soil, it can serve as a sustainable and cost-effective alternative P source for ryegrass and wheat grain production. However, its application did not increase the micronutrient density of ryegrass or wheat grain any more than inorganic NPK additions. [ABSTRACT FROM AUTHOR]

Negative plant–soil feedback (PSF) arises when localized accumulations of pathogens reduce the growth of conspecifics, whereas positive PSF can occur due to the emergence of mutualists. Biochar, a carbon-rich material produced by the pyrolysis of organic matter, has been shown to modulate soil microbial communities by altering their abundance, diversity, and activity. For this reason, to assess the long-term impact of biochar on soil microbiome dynamics and subsequent plant performance, we conducted a PSF greenhouse experiment using field soil conditioned over 10 years with Vitis vinifera (L.), without (e.g., C) or with biochar at two rates (e.g., B and BB). Subsequently, the conditioned soil was employed in a response phase involving either the same plant species or different species, i.e., Medicago sativa (L.), Lolium perenne (L.), and Solanum lycopersicum (L.). We utilized next-generation sequencing to assess the abundance and diversity of fungal pathogens and arbuscular mycorrhizal fungi (AMF) within each conditioned soil. Our findings demonstrate that biochar application exerted a stimulatory effect on the growth of both conspecifics and heterospecifics. In addition, our results show that untreated soils had a higher abundance of grape-specialized fungal pathogens, mainly Ilyonectria liriodendra, with a relative abundance of 20.6% compared to 2.1% and 5.1% in B and BB, respectively. Cryptovalsa ampelina also demonstrated higher prevalence in untreated soils, accounting for 4.3% compared to 0.4% in B and 0.1% in BB. Additionally, Phaeoacremonium iranianum was exclusively present in untreated soils, comprising 12.2% of the pathogens' population. Conversely, the application of biochar reduced generalist fungal pathogens. For instance, Plenodomus biglobosus decreased from 10.5% in C to 7.1% in B and 2.3% in BB, while Ilyonectria mors-panacis declined from 5.8% in C to 0.5% in B and 0.2% in BB. Furthermore, biochar application was found to enrich the AMF community. Notably, certain species like Funneliformis geosporum exhibited increased relative abundance in biochar-treated soils, reaching 46.8% in B and 70.3% in BB, compared to 40.5% in untreated soils. Concurrently, other AMF species, namely Rhizophagus irregularis, Rhizophagus diaphanus, and Claroideoglomus drummondii, were exclusively observed in soils where biochar was applied. We propose that the alleviation of negative PSF can be attributed to the positive influence of AMF in the absence of strong inhibition by pathogens. In conclusion, our study underscores the potential of biochar application as a strategic agricultural practice for promoting sustainable soil management over the long term. [ABSTRACT FROM AUTHOR]

Due to the lack of conclusive articles on the effect of guano, which is classified as a natural fertiliser, an experiment was conducted to evaluate its effect on the yield and quality of perennial ryegrass of the Rela variety. The guano used in the experiment contained significant concentrations in g·kg-1 DM of nitrogen (23.1), phosphorus (9.52) and magnesium (2.90). The concentration of heavy metals did not exceed the applicable standards in organic fertilisers. The total content of N and P in guano was higher relative to K, and Mg and Ca were similar. The concentration of N and Mg in guano is comparable to the content of these elements in poultry manure. The guano reaction was slightly acidic (5.86). The fertiliser value of guano was assessed in a vegetation-weed two-factor experiment. The test scheme included control, guano and guano with ammonium nitrate applied at three doses. The dry biomass yield of perennial ryegrass from individual cuts varied considerably. The objects with applied guano and guano with ammonium nitrate increased the average yield of perennial ryegrass from cut 1 by 102.9% compared to the control object. Applied guano fertilisation significantly increased the sum of perennial ryegrass yield from three cuts. As a result of the applied fertilisation, there was an increase in N, P and Ca content in perennial ryegrass, while K and Mg content increased to a negligible extent and thus contributed to optimal ionic ratios of Ca:P and K:(Ca+Mg). In contrast, the ionic ratio K:Mg deviated significantly from the optimal values for plants. The application of guano and guano with ammonium nitrate influenced the positive correlation between N and Ca content and the obtained yield of perennial ryegrass.

The significance of green roofs in stormwater management cannot be overlooked, as they have become an integral component in the creation of sustainable cities. This study not only examined the purifying effects of substrates, but also explored the interplay between substrate and vegetation through a combination planting approach, resulting in an innovative roof greening and planting method that incorporates both substrate and vegetation. In the experiment, 16 planting combinations of green roofs were created by cross-planting four proportioned substrates and four proportioned turfgrass. Subsequently, the outflow water quality indexes including ammonium nitrogen (NH4+-N), suspended solids (SS), chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) were analyzed individually. The study findings indicate significant variations in the rainwater quality improvement capacity among the 16 green roof planting combinations, with both exhibiting effective purification of NH4+-N and SS. However, all 16 planting combinations were identified as sources of pollution for TP, TN and COD in rainwater. Among the four proportioned substrates, the combination of planting and B substrate (field soil: turfy soil: vermiculite: perlite: zeolite = 5:2:1:1:1) exhibits a superior purification effect with minimal variance. Therefore, it is recommended to promote and apply B substrate in large-scale green roofs. The A2 combination (field soil: turfy soil: perlite: vermiculite = 5:3:1:1 and Poa pratensis: Agrostis matsumurae: Lolium perenne = 5:4:1) e xhibited the highest effluent water quality among the 16 combinations tested, while other planting combinations utilizing substrate A did not perform as well. In summary, green roofs have the potential to purify rainwater but also pose a certain risk of pollution. [ABSTRACT FROM AUTHOR]

Kentucky bluegrass (Poa pratensis L.; drought resistant) and perennial ryegrass (Lolium perenne L.; drought sensitive) are economically important grass species contrasting in drought stress resistance. This study determined the optimal chlorophyll fluorescence parameters to indicate drought incidence and whether the parameters differentiate intra‐ and interspecies variations in drought stress. For each species, nine cultivars were exposed to well‐watered or drought (water withheld) conditions in growth chambers containing high‐throughput photosynthetic imagers to track real‐time responses of maximum quantum efficiency of photosystem II (Fv/Fm), quantum yield of photosystem II (ΦII), non‐photochemical quenching (NPQ), energy‐dependent quenching (qE), and photoinhibition‐associated quenching (qI). Soil moisture content and relative water content of leaf tissues were evaluated. Due to drought, Fv/Fm and ΦII decreased for cultivars of both species but earlier for perennial ryegrass compared to Kentucky bluegrass. The NPQ, qI, and qE values exhibited more dynamic and earlier changes due to drought compared to Fv/Fm and ΦII and allowed for early, mid, and late drought responses to be illustrated. Drought induced an increase in NPQ, qI, and qE values, which corresponded to activation of photoprotection mechanisms, and was exhibited earlier for perennial ryegrass compared to Kentucky bluegrass. As the drought treatment progressed, a decrease or stabilization of low values of NPQ, qI, and qE was observed, and the lowest values were associated with the most drought‐sensitive cultivars. These results indicate important stress tolerance protection mechanisms for grass species and will broadly impact basic and applied grass research as a nondestructive phenotyping tool. Core Ideas: Kentucky bluegrass and perennial ryegrass contrast in drought resistance.Chlorophyll fluorescence parameters during drought responses reveal novel insight into resistance mechanisms.Plant non‐photochemical protection strategies were activated by drought stress in both grass species.Measurements of non‐photochemical quenching parameters indicated drought responses earlier than quantum efficiency.Non‐photochemical parameters are good, early indicators of drought stress incidence in grass species. [ABSTRACT FROM AUTHOR]

Cytochrome P450s (CYPs) play crucial roles in regulating plant growth, development, and stress tolerance. In this study, a perennial ryegrass (Lolium perenne) CYP gene, LpCYP72A15, was identified as a candidate gene regulating plant osmotic stress tolerance based on a cDNA library screening in the background of yeast ∆hog1 mutant. LpCYP72A15 is localized in the plastids, and its expression was regulated by osmotic stress and ABA treatment. Overexpressing LpCYP72A15 significantly enhanced plant drought tolerance in both Arabidopsis and perennial ryegrass. Under drought stress, the transgenic ryegrass showed significant lower reactive oxygen species (ROS) levels, higher ROS‐scavenging enzymatic activities, and higher soluble sugar contents than the wildtype plants. Transient over‐expressing the gene also enhanced survival rates of ryegrass mesophyll protoplasts under H2O2‐induced oxidative or mannitol‐enforced osmotic stresses. Taken together, LpCYP72A15 confers oxidative‐ and osmotic‐stress tolerances that positively regulates plant drought tolerance in perennial ryegrass. [ABSTRACT FROM AUTHOR]

Rosavin is the characteristic component of Rhodiola rosea L., an important medicinal plant used widely in the world that has been reported to possess multiple biological activities. However, the endangered status of wild Rhodiola has limited the supply of rosavin. In this work, we successfully engineered an Escherichia coli strain to efficiently produce rosavin as an alternative production method. Firstly, cinnamate: CoA ligase from Hypericum calycinum , cinnamoyl-CoA reductase from Lolium perenne , and uridine diphosphate (UDP)-glycosyltransferase (UGT) from Bacillus subtilis (Bs-YjiC) were selected to improve the titer of rosin in E. coli. Subsequently, four UGTs from the UGT91R subfamily were identified to catalyze the formation of rosavin from rosin, with SlUGT91R1 from Solanum lycopersicum showing the highest activity level. Secondly, production of rosavin was achieved for the first time in E. coli by incorporating the SlUGT91R1 and UDP-arabinose pathway, including UDP-glucose dehydrogenase, UDP-xylose synthase, and UDP-xylose 4-epimerase, into the rosin-producing stain, and the titer reached 430.5 ± 91.4 mg/L. Thirdly, a two-step pathway derived from L -arabinose, composed of L -arabinokinase and UDP-sugar pyrophosphorylase, was developed in E. coli to further optimize the supply of the precursor UDP-arabinose. Furthermore, 1203.7 ± 32.1 mg/L of rosavin was produced from D -glucose and L -arabinose using shake-flask fermentation. Finally, the production of rosavin reached 7539.1 ± 228.7 mg/L by fed-batch fermentation in a 5-L bioreactor. Thus, the microbe-based production of rosavin shows great potential for commercialization. This work provides an effective strategy for the biosynthesis of other valuable natural products with arabinose-containing units from D -glucose and L -arabinose. • Four GGTs from UGT91R subfamily were identified to synthesize rosavin. • De novo biosynthesis of rosavin was achieved in E. coli for the first time. • UDP-arabinose salvage pathway boosted rosavin production by utilizing L-arabinose. • Fed-batch fermentation enabled production of ∼7.5 g/L rosavin from D-glucose and L-arabinose. [ABSTRACT FROM AUTHOR]

Although crop conversion from annual to perennial crops has been considered as one path towards climate-smart and resource-efficient agriculture, the effects of this conversion on soil multifunctionality and biomass yields remain unclear. The objective of the study is to enhance soil multifunctionality while exerting a marginal influence on farmer income. Here, we investigated the effects of annual winter wheat (Triticum aestivum L.) and two perennial crops (a grass (Lolium perenne L.), a legume (Medicago sativa L.), and their mixture) on soil multifunctionality and biomass yield on the Yellow River floodplain. Soil multifunctionality was assessed by the capacity of water regulation and the multifunctionality of carbon (C), nitrogen (N), and phosphorus (P) cycles. C cycle multifunctionality index is the average of β-xylosidase, β-cellobiosidase, and β-1, 4-glucosidase. N cycle multifunctionality index is the average of L-leucine aminopeptidase and β-1, 4-N-acetyl-glucosaminidase, and acid phosphatase represented (and dominated) P cycle functions. The results showed that perennial crops enhanced soil multifunctionality by 207% for L. perenne, 311% for M. sativa, and 438% for L. perenne + M. sativa, compared with annual winter wheat (T. aestivum). The effect of perennial crops on soil multifunctionality increased with infiltration rate, dissolved organic C, microbial biomass C, and extracellular enzymatic activities for both C and N acquisition. However, we observed that perennial crops had a lower biomass yield than annual crop. Therefore, the transition of agricultural landscapes to perennials needs to take into account the balance between environmental protection and food security, as well as environmental heterogeneity, to promote sustainable agricultural development. [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]

Due to the lack of conclusive articles on the effect of guano, which is classified as a natural fertiliser, an experiment was conducted to evaluate its effect on the yield and quality of perennial ryegrass of the Rela variety. The guano used in the experiment contained significant concentrations in g·kg-1 DM of nitrogen (23.1), phosphorus (9.52) and magnesium (2.90). The concentration of heavy metals did not exceed the applicable standards in organic fertilisers. The total content of N and P in guano was higher relative to K, and Mg and Ca were similar. The concentration of N and Mg in guano is comparable to the content of these elements in poultry manure. The guano reaction was slightly acidic (5.86). The fertiliser value of guano was assessed in a vegetation-weed two-factor experiment. The test scheme included control, guano and guano with ammonium nitrate applied at three doses. The dry biomass yield of perennial ryegrass from individual cuts varied considerably. The objects with applied guano and guano with ammonium nitrate increased the average yield of perennial ryegrass from cut 1 by 102.9% compared to the control object. Applied guano fertilisation significantly increased the sum of perennial ryegrass yield from three cuts. As a result of the applied fertilisation, there was an increase in N, P and Ca content in perennial ryegrass, while K and Mg content increased to a negligible extent and thus contributed to optimal ionic ratios of Ca:P and K:(Ca+Mg). In contrast, the ionic ratio K:Mg deviated significantly from the optimal values for plants. The application of guano and guano with ammonium nitrate influenced the positive correlation between N and Ca content and the obtained yield of perennial ryegrass. [ABSTRACT FROM AUTHOR]

Circular economy recycling-derived fertilizers (RDF) have the potential to replace linear economy fertilizers such as unsustainable superphosphates. Here, effects of ash RDF treatments in Irish grassland cultivation were investigated in a simulated second growing season. Soil fertilized in a preceding pot trial with superphosphate (SP), poultry-litter ash (PLA) and sewage-sludge ash (SSA) at P concentration of 60 kg P ha−1 and a P-free control (SP0) was reused in a microcosm trial. Lolium perenne was cultivated for 54 days in six replicates with a full complement of micro- and macro-nutrients other than P. PLA treatments provided higher dry weight shoot yields than SP0, while SSA and SP overlapped with SP0 and PLA. Most probable number (MPN) analysis showed that phosphonate- and phytate-utilizing bacterial abundance was significantly increased in PLA. Alkaline (phoD) phosphomonoesterase gene fragments were significantly more abundant (qPCR) in the ashes than the superphosphate or P-free control. Bacterial communities were significantly affected by the P application. Similarly, a significant separation of treatments was confirmed in a canonical correspondence analysis of the phoD-harboring community. The genera Streptomyces and Xanthomonas were significantly higher in abundance in the ash RDFs. These results demonstrated the potential benefits of ash RDF treatments as an alternative P source. [ABSTRACT FROM AUTHOR]

Rapid identification of herbicide-resistant weeds plays a crucial role in their management. Glyphosate resistance in Lolium perenne is a growing issue in New Zealand and can be conferred by a single nucleotide polymorphism (SNP) causing amino acid substitutions at codon 106 in the 5-enolpyruvoylshikimate-3-phosphate synthase (EPSPS) gene. High-throughput molecular (HTM) methodologies that can detect such SNPs include high-resolution melting and real-time quantitative PCR probe assays. Here, we compare the effectiveness of both assays with a more labour-intense derived cleaved amplified polymorphic sequence (dCAPS) test for detecting SNPs at codon 106. The results showed that both HTM assays detected mutations at this codon, and their results were consistent with those of the dCAPS. Unlike dCAPS, however, the HTM assays over-estimated homozygosity for the glyphosate resistance allele. Nevertheless, cost-effective high-throughput detection of resistance is more important than the zygosity status when initiating an on-farm management response. In summary, both HTM assays successfully identified glyphosate resistance alleles at codon 106 in the EPSPS gene. Given that both assays are more cost-effective and can screen a larger number of samples in a timely manner compared to the dCAPS method, they can be used as quick tests for detecting glyphosate resistance in L. perenne. [ABSTRACT FROM AUTHOR]

Resistance to iodosulfuron, a herbicide targeting acetolactate synthase (ALS), was identified and characterised in a population of Lolium perenne L. from Canterbury, New Zealand. The resistant population was 264 times more resistant to iodosulfuron than a susceptible population, based on a ratio of the rate corresponding to a 50% reduction in resistant and susceptible plant survival (R/S LD50). The resistant population was also 14-times more resistant to nicosulfuron, another ALS-inhibitor of the same class. However, no resistance to imazapyr, an ALS-inhibitor from a different chemical class, was detected in the resistant population. Pre-treatment with an inhibitor of cytochrome P450 reduced the level of iodosulfuron resistance to 46-fold in the resistant population, suggesting enhanced herbicide metabolism, a non-target site mechanism, contributed to resistance of this herbicide. In addition, a proline to leucine substitution at codon 197 was detected, suggesting a target-site-based mechanism was also associated with resistance to iodosulfuron. This is the first report on the resistance mechanisms to ALS-inhibiting herbicides identified in Lolium perenne in New Zealand and highlights the importance of integrated weed management approaches to reduce the likelihood of ALS-inhibitor herbicide resistance becoming more widespread. [ABSTRACT FROM AUTHOR]

Corn (Zea mays L.) is one of the most important cereals worldwide. To maintain crop productivity, it is important to eliminate weeds that compete for nutrients and other resources. The eradication of these causes environmental problems through the use of agrochemicals. The implementation of technology to mitigate this impact is also a challenge. In this work, an artificial vision system was implemented based on the YOLOv5s (You Only Look Once) model, which uses a single convolutional neural network (CNN) that allows differentiating corn from four types of weeds, for which a mobile support structure was built to capture images. The performance of the trained model had a value of mAP@05 (mean Average Precision) at a threshold of 0.5 of 83.6%. A prediction accuracy of 97% and a mAP@05 of 97.5% were obtained for the maize class. For the weed classes, Lolium perenne, Sonchus oleraceus, Solanum nigrum, and Poa annua obtained an accuracy of 86%, 90%, 78%, and 74%, and a mAP@05 of 81.5%, 90.2%, 76.6% and 72.0%, respectively. The results are encouraging for the construction of a precision weeding system. [ABSTRACT FROM AUTHOR]

Treatment of plants with mineral-organic concentrates has developed intensively in recent years. Fertilizers containing, among others, humus, L-amino acids, vitamins, chelates and metal complexes, macro-, micro- and meso-elements, organic matter and humic acids from the top organic layer of leonardite coal have a positive effect on plant growth and quality and seed yield. An experiment was conducted between 2019 and 2022 at the University of Agriculture in Kraków, in which the impact of mineral-organic concentrate on the seed yield and quality of perennial ryegrass (Lolium perenne L.) 2N Bokser (Hodowla Roślin Grunwald Ltd. Grupa IHAR, Grunwa, Poland) was determined. As part of the experiment, plants were sprayed with a mineral-organic product in three different doses: 1.0, 2.0 and 3.0 L·ha−1. The following parameters were examined: the number of generative shoots, the length of the flag leaf, seed yield, germination capacity and the weight of one thousand seeds. It turned out that the application of the concentrate with 3 L·ha−1 and 2 L·ha−1 led to a significant increase in the number of generative shoots and in seed yield, compared to control. In addition, seed germination capacity of fertilized plants was higher, with the greatest increase after the application of 3 L·ha−1. Moreover, the average weight of one thousand seeds was significantly higher in fertilized plants, compared to the control, and the largest increase was recorded in response to the highest dose. The results indicated a positive effect of the organic-mineral concentrate on perennial ryegrass development parameters and seed quality. [ABSTRACT FROM AUTHOR]