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A pathogen arriving on a host typically encounters a diverse community of microbes that can shape priority effects, other within-host interactions and infection outcomes. In plants, environmental nutrients can drive trade-offs between host growth and defence and can mediate interactions between co-infecting pathogens. Nutrients may thus alter the outcome of pathogen priority effects for the host, but this possibility has received little experimental investigation. To disentangle the relationship between nutrient availability and co-infection dynamics, we factorially manipulated the nutrient availability and order of arrival of two foliar fungal pathogens (Rhizoctonia solani and Colletotrichum cereale) on the grass tall fescue (Lolium arundinaceum) and tracked disease outcomes. Nutrient addition did not influence infection rates, infection severity or plant biomass. Colletotrichum cereale facilitated R. solani, increasing its infection rate regardless of their order of inoculation. Additionally, simultaneous and C. cereale-first inoculations decreased plant growth and—in plants that did not receive nutrient addition—increased leaf nitrogen concentrations compared to uninoculated plants. These effects were partially, but not completely, explained by the duration and severity of pathogen infections. This study highlights the importance of understanding the intricate associations between the order of pathogen arrival, host nutrient availability and host defence to better predict infection outcomes. [ABSTRACT FROM AUTHOR]

In New Zealand, facial eczema (FE) is a serious health and welfare issue for grazing ruminants caused by ingesting toxic spores of the fungus Pseudopithomyces chartarum.A literature review of research about the effect of pasture plant species, farm management practices and associated environmental factors on FE in New Zealand, was undertaken. An important outcome of this research has been the development of spore count techniques used on-farm to monitor P. chartarum during the summer/autumn risk period. Other research outcomes include: Reduce pasture litter (decaying herbage) by hard spring grazing, with minimal topping, and use pasture species that reduce litter.Avoid hard grazing during the riskiest autumn period.Minimise grazing of perennial ryegrass dominant pastures by increasing legume content or use the less risky species such as tall fescue.Utilise specialist (non-ryegrass) legume and herb-based pastures that provide less litter, are grazed to higher residuals, and provide high-quality feed.Future FE research should focus on the incorporation of ‘high-quality’ FE-safe species, such as tall fescue, legumes and herbs, into existing farming systems. They can enhance feed supply during the summer/autumn FE risk period but require appropriate management guidelines to maximise production and persistence.Reduce pasture litter (decaying herbage) by hard spring grazing, with minimal topping, and use pasture species that reduce litter.Avoid hard grazing during the riskiest autumn period.Minimise grazing of perennial ryegrass dominant pastures by increasing legume content or use the less risky species such as tall fescue.Utilise specialist (non-ryegrass) legume and herb-based pastures that provide less litter, are grazed to higher residuals, and provide high-quality feed. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare the effectiveness of two different grasses offered to weaned beef breed bulls until slaughter. Three cuts of tall fescue (TF) and meadow fescue (MF) were harvested with as similar chemical composition as possible, pre-wilted and ensiled separately in bales. Forty newly weaned intact bulls of Continental beef breeds were kept indoors and randomized to one of the two silages, complemented with 2.5–3.0 kg grain/day, and followed until slaughter. The two silages were offered simultaneously from the same cut during most of the finishing period. Bulls receiving TF had a higher silage dry matter intake than bulls offered MF (7.69 vs. 7.04 kg-d; P = 0.0026) but had lower carcass weight (370 vs. 380 kg; P = 0.0357). From this limited study it was concluded that replacing traditional MF silage with TF silage might compromise the carcass performance of finishing beef bulls. [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]

Plants employ various strategies to mitigate the impact of herbivory and one such strategy involves the associations with fungal endophytes. Some cool‐season forage grasses benefit from protection against herbivores by Epichloë fungal endophytes. However, since the maintenance of symbiosis relies on the plant, costs of hosting endophytes have been also observed. This becomes particularly crucial when forage varieties, inoculated with endophytes that are nontoxic to livestock but still protect host against insect herbivores, experience significant foliage loss (defoliation). We investigated the impact of a nontoxic Epichloë endophyte on the responses of tall fescue plants to defoliation across two morphotype varieties, Continental and Mediterranean, and different seasonal contexts. Under specific defoliation treatments, endophyte‐symbiotic plants showed reduced postdefoliation recovery, indicating the costs of hosting the endophyte for host plants. However, these conditions were not the most severe for plant growth. Regardless of the endophyte's presence, plants from Continental morphotype exhibited superior recovery than those from Mediterranean morphotype, an effect that was more pronounced in summer. Notably, the endophyte promoted plant growth after defoliation in winter for both morphotypes. Our study offers insights into mitigating endophyte‐associated costs on plant recovery postdefoliation by strategically managing cutting intensity and frequency, considering the seasonal variation. [ABSTRACT FROM AUTHOR]

Cover crops between rows in orchards can improve the development of soil resources and increase agricultural productivity. However, there have been few reports of cover crops that can act as a "green manure" in apple orchards across arid and semiarid zones. This study investigated the effects of planting interrow vegetation on soil properties and apple tree performance during a 32-month experiment. There were six treatments: clean cultivation as a control; natural grass planting; planting with ryegrass; planting with alfalfa; planting with tall fescue; and planting with villous wild pea cover crops. The treatments primarily affected the 0- to 20-cm surface soil layer. Soil carbon, nitrogen, and enzyme levels initially decreased (during the first 12-24 months); then, they increased (24-32 months). The cover crops significantly increased nutrient contents (soluble organic carbon, microbial carbon and nitrogen, alkaline dissolved nitrogen, nitrate nitrogen, and ammonium nitrogen) in the 0- to 20-cm soil layer by more than 19.6% and increased the related enzyme activities by more than 25.2%. The alfalfa and wild pea alleys had a stronger effect on the soil environment than the control, natural grass, ryegrass, and tall fescue alley treatments; however, after 32 months, the alfalfa treatment inhibited fruit tree growth and development. This was unexpected because alfalfa seemed to have a positive effect on soil fertility characteristics. Under local ecological conditions, villous wild pea had the greatest effect on apple orchard productivity and significantly increased short branching by 15.9%, fruit weight per fruit by 12.6%, yield per plant by 8.6%, and soluble sugar content by 10.5% compared with clean cultivation. The correlation analysis showed that there were significant or highly significant positive correlations between fruit tree performance and soil carbon, nitrogen, and enzyme activity levels as the soil layer depth increased. Therefore, under local ecological conditions, cover crops have a greater effect on orchard surface soil fertility than on deeper soils, and intercropping with villous wild pea potentially produces the greatest improvement in apple orchard productivity. [ABSTRACT FROM AUTHOR]

To assess the biocontrol potential of Nigrospora oryzae against Solanum rostratum, the effects of different medium components and fermentation conditions on the biomass of N. oryzae were investigated to determine the optimal medium composition and fermentation conditions. Subsequently, the pathogenicity of S. rostratum increased after artificial inoculation of S. rostratum with N. oryzae. Additionally, the safety of N. oryzae fermentation on seven crops were evaluated. The results revealed that the optimal shake flask culture ratio for N. oryzae was lactose:glycerol:yeast extract:(NH4)2SO4 = 2:2:1:2. The optimal fermentation conditions were as follows: 15 mL of inoculum, 75 mL of fermentation liquid in a 150 mL shake flask, an initial pH of 5.0, a culture temperature of 20 °C, and 4 days of culture. The disease index of S. rostratum after spraying with N. oryzae fermentation agent was 60.00, indicating strong pathogenicity to S. rostratum. Safety evaluation revealed that N. oryzae exhibited no symptoms on Zea mays, S. melongena, Festuca arundinacea, Bromus inermis, or Medicago sativa but showed moderate susceptibility to Triticum aestivum and S. lycopersicum. This study represents the first exploration of the biocontrol potential of N. oryzae against S. rostratum. These findings suggest the potential of N. oryzae for development as a microbial herbicide targeting S. rostratum. [ABSTRACT FROM AUTHOR]

Functional traits are powerful tools for distinguishing between plants with different resource acquisition strategies. Fast-growing plants normally dominate resource-rich habitats and present trait values associated with high productivity, such as high specific leaf area (SLA), short leaf lifespan, and rapid leaf elongation rate (LER). In contrast, slow-growing species have a higher leaf weight ratio (LWR), leaf lifespan (LLS), and phyllochron, which are useful traits for survival in stressful and unfertile environments, but are normally thought to be incompatible with high productivity, even under fertile conditions. We tested the hypothesis that slow-growing forage grasses have demographic parameters (tiller population density and canopy density) that offset their slow individual traits, making them as productive as fast-growing species when grown in fertile soil. Species with contrasting growth strategies (Arrhenatherum elatius L. and Festuca arundinacea Schreb cv. Quantum II, fast and slow-growing species, respectively) were cultivated in 45 m2 field plots and subjected to the same cutting regime and nitrogen supply level. Functional traits and canopy attributes were continuously measured during 8 growing cycles after the establishment of the swards. A. elatius had higher SLA, LER, leaf senescence, and leaf appearance rates, whereas F. arundinacea had higher LLS and LWR values. Conversely, there were no differences in relative growth rate or forage accumulation. F. arundinacea was able to offset their plant functional traits, typically associated with slow-growing grasses, with some demographic parameter like higher tiller population density, allowing it to be as productive as the fast-growing A. elatius when both were grown in fertile soil. Therefore, we suggest cautionary use of traditional plant functional traits to explain and predict the annual productivity of slow-growing grasses. [ABSTRACT FROM AUTHOR]

The objective of our study was to evaluate the effect of endophyte-infected tall fescue (E+) seeds intake on liver tissue transcriptome in growing Angus × Simmental steers and heifers through RNA-seq analysis. Normal weaned calves (~8 months old) received either endophyte-free tall fescue (E-; n = 3) or infected tall fescue (E+; n = 6) seeds for a 30-d period. The diet offered was ad libitum bermudagrass (Cynodon dactylon) hay combined with a nutritional supplement of 1.61 kg (DM basis) of E+ or E- tall fescue seeds, and 1.61 kg (DM basis) of energy/protein supplement pellets for a 30-d period. Dietary E+ tall fescue seeds were included in a rate of 20 μg of ergovaline/kg BW/day. Liver tissue was individually obtained through biopsy at d 30. After preparation and processing of the liver samples for RNA sequencing, we detected that several metabolic pathways were activated (i.e., upregulated) by the consumption of E+ tall fescue. Among them, oxidative phosphorylation, ribosome biogenesis, protein processing in endoplasmic reticulum and apoptosis, suggesting an active mechanism to cope against impairment in normal liver function. Interestingly, hepatic protein synthesis might increase due to E+ consumption. In addition, there was upregulation of "thermogenesis" KEGG pathway, showing a possible increase in energy expenditure in liver tissue due to consumption of E+ diet. Therefore, results from our study expand the current knowledge related to liver metabolism of growing beef cattle under tall fescue toxicosis. [ABSTRACT FROM AUTHOR]

Grasses hosting Epichloë endophytes are protected against herbivores due to the production of various fungal alkaloids. Previous research has found that high foliar phosphorus concentrations reduce the level of the alkaloid ergovaline, thereby reducing the endophyte‐mediated herbivore resistance. Yet, the impact of phosphorus on ergovaline biosynthesis versus its influence on endophyte growth and synthesis of other fungal alkaloids remains unresolved. Our objective was to elucidate these relationships. We grew endophyte‐symbiotic and non‐symbiotic Festuca arundinacea plants and fertilised them with different doses of phosphorus. Later, half of the plants from each treatment were challenged with larvae of the generalist chewing insect Spodoptera frugiperda. We assessed the relationships between foliar phosphorus levels, fungal mycelium and alkaloid concentrations, as well as their impacts on larvae performance, herbivore‐caused damage and plant biomass. Endophyte mycelial biomass in plant tissue was found to be independent of foliar phosphorus concentration. The alkaloids lolines and peramine showed a linear relationship with mycelial biomass but no correlation with foliar phosphorus. Surprisingly, high ergovaline concentrations were positively associated with an interaction between endophyte mycelial biomass and foliar phosphorus concentration. Although herbivory increased loline concentration, only high concentrations of ergovaline and peramine were related to reduced S. frugiperda larvae weight gain. However, endophyte presence did not reduce herbivory damage on plants. Contrary to expectation, we did not find a negative but a positive association between concentrations of foliar phosphorus and ergovaline alkaloid, through its interaction with endophyte mycelial biomass. Alternatively, our findings suggest that phosphorus plays a crucial role in modulating the Epichloë‐mediated defensive mutualism, primarily through its effects on ergovaline rather than on endophyte concentration or production of other alkaloids. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

In order to investigate the effects of brassinolide (BR) on the ecological stoichiometric characteristics and internal stability of plants in slope ecological protection under different drought conditions, the biomass, proline content, nutrient content, and internal stability of tall fescue (Festuca arundinacea) in three stress periods were analyzed by weighing water control method, with three drought degrees (75% ± 5%), mild drought (55% ± 5%) and severe drought (35% ± 5%) and four BR concentrations (0 mg/L, 0.05 mg/L, 0.2 mg/L and 0.5 mg/L). The results showed that drought stress resulted in a decrease in plant biomass and nutrient content, and there were differences in carbon, nitrogen and phosphorus contents and their stoichiometric ratios in different organs. Spraying suitable concentration of BR could alleviate plant nutrient loss and promote nutrient accumulation of the tall fescue. Under normal water spraying conditions 0.2 mg/L, under mild and severe drought conditions with spraying of 0.5 mg/L BR, it is most suitable for the nutrient accumulation in tall fescue. The tall fescue showed high sensitivity to exogenous BR input, and the internal stability of the underground part of the tall fescue increased clearly. BR is propitious to the synthesis of proline and enhances the drought resistance of plants. According to stoichiometric characteristics, BR can improve the nitrogen and phosphorus utilization efficiency of tall fescue to a certain extent, and the results of the nitrogen and phosphorus ratio show that nitrogen is the main factor limiting plant growth in a vegetation concrete ecological restoration system, which can supplement nitrogen to accelerate the process of vegetation restoration. The application of BR can improve the biomass and stress resistance of tall fescue, adjust the nutrient distribution strategy and stoichiometric stability, and alleviate the adverse effects of drought on plants. This study provides new ideas and methods for ecological restoration and vegetation reconstruction in arid areas. [ABSTRACT FROM AUTHOR]

Background: The escalating impacts of global warming intensify the detrimental effects of heat stress on crop growth and yield. Among the earliest and most vulnerable sites of damage is Photosystem II (PSII). Plants exposed to recurring high temperatures develop heat stress memory, a phenomenon that enables them to retain information from previous stress events to better cope with subsequent one. Understanding the components and regulatory networks associated with heat stress memory is crucial for the development of heat-resistant crops. Results: Physiological assays revealed that heat priming (HP) enabled tall fescue to possess higher Photosystem II photochemical activity when subjected to trigger stress. To investigate the underlying mechanisms of heat stress memory, we performed comparative proteomic analyses on tall fescue leaves at S0 (control), R4 (primed), and S5 (triggering), using an integrated approach of Tandem Mass Tag (TMT) labeling and Liquid Chromatography-Mass Spectrometry. A total of 3,851 proteins were detected, with quantitative information available for 3,835 proteins. Among these, we identified 1,423 differentially abundant proteins (DAPs), including 526 proteins that were classified as Heat Stress Memory Proteins (HSMPs). GO and KEGG enrichment analyses revealed that the HSMPs were primarily associated with the "autophagy" in R4 and with "PSII repair", "HSP binding", and "peptidase activity" in S5. Notably, we identified 7 chloroplast-localized HSMPs (HSP21, DJC77, EGY3, LHCA4, LQY1, PSBR and DEGP8, R4/S0 > 1.2, S5/S0 > 1.2), which were considered to be effectors linked to PSII heat stress memory, predominantly in cluster 4. Protein-protein interaction (PPI) analysis indicated that the ubiquitin-proteasome system, with key nodes at UPL3, RAD23b, and UCH3, might play a role in the selective retention of memory effectors in the R4 stage. Furthermore, we conducted RT-qPCR validation on 12 genes, and the results showed that in comparison to the S5 stage, the R4 stage exhibited reduced consistency between transcript and protein levels, providing additional evidence for post-transcriptional regulation in R4. Conclusions: These findings provide valuable insights into the establishment of heat stress memory under recurring high-temperature episodes and offer a conceptual framework for breeding thermotolerant crops with improved PSII functionality. [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]

Cool season grasses, including tall fescue, are dominant plants within managed grassland systems. A symbiotic relationship between tall fescue (Lolium arundinaceum) and the fungal endophyte Epichloë coenophiala can affect grassland response to perturbations, including changing rainfall patterns and increasing temperatures associated with climate change. Because E. coenophiala reproduces asexually, there is concern that climate change may negatively impact vertical transmission, resulting in subsequent fescue stands with lower infection frequencies and reduced grassland resiliency. This 3-year field study evaluated the impact of increased temperature, altered precipitation, and their combination on vertical transmission, seed number, and seed weight in tall fescue clones containing common toxic (CTE) or novel nonmammalian toxic (NTE) E. coenophiala. NTE clones exhibited greater transmission than CTE clones. Temperature did not affect transmission, but altered precipitation reduced transmission in CTE clones. On average, NTE clones responded to increased temperatures by reducing seed number, while CTE clones responded oppositely. NTE clones produced seeds of similar masses across all growing years, suggesting greater stability under varying environmental conditions. Our work illustrates that both plant and endophyte genetics influence vertical transmission and that climate change is unlikely to significantly impact endophyte transmission in the southeastern transition zone of the United States. [Graphic: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Abstract Background The escalating impacts of global warming intensify the detrimental effects of heat stress on crop growth and yield. Among the earliest and most vulnerable sites of damage is Photosystem II (PSII). Plants exposed to recurring high temperatures develop heat stress memory, a phenomenon that enables them to retain information from previous stress events to better cope with subsequent one. Understanding the components and regulatory networks associated with heat stress memory is crucial for the development of heat-resistant crops. Results Physiological assays revealed that heat priming (HP) enabled tall fescue to possess higher Photosystem II photochemical activity when subjected to trigger stress. To investigate the underlying mechanisms of heat stress memory, we performed comparative proteomic analyses on tall fescue leaves at S0 (control), R4 (primed), and S5 (triggering), using an integrated approach of Tandem Mass Tag (TMT) labeling and Liquid Chromatography-Mass Spectrometry. A total of 3,851 proteins were detected, with quantitative information available for 3,835 proteins. Among these, we identified 1,423 differentially abundant proteins (DAPs), including 526 proteins that were classified as Heat Stress Memory Proteins (HSMPs). GO and KEGG enrichment analyses revealed that the HSMPs were primarily associated with the “autophagy” in R4 and with “PSII repair”, “HSP binding”, and “peptidase activity” in S5. Notably, we identified 7 chloroplast-localized HSMPs (HSP21, DJC77, EGY3, LHCA4, LQY1, PSBR and DEGP8, R4/S0 > 1.2, S5/S0 > 1.2), which were considered to be effectors linked to PSII heat stress memory, predominantly in cluster 4. Protein-protein interaction (PPI) analysis indicated that the ubiquitin-proteasome system, with key nodes at UPL3, RAD23b, and UCH3, might play a role in the selective retention of memory effectors in the R4 stage. Furthermore, we conducted RT-qPCR validation on 12 genes, and the results showed that in comparison to the S5 stage, the R4 stage exhibited reduced consistency between transcript and protein levels, providing additional evidence for post-transcriptional regulation in R4. Conclusions These findings provide valuable insights into the establishment of heat stress memory under recurring high-temperature episodes and offer a conceptual framework for breeding thermotolerant crops with improved PSII functionality.

The subterranean sod webworm, also known as cranberry girdler (Chrysoteuchia topiaria), is one of the most damaging insect pests in cool‐season grass grown for seed crops in Oregon. Chemical control options are limited and require irrigation or rainfall for adequate insecticide incorporation to control C. topiaria larvae. Epichloë endophytes associated with cool‐season turfgrass species and their mycotoxin profiles are well‐documented in offering plant protection against invertebrates; these fungi may offer sustainable pest management tools. Our objectives were to characterize endophyte‐mediated resistance to C. topiaria in 19 commercially available cultivars of tall fescue, perennial ryegrass, and fine fescue grown for seed in Oregon. Endophyte status (presence and viability) of fungal endophytes and their mycotoxin profiles were measured using polymerase chain reaction, and liquid chromatography‐tandem mass spectrometry, respectively. No‐choice assays were conducted in the laboratory to measure the impact of endophyte status on C. topiaria larvae in two separate no‐choice experiments. Our results suggested that increased mortality of C. topiaria larvae (R2 = 0.8526, Experiment 1; R2 = 0.6628, Experiment 2) in tall fescue cultivars was most influenced by total peramine and ergot alkaloid, and total ergoline concentrations in Experiment 1 and 2, respectively. However, no significant effect on insect mortality was found in the perennial ryegrass and fine fescue cultivars included in this study. Overall, these findings suggest a viable grass–endophyte association can be utilized as a sustainable alternative to foliar insecticides for C. topiaria management in tall fescue seed crops. Plain Language Summary: This is an applied research article. This study explored the endophyte status of 19 commercially available cultivars of three cool‐season grass species. Two experiments were conducted in which insect response was measured regarding mortality after 7–10 days of feeding on each cultivar. We found that increased mortality occurred in endophyte‐infected tall fescue cultivars. Furthermore, the insect resistance response was also found to be associated with the production of mycotoxins in these cultivars. [ABSTRACT FROM AUTHOR]

To explore cost-effective and efficient phytoremediation strategies, this study investigated the distinct roles of earthworm activity and mucus in enhancing Cd phytoextraction from soils contaminated by Festuca arundinacea, focusing on the comparative advantages of selective leaf harvesting versus traditional whole-plant harvesting methods. Our study employed a horticultural trial to explore how earthworm activity and mucus affect Festuca arundinacea' s Cd phytoremediation in soils using control, earthworm, and mucus treatments to examine their respective effects on plant growth and Cd distribution. Earthworm activity increased the dry weight of leaves by 13.5% and significantly increased the dry weights of declining and senescent leaves, surpassing that of the control by more than 40%. Earthworm mucus had a similar, albeit less pronounced, effect on plant growth than earthworm activity. This study not only validated the significant role of earthworm activity in enhancing Cd phytoextraction by Festuca arundinacea, with earthworm activity leading to over 85% of Cd being allocated to senescent tissues that comprise only approximately 20% of the plant biomass, but also highlighted a sustainable and cost-effective approach to phytoremediation by emphasizing selective leaf harvesting supported by earthworm activity. By demonstrating that earthworm mucus alone can redistribute Cd with less efficiency compared to live earthworms, our findings offer practical insights into optimizing phytoremediation strategies and underscore the need for further research into the synergistic effects of biological agents in soil remediation processes. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal inoculation can promote plant growth, but specific research on the difference in the symbiosis effect of arbuscular mycorrhizal fungi and plant combination is not yet in-depth. Therefore, this study selected Medicago sativa L., Bromus inermis Leyss, and Festuca arundinacea Schreb., which were commonly used for restoring degraded land in China to inoculate with three AMF separately, to explore the effects of different AMF inoculation on the growth performance and nutrient absorption of different plants and to provide a scientific basis for the research and development of the combination of mycorrhiza and plants. We set up four treatments with inoculation Entrophospora etunicata (EE), Funneliformis mosseae (FM), Rhizophagus intraradices (RI), and non-inoculation. The main research findings are as follows: the three AMF formed a good symbiotic relationship with the three grassland plants, with RI and FM having more significant inoculation effects on plant height, biomass, and tiller number. Compared with C, the aboveground biomass of Medicago sativa L., Bromus inermis Leyss, and Festuca arundinacea Schreb. inoculated with AMF increased by 101.30–174.29%, 51.67–74.14%, and 110.67–174.67%. AMF inoculation enhanced the plant uptake of N, P, and K, and plant P and K contents were significantly correlated with plant biomass. PLS-PM analyses of three plants all showed that AMF inoculation increased plant nutrient uptake and then increased aboveground biomass and underground biomass by increasing plant height and root tillering. This study showed that RI was a more suitable AMF for combination with grassland degradation restoration grass species and proposed the potential mechanism of AMF–plant symbiosis to increase yield. [ABSTRACT FROM AUTHOR]

Background: Although RNA-seq data are traditionally used for quantifying gene expression levels, the same data could be useful in an integrated approach to compute genetic distances as well. Challenges to using mRNA sequences for computing genetic distances include the relatively high conservation of coding sequences and the presence of paralogous and, in some species, homeologous genes. Results: We developed a new computational method, RNA-clique, for calculating genetic distances using assembled RNA-seq data and assessed the efficacy of the method using biological and simulated data. The method employs reciprocal BLASTn followed by graph-based filtering to ensure that only orthologous genes are compared. Each vertex in the graph constructed for filtering represents a gene in a specific sample under comparison, and an edge connects a pair of vertices if the genes they represent are best matches for each other in their respective samples. The distance computation is a function of the BLAST alignment statistics and the constructed graph and incorporates only those genes that are present in some complete connected component of this graph. As a biological testbed we used RNA-seq data of tall fescue (Lolium arundinaceum), an allohexaploid plant ( 2 n = 14 Gb ), and bluehead wrasse (Thalassoma bifasciatum), a teleost fish. RNA-clique reliably distinguished individual tall fescue plants by genotype and distinguished bluehead wrasse RNA-seq samples by individual. In tests with simulated RNA-seq data, the ground truth phylogeny was accurately recovered from the computed distances. Moreover, tests of the algorithm parameters indicated that, even with stringent filtering for orthologs, sufficient sequence data were retained for the distance computations. Although comparisons with an alternative method revealed that RNA-clique has relatively high time and memory requirements, the comparisons also showed that RNA-clique's results were at least as reliable as the alternative's for tall fescue data and were much more reliable for the bluehead wrasse data. Conclusion: Results of this work indicate that RNA-clique works well as a way of deriving genetic distances from RNA-seq data, thus providing a methodological integration of functional and genetic diversity studies. [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]

Background and aims: The introduction of ley in cropping systems can provide multiple services, including high quality forage production and C and N inputs into arable soils. Little is known about the dynamics of these services in degrading grassland and the extent to which trade-offs regarding the use of fixed N for either forage production or as a source of N in the rotation can be found. Methods: A six-year field experiment compared the performance of an alfalfa-tall fescue (A-FE) mixture versus the single species alone (A, FE) in terms of forage production, forage quality and root biomass available as residues for the following crop. N mineralisation potential was then simulated for different grassland destruction scenarios using the STICS model. Result: The forage production, proportion of legumes, and forage quality all declined in the A-FE mixture after year 3 to reach less than 7 T.ha−1 and 20% legume in year 6. The yield advantage of A-FE compared to monospecific grasslands increased over time and was strongly associated with greater species complementarity, resulting from higher N transfer to grasses and increased asynchrony in the seasonal growth of A and FE. Root residue quantities and the potential for N supply to the rotation were not reduced when a degraded legume proportion was reached. Conclusion: The advantage of A-FE mixture over monospecific stands was greater integrated over a long period of time. No major risk of losing the N legacy effect by delaying mixture destruction was detected up to the first year after a sharp legume decline. [ABSTRACT FROM AUTHOR]

Fruit fly ground-dwelling stages (late third instar larvae, pupae, and teneral adults) are susceptible to predation from generalist ground-dwelling predators and to infection by entomopathogenic fungi (EPF). The effect of predators can be enhanced with cover crops and that of EPF by augmentative releases. However, whether these two biological control methods could be combined has not been studied under field conditions yet. Here, we studied in the field whether the enhanced activity of predators against the medfly, Ceratitis capitata, already observed in a Lolium arundinaceum ground cover could be impaired by a soil application of Metarhizium brunneum. Our results show that C. capitata adult emergence was reduced by this EPF for up to three months after fungal application, with the combination of the cover and M. brunneum being the most effective at reducing C. capitata emergence relative to bare soil (92.5% reduction). Although M. brunneum reduced the activity density of ground-dwelling predatory beetles up to 93 days after application, it showed no clear negative effects on earwigs, no effects on spiders, and a positive effect on ants up to 65 days after application. Therefore, the combined use of a ground cover of L. arundinaceum and M. brunneum against the soil-dwelling stages of C. capitata seems to work synergistically and appears as a strong and sustainable control tactic against the medfly and other fruit orchard pests. [ABSTRACT FROM AUTHOR]

Background: Genotype × environment interaction (GEI) slows genetic gains and complicates selection decisions in plant breeding programs. Forage breeding program seed sales often encompass large geographic regions to which the cultivars may not be adapted. An understanding of the extent of GEI in perennial, cool‐season forage grasses will facilitate improved selection decisions and end‐use in areas with harsh winters. Methods: We evaluated the dry matter yield of nine meadow brome (Bromus biebersteinii Roemer & J. A. Schultes), nine orchardgrass (Dactylis glomerata L.), seven tall fescue (Lolium arundinaceum (Schreb.) Darbysh.), and 10 timothy (Phleum pratense L.) cultivars or breeding populations at seven high latitude and/or elevation locations in Canada and the United States from 2019 to 2021. Results: For each of the species, we found significant differences among the genotypes for dry matter yield across environments and found significant levels of GEI. Using site regression analysis and GGE biplot visualizations, we then characterized the extent of the interactions in each species. Except for tall fescue, there was little evidence for the broad adaptation of genotypes across locations. Conclusions: This research adds further evidence to the limitations of perennial, forage breeding programs to develop widely adapted cultivars and the need to maintain regional breeding efforts. [ABSTRACT FROM AUTHOR]

Turfgrasses are essential landscape plants with social, environmental, and aesthetic services for urban ecosystems. However, more is needed to know how to establish them so that they can benefit from their ecosystem services in urban environments. This research examined some quality and morphological and physiological factors for the establishment and social and environmental service assessment of three warm-season turfgrasses, including Kikuyu grass (Pennisetum clandestinum), bermuda grass (Cynodon dactylon), and buffalo grass (Buchloe dactyloides), compared to the cool-season grass of tall fescue (Festuca arundinacea Schreb.). The experiment was split-plot in time, based on a randomized complete block design with eight replications. The main plot was the season with four levels, and the subplot was the four turfgrass species types. The results indicated that seasons and turfgrass types and their interaction significantly impacted most measured variables (p ≤ 0.01). Some quality measurements like turf density, color, texture, coverage, and quality after clipping and establishment confirmed the superiority of Buchloe dactyloides over the other species. Also, kikuyu grass showed higher turfgrass density, more potential for weed control, and higher coverage and growth rate but also showed invasiveness features. Tall fescue had the lowest visual aesthetic compared with the other turfgrass species. Warm-season turfgrasses adaptable to the ecology of the region should be used compared to tall fescue to achieve better turfgrass quality and social and ecosystem services for the sustainable development of arid urban environments. [ABSTRACT FROM AUTHOR]

Soil inundation frequency and intensity in the central United States are predicted to increase because of climate change. Soil inundation is expected to negatively affect plant growth and persistency. Our objective was to measure tiller and apical meristem height, leaf area index (LAI), and leaf‐to‐stem ratio effects on tall fescue (Schedonorus arundinaceus (Schreb.)) under different levels of soil inundation intensity. The study was conducted on a commercial farm in northwestern Ohio, from spring to fall 2021. Three different levels of inundation were observed and assigned as treatments: no inundation, low inundation (LI), and high inundation (HI). LI and HI were defined by the duration on which the soil was inundated after heavy rain events: 1–2 and 3–5 days after rain, respectively. Meristem and tiller height were higher during spring (p < 0.001), and lower in late summer across treatments (p < 0.001). The higher LAI and leaf‐to‐stem ratio occurred in spring, probably due to higher leaf mass (p < 0.001). As seasons progressed, plant and meristem height, LAI, and leaf mass decreased (p < 0.001). Despite not being considered an inundation‐tolerant species, tall fescue showed morphological adaptation to the inundation levels of our study, suggesting that this species can be used to manage fields prone to short‐term inundation. Core Ideas: Tall fescue meristem and tiller height increased in response to inundation intensity.Inundation resulted in higher stem mass but leaf proportion remained stable.Tall fescue showed morphological adaptation to persist the short‐term inundation events. [ABSTRACT FROM AUTHOR]

Contamination of soil and water with petroleum hydrocarbons and metals can pose a significant threat to the environment and human health. This study aimed to investigate the establishment and growth of tall fescue and agropyron in two petroleum-contaminated soils (soil S1 and soil S2) with previous landfarming treatments, and to assess the phytoremediation potential for heavy metal removal from these polluted soils. The results showed that the presence of petroleum hydrocarbons significantly (P < 0.05) reduced plant growth, but plant development was facilitated in soils with prior landfarming treatments. Urease activity in the rhizosphere of agropyron for soil S1 was about 47% higher than the unplanted control soil. The rhizosphere of agropyron and tall fescue eliminated more than 40% and 20% of total hydrocarbon amounts in soil S1, respectively, compared to the unplanted soil. Moreover, the plants grown in the landfarming treatment exhibited higher concentrations of metals (Fe, Zn, Mn, Cu, and Ni) than the control. Based on the findings, the combination of landfarming and phytoremediation techniques can provide an optimal solution for removing mixed pollutants, including petroleum hydrocarbons and metals, from the environment. [ABSTRACT FROM AUTHOR]

Many cool-season pastures in the southeastern U.S. are dominated by a competitive cool-season grass, tall fescue (Schedonorus arundinaceus), and lack substantial plant diversity. Planting native warm-season grasses (NWSGs) and wildflowers (WFs) into these pastures could provide summer forage for cattle and more floral resources for pollinators. This paper summarizes field experiments designed to evaluate different spatiotemporal planting arrangements of NWSGs and WFs to improve their establishment success. The study was conducted from April 2021 to October 2023 in central Virginia (USA). Planting treatments included NWSG and WF mixtures planted: (1) together in the same space, (2) spatially separated in space (i.e., side by side), or (3) temporally separated where NWSGs and WFs were planted in difference sequences. Results showed few differences in forage mass, floral production, and botanical composition as well as stand density in 2021 and 2022. In 2023, NWSG abundance was greater where grasses were planted first or mixed with WFs. Similarly, the WF component was favored when they were planted before NWSGs. Overall, planting NWSG and WF mixes separately, either spatially or temporally, favors successful establishment and could offer more flexibility for using selective herbicides to suppress the heavy weed pressure that often accompanies these plantings. [ABSTRACT FROM AUTHOR]

Canopy temperature provides valuable information for efficient irrigation management and for detecting drought injury in a fast and non-destructive way. It also helps quantify the trade-offs between water conservation and the cooling benefit of the irrigated urban landscape, a critical issue in semiarid inland southern California with limited available water resources. Two adjacent hybrid bermudagrass and tall fescue irrigation trials were conducted to determine canopy temperature changes under a wide range of irrigation treatments from 2017 to 2019 in Riverside, California, USA. The canopy temperature data were also used to develop an empirical crop water stress index (CWSI) for each species. The CWSI values ranged from -0.15 to 0.71 for tall fescue and from -0.28 to 0.54 for hybrid bermudagrass. We observed a moderate correlation between visual rating scores (VR) and CWSI values for tall fescue (r = -0.68) and hybrid bermudagrass (r = -0.61). The fitted linear regression between VR and CWSI data suggested CWSI thresholds close to zero for both species to maintain their acceptable visual quality. The irrigation level consistently showed a significant effect on canopy temperature for both species. On average, a 10% decrease in irrigation application increased the canopy temperature of tall fescue and hybrid bermudagrass by 1.3°C and 0.9°C, respectively. Therefore, deficit irrigation might reduce the cooling benefits of irrigated urban lawns in the semiarid climate of inland southern California. [ABSTRACT FROM AUTHOR]

Tall fescue (Festuca arundinacea Schreb.) is a perennial C3 grass species usually associated with the endophyte fungus Epichloë coenophiala that enhances tolerance to biotic and abiotic stresses. Given that the proportion of infected tall fescue plants in the grasslands of the Flooding Pampa (Argentina) has been progressively increasing, it is proposed that endophytes confer tolerance to the stresses characteristic of that environment, especially flooding. Plants from a naturalized population and a commercial cultivar were grown, both with and without endophyte (wild type and AR584 respectively). The plants were subjected to two submergence treatments (i.e., control and partial submergence) in two development stages (5‐leaf stage and beginning of the elongation of internodes). Plant performance (aerial and root biomass, root aerenchyma formation, total root length and root diameter, proportion of reproductive tillers, number of panicles and seeds produced) and endophyte transmission to progeny were evaluated. Endophytes did not alter the ecological fitness of plants under partial submergence. Independently of the water condition, the symbiosis was linked to low biomass in plants from the naturalized population, while the opposite occurred in plants from the cultivar. Partial submergence did not affect the germination of the seeds produced, nor the transmission of the endophyte to the seedlings that originated from them. Our work suggests that the invasion ability of tall fescue in the Flooding Pampa grasslands is not related to an endophyte‐mediated improvement of plants to tolerate water excess. [ABSTRACT FROM AUTHOR]

Drought stress significantly hampers plant growth and productivity. Strigolactones (SLs), a class of carotenoid-derived plant hormones, are recognized for their pivotal role in modulating plant morphology and enhancing drought resistance. Nonetheless, the underlying mechanisms through which SLs influence drought tolerance in tall fescue remain largely unexplored. In this study, we employed TIS108 to inhibit SL biosynthesis under drought conditions and assessed a range of morphological and physiological parameters in tall fescue, including biomass both above and below ground, antioxidase activities, proline and soluble sugar contents, and survival rates, across treatments of drought and drought coupled with TIS108 inhibition. Our findings demonstrate that the suppression of SL synthesis detrimentally affects the drought resilience of tall fescue. Through comprehensive transcriptome sequencing and subsequent qRT-PCR analyses of samples subjected to drought with and without TIS108 treatment, we identified a marked downregulation of genes involved in auxin metabolism and root development. This downregulation correlated with significant reductions in total root length, root surface area, and the number of root tips under drought stress conditions. Collectively, our research elucidates that the inhibition of SL synthesis impairs drought tolerance in tall fescue by constraining root growth and development, mediated through the modulation of auxin metabolism. [ABSTRACT FROM AUTHOR]

Background and Aims In the subfamily Poöideae (Poaceae), certain grass species possess anti-herbivore alkaloids synthesized by fungal endophytes that belong to the genus Epichloë (Clavicipitaceae). The protective role of these symbiotic endophytes can vary, depending on alkaloid concentrations within specific plant–endophyte associations and plant parts. Methods We conducted a literature review to identify articles containing alkaloid concentration data for various plant parts in six important pasture species, Lolium arundinaceum , Lolium perenne , Lolium pratense , Lolium multiflorum | Lolium rigidum and Festuca rubra , associated with their common endophytes. We considered the alkaloids lolines (1-aminopyrrolizidines), peramine (pyrrolopyrazines), ergovaline (ergot alkaloids) and lolitrem B (indole-diterpenes). While all these alkaloids have shown bioactivity against insect herbivores, ergovaline and lolitrem B are harmful for mammals. Key Results Loline alkaloid levels were higher in the perennial grasses L. pratense and L. arundinaceum compared to the annual species L. multiflorum and L. rigidum , and higher in reproductive tissues than in vegetative structures. This is probably due to the greater biomass accumulation in perennial species that can result in higher endophyte mycelial biomass. Peramine concentrations were higher in L. perenne than in L. arundinaceum and not affected by plant part. This can be attributed to the high within-plant mobility of peramine. Ergovaline and lolitrem B, both hydrophobic compounds, were associated with plant parts where fungal mycelium is usually present, and their concentrations were higher in plant reproductive tissues. Only loline alkaloid data were sufficient for below-ground tissue analyses and concentrations were lower than in above-ground parts. Conclusions Our study provides a comprehensive synthesis of fungal alkaloid variation across host grasses and plant parts, essential for understanding the endophyte-conferred defence extent. The patterns can be understood by considering endophyte growth within the plant and alkaloid mobility. Our study identifies research gaps, including the limited documentation of alkaloid presence in roots and the need to investigate the influence of different environmental conditions. [ABSTRACT FROM AUTHOR]

The influences of legume diversification on soil carbon (C) pools and sequestration, particularly in Himalayan pastureland, remain poorly understood. Moreover, the impact of legume diversification activities and the stoichiometry of soil enzymes in C biogeochemistry at the ecosystem level remains largely overlooked. The purpose of this study is to investigate the influences of legume diversification on activities and the stoichiometry of soil enzymes and their control of C sequestration in pasturelands. Four experimental fertilized species combinations, namely, SG (50% Festuca arundinacea + 50% Dactylis glomerata), SGL1 (25% Festuca arundinacea + 25% Dactylis glomerata + 50% Onobrychis viciifolia), SGL2 (25% Festuca arundinacea + 25% Dactylis glomerata + 50% Trifolium pratense), SGL12 (25% Festuca arundinacea + 25% Dactylis glomerata + 25% Onobrychis viciifolia + 25% Trifolium pratense), and natural pasture (NG) were compared. Soils under SGL1, SGL2, and SG12 had ~18, 36, and 22% greater soil C than SG, respectively. Among the pastures with fertilization, the C mineralization was suppressed by legume diversification. C sequestration under SGL1, SGL2, and SG12 was ~27, 22, and 38% higher than SG, respectively, at the 0–30 cm soil layer. The ratios of DHA are as follows: for PhOX and DHA, PerOX significantly decreased with an increasing grass–legume mixture, suggesting greater C sequestration. PCA analysis revealed that C sequestration under legume diversification and enzymatic stoichiometry had an indirect but substantial impact on C sequestration. The increasing C sequestration under SGL12 was complemented by higher productivity. Data suggested that increasing legumes in pastureland might greatly enhance ecosystem functions such as soil C storage, productivity, ecorestoration efficiency, and biological activity in Indian Himalayan pastureland. [ABSTRACT FROM AUTHOR]

There is a balance between DM yield and feed value when choosing types of grasses on a farm depending on the acreages of farmland and types of ruminants to be fed. Therefore, optimisation of the harvest strategy for grass silage is important for profitable dairy farming. Tall fescue has high DM yield and can replace traditional grasses, such as timothy, in Northern Europe in a changing climate as it has been shown to be more drought tolerant. As differences in climate responses previously have been related to differences in cell wall structure between grass species and, consequently, in digestibility, it is highly relevant to compare these species at similar maturity stages and to investigate if a very early harvest date will diminish potential differences between the species. This study evaluated the effects of harvest date and forage species on the concentration of hydroxycinnamic acids in silages and its relationship to feed efficiency of dairy cows. Tall fescue and timothy were harvested at very early date on May 25 or at early date on May 31 in the spring growth cycle. Forty lactating dairy cows were used in a block design. Cows received 1 of 4 treatments: (1) tall fescue harvested at very early date, (2) timothy harvested at very early date, (3) tall fescue harvested at early date, and (4) timothy harvested at early date. Diets were formulated to have the same forage-to-concentrate ratio (49:51 on DM basis). Tall fescue silages showed greater concentrations of DM, ash, and CP than timothy silages. Grasses harvested at early date showed greater concentrations of NDF, ADL, and cell wall than grasses harvested at very early date. Tall fescue silages showed greater concentration of p-coumaric acid and lower in vitro organic matter digestibility (IVOMD) compared to timothy silages. Milk production and composition were not affected by treatments but cows fed tall fescue-based diets showed lower milk protein yield and greater milk urea nitrogen than when timothy-based diets were fed. Furthermore, cows receiving timothy-based diets showed greater feed efficiency compared to cows receiving tall fescue-based diets. Thus, the lower concentration of p-coumaric acid and the higher IVOMD was associated with greater feed efficiency of cows fed timothy-based diets compared to tall fescue-based diets.

Purpose: to perform a review of an under-investigated bluegrass crop – tall fescue (Festuca arundinacea Schreb.), which is not widespread in forage production, but has some advantages over other bluegrass grasses. Discussion. Tall fescue is characterized by high seed and forage yields, a long-time growing season, early regrowth in spring, an ability to vegetate until late autumn, and an active regrow capacity. Fescue agrocenoses are responsive to irrigation and a high background of mineral nutrition. The ability to grow on saline and alkalini soils is also important. It is widely used for slope and ravines stabilization. Providing optimal combinations of plant life factors creates conditions for good growth, development and formation of high productivity for a long time as well as allows the crop to persist and prevail in multi-species agrocenoses in a wide variety of soil and climatic conditions – from forest and forest-steppe to steppe and semi-desert regions. Tall fescue grows well in damp places under natural conditions. This moisture-loving plant tolerates moisture-saturated, heavy loamy soils well. Regulation of the water regime of fescue crops ensures a more complete use of the biological potential of the crop, which is expressed in the receipt of two additional mowings, compared to natural moisture conditions. Tall fescue is used mainly in the form of hay, silage and haylage. Conclusion. Cultivation of tall fescue against the background of mineral fertilizer application and irrigation ensures an yield increase on average up to 15 t/ha of dry matter and up to 2.5 t/ha of crude protein collection. The wide distribution of this valuable crop in forage production in arid zones is hampered by the lack of scientifically based rational methods for creating highly productive grass stands and elements of cultivation technology.

Impacts of long‐term fertilization and cultivation were evaluated on nematode communities associated with tall fescue turfgrass following 11 years of treatment applications. Fertilizer treatments of biosolid, synthetic, and plant‐based fertilizers and cultivation treatments of 0×, 1×, and 2× aerification passes were applied to randomized and replicated tall fescue plots at the University of Maryland Paint Branch Turfgrass facility in College Park, Maryland. Free‐living and plant‐parasitic nematodes were identified, enumerated, and categorized into functional groups. Nematode count data were compared using generalized linear mixed modeling with negative binomial distribution and two‐way ANOVA was used to compare nematode ecological indices. Biosolid treatments resulted in lower omnivore‐predator densities than plant‐based fertilizer treatments (p ≤.001) and significantly greater Hoplolaimus densities than plant‐based fertilizer plots (p ≤.05). Synthetic fertilizer applications resulted in the greatest Eucephalobus (p ≤.05) and total bacterivore densities (p ≤.001) of all fertilizer treatments. Plant‐based fertilizer‐treated plots had the largest Maturity Index cp 2‐5 and Structure Index (p ≤.05). Cultivation of 1× resulted in fewer total bacterivore densities than 2× (p ≤.01) while omnivore‐predator densities were greater in 1× than 0× (p ≤.001). Plant health, as measured by NDVI, was lowest in biosolid‐treated turfgrass (p ≤.05). These findings suggest that long‐term turfgrass management practices can have variable impacts on nematode abundance and community structure in tall fescue and provide insights into ecological impacts of turfgrass management practices. [ABSTRACT FROM AUTHOR]

Pasture persistence is a key determinant of the economic and environmental performance of pastoral animal production systems. Large and deep root systems that help resist summer water stress have been proposed as a relevant trait for vegetative persistence of perennial temperate forage species growing in subtropical climates or under future climatically challenging scenarios. In a previous study [Jauregui et al., 2017. Persistence of tall fescue in a subtropical environment: Tiller survival over summer in response to flowering control and nitrogen supply. Grass and Forage Science72, 454–466] we have shown that nitrogen fertilization and grazing management aimed at 'control flowering' increased the survival of tall fescue tillers during harsh summers in Uruguay (lat. 32°S). Here we assessed: (i) to what extent tiller survival is mediated by root system size in spring and (ii) what consequences tiller survival entails for root mass, depth and morphology the following autumn. In two field experiments, significant increases in tiller survival in response to nitrogen fertilization and grazing management (+60% and +80% in 2011/12 and 2012/13, respectively) were not related to concomitant effects on the size or depth of the root system in spring (p >.10). Even when six‐fold within‐treatment variation in root mass was observed, within‐treatment variation in summer tiller survival was little affected (<15%, p =.08). In turn, differences in tiller survival over summer affected little root system characteristics the following autumn. Therefore, we found scant support for the hypothesis that large and deep root systems contribute to survival of tall fescue tillers in this subtropical humid climate. Except for soils with less than 30 mm of plant available water holding capacity, summer water deficits did not induce severe tiller mortality in tall fescue in this climate. [ABSTRACT FROM AUTHOR]

The recombinant sucrose:sucrose 1-fructosyltransferase from Schedonorus arundinaceus (Sa1-SSTrec) produces short-chainfructooligosaccharides (scFOS). In this work, Sa1-SSTrec was covalently or hydrophobic immobilized on Sepabeads® and ReliZyme™ supports. The possible clusters and the parameters related to the immobilization process were predicted by rational design of immobilized derivatives (RDID). Immobilization was performed at pH 7.0 and the three immobilized derivatives with higher experimental enzymatic activity (one of each epoxy-activated, amino-activated and hydrophobic supports: Sepabeads® EC-HFA/S, ReliZyme™ EA403/M and Sepabeads® EC-BU/M, respectively) were selected. The mismatch between some predictions and experimental results were explained by probable limitations of the RDID strategy. The thermodynamic parameters determined at 40, 50 and 60ºC, under not reactive conditions (i.e. in absence of sucrose), showed high thermal stability of Sa1-SSTrec after immobilization on the Sepabeads®EC-HFA/S. Batch experiments with this support, at 45ºC reached similar total scFOS (1-kestotriose and 1,1-kestotetraose) than the soluble enzyme, but scFOS productivity was higher for the immobilized biocatalyst. Operational stability of the immobilized biocatalyst after 4 cycles dropped to about 60% and 25% of its initial value at 30 and 45ºC, respectively, probably by denaturation at these temperatures. The obtained results suggest that the immobilized enzyme could be effectively exploited for industrial production of 1-kestotriose. [Display omitted] • A fructosyltransferase was efficiently immobilized on Sepabeads® and ReliZyme™. • Immobilization was predicted by rational design and compared to practical results. • Immobilization improved thermostability and allowed reusability. • Immobilization opens new opportunities for fructooligosaccharides production. [ABSTRACT FROM AUTHOR]

As urbanization intensifies environmental challenges in contemporary cities, widespread green roof installations emerge as a potential solution. This study explores irrigating tall fescue (Festuca arundinacea Schreb.) turfgrass with saline water in extensive green roof systems, aiming to conserve freshwater resources. The objectives include determining the period of saline water tolerance and identifying the leachate electrical conductivity threshold affecting tall fescue's green coverage. This greenhouse study comprised 24 lysimeters equipped with extensive green roof layering. Treatments included three NaCl irrigation solutions with an electrical conductivity of 3 dS m−1, 6 dS m−1, and 9 dS m−1, while tap water served as the control. Additionally, irrigation treatments were applied at two different regimes, resulting in an average leaching fraction of 0.3 for the low irrigation regime and 0.5 for the high irrigation regime. Tall fescue's tolerance to saline water was evaluated through the determination of green turf cover (GTC) as well as the clipping dry weight and the leachate electrical conductivity (ECL) draining from the lysimeters. It was found that tall fescue turfgrass growing in extensive green roof systems can tolerate irrigation with water of electrical conductivity up to 9 dS m−1 for extended periods, approximating three months, without GTC declining below 90%, provided that a minimum leaching of 30% is maintained. Furthermore, irrigating with water at 9 dS m−1 resulted in a 24.5% reduction in cumulative clipping dry weight over the four-month study period. The regression analysis between GTC and ECL highlighted a substantial decline in GTC when ECL surpassed the critical threshold of 12.5 dS m−1. [ABSTRACT FROM AUTHOR]

The United States is a principal producer of tree nuts (almonds, pistachios, and walnuts), resulting in the generation of excess of tree-nutshell by-products each year, with few market outlets. A nutshell is an essential, lignocellulosic layer that protects a kernel (seed) from the environment during cultivation. The objective of this study was to develop nutshell by-products as herbicide delivery systems, which would not only enable sustainable weed control in fields but also increases nutshell value and reduce the cost of waste disposal. We recently identified a natural salicylaldehyde (SA) that emits volatiles with both herbicidal and antifungal properties. In this study, walnut shell particles saturated with 0.8 to 1.6 M SA were developed as delivery vehicles for SA to soil, which allowed for the controlled release of an SA fumigant for weed control. The pre- and post-emergent herbicidal efficacy of SA was investigated using model monocot (Lolium arundinaceum (Schreb.) Darbysh; turfgrass) and dicot (Brassica rapa var. pekinensis; Chinese cabbage) plants. We compared (1) the effects of different types of solvents for dissolving SA (dimethyl sulfoxide (DMSO) and ethanol (60%, v/v)), and (2) the effect of covering soil with plastic layers (i.e., soil pasteurization) or not covering soil during SA fumigation using nutshells. Results: In the pre-emergent herbicidal testing with the soil covered, the dicot plants exhibited levels of higher susceptibility to SA in DMSO emitted from nutshells when compared to the monocot plants. The seed germination frequencies in the dicots were 15% and 1% with 0.8 and 1.6 M SA, respectively, while those in the monocots were 32% and 18%, respectively, under the same test conditions. In the post-emergent herbicidal testing with the soil covered, the growth of both the monocot and dicot plants was completely prevented after 5 to 7 days of SA fumigation, resulting in the deaths of entire plants. It was noteworthy that in the post-emergent herbicidal testing, SA dissolved in ethanol (60%, v/v) completely disrupted the growth of the monocot and dicot plants as early as 3 days after SA emission from the nutshells, even without the soil being covered. Tree-nutshell particles could serve as effective SA delivery vehicles with controlled release capabilities for SA. The SA exhibited pre- and post-emergent herbicidal activities against the monocot and dicot plants at most growth stages. SA (0.8 and 1.6 M) dissolved in ethanol (60%, v/v) might exert a synergism for higher herbicidal activity after emission from nutshells. Since tree nuts capture/store a substantial amount of carbon over their life-cycles, the new and sustainable utility of using nutshells not only reduces carbon emissions but also valorizes tree-nut by-products, thus benefitting the tree-nut industry. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to investigate the anti-erosion potential of taproots and fibrous roots with different diameters in alluvial loess under the concentrated flow. Materials and methods: A pot experiment was conducted in the greenhouse. Alluvial loess widely distributed in north China was used for plant growing. Two herbs, alfalfa (Medicago sativa) with taproots and tall festuca (Festuca arundinacea) with fibrous roots, were selected for single and mixed planting. Root configuration and soil detachment capacity (Dc) at different depths were measured, then the anti-erosion potential of taproots and fibrous roots with different diameters was analyzed. Results and discussion: Fibrous roots exhibited greater root length density (RLD) and fine root (0–1 mm) ratio at all depths, while taproots had larger mean diameter and root volume density (RVD). The Dc was reduced by 25.3–56.6% in the presence of roots compared to soil without roots, and the Dc of single fibrous roots treatment was significantly lower than that of single taproots and mixed roots. Whether in soil containing taproots or fibrous roots, Dc was only significantly negatively correlated with the density of very fine roots (< 0.5 mm). In fibrous roots, the direct path coefficient of very fine roots to Dc was significantly higher than that of roots at other diameter classes, while in taproots, the direct path coefficient of coarse roots (> 2 mm) to Dc was highest. Conclusions: Variations in root diameter (< 0.5, 0.5–1, 1–2, > 2 mm) distribution and root density are important factors contributing to differences in Dc at different depths. In alluvial loess with low clay and high silt content, the high density of very fine roots (< 0.5 mm) in fibrous roots is critical for demonstrating greater anti-erosion potential. The presence of more medium roots (1–2 mm) and coarse roots (> 2 mm) is the main reason for decreasing in the anti-erosion potential of taproots. [ABSTRACT FROM AUTHOR]

Riparian plant species can differ in their responses to streamflow variation in ways that strongly influence the composition and functioning of riparian plant communities. Quantifying these differences and the potential asymmetry of responses to low- versus high-flow phases of stream fluctuations is important for predicting and managing vegetation responses to variation in flow regimes. We measured the physiological response of two riparian plant species with different habitat preferences to an experimental flow that progressed from a low-flow to high-flow phase. Schedonorous arundinaceus, a hydric grass growing in near-channel habitat, exhibited significant and biologically substantial declines in stem water potential (SWP) during the low-flow phase of the experiment and a saturating increase in leaf relative water content (LRWC) during the high-flow phase. These patterns are consistent with cavitation risk in response to low-flow anomalies and saturating responses to high-flow anomalies in this hydric species. Pluchea sericea, a mesic shrub growing at intermediate elevations above the channel, exhibited a decrease in LRWC during the low-flow phase and an increase in SWP during the high-flow phase. These patterns are consistent with protection from stem cavitation risk during drought through leaf dehydration and opportunistic increases in water status in response to high-flow anomalies in this mesic species. The asymmetrical responses of both species to low- versus high-flow phases demonstrate unique physiological responses to flow anomalies of contrasting directions attributable to species habitat preferences and functional strategies that can be used by managers to predict non-linear vegetation responses to flow variation. [ABSTRACT FROM AUTHOR]

Complex environmental conditions like heavy metal contamination and elevated CO2 concentration may cause numerous plant stresses and lead to considerable crop losses worldwide. Cadmium is a non-essential element and potentially highly toxic soil metal pollution, causing oxidative stress in plants and human toxicity. In order to assess a combination of complex factors on the responses of two genotypes of Festuca arundinacea (75B and 75C), a greenhouse experiment was conducted on plants grown in two Cd-contaminated soil conditions and two soil textures under combined effects of elevated ambient CO2 (700 ppm) and Epichloë endophyte infection. Plant biomass, Cd, Fe, Cu, Zn, and Mn concentrations in the plant shoots and roots, Fv/Fm, chlorophyll (a & b), and carotenoid contents were measured after 7 months of growth in pots. Our results showed that endophyte-infected plants (E+) grown in elevated CO2 atmosphere (CO2+), clay-loam soil texture (H) with no Cd amendment (Cd−) in the genotype 75B had significantly greater shoot and root biomass than non-infected plants (E−) grown in ambient CO2 concentration (CO2−), sandy-loam soil texture (L) with amended Cd (Cd+) in the genotype 75C. Increased CO2 concentration and endophyte infection, especially in the genotype 75B, enabled Festuca for greater phytoremediation of Cd because of higher tolerance to Cd stress and higher biomass accumulation in the plant genotype. However, CO2 enrichment negatively influenced the plant mineral absorption due to the inhibitory effects of high Cd concentration in shoots and roots. It is concluded that Cd phytoremediation can be positively affected by the increased atmospheric CO2 concentration, tolerant plant genotype, heavy soil texture, and Epichloë endophyte. Using Taguchi and AIC design methodologies, it was also predicted that the most critical factors affecting Cd phytoremediation potential were CO2 concentration and plant genotype. [ABSTRACT FROM AUTHOR]

Water treated with low-pressure glow plasma of low frequency takes unique properties which might be utilized as a novel, beneficial nitrogen fertilizer. That assumption is tested in this report. Thus, plantations of dill (Anethum graveolens) var. Moravan, grass Universal (5% westerwold ryegrass (Lolium multiflorum), 20% tall fescue (Festuca arundinacea), 40% perennial ryegrass (Lolium perenne), 35% red festuce (Festuca rubra) and strawberry ((Fragaria) var. Senga Sengana were watered with that nitrogen fertilizer (LPGPAm) prepared of 1% ammonia solution in tap water treated for 30 min with plasma generated at 38 oC at 5x10-3 mbar, 800 V, 50 mA and 10 kHz frequency. Watering lasted from August 1th (sowing) till September 30th (harvesting) 2023 in a greenhouse. The effect of the use of watering plants with LPGPAm was checked involving the following parameters: plant height, mass of stems, total mass of crops, content of fat, proteins, carotenoids, ascorbic acid, sulphur content chlorophyll, content of dry mass, and ash and bioaccumulation of cations and anions. [ABSTRACT FROM AUTHOR]

Rising incidences of waterlogging and salinity, particularly in extensive livestock farming areas, pose increasing challenges to plant growth. This study investigated the morphological growth responses and tolerance of 39 Festuca arundinacea accessions to these stresses, with tolerance quantified by the relative growth rate under stress versus control conditions. Notably, more productive accessions under normal conditions also showed greater stress tolerance. Waterlogging was generally welltolerated (89-113% of control relative growth rate), without significantly altering growth morphological components as increases in specific leaf area were offset by reductions in leaf weight ratio, maintaining stable leaf area ratios. Conversely, salinity and combined saline waterlogging significantly reduced relative growth rate (56-94% of control), with a substantial variation among accessions. Adecrease inspecific leaf area, suggestive of thicker leaves, correlated with higher tolerance to salinity and saline waterlogging (r = 0.63). In summary, F. arundinacea displays diverse tolerance to these stresses, warranting further study into the adaptive mechanisms. Specific leaf area emerges as a potential selection marker for breeding programs targeting saline and waterlogging tolerance. [ABSTRACT FROM AUTHOR]

Introduction: Festuca species are forage grasses that are very important in terms of fodder supply and soil protection. The seeds of these plants have internal dormancy (physiological) and are unable to germinate easily. Therefore, they must be subjected to various treatments to germinate. In nature, this dormancy is broken during the cold period of winter (chilling). The purpose of this research is to investigate different methods of dormancy breaking in Festuca species for large-scale production and accelerate the germination process. Materials and methods: In this research, three species of Festuca (Festuca arundinacea, F. ovina, and F. rubra) were subjected to different treatments of chilling (4°C, 14 days), osmo-priming with potassium nitrate (KNO3) 1.5% and gibberellic acid 150 and 200 ppm. After 14 days of germination test, various germination indices including percentage and rate of germination, mean germination time, seed vigor index, length of radicle, shoot and seedling, and the ratio of radicle to shoot length were calculated. Results: The results of the analysis of variance showed a significant difference between species (except for germination percentage and root length traits) and treatments (for all traits). The interactions between the species and treatment were also significant for all traits (except for the length of radicle and seedling). Among the three species, the percentage of germination varied from 26.67 to 30.67% and the value of the germination rate varied from 1.92 to 3.31 n/d. The average time required for germination varied from 3.75 to 4.36 days and the seed vigor index varied from 26.74 to 43.02. The radicle length was between 37.22 and 45 mm and the shoot length was between 37.34 and 81.33 mm. Based on principal components analysis (PCA), percentage and rate of germination, seed vigor index, and length of radicle and seedling were introduced as the most important factors in creating diversity in Festuca species. In determining the correlation between traits, a high correlation of 70% was observed between germination percentage, germination rate, and seed vigor index. Conclusion: Among the three species, Festuca rubra was superior to the other two species by having the highest percentage and rate of germination, seed vigor, radical length, and the shortest time required for germination. Among the applied treatments, 1.5% potassium nitrate (KNO3) with chilling (4°C, for 14 days), had a positive effect on the percentage and rate of germination, radical length, and gibberellic acid (150 ppm) treatment had a positive effect on the length of shoot and seedling. The presence of high germination percentage and rate indicated higher seed vigor. [ABSTRACT FROM AUTHOR]

Abstract—The association of degradation of membrane-bound chlorophyll with changes in the dark respiration rates and photosynthesis in Festuca arundinacea Schreb. leaves under the influence of various concentrations of limited and aromatic hydrocarbons present in technogenic emissions was studied. One day after intoxication, a negative correlation between the content of non-phytol forms of pigments and the rate of photosynthesis was found. A positive correlation was found between the content of (1) phytol forms and the rate of photosynthesis and (2) non-phytol forms and the respiration rate. The relationships between the processes changed three days after characterizing the detoxifying and adaptive abilities of plants. [ABSTRACT FROM AUTHOR]

Natural soil inundation caused by frequent and intense precipitation affects carbon allocation in grassland biomass, ultimately leading to changes in soil carbon storage. Increasing forage diversity could provide resiliency to inundation of grassland. The objective was to evaluate forage and root biomass and C and N stocks in the soil particulate organic matter (POM) from pastures under recurring short‐term inundation. Three forage species combinations were evaluated in an inundated (typically lasting for a few days after heavy rain events) and a non‐inundated pasture: (1) predominantly tall‐fescue (Festuca arundinacea Schreb.); (2) mixture of cool‐season perennials composed of tall‐fescue, orchardgrass (Dactylis glomerata L.), bluegrass (Poa pratensis L.) and white (Trifolium repens L.) and red clover (Trifolium pratense L.); (3) and cool‐season mixture of perennials overseeded with oats (Avena strigosa Schreb.) and rye (Secale cereale L.). Roots and forage biomass were sampled during the growing seasons of 2021 and 2022. Soil POM was evaluated 2.5 years after establishment. Inundation reduced forage and root biomass mainly during periods of higher inundation frequency, leading to lower C‐POM stocks (p <.05). Inundation caused a shift in the forage botanical composition, that is, higher occurrence of weeds and less productive grass species with shallow roots. The perennial cool‐season mixture did not increase forage yield compared with tall fescue only but did increase root mass. This occurred mainly at deeper layers and, consequently, increased C‐POM stocks (p <.05). Overseeding of winter annuals reduced overall forage production, despite increasing spring biomass when inundated in the first year, but reduced C and N‐POM stocks (p <.05). Perennial cool‐season forage mixtures can increase the resilience of pastures to inundation events and contribute to increased carbon sequestration in grasslands where inundation is prevalent. [ABSTRACT FROM AUTHOR]

Fructans in cool‐season grasses may have some negative effects on equine health. However, they may have positive effects on ruminant performance, and fructans of different lengths appear to be metabolized differently in the rumen. Hence, seasonal variation in fructan concentrations may impact equine and ruminant performance. Long‐chain fructan with degree of polymerization (DP) > 8, short‐chain fructan (DP 4 to 8), raffinose, and three fructan trisaccharides were profiled and quantified in timothy (Phleum pratense L.) cultivar 'Clair' and tall fescue (Festuca arundinacea Schreb.) cultivar 'Cajun II' harvested in April, June, August, and October of two consecutive years in central Kentucky. Harvest year influenced concentrations of long‐chain fructan (p =.0017). Harvest date influenced species differences in raffinose (p =.0035), which was most abundant in timothy in June, and in 1‐kestose and neokestose (p <.0001), which were most abundant in tall fescue in April. Harvest date influenced species differences in short‐ and long‐chain fructan (p <.0001). Tall fescue had two‐ to three‐fold more short‐chain fructan than timothy in April, August, and October. Timothy had two‐ to five‐fold more long‐chain fructan than tall fescue in April, June, and October. Species choice and weather patterns may have contributed to relatively low concentrations of all the carbohydrates measured in this study. Fermentation or feeding studies could help to determine if the concentrations present could affect equine health or ruminant performance. [ABSTRACT FROM AUTHOR]