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• Different configurations were tested for producing biogas from roadside grass. • Dry digestion succeeded at pilot and large scale, but the latter can be improved. • Digested fibers performed better than undigested fibers for biomaterial production. • Anaerobic digestion might be stopped midway for improved fiber recovery. • Market potential of roadside grass for biomaterials production was significant. Roadside grass clippings hold potential as a sustainable source of bioenergy as they do not compete with crops for land use, and are only partially utilized for low-value applications. In this study, we proposed using roadside grass as a sole feedstock for anaerobic digestion (AD) in three different settings, and assessed the potential of producing biomaterials and fertilizers from grass-based digestate. Wet continuous digestion at pilot scale and dry batch digestion at pilot and large scales resulted in biogas yields up to 700 Nm3.t−1 DOM with a methane content of 49–55 %. Despite promising results, wet AD had operational problems such as clogging and poor mixing; once upscaled, the dry digestion initially also presented an operational problem with acidification, which was overcome by the second trial. Digested grass fibers from the pilot dry AD were processed into biomaterials and performed similarly or better than the undigested fibers, while around 20 % performance reduction was observed when compared to reference wood fibers. A mass balance indicated reduced fiber recovery when higher biogas production was obtained. The liquid fraction from the pilot dry AD was characterized for its nutrient content and used as a biofertilizer in another study. In contrast, the leachate collected from the large-scale dry AD had a low nitrogen content and high chloride content that could hinder its further use. Finally, a regional market analysis was conducted showing that the biocomposites produced with the available grass fibers could substitute at least half of the current European market based on our results. [ABSTRACT FROM AUTHOR]

We analysed the effects of black geotextile inter-row mulch, grass mulch and clean tillage as a control on the microclimate, anthocyanin components and fruit quality of 'Xinyu' table grape in a semi-arid climate. Black geotextile inter-row mulch increased the air and soil temperatures, while grass mulch decreased these. Six types of anthocyanins were detected in the grapes. Around 50% of the total anthocyanins were malvidin based (38.60%–39.10%) and peonidin based (25.80%–31.10%), with malvidin-3-O-glucoside being the main pigment (38.75%–39.05%), followed by peonidin-3-O-glucoside (23.84%–28.68%). The soluble solid content, reducing sugar content and sugar-acid ratio for the black geotextile treatment group were 12.93%, 10.05% and 25.85% higher, respectively, than the control. By contrast, grapes in the grass mulch treatment group had a significantly lower soluble solid content than the control, with a 7.32% reduction being observed. Neither type of mulch had a large effect on the vitamin C content nor yield. However, both black geotextile inter-row mulch and grass mulch could regulate the orchard microclimate and increased the total anthocyanin content by 36.04% and 5.03%, respectively, compared with the control. These findings suggest that grass mulch is the preferable cultivation method in the Turpan area. [ABSTRACT FROM AUTHOR]

Summary: The oxygen isotope composition of cellulose (δ18O values) has been suggested to contain information on stomatal conductance (gs) responses to rising pCO2. The extent by which pCO2 affects leaf water and cellulose δ18O values (δ18OLW and δ18OC) and the isotope processes that determine pCO2 effects on δ18OLW and δ18OC are, however, unknown.We tested the effects of pCO2 on gs, δ18OLW and δ18OC in a glasshouse experiment, where six plant species were grown under pCO2 ranging from 200 to 500 ppm.Increasing pCO2 caused a decline in gs and an increase in δ18OLW, as expected. Importantly, the effects of pCO2 on gs and δ18OLW were small and pCO2 effects on δ18OLW were not directly transferred to δ18OC but were attenuated in grasses and amplified in dicotyledonous herbs and legumes. This is likely because of functional group‐specific pCO2 effects on the model parameter pxpex.Our study highlights important uncertainties when using δ18OC as a proxy for gs. Specifically, pCO2‐triggered gs effects on δ18OLW and δ18OC are possibly too small to be detected in natural settings and a pCO2 effect on pxpex may render the commonly assumed negative linkage between δ18OC and gs to be incorrect, potentially confounding δ18OC based gs reconstructions. [ABSTRACT FROM AUTHOR]

Agrivoltaic systems combine solar energy and agriculture, promoting dual land use. Although grazing sheep in these systems is common, research on intentionally designed pastures to increase production is lacking. This study seeks to compare the herbage growth and lamb production in simple, diverse, and legume pastures in an agrivoltaic system over 2 years in Oregon. Annual herbage production in diverse pastures (4583 kg DM ha−1) was comparable to simple pastures (4457 kg DM ha−1), but higher than legume pastures (p <.05; 4023 kg DM ha−1) for the 2020/2021 growing season. In the 2021/2022 growing season, diverse pastures had a higher yield (4660 kg DM ha−1, p <.05) than simple pastures (4052 kg DM ha−1), which were similar to legume pastures (3955 kg DM ha−1). Liveweight gain (LWG; g head−1 d−1) tended (p =.06) to be higher from lambs in diverse and legume pastures compared to simple pastures in spring 2021. Liveweight production (LWP; kg ha−1 d−1) of legume pasture were greater (P < 0.05) than other pasture types, while simple pastures had the lowest LWP during this period. In summer 2021, LWG tended to be greater in lambs grazing diverse versus simple pastures. No difference was detected (all p >.05) in LWG or LWP at any grazing period in 2022. Overall, efficiency of pasture production was greatly reduced by lower light availability in all pasture types. Diversification of pastures using forbs in agrivoltaics was a good strategy for greater herbage production, while the legume pastures had poor persistence. [ABSTRACT FROM AUTHOR]

The geographical distribution of bermudagrass cultivars is limited by freezing events (<0°C), commonly associated with higher latitudes in the northern hemisphere. The lipid composition in the plant cell membranes is critical to promote persistence under freezing conditions. This study evaluated herbage accumulation (HA), nutritive value, and lipid biosynthesis of different bermudagrass cultivars in Ona, FL (27°26' N 82°55' W) and Marianna, FL (30o52' N 85o11' W), in 2 years. Treatments were five bermudagrass cultivars (Coastal, Tifton 44, Tifton 85, Jiggs, and Mislevy) distributed in a randomized complete block design with four replicates. HA was greater in Marianna than in Ona for all cultivars (p < 0.05). Mislevy and Jiggs had greater HA in Marianna than the others (p < 0.05), while all cultivars were similar in Ona (p > 0.05). There was no difference between locations or among the cultivars for crude protein and neutral detergent fibre, but bermudagrass cultivars had greater in vitro digestibility of organic matter (IVDOM) in Marianna than in Ona (p < 0.05). The concentration of unsaturated fatty acids increased in the northern latitude (Marianna; p < 0.05). Coastal had greater unsaturated fatty acid concentration than other cultivars (p < 0.05). Geographical location affects HA, IVDOM, and unsaturated fatty acid concentration of bermudagrass cultivars. The unsaturated fatty acid concentration plays a key role in acclimating bermudagrass to different thermal environments. Coastal showed great potential to tolerate chilling stress in Florida. Further studies may be developed to identify promising molecular markers for cold tolerance in bermudagrass. [ABSTRACT FROM AUTHOR]

Leys are an important part of northern European livestock production, particularly for ruminants since monogastric animals are limited in their ability to digest the fibres of the forage. Crop fractionation methods are a promising option to make forages more beneficial for monogastric animals and decrease the amount of imported protein feed. A leaf stripping harvesting technique was evaluated at Röbäcksdalen in northern Sweden in mixed grass‐clover leys over 2 years. The PremAlfa Mini leaf stripper (Trust'ing‐Alf'ing, Nantes, France) worked well in mixed stands, harvesting on average a third of the available forage biomass, primarily in the form of leaves and soft stems from the clover plants. It proved successful in producing a forage fraction that had a significantly higher crude protein (CP) concentration (+39.1%) and lower neutral detergent fibre (aNDFom) concentration (−21.4%) than the pre‐harvest mixed sward (all significant at p <.05 level). Due to the remaining high level of aNDFom in the leaf stripper fraction, it is more suited for use as an energy source for monogastrics rather than as a protein supplement. Alternatively, the leaf stripper fraction could be used to increase digestibility and CP content in the feed rations of high producing dairy cows. [ABSTRACT FROM AUTHOR]

This article is a book review of two works about the German Nobel laureate Günter Grass. The first book, "Günter Grass: Der Schriftsteller" by Dieter Stolz, is a comprehensive introduction to Grass's poetry, dramas, and prose fiction. The reviewer notes that Stolz's personal connection to Grass influences his perspective, but praises his deep knowledge of Grass's works. The second book, "Katalogisierung und Kommentierung der Jugendlektüren von Günter Grass in den 1930er und frühen 1940er Jahren" by Dorothee Neuhaus and Volker Neuhaus, focuses on Grass's early life and the books that influenced his literary output. The reviewer highlights the book's insightful interpretations and its value for researchers. [Extracted from the article]

The repeated emergence of NADP–malic enzyme (ME), NAD–ME and phosphoenolpyruvate carboxykinase (PEPCK) subtypes of C4 photosynthesis are iconic examples of convergent evolution, which suggests that these biochemistries do not randomly assemble, but are instead specific adaptations resulting from unknown evolutionary drivers. Theoretical studies that are based on the classic biochemical understanding have repeatedly proposed light‐use efficiency as a possible benefit of the PEPCK subtype. However, quantum yield measurements do not support this idea. We explore this inconsistency here via an analytical model that features explicit descriptions across a seamless gradient between C4 biochemistries to analyse light harvesting and dark photosynthetic metabolism. Our simulations show that the NADP–ME subtype, operated by the most productive crops, is the most efficient. The NAD–ME subtype has lower efficiency, but has greater light harvesting plasticity (the capacity to assimilate CO2 in the broadest combination of light intensity and spectral qualities). In both NADP–ME and NAD–ME backgrounds, increasing PEPCK activity corresponds to greater light harvesting plasticity but likely imposed a reduction in photosynthetic efficiency. We draw the first mechanistic links between light harvesting and C4 subtypes, providing the theoretical basis for future investigation. Summary statement: NAD‐malic enzyme (ME) and phosphoenolpyruvate carboxykinase C4 subtypes have greater light harvesting plasticity but lower efficiency than the NADP–ME subtype. [ABSTRACT FROM AUTHOR]

Perennial tall grasses show promise as bioenergy crops due to high productivity and efficient nutrient use. Ongoing research on bioenergy grasses seeks to reduce their reliance on synthetic nitrogen (N) fertilizer, the manufacture of which relies on fossil fuel combustion. Excessive use of fertilizers also causes adverse environmental consequences and leads to the evolutionary loss of plant traits beneficial to sustainable N cycle. Notably, perennial tall grasses have exhibited the potential to maintain high biomass yield without the need for N fertilizer or causing soil N depletion. Perennial grasses can be adept at interacting with their microbial partners to facilitate N acquisition and retention via mechanisms such as biological N fixation and nitrification inhibition. These inherent N management traits should be preserved and optimized at the this early stage of bioenergy grass breeding programs. This review examines the impact of external N on bioenergy grass production and explores the potential of leveraging advantageous N‐cycling attributes of perennial tall grasses, laying groundwork for future management and research efforts. With minimized dependency on external N input, the cultivation of perennial energy grasses will pave the way toward more resilient agricultural systems and play a significant role in addressing key global energy and environmental challenges. [ABSTRACT FROM AUTHOR]

Hemicellulose extracted by alkali treatment is of interest because of the advantages of its intact sugar structure and high degree of polymerization. However, the hemicellulose extracted by alkali treatment contained more lignin fragments and the presence of a lignin–carbohydrate complex (LCC), which affected the isolation and purification of hemicellulose and its comprehensive utilization. Therefore, the evaluation of the LCC structure of different types of lignocellulosic resources is of great significance. In this study, the LCC structures of hardwoods and Gramineae were enriched in alkaline systems. Information on the composition, structural proportions, and connection patterns of LCC samples was discussed. The similarities and differences between the LCC structures of different units of raw materials were comparatively studied. The results indicated that the monosaccharide fractions were higher in the LCC of Gramineae compared to hardwoods. The composition of the lignin fraction was dominated by G and S units. The phenyl glycosidic (PhGlc) bond is the predominant LCC linkage under alkali-stabilized conditions. In addition, Gramineae PhGlc types are more numerous compared to hardwoods. The results of the study provide insights into the differences in the chemical composition and structural features of LCC in different plants and provide important guidance for the optimization of the process of purifying hemicellulose. [ABSTRACT FROM AUTHOR]

The introduction of improved forage varieties could play a crucial role in meeting the growing demand for livestock and livestock products in Ethiopia. However, different cultivars exhibit varied performance. Therefore, this study aimed to assess the performance of Brachiaria cultivars and other grass cultivars in two subhumid agroecological areas of Ethiopia. Four Brachiaria cultivars (B. brizantha (DZF-13379), B. humidicola (DZF-9222), B. decumbens (DZF-10871), and B. mutica (var. DZF-483), and two local grass cultivars, Rhodes grass (Chloris gayana var. Massaba) and Desho grass (Pennisetum glaucifolium var. Kindu Kosha), were evaluated in Bako and Bishoftu for three years during the rainy season. The experiment was carried out using a completely randomized block design. Results indicated that both cultivars and years had significant (P < 0.001) effects on herbage dry matter (DM) yield, crude protein (CP) yield, and plant height, whereas location only affected DM yield. Significant cultivar × year interactions were observed for DM yield, CP yield, and plant height, while cultivar × location interactions had a significant effect on all parameters except for CP yield. Additionally, cultivars significantly (P < 0.001) impacted the in vitro dry matter digestibility (IVDMD) as well as the nutritional content (CP, ash, acid detergent lignin (ADL), neutral detergent fiber (NDF), and acid detergent fiber (ADF). Overall, all cultivars demonstrated potential as alternative ruminant feeds, with B. mutica, followed by B. brizantha, showing superior performance in the subhumid agroecological areas of Ethiopia. [ABSTRACT FROM AUTHOR]

Background: Woody bamboos are the only diverse large perennial grasses in mesic-wet forests and are widely distributed in the understory and canopy. The functional trait variations and trade-offs in this taxon remain unclear due to woody bamboo syndromes (represented by lignified culm of composed internodes and nodes). Here, we examined the effects of heritable legacy and occurrence site climates on functional trait variations in leaf and culm across 77 woody bamboo species in a common garden. We explored the trade-offs among leaf functional traits, the connection between leaf nitrogen (N), phosphorus (P) concentrations and functional niche traits, and the correlation of functional traits between leaves and culms. Results: The Bayesian mixed models reveal that the combined effects of heritable legacy (phylogenetic distances and other evolutionary processes) and occurrence site climates accounted for 55.10–90.89% of the total variation among species for each studied trait. The standardized major axis analysis identified trade-offs among leaf functional traits in woody bamboo consistent with the global leaf economics spectrum; however, compared to non-bamboo species, the woody bamboo exhibited lower leaf mass per area but higher N, P concentrations and assimilation, dark respiration rates. The canonical correlation analysis demonstrated a positive correlation (ρ = 0.57, P-value < 0.001) between leaf N, P concentrations and morphophysiology traits. The phylogenetic principal components and trait network analyses indicated that leaf and culm traits were clustered separately, with leaf assimilation and respiration rates associated with culm ground diameter. Conclusion: Our study confirms the applicability of the leaf economics spectrum and the biogeochemical niche in woody bamboo taxa, improves the understanding of woody bamboo leaf and culm functional trait variations and trade-offs, and broadens the taxonomic units considered in plant functional trait studies, which contributes to our comprehensive understanding of terrestrial forest ecosystems. [ABSTRACT FROM AUTHOR]

Background and aims: Surface protection of coalmine overburden (OB) dumps against shallow slope failures can be achieved through a cost-effective and sustainable solution, i.e., vegetative cover. Hence, a small-scale study is needed to study the survival, growth performance, and root distribution of plants prior to conducting a pilot-scale study. Methods: In the present study, three plant species, Dendrocalamus strictus (Bamboo grass), Cymbopogon citratus (Lemon grass), and Chrysopogon zizanioides (Vetiver grass), an endemic grass species, are studied for the slope stabilization potential of OB dumps in Jharkhand, India. Growth characteristics and root architecture of grasses grown for five months under six varying proportions (treatments) of overburden, cow dung, and garden soil were studied. Results: It was found that Vetiver grass had the highest root area ratio, followed by Bamboo grass and Lemon grass. The maximum root cohesion was found to be 1 kPa for Bamboo grass, 7.33 kPa for Lemon grass, and 9.24 kPa for Vetiver grass among different treatments. Conclusions: Treatment condition with 80% overburden and 20% cow dung was suggested to be the best soil mix for optimum growth of the chosen grasses, which have the potential to mitigate surficial movement of soil mass on the overburden dumps through root reinforcement. [ABSTRACT FROM AUTHOR]

The imagery of Nebuchadnezzar's divine affliction in Daniel 4 is as complex as it is fantastic. A variety of literary images interweave to present the king's affliction in explicitly animalising terms. Despite this complexity, most visual depictions of the text focus on a largely similar image – that of Nebuchadnezzar eating grass or living naked in the wild. However, in a 17th-century English tapestry series associated with Thomas Poyntz, an altogether different scene is envisioned. Nebuchadnezzar is portrayed as fully clothed in the city of Babylon and, even more intriguingly, is explicitly depicted with both birds' claws and feathers. This paper outlines trends in visually depicting Nebuchadnezzar's affliction in art and then examines the tapestry's visual portrayal of Daniel 4. In so doing, it is observed how the tapestry is distinctive in representing both the divine pronouncement and seeming enactment of this affliction in one image, as well as discerning the influence of lycanthropic interpretations of Daniel 4. Finally, this paper returns to read the biblical narrative in light of this unusual visual representation and observes how it draws the reader's attention to two often overlooked textual features: the absence of other characters within this specific scene, and the rapidity with which Nebuchadnezzar's affliction commences. [ABSTRACT FROM AUTHOR]

This research work was conducted to investigate the anatomical and antioxidant studies of some ethnoveterinary grasses (Cenchrus pennisetiformis and Dichanthium annulatum). The anatomical characteristics (compact epidermal layer, large cortical cells, thickened sclerenchyma, central and scattered vascular bundles, large metaxylem, small protoxylem, and centrally located pith) were observed. For the antioxidant activity studies, the crude methanol extract was prepared by maceration techniques and different fractions were prepared (n-hexane, chloroform, and aqueous solution). The maximum antioxidant potential in DPPH was shown by C. pennisetiformis at a concentration of 250 μL in the chloroform fraction, while D. annulatum showed a maximum value of 68.47±0.30 at a concentration of 250 μL in the methanolic extract. In both species, chloroform extract in TAA showed maximum potency at a concentration of 500 μL, but C. pennisetiformis showed a higher value (i.e. 1.15±0.0018) and D. annulatum showed a lever value (i.e. 1.05±0.0017). The best reducing power in FRAP was shown by D. annulatum followed by C. pennisetiformis. C. pennisetiformis showed the highest value in the chloroform fraction while D. annulatum showed a higher significant value in the methanol fraction. These grasses have the potential to control several diseases caused by ROS in animals. [ABSTRACT FROM AUTHOR]

Ethnoveterinary medicine is crucial in many rural areas of Pakistan, as residents in remote and marginal areas rely heavily on traditional herbal medicines to cure their domestic animals. Reactive oxygen species (ROS) formed spontaneously as by products of reactions with O2 molecules, chemically damage the organic elements of the cell such as nucleic acids, proteins, and lipids. In the current research work, the anatomical, phytochemical and antioxidant of some ethnoveterinary grasses were studied. A total of four species were collected from different villages of Hafizabad during the months of April and May 2021. The collected species were identified as Cenchrus setigerus Vahl, Diplachne fusca (L.) P. Beauv., Imperata cylinderica (L.) Raeuschel and Sporobolus coromandelianus Kunth. For the anatomical studies, stems and leaves were cut into thin sections with a microtome. The anatomical characteristics observed were a compact epidermal layer, large cortical cells, thickened sclerenchyma, central and scattered vascular bundles, a large metaxylem, a small protoxylem, a pitted phloem, and a centrally located pith. To investigate the phytochemical and antioxidant potential, the crude methanol extract was prepared by maceration and subjected to fractionation with n-hexane, petroleum ether, chloroform, methanol, and water. D. fusca showed strong scavenging activity i.e. 75.87±0.14 of DPPH at 250 µL concentration. The total antioxidant activity evaluated by phosphomolybdenum activity showed the best results in the methanol fraction of D. fusca. At a concentration of 125 µL, the methanol extracts showed maximum reducing potential of 1.20±0.06. The methanol extracts of all grasses showed maximum ferric-reducing antioxidant potential except I. cylinderica, which showed a maximum potential of 1.77±0.054 TE µM/mL in chloroform extracts. The methanol extract of I. cylinderica had the highest TPC value of 118.32±1.27 (GAE) mg/mL. This study provides experimental confirmation that grasses, when consumed, can be used as natural antioxidants and can be used to combat various diseases caused by reactive oxygen species. [ABSTRACT FROM AUTHOR]

Context: Seasonal variations between the rain and dry seasons are the main obstacle to agricultural productivity in tropical regions, making it essential to conserve surplus for periods of scarcity. One of the limiting factors in ensiling grasses is moisture, requiring the use of additives or withering. Using a mixture of grasses and legumes can be an alternative to balance the advantages and disadvantages of both in the ensiling process, and mata-pasto hay (MPH) can be an option. Aims: This study evaluated different forms of Tanzania grass (Megathyrsus maximum) and MPH silages, as well as silages with increasing levels of MPH. Methods: Silages of Tanzania grass and MPH in their natural form, as well as silages with increasing doses of MPH, were evaluated for nutritional value, degradability in situ. The microbiology was also evaluated. Key results: Among the types of silages, natural MPH and wilted MPH were superior to natural Tanzania grass silage. The use of MPH in Tanzania grass silages improves fermentation processes, the population of beneficial microorganisms, resulting in better nutritional value of these silages. Conclusions: Natural and wilted MPH hay silages are qualitatively better compared to natural Tanzania grass silage. Increasing doses of MPH improve the quality of the silage. A recommended dose is 30% of MPH hay. Implications: Adding MPH to silages is a way to reduce the negative impacts of this weed on pastures. However, further studies with the use of complementary additives are needed. The seasonality between the rainy and dry seasons is a challenge for tropical agriculture. This study evaluated different forms of ensiling Tanzania grass (Megathyrsus maximum) and forest pasture hay (FPH) aiming to improve the conservation and nutritional value of silages. Results showed that the use of 30% FPH improved the fermentative processes and the nutritional value of the silages. This strategy can reduce the negative impacts of weeds on pastures, although further research is needed for complementary additives. [ABSTRACT FROM AUTHOR]

Synchronizing the timing of reproduction with the environment is crucial in the wild. Among the multiple mechanisms, annual plants evolved to sense their environment, the requirement of cold-mediated vernalization is a major process that prevents individuals from flowering during winter. In many annual plants including crops, both a long and short vernalization requirement can be observed within species, resulting in so-called early-(spring) and late-(winter) flowering genotypes. Here, using the grass model Brachypodium distachyon , we explored the link between flowering-time-related traits (vernalization requirement and flowering time), environmental variation, and diversity at flowering-time genes by combining measurements under greenhouse and outdoor conditions. These experiments confirmed that B. distachyon natural accessions display large differences regarding vernalization requirements and ultimately flowering time. We underline significant, albeit quantitative effects of current environmental conditions on flowering-time-related traits. While disentangling the confounding effects of population structure on flowering-time-related traits remains challenging, population genomics analyses indicate that well-characterized flowering-time genes may contribute significantly to flowering-time variation and display signs of polygenic selection. Flowering-time genes, however, do not colocalize with genome-wide association peaks obtained with outdoor measurements, suggesting that additional genetic factors contribute to flowering-time variation in the wild. Altogether, our study fosters our understanding of the polygenic architecture of flowering time in a natural grass system and opens new avenues of research to investigate the gene-by-environment interaction at play for this trait. [ABSTRACT FROM AUTHOR]

Background and Aims The grass genus Urochloa (Brachiaria) sensu lato includes forage crops that are important for beef and dairy industries in tropical and sub-tropical Africa, South America and Oceania/Australia. Economically important species include U. brizantha , U. decumbens , U. humidicola , U. mutica , U. arrecta , U. trichopus , U. mosambicensis and Megathyrsus maximus , all native to the African continent. Perennial growth habits, large, fast growing palatable leaves, intra- and interspecific morphological variability, apomictic reproductive systems and frequent polyploidy are widely shared within the genus. The combination of these traits probably favoured the selection for forage domestication and weediness, but trait emergence across Urochloa cannot be modelled, as a robust phylogenetic assessment of the genus has not been conducted. We aim to produce a phylogeny for Urochloa that includes all important forage species, and identify their closest wild relatives (crop wild relatives). Finally, we will use our phylogeny and available trait data to infer the ancestral states of important forage traits across Urochloa s.l. and model the evolution of forage syndromes across the genus. Methods Using a target enrichment sequencing approach (Angiosperm 353), we inferred a species-level phylogeny for Urochloa s.l. , encompassing 54 species (~40 % of the genus) and outgroups. Phylogenies were inferred using a multispecies coalescent model and maximum likelihood method. We determined the phylogenetic placement of agriculturally important species and identified their closest wild relatives, or crop wild relatives, based on well-supported monophyly. Further, we mapped key traits associated with Urochloa forage crops to the species tree and estimated ancestral states for forage traits along branch lengths for continuous traits and at ancestral nodes in discrete traits. Key Results Agricultural species belong to five independent clades, including U. brizantha and U. decumbens lying in a previously defined species complex. Crop wild relatives were identified for these clades supporting previous sub-generic groupings in Urochloa based on morphology. Using ancestral trait estimation models, we find that five morphological traits that correlate with forage potential (perennial growth habits, culm height, leaf size, a winged rachis and large seeds) independently evolved in forage clades. Conclusions Urochloa s.l. is a highly diverse genus that contains numerous species with agricultural potential, including crop wild relatives that are currently underexploited. All forage species and their crop wild relatives naturally occur on the African continent and their conservation across their native distributions is essential. Genomic and phenotypic diversity in forage clade species and their wild relatives need to be better assessed both to develop conservation strategies and to exploit the diversity in the genus for improved sustainability in Urochloa cultivar production. [ABSTRACT FROM AUTHOR]

On grassland and savanna restoration sites, planted native C4 grasses can competitively exclude other co‐introduced plant functional groups, with negative implications for ecosystem functioning and restoration success. Previous studies have suggested that C4 grass competitive exclusion does not occur in longleaf pine savannas of the North American Coastal Plain; however these studies were primarily conducted on old growth xeric sites. We designed an experiment to test competitive interactions between C4 grasses and forbs introduced by seed to mesic savanna restoration sites. Research installations were established on three former bahiagrass (Paspalum notatum) pastures in Florida, within which six different seed treatments were applied: (1) C4 grasses and forbs together in years 1 and 2, (2) C4 grasses alone in year 1 and forbs alone in year 2, (3) forbs alone in year 1 and C4 grasses alone in year 2, (4) C4 grasses alone in both years, (5) forbs alone in both years, and (6) an unplanted control. All plots were sampled 1 year after the second seeding event. We found that C4 grasses competitively excluded forbs, reducing cover of forbs arriving on the site at the same time, as well as those arriving in the second year. The highest forb species richness and cover was found in the three treatments that did not contain C4 grasses in year 1, and different C4 grass species exhibited different community associations. These findings suggest that restoration seed mixes for longleaf pine savannas should account for the competitive interactions of C4 grasses. [ABSTRACT FROM AUTHOR]

Plant essential macronutrients like nitrogen (N) and phosphorus (P) can limit savanna tree growth and are important determinants of savanna vegetation dynamics, along with rainfall, fire and herbivory. How nitrogen and phosphorus shape tree‐grass competition and their coexistence remain unclear, hindering our ability to predict how savannas may respond to altered nutrient cycling.Here, we evaluate (1) if trees and grasses respond differently to N versus P availability, or (2) if grasses are more competitive in low nutrient environments while trees are more competitive in high nutrient environments. To do this, we grew saplings of 6 tree and 1 grass species from the Kruger National Park, South Africa, for 16 weeks under fully factorial nutrient and competition treatments (with/without competitors, low/high rate of N supply and low/high rate of P supply) under a watering regime designed to mimic wet season rainfall in a mesic savanna.Trees and grasses foraged most aggressively for nitrogen and allocated biomass differently depending on nitrogen availability. Overall, tree growth decreased in competition with grass, even in high nutrient environments where they grew faster. Grasses were always better below‐ground competitors, utilising aggressive nutrient foraging strategies, including high root phosphatase activity in response to nitrogen and large root biomass allocation.Synthesis. In low nutrient environments (e.g. on nutrient‐poor sandy soils), nutrients may limit tree growth. Nutrient rich environments enable tree growth, but grasses continue to compete effectively with trees. Understanding what this means for ecosystem responses to nutrient availability is not trivial, especially in the context of fire and herbivory. However, it is clear that soil nutrients likely affect tree and grass growth and competition in savannas, which suggests that future changes in nutrient cycling, such as N deposition, may have important effects on savanna vegetation. [ABSTRACT FROM AUTHOR]

This article presents the results of an ongoing inventory of Ascomycota in Yunnan, China, carried out as part of the research project series "Exploring ascomycete diversity in Yunnan". From over 100 samples collected from diverse host substrates, microfungi have been isolated, identified and are currently being documented. The primary objective of this research is to promote the discovery of novel taxa and explore the ascomycete diversity in the region, utilising a morphology-phylogeny approach. This article represents the second series of species descriptions for the project and introduces three undocumented species found in the families Bambusicolaceae, Dictyosporiaceae and Periconiaceae, belonging to the suborder Massarineae (Pleosporales, Dothideomycetes). These novel taxa exhibit typical morphological characteristics of Bambusicola, Periconia and Trichobotrys, leading to their designation as Bambusicola hongheensis, Periconia kunmingensis and Trichobotrys sinensis. Comprehensive multigene phylogenetic analyses were conducted to validate the novelty of these species. The results revealed well-defined clades that are clearly distinct from other related species, providing robust support for their placement within their respective families. Notably, this study unveils the phylogenetic affinity of Trichobotrys within Dictyosporiaceae for the first time. Additionally, the synanamorphism for the genus Trichobotrys is also reported for the first time. Detailed descriptions, illustrations and updated phylogenies of the novel species are provided, and thus presenting a valuable resource for researchers and mycologists interested in the diversity of ascomycetes in Yunnan. By enhancing our understanding of the Ascomycota diversity in this region, this research contributes to the broader field of fungal taxonomy and their phylogenetic understanding. [ABSTRACT FROM AUTHOR]

The genus Clavibacter (family Microbacteriaceae) includes gram‐positive actinobacterial species infecting diverse agricultural crops such as alfalfa, maize, pepper, potato, tomato and wheat. Clavibacter tessellarius, causing bacterial mosaic of wheat, was reported for the first time in 1976 in Nebraska (United States). Since then, the pathogen was thought to be restricted to North America (Canada and the United States). While bacterial strains suspected to be C. tessellarius have occasionally been isolated from wheat samples outside North America, occurrence of the pathogen in the Old World has not yet been confirmed by the plant protection authorities. In spring 2020 (January to May) dozens of wheat fields with young plants showing leaf chlorosis and mild mosaic symptoms were surveyed and sampled in southern Iran. Among 192 surveyed wheat fields, gram‐positive, orange‐pigmented actinobacterial strains were isolated from samples of 53 fields. Altogether, 61 bacterial strains were identified as C. tessellarius based on the phenotypic features, PCR‐based molecular tests and pathogenicity assays. Multilocus sequence analysis of five housekeeping genes (atpD, dnaK, gyrB, ppk and rpoB) using 10 representative strains from diverse geographic areas in southern Iran confirmed the phylogenetic status of the strains within C. tessellarius. Our data indicate that the bacterial mosaic pathogen occurs in four southern Iranian provinces including Bushehr, Fars, Kerman and Khuzestan. Thus, occurrence of C. tessellarius outside North America is confirmed. Potential risks associated with the emergence of the pathogen in the Old World, and the need for strict quarantine measures in the area, is further discussed. [ABSTRACT FROM AUTHOR]

• Elymus scabrifolius reproduces sexually and its embryo sacs are of Polygonum type. • This species has a mixed and mainly autogamous reproductive system. • Self-pollination occurs between the florets of the same inflorescence, or between the inflorescences of the same plant by geitonogamy. • All the evaluated populations have high fertility rate. Elymus scabrifolius is a perennial forage species valued as a plant genetic resource for degraded areas and for crop improvement, being a source of salt-tolerant related genes. In this study, we determined the breeding system of this species by analyzing seed set under different pollination treatments, phenology, floral traits, and embryological development in four Argentine populations. The results indicate that E. scabrifolius has a mixed, sexual, and mainly autogamous reproductive system. Plants from all populations produced high seed percentages, with significant differences among them. Self-pollination occurred fundamentally between the chasmogamous florets of the same plant by geitonogamy. This mode of selfing results from the flowering synchrony and the architecture of inflorescences. Self-pollination by cleistogamy had low rates and was observed in only two populations. This information may be useful to estimate the potential utility of this species as a phytogenetic resource, and to design efficient collection and conservation programs. [ABSTRACT FROM AUTHOR]

Non‐native annual grasses have invaded western rangelands in the United States, and novel approaches are needed to supplement existing management strategies. The aim of this study was to investigate biofumigation, the use of Brassicaceae products to suppress weeds, as a control for two non‐native annual grasses (cheatgrass, Bromus tectorum and ventenata, Ventenata dubia) and its effects on two dominant native perennial grasses (bluebunch wheatgrass, Pseudoroegneria spicata and Idaho fescue, Festuca idahoensis). We tested the effect of the biofumigant Brassica juncea (brown mustard), applied as seed meal and mulch, on germination metrics of the four grass species in Petri dishes. Germination metrics included emergence and viability, time to cotyledon and radicle emergence and their lengths at 14 days after sowing. Impacts on emergence and viability were assessed using a binomial mixed effects model, while time to cotyledon and radicle emergence and lengths were assessed using linear mixed effects models. Seed meal reduced emergence and viability at lower application rates for V. dubia and F. idahoensis than the other two species. Mulch did not consistently reduce emergence or viability. P. spicata was the least inhibited by the biofumigants. When using seed meal, radicle emergence and length were inhibited in B. tectorum, V. dubia and F. idahoensis and cotyledon emergence and length were inhibited for all. The mulch did not impact these metrics consistently and may not be a viable management tool. The use of seed meal biofumigant to suppress undesired annual grasses in rangelands seems promising, but response is species‐specific. [ABSTRACT FROM AUTHOR]

Due to increased consumption, artificial sweeteners are often present in the environment but their effects on plants are largly unknown. In this research, the effects of four artificial sweeteners on plant stress markers in Triticum aestivum L. were investigated. Wheat seedlings were grown from seeds in soil containing artificial sweeteners (saccharin, sodium cyclamate, sucralose, aspartame) in different concentrations (0, 25, 50, 100 mg kg-1). Plants were irrigated at regular intervals to maintain field capacity moisture and harvested after 15 days of growth. Electrolyte leakage, chlorophyll and carotenoid content, and antioxidant enzyme (superoxide dismutase, peroxidase, catalase) activities were determined in harvested leaves. Comparisons between control samples and test samples were statistically evaluated at a 95% confidence interval to determine significant differences. Overall, significant increases in chlorophyll and carotenoid content, and some antioxidant enzyme activities were observed in wheat plants exposed to artificial sweeteners in the soil. A significant increase in electrolyte leakage was observed with saccharin and aspartame treatment, indicating that these sweeteners can cause membrane damage in wheat. Chlorophyll a and POX activity were the most sensitive stress parameters in wheat. This study showed the importance of evaluating the potential impact of anthropogenic pollutants that may be present in treated wastewater and consequently affect plants. [ABSTRACT FROM AUTHOR]

Rising platemeters are commonly used in Ireland and New Zealand for managing intensive pastures. To assess the applicability of a commercial rising platemeter operating with a microsonic sensor to estimate herbage mass with its own equation, the objectives were (i) to validate the original equation; (ii) to identify possible factors hampering its accuracy and precision; and (iii) to develop a new equation for heterogeneous swards. A comprehensive dataset (n = 1511) was compiled on the pastures of dairy farms. Compressed sward heights were measured by the rising platemeter. Herbage mass was harvested to determine reference herbage availability. The adequacy of estimating herbage mass was assessed using root mean squared error (RMSE) and mean bias. As the adequacy of the original equation was low, a new equation was developed using multiple regression models. The mean bias and the RMSE for the new equation were overall low with 201 kg dry matter/ha and 34.6%, but it tended to overestimate herbage availability at herbage mass < 500 kg dry matter/ha and underestimate it at >2500 kg dry matter/ha. Still, the newly developed equation for the microsonic sensor-based rising platemeter allows for accurate and precise estimation of available herbage mass on pastures. [ABSTRACT FROM AUTHOR]

Whole-plant hydraulics provide important information about responses to water limitation and can be used to understand how plant communities may change in a drier climate when measured on multiple species. Here, we measured above- and belowground hydraulic traits in Cornus drummondii, an encroaching shrub within North American tallgrass prairies, and Andropogon gerardii, a dominant C4 grass, to assess the potential hydraulic responses to future drought as this region undergoes woody expansion. Shelters that reduced precipitation by 50% and 0% were built over shrubs and grasses growing in sites that are burned at 1-year and 4-year frequencies. We then measured aboveground (Kshoot), belowground (Kroot), and whole-plant maximum hydraulic conductance (Kplant) in C. drummondii and Kroot in A. gerardii. We also measured vulnerability to embolism (P50) in C. drummondii stems. Overall, we show that: (1) A. gerardii had substantially greater Kroot than C. drummondii; (2) belowground hydraulic functioning was linked with aboveground processes; (3) above- and belowground C. drummondii hydraulics were not negatively impacted by the rainfall reductions imposed here. These results suggest that a multi-year drought will not ameliorate rates of woody expansion and highlight key differences in aboveground and belowground hydraulics for dominant species within the same ecosystem. [ABSTRACT FROM AUTHOR]

The use of chemical inputs has led to the loss of microbial diversity involved in the N cycle, such as diazotrophic bacteria, which are inhibited by saturation of the receptors responsible for activating nitrogenase. Biological nitrogen fixation (BNF) in forage grasses can be used as an ecosystem service. The aim of this review was to analyze the contribution of forage grasses to BNF and their response to inoculation of non-symbiotic diazotrophs in order to find study opportunities. The analysis of the information was carried out using the prisma methodology of systematic reviews and meta-analyses. It should be noted that the main forage species that contribute to BNF are Brachiaria sp. and Pennisetum sp. The inoculation of Azospirillum sp. has generated a growth-promoting effect in grasses, but the response of the inoculated forage depends mainly on the synergy between plant and bacteria, showing neutral, antagonistic, and positive effects. [ABSTRACT FROM AUTHOR]

AP2/ERF transcription factor family plays an important role in plant development and stress responses. Previous studies have shed light on the evolutionary trajectory of the AP2 and DREB subfamilies. However, knowledge about the evolutionary history of the ERF subfamily in angiosperms still remains limited. In this study, we performed a comprehensive analysis of the ERF subfamily from 107 representative angiosperm species by combining phylogenomic and synteny network approaches. We observed that the expansion of the ERF subfamily was driven not only by whole-genome duplication (WGD) but also by tandem duplication (TD) and transposition duplication events. We also found multiple transposition events in Poaceae, Brassicaceae, Poales, Brassicales, and Commelinids. These events may have had notable impacts on copy number variation and subsequent functional divergence of the ERF subfamily. Moreover, we observed a number of ancient tandem duplications occurred in the ERF subfamily across angiosperms, e.g., in Subgroup IX, IXb originated from ancient tandem duplication events within IXa. These findings together provide novel insights into the evolution of this important transcription factor family. [ABSTRACT FROM AUTHOR]

In simulation-based training, learners apply skills in an environment that approximates the real conditions of work. Trainers who design a simulation also employ assumptions about the design of communication, or how they believe learners should communicate. More specifically, simulation-based training events draw work groups' attention to communication expectations related to timing, timelines, and timeliness. Competing perspectives may produce temporality tensions. To better understand how temporality tensions affect work and workers, I conducted a qualitative case study of a large, multi-agency disaster-response exercise (the 'Tall Grass' exercise), which simulated a search-and-rescue operation. I identified competing design logics related to synching work streams, pacing activities, and providing feedback or input at the 'right' time, and I identified counterproductive effects of adopted communication designs. In response to the findings, I suggest alternative designs for communication that offer better function, fit, and attention to fragmented interests. [ABSTRACT FROM AUTHOR]

The increasing cost of fossil-based energy sources has driven research in bio-based alternatives, such as perennial grasses for feedstock. The mid-Atlantic receives appreciable summer rainfall that may support a two-cut-per-year−1 harvest. At Virginia State University, a study on annual forage sorghum and two one-year stand perennials, miscanthus, and selected switchgrass ecotypes was carried out. The experimental design was a split-plot with harvest systems and feedstock grass species randomly assigned to the main and sub-plots, respectively. Only perennial grasses were assigned to the two-cut-per-year−1 system. The first cut occurred in early summer, and the second and single cut occurred after the frost-kill. Under the two-cut system, in 2022, the first-cut dry matter (DM) yield ranged from 8.9 Mg ha−1 in Blackwell to 14.7 Mg ha−1 in BoMaster. Additionally, except for BoMaster, the regrowth DM yields were within 10% of the first-cut DM yield. Under the one-cut system, the yield ranged from 10.8 Mg ha−1 in Blackwell to 23.2 Mg ha−1 in sorghum. Under the two-cut system, in 2023, miscanthus produced the greatest first-cut DM yield of 18.4 Mg ha−1, while other perennials averaged 10.1 Mg ha−1. Compared to the first cut, the hot and dry summer significantly reduced regrowth for all feedstock species, with the miscanthus DM yield dropping by 64%. While forage attributes differ among feedstock species, in general, both the first cut and regrowth showed greater crude protein and mineral elements, as well as lower ADF contents compared to a single cut following a killing freeze. Sorghum had better forage quality for the one-cut-per-year−1 feedstock material, and, along with the first cut and regrowth, it may have the potential for use as forage for maintenance energy in animal systems. For perennials, the two-cut-per-year−1 system removed the greatest quantities of nutrients during both years, with the first-cut harvest contributing about 65% of all removed N and K. Sorghum removed the greatest quantities of nutrients compared to the perennial under a one-cut-per-year−1 system. Therefore, while a two-cut-per-year−1 system can result in the greatest DM yields for dual-purpose use, its adoption calls for a critical analysis of economic benefits that considers feedstock bioenergy processing approaches, stand persistence, and fertilizer management strategies to address potential soil fertility depletion due to mineral element mining. [ABSTRACT FROM AUTHOR]

In tropical regions, grass silage can be produced from the pasture in the rainy season to feed animals during the dry season. We evaluated the chemical composition and fermentation characteristics of ensiled signal grass (Urochloa decumbens Stapf. Basilisk) fertilized with nitrogen (N) or intercropped with calopo (Calopogonium mucunoides Desv.) with and without microbial inoculant. We used a 4 × 2 factorial scheme in a randomized block design, with two blocks and two treatments per block, considering p > 0.05. We studied signal grass fertilized with 0 kg ha−1 of N (0 N), 50 kg ha−1 of N (50 N), or 100 kg ha−1 of N (100 N), or intercropped with calopo legume (LEG), with (I) or without (WI) inoculant, in two seasons. During the dry–water transition, lower concentrations of butyric acid were observed in 50 N and LEG silages (2.77 and 2.55 g kg−1 dry matter, DM) (inoculated) compared to control (7.77 g kg−1 DM). During the water–dry transition, higher concentrations of crude protein were observed in 100 N and LEG silages (71.90 and 54.6 g kg−1 DM) than in 0 N (46.3 g kg−1 DM). The signal grass–calopo intercropping is an alternative to nitrogen fertilization, as it provides forage with a higher protein content and silage with satisfactory fermentative characteristics. [ABSTRACT FROM AUTHOR]

The concentration of linoleic and a-linolenic fatty acids (FA) in grasses can be increased through agronomic techniques; however, there is little information in this regard for tropical grasses. Therefore, the objective of the study was to evaluate the effect of N fertilization and regrowth age management on the FA profile of three tropical grasses. To do this, three plots of 100 m2 each were used for the species: Urochloa decumbens (Stapf) R.D. Webster, U. humidicola (Rendle) Morrone & Zuloaga, and Megathyrsus maximus (Jacq.) B.K. Simon & S.W.L. Jacobs. The study was conducted during dry and rainy seasons. In each period, they were divided into two subplots and only one of them was fertilized. Grass sampling was carried out on days 20, 25, and 30 after fertilization. Five samples were taken from each subplot and an agronomic evaluation was made before each cut. The chemical composition and lipid profile were then determined. An ANOVA of a randomized complete block design with split plot arrangement was performed. The concentration of linoleic and a-linolenic acid was higher in M. maximus during drought (48.5 g 100 g-1 FA) and in U. humidicola during the rainy season (55.1 g 100 g-1 FA). This proportion was higher on day 20 (50.5 g 100 g-1 FA) compared to that recorded on days 25 and 30 (50.1 and 45.7 g 100 g-1 FA, respectively). The fertilized grasses had a higher concentration of linoleic and a-linolenic acid compared to the unfertilized ones (53.4 vs. 44.3 g 100 g-1 FA). It is concluded that fertilization with 50-20-00 (N-P-K) increases the proportion of linoleic and a-linolenic acids in grasses; however, such concentration decreases with increasing plant maturity. [ABSTRACT FROM AUTHOR]

The interaction between pasture and supplementation in dairy production systems constitutes a very important part of the efficiency of dairy. This study evaluated the effect of the herbage mass (HM) on the milk production and solid concentration. Twenty Holstein cows were distributed into two groups, 10 assigned 2200 kg DM ha-1 (low herbage mass, LHM) and 10 with 2800 kg DM ha-1 (medium herbage mass, MHM). Herbage mass was measured above 5 cm. The experiment lasted 8 wk. The variables evaluated were DM intake (DMI), milk production and composition (fat and protein concentration). Effects of treatments on variables were evaluated using a repeated measure analysis over time. The results showed nonsignificant differences in the pasture DMI between LHM and MHM for weeks 1, 2, 3 and 5 (P > 0.05). During week 4, pasture DMI was 3 kg greater for LHM than MHM (P < 0.05). The milk production did not differ between treatments per week, but the average was 2.4 kg greater for LHM compared to MHM (P < 0.05). In conclusion, changes in the pasture availability increased milk production at LHM, but not enough to cause changes in solids concentration. This clearly shows that, LHM can increase milk and solids production. [ABSTRACT FROM AUTHOR]

Larvae of Melolonthinae (white grubs) are usually considered as serious pests for some of them attacking plant roots and causing great losses of agriculture and forestry. However, not all the white grubs are pest species. In this study, the adult Apogonia cupreoviridis were observed to feed on gramineous grasses and fallen ginkgo leaves, while their larvae were frequently collected in the lawn. The larvae were reared in the laboratory and observed using scanning electron microscopy. The larvae have the plegmatia expanded in the middle; distal antennomere with an apical process bearing one bifurcated sensilla and nine sensilla basiconica on the apex; the palidia are V‐shaped and each palidium bearing five to nine pali. The V‐shaped palidia are found in the known larvae of Diplotaxini, as to genera Apogonia and Liogenys. [ABSTRACT FROM AUTHOR]

Shrub encroachment is one of the primary threats to mesic grasslands around the world. This dramatic shift in plant cover has the potential to alter ecosystem‐scale water budgets and responses to novel rainfall regimes. Understanding divergent water‐use strategies among encroaching shrubs and the grasses they replace is critical for predicting shifts in ecosystem‐scale water dynamics as a result of shrub encroachment, particularly if drought events become more frequent and/or severe in the future.In this study, we assessed how water‐use traits of a rapidly encroaching clonal shrub (Cornus drummondii) and a dominant C4 grass (Andropogon gerardii) impact responses to changes in water availability in tallgrass prairie. We assessed intra‐annual change in depth of water uptake, turgor loss point and stomatal regulation in each species. Sampling took place at Konza Prairie Biological Station (northeastern KS, USA) during the 2021 and 2022 growing seasons.Cornus drummondii shifted from shallow to deep soil water sources across the 2021 and 2022 growing seasons. This plasticity in depth of water uptake facilitated a 'wasteful' water‐use strategy in C. drummondii, where stomatal conductance and transpiration rates continued to increase even when no further gain in photosynthetic rate occurred. A. gerardii photosynthetic rates and stomatal conductance were more variable through time and were more responsive to changes in leaf water potential than C. drummondii. However, intra‐annual adjustment of turgor loss point was more pronounced in C. drummondii (ΔπTLP = −0.48 MPa ± 0.15 SD) than in A. gerardii (ΔπTLP = −0.29 MPa ± 0.19 SD).Synthesis. These results suggest that C. drummondii is highly resilient to changes in water availability in surface soils and will likely remain unaffected by future droughts unless they are severe enough to reduce the availability of deep soil water. Given that clonal shrubs are key invaders of grasslands world‐wide, increased leaf‐level water loss is expected to accelerate ecosystem‐level drying as clonal shrub encroachment proceeds in mesic grasslands. [ABSTRACT FROM AUTHOR]

Invasive clonal species may exhibit different growth strategies than their native clonal competitors. In this study, we examined the spatial distribution of tiller outgrowth and the bud bank by comparing the investment in phalanx versus guerilla growth of a native and invasive perennial grass in North America. We also examined the effect of altered precipitation frequency, clipping, and competition on their clonal growth strategies. Investment in phalanx and guerilla growth was assessed by examining live propagule and tiller production from the plant crown versus its rhizomes. Although invasive Bromus inermis and native Pascopyrum smithii exhibited similar clonal growth strategies as young seedlings, their clonal growth strategies significantly differed by the end of their first growing season. Pascopyrum smithii invested in dual phalanx and guerilla tiller outgrowth and bud placement, and B. inermis primarily invested in phalanx tiller outgrowth and bud placement. Competition rather than intra-annual precipitation variability and clipping altered the clonal growth strategy of these species. Intra- and inter- specific competition did not alter tiller outgrowth for either species. However, inter-specific competition caused both species to alter their bud placement. Bromus inermis shifted more buds from phalanx to guerilla positions while P. smithii shifted in the opposite direction. This may enable invasive B. inermis to expand while confining native P. smithii to more localized areas in the future. Clonal growth strategies appear to be species specific and responsive to inter-specific competition. Investigating the belowground bud aspect of clonal growth can reveal the mechanism driving the future aboveground clonal growth strategy of native and invasive rhizomatous grasses and help inform the patterns of invasion within a plant community. [ABSTRACT FROM AUTHOR]

A four-dimensional mathematical model is formulated to explore the fear effect exerted by large carnivore in the grassland ecosystem. The model depicts the interactions among herbage, domestic herbivore, wild herbivore and large carnivore, which incorporates both direct predation and anti-predator mechanisms. The dynamic properties of the model are analytically investigated, including the dissipativity of solutions, and the existence and stability of different equilibria. Some numerical simulations are also presented to exhibit rich dynamical behaviors, such as various types of bistabilities, periodic oscillation and chaotic oscillation. The study reveals that the appropriate level of fear factors can stabilize the system and increase the density of herbage and domestic herbivore. The fear effect plays an important role in maintaining the balance of the grassland ecosystem and promoting the economy of human society. [ABSTRACT FROM AUTHOR]

The present study assessed the influence of the preceding crop (crotalaria or corn) on the bromatological, digestibility and microbiological aspects of the EMBRAPA 139 black oat hay (Avena strigosa) cultivar. A randomized block design was used, with subplots divided according to time, whereby the preceding crop (crotalaria or corn) was allocated to the main plot and hay storage times (baling, 30, 60 and 90 days of storage) to the subplots, with five repetitions. Crotalaria as predecessor resulted in lower indigestible fiber and higher protein contents in black oat hay, both in acid detergent, as well as higher pH. Corn as the preceding crop provided better hay digestibility due to lower neutral detergent insoluble protein content and higher in vitro neutral detergent fiber digestibility. The preceding crop did not significantly affect the drying time of forage and the microorganism population. [ABSTRACT FROM AUTHOR]

Environmental niche modeling (ENM) has emerged as a promising tool for identifying grass species with potential for rangeland restoration. This approach can detect suitable areas and environments where these species can be planted. In this study, we employed ENM to estimate the potential distribution range of 50 grass species of the grasslands and shrublands of northern Mexico. The outcome of the ENM served to identify grass species with potential for restoration in Mexico, especially those not commonly used for that purpose in the past. Results suggested the possibility of selecting seven grass species with the potential for revegetating degraded grasslands, nine for shrublands, and six for alkaline soils. This research provides insights into the environmental adaptations of different grass species distributed in the rangelands of northern Mexico. Ecologists, conservation planners, researchers, and range managers could use these outcomes and the maps of the potential distribution ranges as supportive information to conduct effective restoration efforts. In turn, this can assist in increasing the probability of success of future rangelands restoration programs, which are often costly in terms of financial investments and labor. [ABSTRACT FROM AUTHOR]

Summary: Increasing rainfall variability is widely expected under future climate change scenarios. How will savanna trees and grasses be affected by growing season dry spells and altered seasonality and how tightly coupled are tree–grass phenologies with rainfall?We measured tree and grass responses to growing season dry spells and dry season rainfall. We also tested whether the phenologies of 17 deciduous woody species and the Soil Adjusted Vegetation Index of grasses were related to rainfall between 2019 and 2023.Tree and grass growth was significantly reduced during growing season dry spells. Tree growth was strongly related to growing season soil water potentials and limited to the wet season. Grasses can rapidly recover after growing season dry spells and grass evapotranspiration was significantly related to soil water potentials in both the wet and dry seasons. Tree leaf flushing commenced before the rainfall onset date with little subsequent leaf flushing. Grasses grew when moisture became available regardless of season.Our findings suggest that increased dry spell length and frequency in the growing season may slow down tree growth in some savannas, which together with longer growing seasons may allow grasses an advantage over C3 plants that are advantaged by rising CO2 levels. [ABSTRACT FROM AUTHOR]

This study compared animal performance and enteric methane (CH4) emissions from dairy cows in a part-time grazing (PTG) system in northern Sweden. Twenty-four Nordic Red dairy cows were allocated to one of two treatments: DAY (10 h daytime pasture access) or NIGHT (12 h night-time pasture access). The cows in each treatment received the same ad libitum partial mixed ration (PMR) indoors and ad libitum herbage allowance. Methane was recorded using two linked GreenFeedTM emissions monitoring (GEM) units, on pasture and indoors. Day or night grazing showed no statistical differences in estimated grass or PMR intake, milk production or daily enteric CH4 emissions. There was a rapid decrease in diurnal CH4 emissions (28%) when the cows were moved from indoors to pasture in both grazing treatments. Using two GEM units (indoor, outdoor) in combination improved the diurnal assessment of enteric CH4 emissions during PTG conditions in the mixed feeding system. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the nutritive value of Panicum maximum and Brachiaria brizantha cultivars in terms of nutrient composition, dry matter intake, and digestibility at different harvesting stages. The factors investigated were three cultivars; Mombaca, Gutton (Panicum maximum), and Marandu (Brachiaria brizantha), and three harvesting intervals (6, 10, and 14 weeks) after planting (WAP). Collected grass samples were subjected to nutrient and in-vitro dry matter digestibility analysis. The cultivars and harvesting stages influenced (P < 0.05) the nutrient composition, dry matter intake (DMI), invitro dryy matter digestibility (IVDMD), relative feed value (RFV), and total digestible nutrients (TDN) of grasses. There was an interaction between the cultivars and harvesting intervals on acid detergent lignin (ADL), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), K/Ca + Mg, copper (Cu), iron (Fe), zinc (Zn), and manganese (Mn). It can be concluded that Panicum maximum and Brachiaria brizantha cultivars can support optimum ruminant livestock production, and, the nutritive value of the Marandu cultivar supersedes minimum animal requirements. [ABSTRACT FROM AUTHOR]

Empirical invasion ecology is laden with high context dependency. If general mechanisms underlying invasion success exist, they should be detectable in species that share biological and ecological characteristics. We carried out a growth experiment with Agropyron cristatum, Bromus inermis and Poa pratensis (subsp. angustifolia), to better understand the mechanisms underlying the invasion success of cool‐season grasses in northern prairie grasslands of North America. By using a home–away approach, we tested whether 1) non‐native plants have a higher performance than native plants, and whether invasiveness is 2) mediated by interactions with soils, such as a release from pathogens or enhanced mutualism, or 3) an adaptation to local soils. We compared seed size and weight of populations in Canada (non‐native range) and Eurasia (native range) and carried out an experiment, in which seeds from the non‐native and native ranges were planted into sterilized soil (control) and soil from a population in Canada or Eurasia, or local soils, respectively. We found inconsistent effects across species and response variables. Seed size and weight were not significantly different between native and non‐native populations. The experiment showed a seed origin effect in A. cristatum (root and total biomass) and B. inermis (root biomass), with non‐native populations outperforming native ones. Soil‐mediated effects were supported in A. cristatum (root biomass) and local adaptation in B. inermis (root and total biomass). Germination across all species and biomass in P. pratensis did not respond to treatments. Despite the high similarity of our study group, our results indicate that invasiveness might be driven by idiosyncratic causes at the species level. Mechanisms not considered in our study, such as high propagule pressure and preadaptation could also potentially explain the invasion success across species. [ABSTRACT FROM AUTHOR]

Nickel (Ni) is extremely toxic to plants at high concentrations. Phytoliths have the potential to sequester the heavy metals absorbed by plants and act as a detoxification mechanism for the plant. The authors of the present study aimed to evaluate the effects of Ni on the growth and phytolith yield of grasses in two artificially contaminated soils. Two experiments separated by soil types (Typic Quartzipsamment and Rhodic Hapludox) were conducted in a completely randomized design in a 2 × 4 factorial scheme with three replications. The factors were two species of grass (Urochloa decumbens and Megathyrsus maximus) and three concentrations of Ni (20, 40, and 120 mg kg−1) and control treatment. The grasses were influenced by the increase in Ni rates in the soils. Ni exerted a micronutrient function with the addition of 30 mg kg−1 of Ni in soils, but this concentration caused toxicity in grasses. Such a level is lower than the limits imposed by the Brazilian environmental legislation. Higher Ni availability in Typic Quartzipsamment promoted Ni toxicity, with reduced growth and increased phytolith yield in the shoot, increased Ni in the shoot, and Ni occlusion in phytoliths by grasses, in comparison with Rhodic Hapludox. The yield and Ni capture in phytoliths by grasses in Ni-contaminated soils are related to the genetic and physiological differences between grasses and Ni availability in soils. Ni capture by phytoliths indicates that it may be one of the detoxification mechanisms of Urochloa decumbens to Ni contamination, providing additional tolerance. Megathyrsus maximus may be a future grass for the phytoremediation technique in Ni-contaminated soils. [ABSTRACT FROM AUTHOR]