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AbstractIn February 2021, elongated grey lesions with reddish margin were observed on sudangrass (Sorghum × drummondii) leaves, in the municipality of Guasave, Sinaloa, Mexico. These symptoms resembled those of leaf blight caused by Bipolaris and Exserohilum on other grasses. Two fungal isolates were recovered from symptomatic leaves, and their identities were confirmed based on a polyphasic approach. The morphological and phylogenetic analysis of the actin gene (act) and internal transcribed spacer region (ITS) of both isolates revealed their identity as Exserohilum turcicum. A pathogenicity test with a representative isolate confirmed this fungus as the causal agent of leaf blight on sudangrass, as symptoms previously observed in the field were developed on the inoculated plants. The E. turcicum isolate was recovered from the diseased sudangrass plants, fulfilling Koch’s postulates. This is the first report of E. turcicum causing leaf blight on sudangrass in Mexico. [ABSTRACT FROM AUTHOR]

Background: Desertification is the most severe environmental problem in arid and semi-arid regions and has caused great economic loss every year. However, artificial sand fixation barriers function on sand fixation for only 10–20 years. Searching for a native species with long-term sand fixation effect and strong environmental adaptive capacity, and low water consumption is needed. In this study, we investigated the environmental adaption and sand fixation effect of a grass from Poaceae family (Psammochloa villosa) that is indigenous to the desert of Northwest China. Results: The results showed that P. villosa has a streamlined leaf form, strong mechanical strength, and flexibility to adapt to wind. Leaf curling of P. villosa under drought decreased water loss rate through decreased evaporation area to adapt to drought. Significant negative relationship between adventitious root length and horizontal root burial depth indicates that adventitious roots help P. villosa absorb water and nutrients from soil under shallow sand burial condition, which enables P. villosa to adapt to different sand burial conditions. P. villosa fixed sand dunes through the distribution of the population at the top of the dune and the vertical relationship between the direction of windblown sand and the direction of growth of P. villosa, which stopped the expansion of the dune. Conclusions: Growth characteristics of wind and drought tolerant leaf traits and adventitious roots under sand burial indicate that P. villosa is well adapted to dry sandy desert conditions and burial by sand. The distribution of the P. villosa population on the sand dune is a "brake" on its expansion. These findings provide new insight for active sand dune fixation and desertification control using native grass in the desertified regions. [ABSTRACT FROM AUTHOR]

The woody bamboos (Bambusoideae) exhibit distinctive biological traits within Poaceae, such as highly lignified culms, rapid shoot growth, monocarpic mass flowering and nutlike or fleshy caryopses. Much of the remarkable morphological diversity across the subfamily exists within a single hexaploid clade, the paleotropical woody bamboos (PWB), making it ideal to investigate the factors underlying morphological evolution in woody bamboos. However, the origin and biogeographical history of PWB remain elusive, as does the effect of environmental factors on the evolution of their morphological characters. We generated a robust and time‐calibrated phylogeny of PWB using single nucleotide polymorphisms retrieved from optimized double digest restriction site associated DNA sequencing, and explored the evolutionary trends of habit, inflorescence, and caryopsis type in relation to environmental factors including climate, soil, and topography. We inferred that the PWB started to diversify across the Oligocene–Miocene boundary and formed four major clades, that is, Melocanninae, Racemobambosinae s.l. (comprising Dinochloinae, Greslanlinae, Racemobambosinae s.str. and Temburongiinae), Hickeliinae and Bambusinae s.l. (comprising Bambusinae s.str. plus Holttumochloinae). The ancestor of PWB was reconstructed as having erect habit, indeterminate inflorescence and basic caryopsis. The characters including climbing/scrambling habit, determinate inflorescence, and nucoid/bacoid caryopsis have since undergone multiple changes and reversals during the diversification of PWB. The evolution of all three traits was correlated with, and hence likely influenced by, aspects of climate, topography, and soil, with climate factors most strongly correlated with morphological traits, and soil factors least so. However, topography had more influence than climate or soil on the evolution of erect habit, whereas both factors had greater effect on the evolution of bacoid caryopsis than did soil. Our results provide novel insights into morphological diversity and adaptive evolution in bamboos for future ecological and evolutionary research. [ABSTRACT FROM AUTHOR]

Grass endophytic fungi have garnered increasing attention as a prolific source of bioactive metabolites with potential application across various fields, including pharmaceticals agriculture and industry. This review paper aims to synthesize knowledge on the diversity, isolation, and bioactivity of metabolites produced by grass endophytic fungi. Additionally, this approach aids in the conservation of rare and endangered plant species. Advanced analytical techniques such as high-performance liquid chromatography, liquid chromatograpy-mass spectrometry and gas chromatography are discussed as critical tools for metabolite identification and characterization. The review also highlights significant bioactive metabolites discovered to date, emphasizing their antimicrobial, antioxidant, and insecticidal activities and plant growth regulation properties. Besides address the challenges and future prospects in harnessing grass endophytic fungi for sustainable biotenological applications. By consolidating recent advancements and identifying agaps in the current research, this paper provides a comprehensive overview of the potential grass endophytic fungi as a valuable resource for novel bioactive compounds. [ABSTRACT FROM AUTHOR]

The Festuca marginata group includes several taxa of glaucous, thick-leaved fescues with three sclerenchyma strands, first described by Hackel as Festuca ovina subsp. laevis, which are common in the Euro-Mediterranean area. Ten different taxa (species and subspecies) are currently recognized in this group. Nevertheless, taxonomical works typically have only a local (mostly national) scope, and the recognized taxa show only few or negligible morphological differences, making their separate taxonomic status doubtful. Here we provide morphological, karyological, and genetic analysis (ISSR, flow cytometry) of the Festuca marginata group based on populations in a larger geographical scale including Central and Southern-Eastern Europe. We found that most of the local taxa are difficult to definitively distinguish and we suggest the whole group be treated as a single species, Festuca marginata, with two subspecies reflecting major differences in morphology and genome size between the Greece subsp. heldreichii and the remaining European populations, referred to as subsp. marginata. [ABSTRACT FROM AUTHOR]

Ctenium has about 20 species distributed in Africa, Arabia, and the Neotropics, with no species occurring on more than one continent. Its relationship with the morphologically similar Kampochloa is still unclear and has not been investigated. In this study, we performed phylogenomic analyses using 71 protein‐coding genes of 24 newly sequenced plastomes, of 13 species of Ctenium and 1 species of Kampochloa to understand their biogeography and the phylogenetic and evolutionary relationships between these two genera and within Ctenium. Our results support two major clades of Ctenium: the Neotropics and Old‐World clades. Kampochloa is shown to be a close relative of the genus Ctenium, and their morphological similarities support this. Divergence time estimation analyses show that Kampochloa and Ctenium diverged around 7.99 Ma, and might have originated in the late Miocene during the rapid expansion of C4 grasslands. With this evidence from morphology and phylogenomic data, we propose the inclusion of the previously unplaced Kampochloa into the subtribe Cteniinae. [ABSTRACT FROM AUTHOR]

Hordeum pusillum (Hordeum pusillum Nutt., 1818) is an annual barley that is native to the west of the North America and widespread in southern United States and tropical America. In this study, we have provided the first complete characterization of the chloroplast genome of H. pusillum. Our research revealed that the circular chloroplast genome of H. pusillum consists of a large single-copy region (LSC: 80,853 bp), a small single-copy region (SSC: 12,745 bp), and a pair of inverted repeat regions (IRs: 21,587 bp), totaling 136,772 bp in length. Within the chloroplast genome of H. pusillum, 91 protein-coding genes, 38 tRNA genes, and ten rRNA genes were identified. To determine the evolutionary relationship of Hordeum species with reported chloroplast genome sequences, we constructed a phylogenetic tree using the entire chloroplast genome sequences. The evolutionary position of H. pusillum corresponds to its geographical location. The chloroplast genome of H. pusillum provided in this study may have significant implications for the phylogenetic study of Poaceae species. [ABSTRACT FROM AUTHOR]

Plantago lanceolata L. (plantain) increases herbage dry matter (DM) production and quality during warm and dry conditions due to its deep roots and drought tolerance and reduces nitrogen losses in grazing systems compared to traditional pastures. However, plantain density usually declines after the third growing season, mainly due to defoliation management. The effects of defoliation frequency and intensity on water-soluble carbohydrate (WSC) reserves and below-ground plant responses need further research to optimize grazing strategies for improved productivity and sustainability of grazing systems. Our study investigated the effects of defoliation frequencies (15, 25, and 35 cm of extended leaf length, ELL) and intensities (5 and 8 cm of residual heights) on morphological traits and WSC concentrations in plantain biomass under controlled environmental conditions. Defoliation frequency significantly influenced morphological and chemical characteristics and biomass distribution more than residual height. Less frequent defoliations promoted above-ground herbage DM production, reproductive stems, and root biomass. Root architecture showed adaptations in response to defoliation frequency, optimizing resource acquisition efficiency. Frequent defoliation reduced high molecular weight WSC concentrations in leaves, affecting regrowth capacity and DM mass. A defoliation frequency of 25 cm ELL (~15 days) balances herbage production and root development, promoting long-term pasture sustainability. [ABSTRACT FROM AUTHOR]

Rice grown in cadmium (Cd)-contaminated soil, is a potential threat to human health, but exogenous selenium (Se) application on rice can mitigate Cd toxicity. However, the mechanisms underlying Se mitigation of Cd stress in ratoon rice (RR) are still poorly understood. We conducted a pot experiment with moderate Cd-contaminated yellow–brown paddy soil on two rice varieties 'Taoyouxiangzhan' (TX) and 'Liangyou 6326'(LY). For all treatments, 1.0 mg kg−1 sodium selenite solution was added to soil. Treatment T1 was sodium selenite only, and in the other treatments 100 mg L−1 Se solution was sprayed on the leaves at seedling stage (T2), at tillering stage (T3), and in early anthesis stage (T4). Se treatments decreased Cd accumulation in rice grains and herbage. Under foliar spraying 100 mg L−1 Se at the seedling + 1.0 mg kg−1 Se in soil (T2), leaf Cd content decreased 16.95% in the current season and grains content decreased 46.67% in the subsequent season. Furthermore, grain Se content increased 0.94 mg kg−1 for the TX variety combined with the analysis of Cd bio-accumulation factor in grains, and Se treatments effectively decreased Cd grain concentrations due to reduced Cd translocation from roots to grains. TX variety rice showed a more pronounced response to Se treatments than LY. [ABSTRACT FROM AUTHOR]

Reduced reliance on inputs such as fertilizer is fundamental to sustainable grazing systems. This two‐year study compared four sward types, including multispecies swards (MSS), for herbage dry matter (DM) production, species contribution to DM, and herbage nutritive value under grazing. The systems were: (1) Lolium perenne L. monoculture (PRG; 170 kg N ha−1 year−1); (2) permanent pasture (PP; 135 kg N ha−1 year−1), (3) six species sward consisting of two grasses, two legumes and two herbs (6S; 70 kg N ha−1 year−1), (4) twelve species sward consisting of three grasses, four legumes and five herbs (12S; 70 kg N ha−1 year−1). Herbage samples were collected for DM yield, botanical composition, and nutritive value. Mean annual DM production for PRG, PP, 6S, and 12S was 11,374, 8526, 13,783, and 13,338 kg DM ha−1 respectively. Herb proportions decreased in 6S and 12S from 2020 to 2021 while grass proportions increased. Mean crude protein levels were similar across all systems (p > 0.05), with higher ash content in 6S and 12S compared to PRG (p < 0.001). Organic matter digestibility was lowest in PP compared to PRG (p < 0.001) while neutral detergent fibre content of PP and PRG were greater than 6S and 12S (p < 0.001). Water soluble carbohydrate content was highest in PRG (p < 0.0001). Over 2 years, MSS delivered increased herbage DM yield and nutritive quality relative to PRG and PP swards, from reduced N inputs. However, maintenance of the herb component of MSS is a challenge. [ABSTRACT FROM AUTHOR]

Background: Mixtures with birdsfoot trefoil (BFT) increase herbage intake in grazing cattle. We hypothesized that BFT spatially separated from grasses would increase preferential grazing of BFT and herbage intake compared to grass and BFT in mixed rows. Methods: Binary mixtures of BFT were established with orchardgrass, meadow bromegrass, tall fescue, and perennial ryegrass in alternating and in mixed rows. Pastures were rotationally stocked with Jersey heifers, and herbage mass, intake, and preferential grazing were estimated. Results: Planting BFT in alternating rows did not affect herbage mass, intake, or BFT preference. Regardless of spatial arrangement, pasture production averaged 4116 kg ha−1 per rotation, of which 32% was BFT. BFT comprised 39% of herbage intake in alternating and mixed rows, 7% greater (p = 0.001) than offered, indicating partial preference for BFT. Greatest preferential grazing of BFT was in tall fescue and orchardgrass mixtures, but less than commonly reported for legumes grown in more contrasting spatial arrangements with cool‐season grasses. Conclusions: Grazing heifers showed partial preference for BFT over grass. However, the lack of an effect of spatial arrangement on herbage mass, herbage intake, and diet preference indicates that spatial arrangements greater than alternating rows may be needed to increase overall herbage intake. [ABSTRACT FROM AUTHOR]

Arundo donax (family: Poaceae) is a perennial rhizomatous plant with considerable economic and ecological benefits. The plant is characterized by its fast growth, high yield, wide adaptability, and strong disease resistance. However, widespread cultivation is difficult because A. donax can only be asexually propagated. This study tested the efficacy of an aqua-based culture method with short duration and high rooting rate. The aqua-based culture protocol involved treating cane fragments with the commercial broad-spectrum rooting powder ABT-1 (No. 1 of the ABT series) at 100 mg/L for 24 h, followed by culturing in tap water for 19 days. We found that plant materials sampled from September to February of the following year were more suitable for aqua-based culturing than materials sampled from other months. Nodes on different parts of the cane did not vary significantly in the ability to form seedlings. The rooting percentage reached >95% after only 20 days, while the sprouting percentage was >93%. The seedlings obtained were strong, with high survival rates during cultivation and acclimation. No strict requirements for the growing media were necessary to achieve these results. In conclusion, this study provides an empirical foundation for a technique that could facilitate the factory production of high-quality A. donax seedlings. [ABSTRACT FROM AUTHOR]

Statistical morphological variations at the population level serve as a robust foundation for species delimitation and taxonomic treatment. We employed this approach to investigate species delimitation within the Ptilagrostis dichotoma species complex (Poaceae), which is characterized by open panicles. While three species have been described, the boundaries between these species and the morphological distributions of all taxonomic traits remain unclear. In this study, we examined the geographical variability of 19 morphological traits based on at least six individuals from each of the 28 populations across the entire distributional range of the species complex. Our statistical analyses identified five distinct phenotypic clusters with specific geographical preferences. Three of these clusters corresponded to the previously described species, while the remaining two clusters represented previously undescribed species. Furthermore, our findings highlight several traits, such as basal leaf scabrosity, panicle branch pulvinae, and glume length, which exhibit distinct gaps between phenotypic units and prove highly valuable for species delimitation. Finally, two new species are described and a key is provided to differentiate the five species. This morphological revision establishes a basis for future studies on species boundaries and divergences of the complex based on other evidence. [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]

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

Livestock farming in the Peruvian tropics is based on the use of grazing forage, but cutting grasses offers greater productivity and seasonality advantages. In this study, the morphological and productive characteristics of King Grass Morado (KGM), Cuba OM-22 (CU), and Maralfalfa (MA) were evaluated and correlated with chlorophyll content under Peruvian humid tropic conditions. Five plots of 1 ha each were installed for the three Pennisetum varieties (2-1-2), with three samples per plot. No significant differences were found in plant height, leaf length, number of nodes, number of leaves/stem, number of stems, stem circumference, length of nodes, leaf, stems, and total weight, chlorophyll index (atLEAF CLOR), performance index (API), and dry matter. KGM stood out in tillering (12.86) (p<0.01), but CU and MA showed greater leaf width (4.16 and 4.42 cm, respectively) (p<0.05). The calculated biomass production was 40.3 t/ha for KGM, 24.5 t/ha for MA, and 76.5 t/ha for CU. MA had higher nitrogen (0.70%) and protein (4.33%) contents (p<0.01). The correlations were significant between stem height with the number of nodes and leaf width, stem circumference with stem, leaf, and total weight (p<0.05), and nitrogen and protein content were estimated with the atLEAF CLOR and API values of the basal leaves with R2 = 0.548 and R2 = 0.563, respectively (p<0.05). In conclusion, KGM, CU, and MA differed in some morphological and productive variables and were correlated with others; furthermore, the protein content could be estimated with the atLEAF CLOR and API values in these Pennisetum varieties. [ABSTRACT FROM AUTHOR]

This study was carried out to characterize the dynamics of forage accumulation during the regrowth of Mulatto grass submitted to rotational grazing strategies. The treatments corresponded to combinations between two pre-grazing conditions (95% and a maximum light interception during regrowth—LI95% and LIMax) and two post-grazing conditions (post-grazing heights of 15 and 20 cm), according to a 2 × 2 factorial arrangement and randomized complete block design, with four replications. Rates of leaf growth (LGR), stems growth (SGR), total growth (TGR), leaf senescence (LSR), grass accumulation (GAR) (kg·ha−1·day−1), and the senescence/canopy growth ratio during different stages of regrowth. There was no difference between the management strategies for TGR. However, a higher GAR was reported for pastures managed with LI95% relative to LIMax, of 161.7 and 120.2 kg DM ha−1·day−1, respectively. Pastures managed with LI95% have a lower SGR in the intermediate and final regrowth period, reflecting the efficient control in the stalks production. On the other hand, in pastures managed, the LIMax showed higher SGR and LSR in the final regrowth phase. Thus, the LAI was higher in pastures managed at LI95% compared to those managed at LIMax, of 163.9 and 112.7 kg DM ha−1·day−1, respectively. Mulatto grass pastures, which were managed at LI95% pre-grazing, corresponded to approximately 30 cm in height, showed higher LAI, and ensured a low SGR throughout the regrowth period, constituting a more efficient management strategy. [ABSTRACT FROM AUTHOR]

Simple Summary: The implementation of new strategies for the reduction of methane emissions by cattle is necessary. Iodoform is an additive that has the potential to inhibit methane production during digestion in ruminants. The present research investigated the effect of iodoform on maize silage and clover grass silage in four 22 h in vitro gas production fermentations with periodic gas chromatography sampling. Iodoform decreased organic matter degradation in both substrates but only significantly in grass silage. The total volatile fatty acid production increased, and the profile was altered, but only significantly in grass silage. There were consistently opposite effects of 0.032 mg/g of dry matter substrate of 0.064% iodoform in zeolite on total gas production and methane production in the two substrates, although not all differences were significant. Iodoform decreased total gas production and methane yield when added to grass silage but consistently and significantly increased both total gas and methane yield when added to maize silage. The efficiency of microbial conversion decreased significantly when iodoform was added to both substrates. These results show differential effects of iodoform on maize silage and clover grass silage and suggest that more research is needed to study the mechanism of methane reduction by iodoform in enteric methane production. Iodoform has been shown to be an enteric methane-reducing agent. This study aimed to investigate if iodoform differentially affected maize (MS) and clover grass silage (GS). These substrates were used in four 22 h in vitro gas production fermentations with and without 0.032 mg/g of dry matter substrate of 0.064% iodoform in zeolite (IZ). The results of organic matter degradation (dOM, g/g), volatile fatty acids (VFAs, mMol/L), partitioning factor (PF, mg/mL), total gas production (TGP, mL/g OM), and periodic hydrogen and methane yield (mL/g OM) were evaluated. The interaction between substrate and IZ for dOM was significant with significantly less in GS. The interaction between substrate and additive was continuously significant for TGP. The additive in GS numerically decreased the TGP, but significantly increased TGP in MS. The interaction between substrate and additive was sporadically significant with methane, increasing the yield when IZ was added to MS, but a consistent, non-significant, decrease in yield was found when IZ was added to GS. Total VFA production and propionate content increased in both substrates with the addition of IZ, but only significantly in GS. Iodoform significantly decreased the efficiency of microbial conversion (PF) in both substates. Differential effects of iodoform on GS and MS were evident. More research is needed to determine the modes of action of iodoform. [ABSTRACT FROM AUTHOR]

Bermudagrass [Cynodon dactylon (L.) Pers.] is an important forage source for ruminants in tropical and subtropical regions of the world; nevertheless, little is known about the productive and nutritional characteristics of new accessions and cultivars originating from breeding programs. Five bermudagrass cultivars (Tifton 85, Jiggs, Florida 44, Callie, and Newell) and five accessions (276, 282, 323, 286, and Missouri) were tested during the 2018 and 2019 growing seasons. Genotype × harvest interactions were detected for herbage accumulation (HA), crude protein (CP), and nitrogen yield (p < 0.05). In June, all bermudagrass genotypes showed significant variation in HA, with accession 286 being more productive than Jiggs (4.42 vs. 3.24 Mg DM ha−1 harvest−1, respectively, where DM is dry matter). In October, however, accession 323 had greater CP than Callie, accession 286, Newell, and Tifton 85, with average CP values of 155, 128, 136, and 137 g kg−1 DM, respectively. Average in vitro digestible organic matter for accession 323 (450 g kg−1 DM) was similar to that of Tifton 85 and Newell but greater than that of Missouri (393 g kg−1 DM). Genotypes displayed unique responses to all traits across harvest dates. According to the principal component analysis, the accession Missouri exhibited low productive and nutritive value properties. The accession 286 showed greater CP concentration while still productive; thus, this accession will be further examined for future release to livestock or hay producers in subtropical regions worldwide. [ABSTRACT FROM AUTHOR]

Themeda triandra (Forssk.) is a tussock grass of international importance for its keystone role in grassy ecosystems and, hence, is often a focus for seed production, research and ecological restoration. However, these applications can be challenged by its seed biology, including seed dormancy and the variability of seed traits among populations. The literature on these topics has not been well synthesised. To address this, we reviewed the relevant literature for Themeda triandra seed and found that seed quality is often poor but highly variable, and there are no current quality-assurance standards. Seed characteristics such as weight, awn length and desiccation tolerance can vary with seed ploidy (i.e. the number of chromosome sets). Germination rates of fresh Themeda triandra seed can be as low as 5%, which may be due to seed dormancy. Dormancy varies among populations and with seasonal conditions, and a period of dry storage at room temperature for 8–10 months may be needed before it will reach its full germination potential. No single treatment is effective in overcoming dormancy across all populations. The application of gibberellic acid can increase germination by ~30% in some populations. Although plant-derived smoke products can be effective, they also lack standardisation. Other treatments including the application of heat, or wet–dry cycling warrant further investigation. We recommend the standardisation of Themeda triandra seed testing and labelling, which would allow end users to assess value for money when purchasing seed commercially. Kangaroo grass (Themeda triandra), a tussock grass with an international distribution, plays an important role in grassy ecosystems; however, since colonisation, it has decreased or been degraded across much of its range. It can be re-established from seed but seed quality has high population variability and seed dormancy can be a problem. With increasing calls for native-seed quality-assurance labelling, we show that this could be standardised for Themeda triandra. Photograph by Ellen Bennett. [ABSTRACT FROM AUTHOR]

Plant Snakin/GASA and defensin peptides are cysteine-rich molecules with a wide range of biological functions. They are included within the large family of plant antimicrobial peptides (AMPs), characterized by their structural stability, broad spectrum of activity, and diverse mechanisms of action. The Dilatata group of Paspalum includes five allotetraploids that share an equivalent genomic formula IIJJ. From RNA-seq data of seedling tissues, we performed an in silico characterization of the defensin and Snakin/GASA genes in these species and diploids with a II and JJ genome formula and studied the evolutionary consequences of polyploidy on the expression of the two AMPs families. A total of 107 defensins (distributed in eight groups) and 145 Snakin/GASA (grouped in three subfamilies) genes were identified. Deletions, duplications and/or gene silencing seem to have mediated the evolution of these genes in the allotetraploid species. In defensin genes, the IIJJ allopolyploids retained the I subgenome defensin copies in some of the identified groups supporting the closeness of their nuclear genome with the I subgenome species. In both AMPs families, orthologous genes in tetraploids exhibit higher similarity to each other than with diploids. This data supports the theory of a single origin for the allotetraploids. Several copies of both defensin and Snakin/GASA genes were detected in the five polyploids which could have arisen due to duplication events occurring independently during the diploidization processes in the allotetraploid taxa. [ABSTRACT FROM AUTHOR]

During an ongoing survey on fungal diversity in Sichuan Province, China, a white filamentous fungus growing on decaying marbled bamboo (Chimonobambusa marmoreal) leaves was collected. Upon conducting the initial morphological diagnosis and BLASTn searches, the new collection was assigned to the genus Arthrobotrys. A multi-locus phylogeny, based on a concatenated dataset (SSU-ITS-LSU-TEF1-RPB2), revealed the new collection in close phylogenetic proximity to Arthrobotrys eryuanensis and A. hyrcanus. However, they differ in shape and size of conidia. The conidia of the new collection are comparatively shorter than those of A. hyrcanus and wider than those of A. eryuanensis. Based on the difference in morphology and molecular data, we proposed the new collection as a new species, Arthrobotrys chinensis sp. nov. Detailed morphological characteristics, illustrations, and an updated phylogeny is provided for the new species. [ABSTRACT FROM AUTHOR]

The experiment aimed to screen for high-yielding hybrid combinations of male-sterile alfalfa lines. A total of 10 hybrid combinations were prepared with one alfalfa male sterile line (MS-GN) as the female parent and 10 excellent alfalfa plants (Alfalfa 354-05, Cavalier-02, Gannong NO. 8-04, Alfalfa 440-02, Queen-25, Alfalfa 319-01, Longdong Alfalfa-06, Alfalfa 343-02, Algonkin-19, and Suntory-74) as the male parents, and the numbers were M×1, M×2, M×3, M×4, M×5, M×6, M×7, M×8, M×9, and M×10. The high-yield hybrid combinations were screened by measuring the plant height, stem diameter, primary branch number, fresh yields and hay yields of the F1 generation of the hybrid combination for two consecutive years, combined with the analysis of general compounding ability. The results showed that M×4 had the highest two-year average plant height, which was significantly higher than that of M×7, M×3, M×5, M×8 and M×10 (P<0.05). The two-year average stem diameter of M×6 was the highest, and the two-year average primary branch number of M×1 was the highest. M×1 and M×6 had the highest two-year average hay yield of 2.02 kg/plant, while M×4 and M×1 had the highest two-year average hay yield of 0.60 kg/plant. Plant height, stem diameter, and primary branch number were positively correlated with grass yield, and plant height and primary branch number were significantly or extremely correlated with fresh yield and hay yield (P<0.05 or P<0.01). The cluster analysis of yield traits divided the hybrid combinations into four categories, among which the combinations with better yield traits were M×1, M×6, and M×4, which were consistent with the results of the comprehensive analysis of grey correlation degree. In the general compounding ability (GCA) effect value, M×4 had the highest plant height, M×6 had the highest stem diameter, M×1 had the highest number of first-order branches, M×1 and M×6 had the highest yield, and M×1 and M×4 had the highest hay yield. The results showed that M×1, M×4, and M×6 had better comprehensive performance in yield traits among the hybrid combinations, and they were high-yield hybrid combinations. [ABSTRACT FROM AUTHOR]

Methane fermentation, which is one of the key processes in biogas production, plays an important role in the conversion of biomass to energy. During this process, changes occur in the chemical composition of organic feedstocks, including the chemical composition of grasses. The assessment of these changes is crucial for the efficiency and productivity of biogas production. The material for this study comprised fully mature grass blades with leaves and inflorescences and was collected from extensively used meadows and pastures, as well as cultivated and set-aside areas in the Wielkopolskie Voivodeship, the communes of Białośliwie and Trzcianka, Poland. The aim of this study was to compare methane fermentation efficiency in nine grass species and identify the biomass component involved in biogas production. The results indicate that the fermentation process, as expected, changed the cellulose content. The lignin content of the grasses before fermentation varied more than the cellulose content. The content of holocellulose (sum of carbohydrate components) in the grasses ranged from 59.77 to 72.93% before fermentation. Methane fermentation significantly reduced the carbohydrate content in the grasses, with a low degree of polymerization. Grassland biomass-based biogas production is a viable alternative to conventional fossil fuels. [ABSTRACT FROM AUTHOR]

Summary: The homology of the single cotyledon of grasses and the ontogeny of the scutellum and coleoptile as the initial, highly modified structures of the grass embryo are investigated using leaf developmental genetics and targeted transcript analyses in the model grass Zea mays subsp. mays.Transcripts of leaf developmental genes are identified in both the initiating scutellum and the coleoptile, while mutations disrupting mediolateral leaf development also disrupt scutellum and coleoptile morphology, suggesting that these grass‐specific organs are modified leaves.Higher‐order mutations in WUSCHEL‐LIKE HOMEOBOX3 (WOX3) genes, involved in mediolateral patterning of plant lateral organs, inform a model for the fusion of coleoptilar margins during maize embryo development.Genetic, RNA‐targeting, and morphological evidence supports models for cotyledon evolution where the scutellum and coleoptile, respectively, comprise the distal and proximal domains of the highly modified, single grass cotyledon. [ABSTRACT FROM AUTHOR]

The pollen wall protects pollen during dispersal and is critical for pollination recognition. In the Poaceae family, the pollen exine stereostructure exhibits a high degree of conservation with similar patterns across species. However, there remains controversy regarding the conservation of key factors involved in its formation among various Poaceae species. EPAD1, as a gene specific to the Poaceae family, and its orthologous genes play a conserved role in pollen wall formation in wheat and rice. However, they do not appear to have significant functions in maize. To further confirm the conserved function of EPAD1 in Poaceae, we performed an analysis on four EPAD1 orthologs from two distinct sub-clades within the Poaceae family. The two functional redundant barley EPAD1 genes (HvEPAD1 and HvEPAD2) from the BOP clade, along with the single copy of sorghum (SbEPAD1) and millet (SiEPAD1) from the PACMAD clade were examined. The CRISPR-Cas9-generated mutants all exhibited defects in pollen wall formation, consistent with previous findings on EPAD1 in rice and wheat. Interestingly, in barley, hvepad2 single mutant also showed apical spikelets abortion, aligning with a decreased expression level of HvEPAD1 and HvEPAD2 from the apical to the bottom of the spike. Our finding provides evidence that EPAD1 orthologs contribute to Poaceae specific pollen exine pattern formation via maintaining primexine integrity despite potential variations in copy numbers across different species. [ABSTRACT FROM AUTHOR]

One of the most effective means of increasing urban green areas is the establishment of roof gardens. They have many positive properties and ecological functions, such as filling empty spaces with plants, protecting buildings, dust retention and air cleaning. In the case of extensive constructions, mostly Sedum species are used, planted as carpet-like "grass" sods or by installing modular units as plugs; however, with the use of other plant genera, the efficiency of ecological services could be increased by expanding the diversity. Festuca taxa have good drought resistance, and these plants tolerate temperature alterations well. Their application would increase the biodiversity, quality and decorative value of roof gardens. Experiments were carried out on nursery benches imitating a roof garden, with the use of modular elements intended for Sedum species, which facilitate the establishment of green roofs. In our trial, varieties of two European native species, Festuca glauca Vill. 'Uchte' and F. amethystina L. 'Walberla', were investigated. In order to find and determine the differences between the cultivars and the effects of the media (leaf mold and rhyolite tuff), we drew inferences after morphological (height, circumference, root weight, fresh and dry weight) and physiological tests (peroxidase and proline enzyme activity). We concluded that F. glauca 'Uchte' is recommended for roof garden conditions, planted in modular elements. Although the specimens were smaller in the medium containing fewer organic components than in the version with larger amounts, they were less exposed to the effects of drought stress. This can be a key factor for survival in extreme roof gardens or even urban conditions for all plants. [ABSTRACT FROM AUTHOR]

The incorporation of dual‐purpose alfalfa (Medicago sativa L.) cultivars into bermudagrass (Cynodon spp.) is a viable option to extend the grazing season in Southern forage systems. However, data are limited on which harvest management strategy (HMS) optimizes the use of alfalfa‐bermudagrass (ABG) mixtures in the Southern US. A two‐year study evaluated ABG mixtures under three HMS [cut only (CO), graze only (GO), or cut and graze (CG)].in Headland, AL and Tifton, GA. Alfalfa‐bermudagrass mixtures utilized in this evaluation were ‘Bulldog 805’ alfalfa that was interseeded into ‘Tifton 85’ bermudagrass. Treatments were evaluated for forage, animal, and total system performance. Herbage accumulation varied by year and location (p < .01), but the number of harvests ultimately determined the total forage produced. Forage allowance was never limiting but did differ among treatments at Tifton, GA (p = .02). The CG HMS allowed for similar daily (p > .06) and liveweight gains (p > .56) on fewer days of grazing as compared to the GO treatments. The greater alfalfa percentage in the CG HMS translated to greater total digestible nutrients (TDN) and crude protein (CP), though not always statistically different. The CO HMS maximized system performance when evaluated for total gain (actual gains + predicted gains). However, the CG management allowed for more production opportunities across the season, thereby reducing economic risk. Future research should focus on evaluating the economic implications of introducing each HMS into ABG systems. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of environmental disturbances on the stoichiometry characteristics of plants in degraded alpine meadows. To achieve this, a mowing experiment was conducted on an alpine meadow with three degradation levels [light degradation (LD), moderate degradation (MD), and severe degradation (SD)] in Shangri-La from 2018 to 2020. Subsequently, differences in plant carbon (C) content, nitrogen (N) content, phosphorous (P) content, C: N P ratio, and N-P power function relationship among different mowing durations (0, 1, 2 a, respectively) were analysed. The results were as follows: (1) Except for the P content of Cyperaceae, plant C, N and P contents of the entire plant community, Gramineae and forbs did not vary among degradation levels (P > 0.05) during the mowing experiment. Plant C, N and P contents tended increase and then decrease with increasing mowing years, i.e., these indices were the highest after 1 a of mowing (P < 0.05) . (2) At the plant community and functional group levels, there was no significant difference in plant C: N ratio and C: P ratio among degradation levels (P > 0.05) . From LD to SD, the N P ratio of the plant community, Cyperaceae and forbs tended to decrease slightly first and then increased (P < 0.05), while the N P ratio of Gramineae did not change significantly (P > 0.05) (3) The N: P ratio and C P ratio showed a parabolic trend, while the C: N ratio showed an inverse trend with the increasing of mowing duration. Before mowing (i.e., mowing 0a), the C: P ratio and N P ratio of Cyperaceae were higher than those of forbs (P < 0.05) but did not vary from those of the plant community and Gramineae (P > 0.05) . After mowing (i.e., mowing 1 a or 2 a), the C: P ratio and N P ratio of Cyperaceae were higher than those of the whole plant community, Gramineae, and forbs (P < 0.05) At each mowing duration, the C N ratio of plants did not vary among plant communities and functional groups (P > 0.05) . (4) Mowing caused a stronger N-P power function relationship and a stable power exponent bot both at the plant community and functional group levels. And the N-P power exponent of Cyperaceae was less than 0.1, while those of the plant community, Gramineae and forbs remained stable at 0.19- 0.22. In conclusion, this study found that plant stoichiometry remained stable across degradation levels but changed significantly with the prolongation of the mowing duration, which implies that different degraded alpine meadows in Northwest Yunnan may share common response mechanisms to mowing disturbance. [ABSTRACT FROM AUTHOR]

Torilis samia sp. nova (Apiaceae) is described from Mt Karvounis (Ambelos) on the East Aegean island of Samos. It resembles T. ucranica but differs clearly by its heterocarpic fruits. The mericarps of the outer fruits have long, flexuous patent-spreading spines. The fruits of T. ucranica are homomorphic and the outer mericarps have upwardly curved adpressed spines. The second species, Ehrharta erecta (Poaceae) is an alien with a native distribution range from Eritrea to South Africa, Réunion, the Arabian Peninsula and India. It is reported for the first time in Greece. Both taxa are illustrated by photographs. The distribution of T. samia and T. ucranica in Greece is mapped. [ABSTRACT FROM AUTHOR]

It aimed to estimate the forage intake by lambs managed in different leaf allowances on Brachiaria-grass using internal and external markers. Forty-eight Texel lambs with 17.52 ± 3.48 kg were evaluated which were 12 testers and 36 regulators. The lambs were kept in twelve paddocks, subdivided into four treatments based on green leaf allowance (60, 75, 90, and 105 g/kg of BW). The experimental design was completely randomised. To estimate dry matter intake (DMI), the following markers were used: indigestible dry matter (iDM); indigestible neutral detergent fibre (iNDF); indigestible acid detergent fibre (iADF); lignin in indigestible acid detergent (iADL) and titanium dioxide (TiO2). Comparisons between intake markers were made using Chromic Oxide (Cr2O3) as a control marker. The leaves allowance tested did not alter the voluntary intake by lambs kept in Brachiaria-grass pasture. Comparison between the control intake marker (Cr2O3) and the other markers by Dunnett's test showed that, regardless of green leaf allowance, the Cr2O3, TiO2 and iADL markers provided similar estimates of DMI, but with lower values than the other markers. External marker TiO2 and the internal iADL were demonstrated to be more suitable for estimating the dry matter intake in grazing lambs regardless of the leaf allowance. [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]

Phyllachora (Phyllachoraceae, Phyllachorales) species are parasitic fungi with a wide global distribution, causing tar spots on plants. In this study, we describe three newly discovered species: Phyllachora chongzhouensis, Phyllachora neidongensis, and Phyllachora huiliensis from Poaceae in China. These species were characterized using morphological traits and multi-locus phylogeny based on the internal transcribed spacer region (ITS) with the intervening 5.8S rRNA gene, the large subunit of the rRNA gene (LSU), and the 18S ribosomal RNA gene (SSU). Three known species of P. chloridis, P. graminis, and P. miscanthi have also been redescribed, because, in reviewing the original references of P. chloridis, P. graminis, and P. miscanthi, these were found to be relatively old and in Chinese or abbreviated. In addition, the illustrations were simple. In molecular identification, the ITS sequence is short, while the ITS, LSU, and SSU are incomplete. Therefore, this study provides new important references for the redescription of three known species and provides further evidence for the identification of new taxa. [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]

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]

Tripogon salunkhei sp. nov., is described and illustrated from the Sinnar tehsil of Nashik district, Maharashtra state, India. The new species is very distinct among the species of Tripogon Roem. & Schult by all spikelets having two florets. Coloured photographs, distribution, and ecological notes of the new species are provided. [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]

The C4 Poaceae are a diverse group in terms of both evolutionary lineage and biochemistry. There is a distinct pattern in the distribution of C4 grass groups with aridity; however, the mechanistic basis for this distribution is not well understood. Additionally, few studies have investigated the functional strategies of co‐occurring C4 grass species for dealing with aridity in their natural environments. We explored the coordination of leaf‐level gas exchange, water use, and morphology among five co‐occurring semiarid C4 grasses belonging to divergent clades, biochemical subtypes, and size classes at three sites along a natural aridity gradient. More specifically, we measured predawn and midday water potential, stomatal conductance, water use efficiency, and photosynthesis. Leaf tissue was also collected for the analysis of stable isotopes of carbon and oxygen as well as for measurement of specific leaf area (SLA) and leaf width. Species differences in responsiveness of stomata to changes in vapor pressure deficit (VPD) were also assessed. It was expected that NAD‐me species would maintain higher rates of photosynthesis, higher water use efficiency, and have more responsive stomata than other co‐occurring species based on observed biogeographic patterns and past greenhouse studies. We found that Aristidoideae and Chloridoideae NAD‐me‐type grasses had greater stomatal sensitivity to VPD, consistent with a more isohydric strategy. However, midgrasses had both greater apparent water access and water use efficiency, regardless of subtype or lineage. PCK‐type species had less responsive stomata and maintained lower levels of photosynthesis with increasing aridity. There were strong interspecific differences in δ13C, leaf width, and SLA; however, these were not significantly correlated with water use efficiency. C4 grasses in our study did not fit discretely into functional groups as defined by lineage, biochemistry, or size class. Interspecific differences, evolutionary legacy, and biochemical pathway are likely to interact to determine water use and photosynthetic strategies of these plants. Control of water loss via highly responsive stomata may form the basis for dominance of certain C4 grass groups in arid environments. These findings build on our understanding of contrasting strategies of C4 grasses for dealing with aridity in their natural environments. [ABSTRACT FROM AUTHOR]

Silage preservation is critical for livestock's stable forage supply during cold seasons and fostering the recycling of agricultural byproducts. We assessed the effects of adding previously fermented juices (PFJ) and different proportions of Sorghum Sudanense (Piper) Stapf (Sudan grass) on the silage quality of Medicago sativa L. (alfalfa). A 50% alfalfa and 50% Sudan grass (M50) mixture exhibited superior performance in sensory evaluation and fermentation quality. The addition of PFJ (PFJI group) further enhanced quality, and increasing the proportion of alfalfa improved the nutritional quality. However, PFJI had no significant effect on the degradation rates of these nutritional indicators (p > 0.05). As alfalfa proportion increased, the disappearance rates of dry matter, crude protein, neutral detergent fiber, and acid detergent fiber in silage increased. Principal component, correlation, and membership function analyses revealed that treatment with M50 without PFJ (PFJ0+M50) had the best effect, followed by treatment with 25% alfalfa and 75% Sudan grass (PFJ0+M25) and 100% alfalfa (PFJ0+M0). Therefore, the mixing ratio of alfalfa and Sudan grass should be maintained between 25% and 50% to optimize the nutritional and fermentation qualities of silage. These findings offer crucial guidance for alfalfa silage preparation, promoting enhanced livestock industry productivity and sustainable agricultural development. [ABSTRACT FROM AUTHOR]

An increase in precipitation due to climate change has given rise to the number of landslide occurrences. Vetiver, which is a perennial grass, is becoming increasingly popular all over the world as a vegetation-based soil bioengineering tool for preventing landslides. Sunshine Vetiver grass, also known as Chrysopogon zizanioides is noninvasive and does not compete with other indigenous plants growing in the area. Even though it is a tropical grass, Vetiver can grow in a wide range of climate conditions, including those that are quite harsh in terms of both soil and climate. The roots can grow up to 3 m in length in a dense bushy root network under optimal conditions. In this review, the authors have studied the impact of Vetiver on landslide mitigation as a climate-adaptive slope repair tool based on the research undertaken so far. Furthermore, the authors have addressed the future potential and constraints associated with the use of Vetiver for landslide mitigation. It is seen that the use of Vetiver reduces pore water pressure. The high tensile strength of Vetiver roots provides reinforcement for slopes and enhances soil shear strength. Vetiver increases saturated hydraulic conductivity and reduces surface runoff and slip surface depth. Being a vegetation-based climate-adaptive technology, this grass exhibits great promise in its ability to effectively address landslide problems. However, the magnitude of the root impact diminishes as the depth increases, rendering Vetiver a more promising remedy for shallow landslide occurrences. In addition, Vetiver grass has a wide range of practical uses due to its unique characteristics, which provide additional benefits. Employment of Vetiver is cost-effective compared with traditional engineering methods, and it requires less initial maintenance, which implies that community-based initiatives can effectively address landslide prevention through Vetiver implementation. Practical Applications: Vetiver grass has a long bushy network of roots that can grow up to 3 m in length. The Sunshine Vetiver grass is not invasive and does not compete with indigenous plants. Although Vetiver is a tropical grass, this grass can survive in various climates and soil conditions. Vetiver is a vegetation-based climate-adaptive technology that can prevent slope failure and reduce surface runoff. Additionally, growing Vetiver can generate income for local communities because the fragrant roots can be utilized in the extraction of essential oils for the perfume industry and from the manufacture and trade of other commodities derived from Vetiver. The grass's green leaves contribute to the aesthetic appeal of the landscape. Implementing Vetiver on slopes does not require heavy machinery and is cost-effective compared with traditional engineering methods. It also requires less initial maintenance, making it an ideal solution for community-based initiatives aiming to address slope failure prevention through Vetiver implementation. [ABSTRACT FROM AUTHOR]

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Argentina is the country with the highest proportion of arid and semi-arid ecosystems in Latin America. In the rangelands of Southwestern Buenos Aires (Patagones Department), there is a clear advancement of the agricultural frontier to the detriment of the native forest in this region. Due to rainfall variation and seed acquisition, Thinopyrum ponticum is cultivated as a forage perennial crop in this region. Our objective was to evaluate the performance of T. ponticum as a facilitating crop for the medium-term rehabilitation of natural grasslands in semi-arid areas. The working hypotheses were that: 1) native perennial grass cover increases over the years and 2) diversity and specific richness of the vegetation are enhanced by the duration of Tall Wheatgrass implantation. Data were collected from commercial plots where T. ponticum was shown: recent implantation (5–8 years, RI); medium implantation (13–15 years, MI); and old implantation (20–22 years, OI). Thirty-four species were identified and classified into seven functional groups: Annual grasses, annual herbs, perennial herbs, exotic perennial herbs, perennial forage grasses, exotic perennial forage grasses, perennial forage exotic grasses, and non-forage perennial grasses. Thinopyrum ponticum 's total cover was between RI and OI. Total cover, species richness, and Shannon-Weaver diversity index showed no differences among treatments. Perennial forage grasses exhibited higher cover values in sites with greater implantation age and annual grasses showed the opposite response. Our results indicated that T. ponticum does not invade the sampled plots and enhances the colonization of the planted plots by perennial forage native species. However, even though the herbaceous cover had been recovered, the woody layer which could provide environmental services and specific values for conservation was not. [ABSTRACT FROM AUTHOR]

Perennial grasses have developed intricate mechanisms to adapt to diverse environments, enabling their resistance to various biotic and abiotic stressors. These mechanisms arise from strong natural selection that contributes to enhancing the adaptation of forage plants to various stress conditions. Methods such as antisense RNA technology, CRISPR/Cas9 screening, virus-induced gene silencing, and transgenic technology, are commonly utilized for investigating the stress response functionalities of grass genes in both warm-season and cool-season varieties. This review focuses on the functional identification of stress-resistance genes and regulatory elements in grasses. It synthesizes recent studies on mining functional genes, regulatory genes, and protein kinase-like signaling factors involved in stress responses in grasses. Additionally, the review outlines future research directions, providing theoretical support and references for further exploration of (i) molecular mechanisms underlying grass stress responses, (ii) cultivation and domestication of herbage, (iii) development of high-yield varieties resistant to stress, and (iv) mechanisms and breeding strategies for stress resistance in grasses. [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 grass‐legume intercropping systems have become one of the alternative practices to increase the herbage dry matter yield and quality and to enhance resource usage. The study evaluated the competitiveness of various oat/vetch seed rate proportions using a randomized complete block design (RCBD) with five treatments, replicated five times. Fresh herbage was harvested above the ground and subjected to estimate its dry matter productivity, along with the proximate and fibre compositions were estimated. Relative yield (RY), relative total yield (RYT), relative crowding coefficient (RCC), and aggressivity index (AI) were calculated from the dry matter yield of oats and vetch. The monoculture of oats (100% oats) had the highest herbage DM productivity (5.98 t/ha) similar to the mixed oat/vetch mix plots. The vetch monoculture (100% vetch) and 50 : 50 oat/vetch seed rate proportions had a higher CP content than the oat monoculture (100% oat). The total ash (TA) content was considerably higher for 100% oats and the 75 : 25 oat/vetch mixture, respectively. The ether extract was higher for either of the monocultures of oat and vetch. The neutral detergent fibre (NDF) and acid detergent fibre (ADF) content remained highest at 25 : 75 oat/vetch, while the NDF content was lowest at 100% vetch. The ADF content was the lowest for 50 : 50 oat/vetch. Relative yield (RY) and the relative crowding coefficient (RCC) showed an advantage in yield for 50 : 50 oat/vetch seed rate proportions for dry matter yield. However, oat was more aggressive than vetch in the mixture, except in 25 : 75 oat/vetch. It was confirmed that the 50 : 50 seed rate proportions of oat/vetch could be a promising option to reduce the bulkiness of the oat. Moreover, long‐term comparative studies on agronomic performance of the oat/vetch seed proportions in conventional and abandoned lands are recommended to establish persistent results for oat/legume mixed cropping system. [ABSTRACT FROM AUTHOR]