To investigate salt tolerance in alfalfa （Medicago sativa） germplasm， 30 alfalfa accessions of diverse origins were subjected to salt stress （200 mmol/L NaCl） for 15 days. Responses were evaluated through changes in seedling morphology， photosynthetic parameters， and physiological indices compared to control plants （CK， irrigated with Hoagland nutrient solution）. The results demonstrated that NaCl treatment decreased plant height， leaf area， leaf relative water content， root activity， shoot dry weight， chlorophyll a， chlorophyll b， transpiration rate， stomatal conductance， net photosynthetic rate， intercellular CO₂ concentration， water use efficiency， catalase （CAT） activity， and potassium （K⁺） content relative to CK. Conversely， root dry weight， root-to-shoot ratio， stomatal limitation value， proline content， malondialdehyde （MDA） content， peroxidase （POD） activity， superoxide dismutase （SOD）， sodium （Na⁺） content， and the Na⁺/K⁺ ratio exhibited increases. Regression analysis identified stomatal conductance， root activity， root-to-shoot ratio， and Na⁺ content as critical indicators for salt tolerance evaluation. The clustering analysis based on the comprehensive evaluation value of the membership function shows that the 30 alfalfa accessions were classified into four distinct tolerance categories： high salt-tolerant， moderately salt-tolerant， low salt-tolerant， and salt-sensitive. Accessions 7254 and 7657 exhibited high salt tolerance.

This study employed multivariate statistical methods， including analysis of variance （ANOVA）， principal component analysis （PCA）， correlation analysis， hierarchical cluster analysis， and membership function evaluation， to comprehensively analyze and evaluate five seed morphological traits of 329 wildrye （Agropyron cristatum） accessions conserved in the National Crop GeneBank. The objective was to establish a theoretical framework for the evaluation and innovative utilization of A. cristatum （L.） Gaertn germplasm resources. The results showed that among the five phenotypic traits examined， thousand-seed weight exhibited the highest genetic variation， with a genetic diversity index of 1.880 and a coefficient of variation of 24.56%. The average genetic diversity index for all five traits was 1.752， and the average coefficient of variation of 14.06%. PCA extracted three principal components， explaining 98.750% of the trait variation， with the first three main components contributing 65.555%， 26.162%， and 7.034% respectively， effectively preserving the core genetic information of seed traits. Correlation analysis demonstrated extremely significant positive correlations between seed length with the other four phenotypic traits （P<0.01）. Additionally， significant positive correlations were observed between seed width and both thousand-seed weight and single-seed area （P<0.01）， between thousand-seed weight and seed length-width ratio， as well as between seed length-width ratio and single-seed area. Hierarchical cluster analysis categorized the accessions into four groups： Group Ⅰ （284 accessions， moderate）， Group Ⅱ （41 accessions， small-grained）， and Groups Ⅲ and Ⅳ （two high-quality unique accessions each）. Comprehensive evaluation using the membership function identified B-288， B-243， B-233， and B-250 accessions with excellent performance in seed length， seed width， single-seed area， and thousand-seed weight. In contrast， B-152， B-143， B-128， B-149， B-141， and B-153 accessions exhibited relatively weak performance across multiple traits. In conclusion， seed length， single-seed area and thousand-seed weight were identified as the key morphological indicators contributing to the genetic diversity of A. cristatum germplasm.

Dof （DNA-binding with one finger） transcription factors are plant-specific regulators playing critical roles in plant response to environmental stresses. This study comprehensively identified MrDof gene family based on the genome-wide of Medicago ruthenica. We performed analyses including collinearity assessment， phylogenetic analysis， and chromosomal localization on the Dof family members. Furthermore， by integrating transcriptome data of M. ruthenica under drought stress and qRT-PCR validation， we explored the potential functions of these genes in drought stress responses. The results showed that a total of 33 MrDof genes were identified in M. ruthenica， and the number of amino acids encoded by these genes ranged from 157 to 492 aa. According to the evolutionary relationships among M. ruthenica， Medicago truncatula and Arabidopsis thaliana， these genes were classified into eight distinct groups （Group A， B1， B2， C1， C2.1， C2.2， C3， D1 and D2）. The 33 genes were unevenly distributed across nine chromosomes. Expression pattern analysis demonstrated that five genes （MrDof11， MrDof13， MrDof22， MrDof27， and MrDof30） were significantly induced by drought stress.

Nutrient enrichment is a key driver of plant diversity loss in grassland ecosystems. However， the specific pathways and mechanisms underlying species diversity reduction under different nutrient additions influence remain insufficiently understood. This study investigated the effects of nitrogen （N）， phosphorus （P）， and combined nitrogen and phosphorus （N+P） additions on alpine meadows located on the eastern edge of the Tibetan Plateau， using the natural community as a control. The main objective was to examine changes in species richness， biomass， and light transmission， and to elucidate the direct and indirect mechanisms contributing to species richness decline under these experimental treatments. The results showed as follows：（1） N was identified as the primary limiting nutrient for aboveground biomass. Both N and N+P additions significantly increased aboveground biomass （P<0.05）， primarily due to an increase in the biomass of grasses； （2） N and N+P additions significantly reduced species richness （P<0.05）， whereas P addition alone had no significant effect； （3） The mechanisms underlying the reduction in species richness under N and N+P treatments were consistent and involved both direct effects of nitrogen and indirect effects via increased aboveground biomass， which in turn reduced light availability.

Functional microorganisms are essential for promoting plant growth in the desert steppe ecosystem of Inner Mongolia， offering valuable theoretical support and a scientific foundation for grassland ecological restoration and sustainable management. However， comprehensive research on the species diversity and plant growth-promoting mechanisms of these microorganisms within the rhizosphere and endosphere of forage grasses in this region remains limited. This study employed high-throughput sequencing technology to provide a preliminarily analysis of the rhizosphere bacterial community composition associated with 12 dominant forage grass species in the desert steppe. Five bacterial strains （A1-A3 and B1-B2， respectively）were isolated from endosphere and rhizosphere and screened using nutrient-modified selective media based on the soil nutrient conditions of the experimental site. These strains were identified as Bacillus sp. （B1 and B2）， Promicromonospora sp. （A1）， and Streptomyces sp. （A2 and A3）. Functional characterization revealed these strains exhibited strong nutrient-solubilizing capabilities. Strain A2 demonstrated a soluble phosphorus content of 164.51 mg/L in inorganic phosphorus fermentation broth， while strain A3 showed a soluble phosphorus content of 17.43 mg/L in organic phosphorus fermentation broth. All strains exhibited significant potassium-solubilizing activity. Furthermore， they produced plant growth-promoting hormones and displayed ACC deaminase activity. Strain B1 produced auxin at 26.08 μg/L. ACC deaminase activity ranged from 32.20 to 40.05 U/L for strains A1， A2， A3， and B1. All five strains promoted the growth of Neopallasia pectinata seedlings， particularly in enhancing radicle growth.

Shrub encroachment， which significantly alters structure and function of grassland ecosystems， is a critical ecological issue in China. To obtain a comprehensive and quantitative understanding of the research trends on shrub encroachment research in China， this study conducted a bibliometric analysis using CiteSpace and a meta-analysis based on published literatures on shrub encroachment in China since 1970s. Research on shrub encroachment in China had developed rapidly in recent years， with a primary focus on the drivers of shrub encroachment and its impacts on soil， vegetation， and biodiversity. Studies on shrub encroachment in China had been predominantly conducted in drylands and alpine regions. Major drivers of shrub encroachment included grazing management， climate change， habitat characteristics， and fire. Shrub encroachment was found to have a negative impact on soil quality but a positive effect on community composition， as well as the structure of vegetation and microbial communities in China. The primary management techniques for shrub encroachment included grazing exclusion， grazing management， physical removal， and prescribed burning. This study provides scientific insight into the drivers， impact， and future management strategies for shrub encroachment in Chinese grassland. In the future， it is necessary to strengthen large-scale dynamic assessments of shrub encroachment across diverse grassland types， and integrate remote sensing technology to enhance the scientificity and effectiveness of monitoring and management of encroached landscape in China.

Warming and nitrogen deposition can affect the functions and structures of alpine meadow ecosystems on the Qinghai-Xizang Plateau. Ecological stoichiometry provides a framework to understand the biogeochemical cycling of nutrients between plant and soil. This study conducted a field experiment in an alpine meadow of Qinghai Province， to investigate the effects of different levels of warming and nitrogen deposition. The warming treatment included four levels： W0 （no warming）， W1 （air temperature increases 0.47 °C， soil temperature increases 0.61 °C）， W2 （air temperature increases 0.92 °C， soil temperature increases 1.09 °C）， W3 （air temperature increases 1.44 °C， soil temperature increases 1.95 °C）. Nitrogen application treatments included： N0 （no nitrogen application）， 16 kg N/（hm²·a）， and 32 kg N/（hm²·a）. The experiment assessed changes in carbon， nitrogen， and phosphorus contents in plant and soil， soil enzyme activity， and their stoichiometric ratios， as well as the relationship among these components. The results showed as follows： Warming significantly increased total nitrogen in the aboveground plant tissues， soil total nitrogen， soil organic carbon， the soil nitrogen phosphorus ratio， and the enzyme nitrogen phosphorus ratio. Simultaneously， it significantly decreased the carbon nitrogen ratio in aboveground plant biomass， and the carbon nitrogen and carbon phosphorus ratios of soil enzymes. Nitrogen deposition significantly increased total nitrogen in both aboveground and root tissues， soil organic carbon， soil total nitrogen， and the enzyme carbon nitrogen ratio. It significantly decreased the root carbon nitrogen ratio and enzyme nitrogen phosphorus ratio. The interaction between nitrogen deposition and warming significantly affected soil organic carbon content and the carbon nitrogen， carbon phosphorus， and nitrogen phosphorus ratios of soil enzymes. Analysis of stoichiometric homeostasis in plant tissues in responses to soil elements and enzyme activities revealed strict stoichiometric homeostasis in plant tissues under both warming and nitrogen deposition. Soil total nitrogen， soil carbon nitrogen ratio， and soil β-1， 4-xylosidase activity significantly influenced plant nutrient content and stoichiometry. In summary， short-term warming and nitrogen deposition significantly alter the stoichiometry of soil and enzyme systems in alpine meadows， which in turn influences the nutrient acquisition strategies of plants on the Qinghai-Xizang Plateau.

Salt stress leads to the accumulation of reactive oxygen species （ROS） in plants， causing damage to plant cells. However， the enzymatic antioxidant system is responsible for scavenging ROS in plant cells and protecting cells from ROS damage. At present， there are few functional analyses of genes related to ROS-scavenging enzymes in alfalfa （Medicago sativa） in response to salt stress. Based on the transcriptome data of roots and leaves of salt-tolerant alfalfa cultivar （GIB） and salt-sensitive cultivar （LS） under salt stress， this study identified 28 differentially expressed genes related to ROS-scavenging. Twenty-eight genes are distributed on 19 chromosomes， belonging to five gene families： MsGST， MsPOD， MsAOX， MsGRX and MsPrdx， among which MsGST （12） and MsPOD （11） families account for the largest proportion. The physicochemical properties of ROS scavenging enzyme proteins were different among the members of each gene family. There were highly similar conserved motifs in the members of the gene family. Phylogenetic analysis showed that MsGSTUs and MsPODs were located in the branches defined by Tau and AtPERs in Arabidopsis thaliana， respectively， suggesting that they had similar evolutionary processes and similar functions.Real-time fluorescence quantitative PCR analysis showed that the expression levels of MsGSTU26， MsPOD2 and MsPOD4 genes in GIB leaves under salt stress were significantly higher than those in LS， and the promoter regions of the three genes had elements （G-box and CGTCA-motif） related to adverse stress. It indicated that the MsGSTU26， MsPOD2 and MsPOD4 genes may be involved in the regulation of the adaptability of GIB and LS to salt stress.

Nitrogen deposition represents a critical driver of nitrous oxide （N₂O） emissions in global terrestrial ecosystems， with profound implications for climate change prediction. Although numerous studies have investigated soil N₂O emissions patterns in response to nitrogen addition， controversies persist regarding the regulatory mechanisms and driving factors. Through a meta-analysis intergrading the 87 global studies， we demonstrate that nitrogen addition significantly enhances soil N₂O emissions. This effect is particularly pronounced under high nitrogen application rate （>200 kg/hm² year）， in low-precipitation regions （≤400 mm annual rainfall）， and with short-term and moderate-term nitrogen application （≤3 years）. Our analysis identified nitrogen input level， mean annual precipitation， and ecosystem type as the dominant factors controlling global N₂O emissions， providing a scientific foundation for developing targeted emission mitigation strategies.

Monitoring and evaluation of ecosystem health in nature reserves is a prerequisite for improving the health management of the reserves. To improve the limitations of traditional field survey means， remote sensing indicators were applied in this research to carry out ecosystem health evaluation of grassland ecosystems in nine national nature reserves located in Inner Mongolia. The ecosystem health evaluation index system was constructed based on the three dimensions of vitality， organization and resilience （VOR） by selecting the ideal reference system. In addition， weights of each indicator in different grassland types were calculated by the Critic weight analysis algorithm， and the grassland ecosystem health evaluation and grading levels （excellent-good-moderate-unhealthy） in Inner Mongolia'National Nature Reserves were distinguished. Finally， differences in ecosystem health among the three main grassland types in the reserves， meadow steppe， typical steppe and wetland steppe， were compared for both 2000-2009 and 2010-2019 time periods. Results showed that： （1） All grassland ecosystems in nine National Nature Reserves in Inner Mongolia were healthy， with 22% as excellent， 44% as good， and 33% as medium. （2） Different grassland ecosystems in reserves were all at healthy levels. However， some of the grassland ecosystems in the reserves were still at a moderate level on the dimension of resilience， lower than expected. Thus， enhanced management and protection at the reserve aspect will be required. （3） The ecosystem health of the grassland ecosystems in the reserves was stable and improving in 2010-2019 period compared to 2000-2009. Evaluation indicator system and results in this study can provide important support for health management in reserves and scientific decision-making.

This study investigated the effects of various fertilization treatments on natural mowing grassland in the Altay Mountains， combining field investigations with indoor laboratory analyses. The experiment included four fertilization measures：no fertilization （control）， compound fertilizer， organic fertilizer and bio-bacterial fertilizer. The primary objective was to assess these treatments on grassland plant community characteristics， soil nutrients， and soil microorganisms. The results showed as follows：（1） Compound fertilizer application significantly increased aboveground biomass （P<0.05）， but decreased underground biomass in the 0~10 cm soil layer. Bio-bacterial and organic fertilizers increased species diversity， while compound fertilizer reduced it. Notably， the Shannon-Wiener index was significantly higher under bio-bacterial fertilizer than under compound fertilizer （P<0.05）； （2） Fertilization significantly lowered soil pH and increased soil organic matter content. Organic fertilizer significantly increased available nitrogen content （P<0.05）， while compound fertilizer significantly raised available phosphorus and available potassium concentrations （P<0.05）； （3） Fertilization significantly increased the number of bacterial operational taxonomic units （OTUs） and decreased fungal OTUs （P<0.05）， indicating shifts in microbial community structure and enhanced microbial diversity. A comprehensive evaluation using a membership function approach indicated that compound fertilizer had the most substantial effect in improving degraded natural meadows. These findings provide a scientific basis for enhancing the productivity and soil fertility of natural meadows through appropriate fertilization strategies.

This research focused on four new alfalfa （Medicago sativa） lines （P1， P2， P3， and P4） and local M.sativa cultivar 'Longdong' to explore the changes and response mechanisms under low-temperature conditions. The morphological， physiological， and photosynthetic parameters of seedlings were measured at 0 d （CK）， 1 d， 13 d， and 20 d under low-temperature stress （4 °C）. The results showed that as the duration of low temperature stress increased， plant height， aboveground and belowground biomass， root-shoot ratio， root activity， chlorophyll a， chlorophyll b， carotenoids， total chlorophyll content， transpiration rate， net photosynthetic rate， stomatal conductance， and the contents of auxin， zeatin， and gibberellin in aboveground and belowground were decreased significantly （P<0.05）. Water use efficiency， malondialdehyde content， and aboveground and belowground abscisic acid were significantly risen （P<0.05）. The stomatal limitation value， along with the activities of peroxidase， superoxide dismutase， and catalase showed an initial increase followed by decrease， reaching their peak at 13 d under stress. In contrast， the intercellular CO₂ concentration decreased initially and then increased， with the minimum value occurring at 13 d under stress. The comprehensive evaluation with the membership function indicated that cold resistance was ranked as P4>P2>P1>P3>'Longdong'. Linear regression analysis revealed that aboveground gibberellin， plant height， underground gibberellin， and belowground zeatin can be the preferred indices for evaluating the cold resistance of alfalfa seedlings. These findings provide a theoretical basis for breeding new alfalfa cultivars with cold-resistant.

The response of grassland plants to grazing pressure and their subsequent growth dynamics are critical for maintaining ecosystem stability. As the primary interface for grazing interactions， leaf growth status is not only regulated by external environmental factors， but also significantly influenced by the metabolic activities of epiphytic microorganisms. This research investigated the responses of epiphytic microbial community characteristics of dominate species to grazing in temperate typical grasslands of northern China. High-throughput sequencing technology was applied to analyze the diversity and community composition of phyllosphere bacterial and fungal of Leymus chinensis， Stipa grandis， and Cleistogenes squarrosa. Results showed that：（1） Under both grazing and enclosure conditions， the epiphytic microbial communities of all three plant species were consistently dominated by bacterial phyla including Pseudomonadota， Bacillota， Bacteroidota， Actinobacteriota， and Acidobacteriota， along with fungal phyla Ascomycota and Basidiomycota. Notably， grazing disturbance significantly reduced the relative abundance of Proteobacteria in L. chinensis phyllosphere communities， creating ecological niches for colonization of other microbial taxa. Under grazing conditions， concurrently， a significant reduced in Filobasidium abundance within fungal communities of L. chinensis was observed， This change may reduce the risk of plant disease. （2） Under grazing conditions， the phyllosphere exhibited an enrichment of unique microbial taxa. Thermotogota was detected for the first time in bacterial communities of L. chinensis， while Kickxellomycota was identified as novel colonizer in fungal communities of C. squarrosa. These newly identified microbial taxa may significantly influence the adaptability and functional diversity of phyllosphere microenvironments. （3） The responses of functional classification in phyllosphere fungi to grazing and host specificity were significantly stronger. Under grazing conditions， relative abundance of pathogenic fungal decreased， whereas beneficial fungi increased， indicating that grazing may indirectly suppress pathogen proliferation by altering the phyllosphere microenvironment. In conclusion， effects of grazing directly alters phyllosphere microbial community structure by modifying host plant characteristics and their associated microenvironments， ultimately increasing microbial diversity and the proportion of beneficial microorganisms.

In order to explore the effects of drought stress on agronomic traits of different alfalfa varieties （strains）， 12 alfalfa varieties （strains） were used as materials in this study， pot experiments were carried out in greenhouse and two treatments of drought stress and rewatering were conducted at seedling stage， the agronomic traits （plant height， aboveground fresh and dry weight， root length， root fresh and dry weight， root shoot ratio， stem diameter， root diameter， branch number） of alfalfa materials after treatment were determined， and through the comprehensive drought resistance coefficient， principal component comprehensive evaluation， grey correlation degree and drought resistance index for comprehensive evaluation of drought resistance ability. The results showed that the new strain 1 had the highest drought resistance coefficient in aboveground fresh weight， aboveground dry weight， plant height， root length and branch number， the drought resistance coefficient of stem diameter of new strain 2， the drought resistance coefficient of root diameter of Gannong No.7 and drought resistance coefficient of root fresh weight and root shoot ratio of Zhongtian No.3 were the highest， the drought resistance coefficient of aboveground fresh weight，aboveground dry weight， root fresh weight， root dry weight， plant height， root length and branch number of Zhongmu No.3 was the lowest， the drought resistance coefficient of stem diameter in Gannong No.3 and drought resistance coefficient of root shoot ratio in Zhongtian No.2 were the smallest. The comprehensive drought resistance coefficient， principal component comprehensive evaluation， grey correlation degree and cluster analysis showed that the new strain 1， Zhongtian No.3 and Zhongmu No.1 had strong drought resistance. The drought-resistant germplasms identified by the Drought Resistance Index （DRI） method were new strain 1， Zhongtian No.3， new strain 3， Zhongmu No.1， and Gannong No.7， all of which displayed DRIs greater than 1. Comprehensive evaluation across multiple methods revealed that new strain 1， Zhongtian No.3， and Zhongmu No.1 possessed the strongest drought resistance.

Grassland restoration is a critical pathway toward achieving sustainable utilization and high-quality development goals for degraded ecosystems. While scientific evaluation of restoration outcomes provides essential evidence for optimizing rehabilitation strategies， current methodologies predominantly focus on pre- and post-restoration changes in individual or limited indicators （e.g.， biomass， vegetation coverage）， with insufficient attention to comprehensive multi-indicator assessments. To address this issue， this study used factor analysis to comprehensively evaluate eight restoration approaches and nine ecological restoration effect assessment indicators for degraded grasslands in Chen Barag Banner， Inner Mongolia， aiming to identify representative community assessment indicators and suitable restoration approaches. The findings demonstrated that： （1） Three critical indicators-vegetation coverage， aboveground biomass， and community species richness-were identified as representative metrics for restoration evaluation. （2） The integrated approach combining fencing with root pruning， fertilization， and sustained management practices demonstrated superior restoration effectiveness. Our comprehensive quantitative assessment methodology exhibited both scientific rigor and practical applicability. These findings provide an evidence-based framework for evaluating and managing grassland restoration initiatives in Inner Mongolia's degraded steppes and comparable ecoregions.

Plant rhizosheath is the sheath-like structure tightly adhering to the root surface. The unique physical， chemical， and microbiological characteristics of the rhizosheath contribute to vital environmental and biochemical functions including rhizosphere soil aggregation， formation of soil aggregates， enhanced water and nutrient uptake， promotion of microbial colonization， and drought stress resistance. This review provides comprehensive understanding for the research status about rhizosheath in formation and the function and objectively demonstrates current research hot spot. CiteSpace software and bibliometric methods were conducted to retrieve a total of 2812 publications related to rhizosheath from January 1， 2008， to April 30， 2023 in Web of Science （WOS） Core Collection and China National Knowledge Infrastructure （CNKI） database with key words “Rhizosheath”， “Root hair”，“Root exudate”，‘Root sheath’， ‘Root secretion’， and ‘Root hair’. This review illustrates biological， chemical， and physical interactions determining rhizosheath development and plant absorption of water and nutrient from perspectives of plant rhizosheath formation and function. The review aims to provide guidance for further research on molecular genetic mechanisms of rhizosheath development and the application on crop breeding.

The design of the rules transfer of grassland contracted management rights aims to maximize the benefits of limited land while also protecting the herdsmen's mission. However， in practice， there are many problems in the application of this rule. By studying the grassland contract cases in recent years， this paper summarizes the types of contracts that violate the mandatory provisions of the Grassland Law， including subject violations， content violations， procedural violations， and object violation， in the judicial practice of our country， there are some problems in the determination of the violation of mandatory provisions in the transfer contract of grassland contractual management right， such as an excessively high proportion of invalid contract determinations and inconsistent interpretations of the same legal norms， we should measure the ecological interests and contractual interests of grassland protection in an all-round way by means of interest measurement， ensure the appropriateness of determining the invalidity of contracts under the guidance of the principle of proportionality， and ensure the stability of the market and the security of transactions with the goal of trust interests. Therefore， it is necessary to reshape the effectiveness of contracts that violate the mandatory provisions of the Grassland Law. By reducing the qualifications of grassland contracting entities， reducing the invalid identification of grassland contract management rights transfer contracts， and optimizing the procedural rules of grassland contract management rights transfer contracts， we can achieve sustainable use of grassland resources and protect the rights and interests of herdsmen.

This research aims to investigate the effects of variations in precipitation on the ecological stoichiometry of soil organic carbon （SOC）， total nitrogen （TN）， and total phosphorus （TP） in desert steppes and to reveal the response of C， N， and P and their ecological stoichiometry to precipitation gradients in desert steppe ecosystems. The experiment was conducted in temperate desert steppe on the southern edge of Mu Us Desert， Yanchi County， Ningxia Hui Autonomous Region. Five precipitation levels， 33%， 66%， 100%， 133%， and 166% of natural precipitation （G1， G2， G3， G4， G5）， were simulated by rainout shelters and manual water replenishment. Variation patterns of SOC， TN， TP contents across soil layers （0-10 cm，10-20 cm， and 20-30 cm） were analyzed under different precipitation levels. The results indicate that： （1） When precipitation increased （G4）， the SOC， TN， and TP contents， and soil C∶P and N∶P ratios in 10-20 cm and 20-30 cm soils were significantly lower than in 0-10 cm soils （P<0.05）. However， the TP content did not respond significantly to precipitation changes. （2） With the increasing of soil layer depth， the correlation between the contents and ratios of SOC， TN， and TP within soil followed the order of 20-30 cm>10-20 cm>0-10 cm； （3） The variation in the SOC， TN， and TP contents was the highest in the 20-30 cm layer， followed by the 10-20 cm， and was the lowest in 0-10 cm. The variation of soil TP content was the least for all the three soil layers. In conclusion， precipitation changes have a significant impact on the ecological stoichiometry of soil carbon， nitrogen， and phosphorus， and the variation of carbon， nitrogen， and phosphorus in deep soil is greater. Deep soil （20-30 cm） is more responsive to precipitation changes than surface soil （0-20 cm）， indicating that the ecological stoichiometry of desert steppe soils is more sensitive to precipitation in deeper layers.

In order to investigate the root-specific genes regulating root growth of alfalfa （Medicago sativa），transcriptome sequencing was performed to analyze differentially expressed genes （DEGs） and their functions between the aerial parts （stems and leaves） and root system of alfalfa cultivar Zhongmu No. 1. The results showed that compared to aerial parts，a total of 15258 DEGs were identified in root system，including 5095 up-regulated and 10163 down-regulated. The GO functional annotation demonstrated significant enrichment of these DEGs in cellular process，metabolic regulation，and biocatalytic activities. KEGG pathway enrichment analysis showed significant enrichment of these DEGs in pathways related to porphyrins and chlorophyll metabolism，photosynthesis-antenna protein synthesis，and carbon fixation in photosynthetic organisms. Six candidate up-regulated genes exhibiting significant differential expression were selected for real-time quantitative PCR validation. The results indicated high concordance between their expression patterns and transcriptome sequencing data.

Leymus chinensis is an important native forage grass species in China， yet its low seed setting rate greatly constrains large-scale production and utilization. To identify the key traits influencing seed setting and to evaluate their relative contributions， this study examined 100 Leymus chinensis germplasms collected from different geographic origins. Fifteen traits closely related to seed setting were measured， including seed number， spike weight， seed weight， floret number， spikelet number， spike length， number of spike knots， vegetative plant height， reproductive plant height， leaf length， leaf width， seed setting percentage， thousand seed weight， and the number of vegetative and reproductive branches. The results showed that there was substantial genetic variation among the germplasms， with coefficients of variation for the 15 traits ranging from 10.88% to 56.05%. Correlation analysis showed that spike weight， seed number， seed weight， and thousand seed weight were significantly and positively correlated with seed setting rate， indicating their central roles in reproductive success. Multiple regression and hierarchical partitioning analyses demonstrated that seed number had the greatest contribution to seed setting rate， accounting for 31.57% of variation. Principal component analysis indicated that the first five principal components collectively explained 78.126% of the total variance. Based on a comprehensive evaluation of these traits， ten germplasms （77， 23， 24， 37， 35， 20， 57， 10， 22， 7） were identified as superior germplasms with high reproductive potential and stable performance across multiple traits.

To investigate the mitigation effect of externally applied γ-aminobutyric acid （GABA） on the growth of alfalfa seedlings under drought stress， this study explored five new drought-resistant alfalfa lines （P1， P2， P3， P4， and P5） and five drought-sensitive materials （15354， 7657， 7470， 7740， and 15578）. With normal water supply as the control （CK）， drought stress was simulated using the previously screened stress intensity （-1.6 MPa PEG-6000）. Under this drought stress treatment， exogenous GABA was applied at concentrations of 0， 5， 10， and 15 mmol/L （designated as T1， T2， T3， and T4， respectively） to analyze their effects on the physiological characteristics of alfalfa seedlings. Results showed that external GABA application significantly increased superoxide dismutase， peroxidase， catalase， leaf relative water content， and root activity in alfalfa under drought stress， while the content of proline， soluble sugar， soluble protein， malondialdehyde， hydrogen peroxide， and the production rate of superoxide anion were decreased. Membership function analysis revealed the optimal alleviation of GABA on drought-stressed alfalfa under the T3 treatment， with significantly stronger mitigation effect on sensitive genotypes compared with drought-resistant lines. The results provide a theoretical basis for the rational application of GABA in drought-tolerant cultivation of alfalfa.

To clarify the pathogen species and their biological characteristics of oat spikelet rot in Guide county， Xining city， Qinghai province and Shandan county， Zhangye city， Gansu province， this study employed conventional tissue isolation methods to isolate pathogens， and used plate dilution method for single spore purification of isolates. According to Koch's postulates， combined with morphological and molecular biology techniques， 58 isolates were identified as Dactylobotrys graminicola. The results of biological characteristic analysis showed that the temperature range of mycelial growth of D. graminicola was 10-30 ℃， with the optimal temperature for growth and sporulation being 15 ℃. pH value had no significant effect on mycelial growth， and alkaline environment was more suitable for spore production. Complete darkness signicantly promoted the growth and sporulation of D. graminicola. D. graminicola could utilize various carbon and nitrogen sources， with inositol and ammonium chloride being the most suitable for the mycelial growth and sporulation， respectively. The results of this study provide a theoretical basis for the diagnosis and scientific prevention and control of oat spikelet rot.

The production performance and nutritional value of alfalfa remain pivotal concerns in the alfalfa industry development.This study evaluated 36 alfalfa accessions （31 cultivated varieties and 5 wild germplasms） using Grey Correlation Analysis.The results revealed significant differences （P<0.05） in both agronomic performance and forage quality parameters among the 36 alfalfa accessions. Hay yield of alfalfa ranged from 5380.74 to 12663.31 kg/hm²， with the high-yielding accession M10 demonstrating the highest fresh forage yield （54457.13 kg/hm²）. Notably， the medium-yielding accession M7 exhibited superior nutritional profiles with 19.03% of crude protein， while M11 had the highest relative feed value of 152.76. Accessions were selected by comprehensive analysis of grey correlation as three utilization categories：nine as superior， 25 as moderate， and 2 as inferior. Furthermore， wild alfalfa germplasm M31 and M32 exhibited superior comprehensive evaluation scores， demonstrating significant breeding potential for cultivar development. This research provides reference for alfalfa cultivar introduction in Urumqi County and supplies outstanding germplasm resources for development and utilization of native alfalfa in Xinjiang.

As a high-value cool-season grass species cultivated worldwide，perennial ryegrass （Lolium perenne L.） frequently faces various abiotic stresses. Fructans are the primary reserve carbohydrates in perennial ryegrass，which play a crucial role under abiotic stress conditions and significantly enhance stress tolerance. This article reviews research progress on fructan metabolism in perennial ryegrass in China and internationally，focusing on its biosynthesis and degradation pathways，as well as the regulatory mechanisms of certain biomolecules on fructan metabolism. In addition，metabolic changes and underlying mechanisms of fructans in perennial ryegrass were illustrated under various abiotic stresses including drought，low temperature，salinity，waterlogging，nitrogen deficiency，and mowing，with prospects on future research directions.

To investigate the effect of biochar coating on the drought resistance of Astragalus adsurgens， this experiment established four sand bed moisture levels （2%， 3%， 5%， and 10%， with 10% as control） and four biochar coating mass ratios （biochar∶seed at 1∶15， 1∶10， 1∶5， and 1∶3）. Germination tests conducted in the sand beds were aimed to identify apporiate drought stress simulation conditions and to determine the optimal biochar coating formulation. Effects of biochar coating on seedling emergence， seedling growth， and antioxidant enzyme activities under drought stress were also assessed. The results indicated showed that， under 2% sand bed moisture condition， which simulated drought conditions， the biochar coating treatment with at a 1∶10 mass ratio （biochar∶seed， denoted as BC1-10） significantly increased （P<0.05） seedling emergence rate， fresh weight， root length， seedling length， and antioxidant enzyme activities.

This bibliometric analysis investigated the research landscape of grassland-livestock balance， emphasizing publication trends， collaboration networks， and key research topics. Data were sourced from the Web of Science （WOS） Core Collection and the China National Knowledge Infrastructure （CNKI） databases. Using bibliometric analysis methods， VOSviewer 1.6.20 and CiteSpace 6.2.R6 software were employed to conduct a network analysis of countries， institutions， and author collaborations in relevant studies worldwide. Additionally， keywords co-occurrence， clustering， and burst analysis were performed to identify the research hotspots and development trends in the field. The results showed the following： （1） The annual publication output in grassland-livestock balance studies had been increasing both domestically and internationally， with the growth rate of international publications surpassing that of domestic ones； （2） China， the United States， and Germany were the leading countries in publication output， with research predominantly concentrated in universities and research institutions， notably the Chinese Academy of Sciences and Inner Mongolia Agricultural University； （3） Grassland and Turf and Agricultural and Forest Meteorology were the leading journals in terms of publication volume in this field， while veterinary medicine and animal science were the most prevalent subject categories domestically， and environmental science was the most popular internationally； （4） Current research primarily focuses on grassland ecological conservation and land use， the policies and influencing factors of grassland ecological compensation， and grassland vegetation and resources. The study suggests that future research in grassland-livestock balance should focus on regions such as Xinjiang， Qinghai， Inner Mongolia， and the Loess Plateau in China， emphasizing stocking rates， livestock numbers， family ranches， and ecological compensation policies for grassland conservation. Furthermore， exploring the mechanisms of grazing， rest grazing， and grazing prohibition on grassland-livestock balance management within grassland ecosystems is essential.

In order to investigate the effects of different mowing stubble heights and fertilization on the dominant species and soil trace element contents in meadow grassland， this research focused on Hulunbeier meadow steppe. Trace element contents of the dominant species Leymus chinensis and the surface soil （0～10 cm） were determined under the following treatment combinations：six mowing stubble heights （3， 6， 9， 12， 15 cm， and no mowing） and two fertilization levels （no fertilization and fertilization）. The results showed that mowing significantly increased （P<0.05） the total soil manganese （Mn） content. Fertilization significantly reduced （P<0.05） iron （Fe）， copper （Cu）， zinc （Zn）， molybdenum （Mo） contents of L. chinensis， whereas total Mn and Zn contents， available Zn and Mo contents， and effective coefficients of Mn， Zn， and Mo in soil were increased （P<0.05）. The interaction of mowing and fertilization did not affect the contents of Fe， Mn， Cu， Zn， Mo and boron （B） significantly. The highest total soil Mn content of 435.4 mg/kg was observed with the 12 cm stubble height under no fertilization treatment. When fertilization was applied， the highest Fe （191.6 mg/kg）， Mn （35.5 mg/kg）， Zn （10.8 mg/kg）， and B （4228.3 mg/kg） contents in L. chinensis were recorded， at the 6 cm stubble height， while available contents of Fe （126.7 mg/kg）， Mn （94.5 mg/kg）， Cu （1.4 mg/kg） and Mo （1.3 mg/kg） in soil reached maximum values with the 12 cm stubble height. Fertilizer application with 12 cm stubble height increased the effective coefficients of soil Mn， Zn， Mo and B by 0.1， 0.2， 0.4 and 1.9×10^-4， respectively. Compared with the treatment without fertilization， fertilization at a stubble height of 12 cm increased the contents of Fe， Mn， Cu and B of L. chinensis. This research can provide a practical reference for the establishing sustainable mowing system in meadow steppe.

In order to analyze the invasion mechanism of poisonous grass in alpine meadow of northwest Yunnan from the perspective of soil microbial diversity， this study focused on patches dominated by Ligularia dictyoneura， Euphorbia jolkinii， and Poa pratensis （control）， to explore the effects of poisonous grass invasion on soil microorganisms and their seasonal dynamics. The results revealed that the soil moisture content， organic carbon， total nitrogen， microbial biomass carbon and nitrogen， and the number and diversity of bacteria， fungi and actinomycetes in the patches of Euphorbia jolkinii and Ligularia dictyoneura were significantly higher than those in the patch of Poa pratensis， and Ligularia dictyoneura patch had significantly higher soil available nitrogen than Poa pratensis patch （P<0.05）. At the phylum and genus level， the composition of dominant bacteria in the three patches was similar， but the relative abundance of dominant bacteria in different patches and seasons was significantly different （P<0.05）. Compared with the patches of Poa pratensis， the Acidobacteria in the patches of Ligularia dictyoneura increased in autumn and winter， the Proteobacteria increased in summer and decreased in autumn， the Chloroflexi decreased in spring， summer and autumn， and the Ascomycota decreased in spring and winter and increased in summer， Basidiomycota decreased in spring and summer but increased inwinter. The Acidobacteria of the Euphorbia jolkinii patch decreased in summer and winter， the Proteobacteria increased in summer， autumn and winter， the Chloroflexi decreased in spring， summer and winter， the Ascomycota significantly decreased in spring and winter， and the Basidiomycota increased in spring and winter but decreased in summer （P<0.05）. The genus Archaeorhizomyces of Ligularia dictyoneura patch decreased in spring， while Hygrocybe increased in summer and winter. In the Euphorbia jolkinii patch， Archaeorhizomyces decreased in winter， while Hygrocybe increased in spring， summer and winter （P<0.05）. Correlation analysis revealed that soil pH， microbial biomass nitrogen and carbon were significantly correlated with fungi， while soil temperature and water content were significantly correlated with bacteria. The ecological functions of bacteria and fungi were mainly related to carbon cycle. In conclusion， the two invasion poisonous grass promote the spread and expansion of their populations by altering soil properties and microbial communities to form favorable environmental conditions for their growth.

Erosion control blanket technology is a practical and environmentally friendly ecological restoration method. This article systematically reviews nearly a century of global application history of erosion control blankets. The application of erosion control blanket demonstrates significant ecological benefits for soil and water conservation，soil improvement，and vegetation restoration. Advantages of erosion control blanket in ecological restoration are illustrated as wide material availability，high construction efficiency，ease of maintenance，low cost，and environmental friendliness. Regarding challenges in erosion control blanket application such as the lack of standardization in producing，weak long-term ecological data，poor performance on difficult sites，and outdated instillation techniques and equipment，this review proposes prospects to provide theoretical foundations for advancing the sustainable application of erosion control blankets in ecological restoration. Future research will focus on establishing standardized production systems，investigating medium-to-long-term ecological effects，and developing technological process and mechanical construction equipment.

This research aimed to explore the alleviating effects of exogenous abscisic acid （ABA） and hydrogen sulfide （H₂S） treatments on aluminum toxicity in perennial ryegrass.Growth and photosynthetic parameters of perennial ryegrass 'Mathilde' seedlings exposed to 500 mg/kg aluminum stress were measured under five treatments： CK，aluminum （Al），Al+0.4 mmol/L ABA，Al+1.2 mmol/L H₂S，and Al+0.4 mmol/L ABA+1.6 mmol/L H₂S. The results showed that the growth of ryegrass was significantly inhibited under aluminum stress，with 43.33% decrease of the root length compared with CK. Compared to aluminum treatment alone，exogenous ABA and H₂S significantly increased root length，plant height，aboveground and underground biomass of ryegrass. Specifically，the root lengths under the ABA treatment，H₂S treatment，and ABA+H₂S treatment were increased by 63.92%，58.83%，and 71.37%，respectively，and the plant heights were increased by 18.86%，27.43%，and 33.71%，respectively. Individual or combined application of exogenous ABA and H₂S significantly increased the contents of chlorophyll a，chlorophyll b，and total chlorophyll. In addition，the intercellular CO₂ concentration decreased significantly，while the net photosynthetic rate，stomatal conductance，and transpiration rate increased significantly. Among them，after the combined addition of ABA and H₂S，the chlorophyll b，total chlorophyll content and net photosynthetic rate increased the most. In contrast，individual application of ABA induced transpiration rate even exceeded that of the CK. Exogenous ABA and H₂S were considered to mitigate aluminum-induced growth inhibition in perennial ryegrass，to enhance leaf photosynthetic pigments accumulation，to reduce photosystem damage，and to improve photosynthesis. Comprehensive evaluation revealed that the aluminum toxicity mitigation effects followed the order of ABA+H₂S>ABA>H₂S.

In this research， effects of three light modes of LED red， blue， and green light spectrum at 23.328 mol/（m²·d） DLI （conventional light with 18 h/6 h， red∶blue∶green=280∶70∶10； continuous light with 24 h/0 h， red∶blue∶green=210∶52.5∶7.5； and alternating light with three light spectra： 24 h/0 h， red∶blue∶green=525∶15； red-green light∶blue light=435∶105； green and blue light∶red light=120∶420） on yield quality， physiological activity， and nitrogen metabolism were determined in an controlled environment plant factory with artificial light. The results demonstrated the adaptability of alfalfa to continuous light. Compared with conventional lighting， healthy morphology and maintained yield were observed in alfalfa under continuous lighting， along with increased soluble sugar and starch content. However， decreases occurred in photosynthetic pigment content， stomatal conductance， and Fv/Fm， without excessive accumulating of H₂O₂ and malondialdehyde. Further data showed that the alternation of red/blue-green light promoted leaf expansion， the alternation of red/green-blue light promoted stem elongation， and the alternation of green/blue-red light shortened the flowering time. In terms of nitrogen metabolism， nitrate nitrogen content was significantly reduced under continuous and green/blue-red light alternation， while ammonium nitrogen content was significantly increased under red/green-blue light alternation. Activity of nitrate reductase was significantly reduced under red/blue-green light alternation， while red/green-blue light alternation significantly reduced nitrite reductase activity. The activity of nitrogen metabolism enzymes was inhibited by continuous and alternating lighting， whereas the content of soluble protein， free amino acids， and crude protein in alfalfa were increased. In summary， continuous lighting and alternating lighting patterns are suitable for the production of alfalfa in plant factory with artificial light.

Overexploitation and improper management of grasslands have intensified the conflict between grassland resources and livestock production， underscoring the necessity of implementing grassland-livestock balance management to alleviate these tensions. This study analyzed the evolution and research trends in grassland-livestock balance using data retrieved from the China National Knowledge Infrastructure （CNKI） and visualized with CiteSpace software. Furthermore， the study identified current hotspots and potential future directions within this field. The results showed three distinct phases in the research output from 1986 to 2023： a slow growth phase （1986-2002）， a fluctuating growth phase （2003-2012）， and a stable growth phase （2013-2023）. The total number of publications exhibited an increasing trend， and a cluster of influential research institutions emerged during the study period. However， inter-regional collaboration among authors and institutions was limited， indicating a weak overall correlation. Key word co-occurrence and cluster analysis identified three primary research hotspots： balanced development of grassland ecological animal husbandry， accounting and monitoring systems for grassland-livestock balance， and policy incentives and development strategies. Key word burst analysis indicated that since 2020， research has increasingly focused on themes such as grazing prohibition， family ranches， and grassland ecology. Therefore， it is suggested that future research should emphasize the management and monitoring system for grassland-livestock balance， standardizing the calculation methodologies for dynamic carrying capacity， and addressing existing challenges in grassland-livestock balance incentive policies， to promote sustainable grassland utilization within the framework of ecological civilization construction.

The D27 （DWARF27） gene encodes an iron-containing β-carotene isomerase essential for strigolactone biosynthesis. In this study， the TpD27 gene was cloned from Trifolium pratense ‘Minshan’ using RT-PCR. Bioinformatics analysis revealed that the full-length coding sequence of TpD27 was 792 bp， encoding a 264-amino acid protein with a predicted molecular weight of 29.71 kDa， an isoelectric point of 8.76， and an instability index of 51.30， indicating that it was an unstable protein. Subcellular localization prediction suggested that TpD27 may be localized in the chloroplasts. The secondary structure of TpD27 was mainly composed of α-helix （33.71%） and random coil （55.68%）， consistent with its predicted tertiary structure. Phylogenetic analysis showed that TpD27 clusters closely with MtD27 from Medicago truncatula， indicating a close evolutionary relationship between the two species. Spatiotemporal expression profiling revealed tissue-specific expression of TpD27， with the highest transcript levels in flowers and the lowest in roots. Under abiotic stress conditions， TpD27 expression was significantly downregulated in response to cadmium， salt， and drought treatments. Under low-temperature stress， its expression followed a dynamic pattern： initial downregulation， subsequent upregulation， and eventual decline. The recombinant expression vector pCAMBIA2300-TpD27 was successfully introduced into wild-type Arabidopsis thaliana via Agrobacterium-mediated floral-dip transformation. Phenotypic analysis demonstrated that the transgenic Arabidopsis thaliana exhibited a significantly reduced number of branches compared to the wild-type plants.

Fertilization is a key strategy for restoring degraded grasslands. To identify suitable nitrogen （N） and phosphorus （P） fertilization gradients for enhancing the productivity and soil characteristics of degraded alpine meadows， a lightly degraded alpine meadow in Dangxiong County， Xizang Autonomous Region， was selected for study. A two-factor randomized block design was employed， with four nitrogen levels （N0：0 kg N/hm²， N1：60 kg N/hm²， N2：90 kg N/hm²， N3：120 kg N/hm²） and four phosphorus levels （P0：0 kg P₂O₅/hm²， P1：30 kg P₂O₅/hm²， P2：60 kg P₂O₅/hm²， P3：90 kg P₂O₅/hm²）， resulting in 16 N-P treatments combinations， with N0P0 treatment serving as the control （CK）. Grassland productivity and soil characteristics were evaluated to determine the optimal N-P combinations. The results showed that the combined application of nitrogen and phosphorus fertilizers significantly enhanced aboveground biomass compared with the control， with the N2P2 and N2P3 treatments increasing biomass by 136.9% and 111.9%， respectively （P<0.05）. The combined application also improved soil organic carbon content， particularly in the 0-10 cm soil layer， where the N2P1 and N2P3 treatments reached 15.67 g/kg and 15.26 g/kg， respectively. Available phosphorus content was highest under N2P3 treatment in both 0-10 cm and 10-20 cm soil layers， while total nitrogen content was greatest under N3P1 treatment. Grey correlation analysis of aboveground biomass and soil characteristics （0-10 cm） indicated that N2P3 treatment provided the most favorable comprehensive improvement in productivity and soil nutrient status， followed by N3P3 treatment. Therefore， the combination of 90-120 kg/hm² nitrogen fertilizer with 90 kg/hm² phosphorus fertilizer is recommended as the optimal strategy for the restoration of degraded alpine meadows in Dangxiong County， Xizang Autonomous Region.

This study aimed to explore the impacts of salt stress on the photosynthetic characteristics and sugar metabolism of Astragalus cicer seedlings. A. cicer cultivar ‘Gan Green No. 2’ was treated by 120 mmol/L NaCl solution as salt stress simulation. Sampling was conducted at 0， 1， 3， 5， 7， 14， and 21 days after stress applied for relevant indices measurement. The results indicated that salt stress induced stomatal closure in the leaves of A. cicer seedlings resulting in reduced stomatal conductance reduction and impairment of the photosynthetic system. Simultaneously， the chlorophyll content， net photosynthesis rate， transpiration rate， actual photochemical efficiency， apparent photosynthetic electron transport rate （ETR）， and photochemical quenching coefficient were significantly decreased. However， the contents of sucrose， fructose， and glucose exhibited trends of increasing initially followed by declining. Moreover， the intercellular CO₂ concentration， non-photochemical quenching coefficient （NPQ）， starch content， sucrose synthase （SS） activity， and activities of soluble acid invertase （SAI） and neutral invertase （NI） increased and eventually stabilized with treatment time prolonged. In contrast， the sucrose phosphate synthase activity （SPS） gradually exhibited a decreasing trend. Correlation analysis demonstrated that soluble sugars content were closely related to photosynthetic parameters， suggesting that sugars may play a crucial role in regulating of photosynthesis and plant light use efficiency. Starch content was positively correlated with NPQ， indicating that starch may be involved in regulating photoprotection and energy dissipation. In conclusion， salt stress tolerance of A. cicer seedlings can be enhanced by regulating sugar metabolism-related enzyme activities and photosynthetic system， leading to increased soluble sugar and NPQ levels. The findings of this study provide valuable insights into the growth and physiological mechanisms of A. cicer in saline-alkaline soils.

Grazing is a primary utilization of grassland ecosystems， where livestock behaviors， specifically feeding， trampling， and excrement deposition， directly or indirectly alter soil physicochemical and biological properties. These alternations， in turn， differentially affect biogeochemical processes within the grassland ecosystem. However， the mechanisms by which these behaviors influence soil greenhouse gas （GHG） emissions remain poorly understood. To address this knowledge gap， this study systematically explored the emission mechanism and key influencing factors of carbon dioxide （CO₂）， methane （CH₄）， and nitrous oxide （N₂O） in grassland soil by analyzing the interactions between major grazing behaviors and soil environmental conditions. The results showed that feeding behavior can alter vegetation biomass and regulate vegetation community structure， thereby modifying exogenous carbon inputs to influencing soil CO₂ emissions. Trampling behavior impacts soil physical structure and microenvironmental conditions， which in turn affect soil aeration and microbial activity， leading to variable effects on soil respiration and associated CH₄ and CO₂ emissions. These effects are closely dependent on grassland type and trampling intensity. In contrast， dung and urine deposition increase nitrogen input to the soil and enhance N₂O emissions， primarily by altering soil chemical properties and microbial dynamics. The characteristics of the excreta， grassland type， and environmental conditions all play important roles in regulating nutrient availability and GHG emission in pastoral systems. These findings elucidate the distinct processes and potential mechanisms through which livestock behaviors affect soil GHG emissions in grassland and provide a theoretical basis for optimizing grazing management to mitigate emissions in pastoral ecosystems.

To investigate the genetic variation characteristics and agronomic potential of the polycotyledon trait in alfalfa （Medicago sativa L.），this study evaluated the phenotypic diversity of alfalfa cotyledonous mutations under field cultivation. Eleven agronomic quantitative traits were assessed using the Kruskal-Wallis non-parametric test，mean analysis method，and the entropy-weight TOPSIS method. The results showed that： （1） The polycotyledonous mutation rate in the test population was 1.44%，with 29 phenotypic variation patterns were identified；（2） the B8 type （tricotyledon-one unifoliolate true leaf-normal main stem-erect branches） exhibited the highest mutation rate （41.28%），followed by the B2 type （dicotyledon-two unifoliolate true leaves-normal main stem-erect branches） at 8.74%；（3） Mean analysis indicated that differences among variant types were mainly associated with branch number and plant height；（4） The entropy-weight TOPSIS evaluation ranked the B2 type highest （score： 0.8389），followed by the B8 type （0.6297），whereas the B12 type （tricotyledon-one unifoliolate true leaf-clustered branch） scored lowest. This study provides the first systematically characterization of phenotypic diversity and agronomic polycotyledonous alfalfa variants and offers novel mutant germplasm resources for breeding innovation.

In order to clarify the effect of grazing utilization on the important value of dominant population and species diversity in the desert steppe after spring rest grazing， this study was conducted on the Stipa breviflora grassland in Xilin Gol League of Inner Mongolia. Results revealed that the species diversity of plant communities was reduced following the order of CK （no grazing）， SA1 （spring rest grazing+summer heavy grazing+autumn suitable grazing） and SA2 （spring rest grazing+summer suitable grazing+autumn heavy grazing）. Grazing increased the correlation between the important value of different dominant species and the species diversity of plant communities. Although the grazing utilization methods of SA1 and SA2 have similar influence processes， the overall correlation between the important value of dominant populations and species diversity indicated that the effect of dominant populations and species diversity on plant communities under SA1 was greater than SA2. Therefore， the grazing management of spring rest grazing+summer heavy grazing+autumn suitable grazing can maintain the structure and function of grassland plant community through a strong correlation between the important value of dominant populations and species diversity.

To evaluate the differences in drought adaptability and post-drought recovery among various bermudagrass （Cynodon dactylon） germplasms， this study assessed seven physiological indices in 18 germplasms under drought stress and subsequent rewatering， using a natural drought simulation method. The study aimed to clarify the variations in drought resistance and recovery capacity， identify superior germplasm， and determine key indicators through grey correlation analysis. The results showed that by the 12th day of drought， the contents of leaf chlorophyll a， chlorophyll b， total chlorophyll， and relative water content decreased significantly， whereas relative electrical conductivity， malondialdehyde， and proline contents increased significantly. Membership function analysis revealed that the D value for drought stress ranged from 0.056 to 0.725， while the D value for recovery after drought ranged from 0.239 to 0.828. Under drought stress conditions， germplasms C136， C75， and C92 showed higher D values （0.725、0.670、0.537， respectively）. In terms of post-drought recovery， C121， C92 and C136 had the highest D values （0.828、0.767、0.721， respectively）. Among the germplasms， the drought resistance and post-drought recovery capabilities of C136， C92， C100 and C22 were all higher than those of the four control variety. Grey correlation analysis indicated that chlorophyll a content was highly correlated with drought resistance， while leaf relative water content was highly correlated with post-drought recovery ability. These parameters can serve as important indicators for evaluating drought tolerance in bermudagrass.

In this study， strain TL-3 was isolated from naturally infected Cenchrus longispinus， and identified as Alternaria alternata by morphological and molecular biology. The herbicidal activity of TL-3 was determined by paper dish method and indoor biocontrol test. The results showed that the inhibition rate of TL-3 fermentation broth on the growth of roots and buds of C. longispinus was 67.65%， 59.65%， respectively. The incidence rate of stem and leaf diseases was as high as 63.89%. However， the inhibition rate of TL-3 on the germination of C. longispinus seeds was relatively weak， with an inhibition rate of only 10.02%. The herbicidal activity of TL-3 fermentation broth on six kinds of common farmland weeds showed that it had obvious pathogenic effect on Chenopodium album， Echinochloa crusgalli， Amaranthus retroflexus and Chloris virgata. The disease incidence was 85.65%， 84.94%， 50.91%， 41.51%， and the disease index was 85.93， 87.04， 44.35 and 45.15， respectively. The incidence and disease index of C. album and E. crusgalli were significantly higher than those of other weeds （P<0.05）. The disease incidence of Setaria viridis and Digitaria sanguinalis were 23.28% and 29.25%， respectively， and the disease index was 29.44， and 27.98， respectively. The results showed that the disease incidence of Medicago sativa and Melilotus officinalis was 45.07% and 40.88%， respectively， and the disease index was 40.26 and 44.39， respectively. The disease incidence of M. sativa was significantly higher than that of other forage and crops （P<0.05）， and the disease index of M. officinalis was significantly higher than that of other forage and crops （P<0.05）. The incidence rates of maize， wheat， oats， and Medicago ruthenica were 26.32%， 24.32%， 29.07%， and 28.90%， respectively， and the incidence rates of Glycine max， Solanum lycopersicum， Brassica oleracea， and Brassica pekinensis were 11.11%， 10.71%， 14.92%， and 9.21%， respectively， Solanum melongena， Capsicum annuum， Elymus dahuricus， Leymus chinensis， Cucumis sativus and Spinacia oleracea showed no obvious symptoms compared with the control group. The results indicated that strain TL-3 was safe. In summary， strain TL-3 had a significant pathogenic effect on C. longispinus and can be safely used in artificial grasslands/or wastelands mainly composed of L. chinensis. It is a new solution for the control of C. longispinus and has the potential to be developed as a bioherbicide.