Plant-endophyte symbioses play an important role in alleviating abiotic and biotic stresses to plants. Under drought and salt stresses, endophytic bacteria can enhance the resistance of plant to the stresses by regulating plant photosynthesis, concentration of hormones, content of osmoregulatory substances, activity of antioxidant enzyme, and expression of genes to ensure a normal growth and development of plant. In recent years, plant growth-promoting bacteria (PGPB) inoculants have also been widely studied and applied. In this paper, we reviewed the diversity of endophytic bacteria, the regulation of plant genes by plant symbiotic endophytes and PGPB under drought and salt stresses, and provided a reference for the in-depth study of the molecular mechanism of endophytic bacteria to improve the tolerance of plant to drought and salt stresses.

To explore the effects of warming on the plant communities and soil physicochemical properties of subalpine meadows in the growing season in Wutai Mountain,a warming experiment using the open-top chambers (OTCs) was set up. Redundancy analysis (RDA) was used to reveal the relationship between plant communities and soil properties. The results showed that after three years of warming,species richness (SR) increased significantly ( P<0.05). The importance value (IV) of Kobresia humilis was the highest (0.31) in the controlled plots,but IV of Polygonum viviparum was the highest (0.15) in the warmed plots. The OTCs significantly ( P<0.05) increased the above-ground biomass (AGB) by~2.83 times,but significantly ( P<0.05) decreased the below-ground biomass (BGB) by 35.96%. Under warming treatment,soil moisture (SM),soil organic carbon (SOC),and total nitrogen (TN) significantly ( P<0.05) decreased by 24.58%,11.86%,and 19.80%,respectively. Under the warming treatment,SM and TN had significantly positive correlation with AGB ( P<0.01);there was a significantly positive correlation between pH and BGB ( P<0.05). This study demonstrated that the community structure changed and the surface soil tended to become arid and barren under warming conditions for the subalpine meadows in Wutai Mountain.

In order to reveal the impacts of future climate change on grassland ecosystems and their responses,this study assessed the spatiotemporal dynamics of global grassland ecosystems and their net primary productivity (NPP) in 2020-2100 based on four future climate scenarios (including SSP126,SSP245,SSP370,and SSP585) using an improved comprehensive sequential classification system (CSCS) and a segmentation model. Results showed that the global mean annual temperature (MAT) and mean annual precipitation (MAP) would exhibit an overall upward trend in all four climate scenarios. In the SSP126 and SSP245 scenarios,the global grassland area was expected to decrease by 1.94 million km ² and 1.78 million km ² by 2090 s,respectively,mainly due to the reduction of tundra and alpine steppe. In contrast,the global grassland area was expected to increase by 0.68 and 1.37 million km ² by 2090 s in the SSP370 and SSP585 scenarios,respectively,which was mainly caused by the increase in the area of the tropical savanna. Global grassland NPP showed an increasing trend in SSP126,SSP245,SSP370,and SSP585 scenarios,expecting to increase by 0.25,1.96,5.78,and 7.52 Pg DW by 2090 s,respectively. Tropical savanna would contribute the most. In the context of global warming and humidification,tropical savanna and tundra and alpine steppe grasslands would be more vulnerable to future climate change.

Grasslands are important natural resource and ecological barrier in our country. Grassland ecological restoration is an important part of China's ecological conservation, as well as an important approach to enhance the ecosystem service function and carbon sequestration potential of grassland. Extensive studies have been conducted on degraded grassland, and many effective restoration practices have been proposed. However, there is a lack of comprehensive and target-oriented summaries of these restoration practices. This study conducted a systematic review of domestic and international research on grassland ecological restoration based on bibliometric research approach. We summarized the three stages of grassland ecological restoration in China and explored a regional-classified-hierarchical ecological restoration model for grasslands under different regions, different degradation types and different degradation degrees. Additionally, we provided relevant suggestions for the future development of grassland ecological restoration in China, and aimed to provide scientific basis for the ecological restoration and sustainable management of grasslands in our country.

Epichloë grass endophyte is a group of fungi that finish most their life cycle in the intercellular space of the host grasses,but do not cause obvious external symptoms on the hosts. As an important agricultural microbial resource,it can promote the growth of hosts and improve the host's resistance to adversity. In addition, some alkaloids produced by the symbionts formed by some endophytic fungi and their host,can cause herbivorous livestock be poisoned and affect the healthy development of grassland animal husbandry. This dual characteristic of grass endophyte has become a research hotspot in the field of international grass industry for the past 30 years. In this study,the nomenclature history,classification status of teleomorph and anamorph grass endophyte,classification methods and significance of grass Epichloë endophyte were reviewed. Moreover,the resources and the distribution of grass endophytic fungi found in China and the research progress about grass endophytic fungi in stress resistance breeding were also summarized. The review was prospected to provide scientific basis for mining and utilizing beneficial grass endophytic fungi resources,cultivating new varieties of excellent plants,developing modern grassland animal husbandry and taking the ecological environment construction.

As one of the important industries in the field of agriculture,the grass seed industry is playing an increasingly important role in improving the efficiency of farming,increasing the income of farmers and herdsmen,and promoting high-quality economic and social development. The collection,preservation,identification,evaluation and innovative utilization of germplasm resources and the breeding of new varieties (lines) have become hot topics in the current research of grass seed industry. This paper mainly summarized and prospected the genetic diversity of grass germplasm resources from four aspects:morphology,biochemistry,cytology and molecular level,aiming to provide reference for the creation and breeding utilization of grass germplasm resources.

In order to investigate the effects of grazing and nitrogen addition on plant-soil carbon and nitrogen cycling in Inner Mongolian desert grasslands, nitrogen addition treatments were carried out in forbidden (UG, 0 sheep unit·hm ^-2) and heavily grazed (HG, 1.74 sheep unit·hm ^-2) sample plots at the following levels:control (CK, 0 g·m ^-2·a ^-1), low nitrogen (LN, 5 g·m ^-2·a ^-1), medium nitrogen (MN, 10 g·m ^-2·a ^-1) and high nitrogen (HN, 20 g·m ^-2·a ^-1), total nitrogen (TN), stable carbon isotopes (δ ¹³C), stable nitrogen isotopes (δ ¹⁵N), soil organic carbon (SOC) and available nitrogen (AN) were measured and analyzed, and the results showed that:Grazing significantly increased the content of TC, TN and AN in the soil ( P<0.05);Grazing significantly reduced the values of δ ¹³C and δ ¹⁵N of the leaves of Stipa breviflora needlegrass ( P<0.05);grazing significantly reduced the δ ¹³C and δ ¹⁵N values of Stipa breviflora leaves ( P<0.05). To a certain extent, both grazing and nitrogen addition accelerated the nutrient cycling of fagus sylvatica and soil, and at the same time, nitrogen addition had a certain effect on nitrogen uptake and fractionation of fagus sylvatica, which is important for the recovery of degraded grassland.

Grassland is the largest terrestrial ecosystem in China, serving as the cornerstone for safeguarding national ecological security, fostering ethnic unity, and propelling regional economic-social development. In the new era, the ecological conservation of grassland and the green and high-quality development of grass industry are confronting with both new opportunities and challenges. This article delves into several aspects, including grassland technological innovation, the utilization of “the third national land resource survey” data in grassland management, the establishment of germplasm resource breeding and multiplication base of native grass, and the cultivation of local advanced talents in the western region. The aim is to provide references for cultivating new quality productive forces in the grass industry and promoting its high-quality transformation and development under the new circumstances.

Eight alfalfa varieties( Medicago sativa L.)introduced at home and abroad were used as test materials to compare and study the leaf characteristics,yield traits,and photosynthetic physiological properties of different varieties. Correlation analysis and throughput analysis were used to explore their correlation with yield and provide a basis for the screening of high-yielding alfalfa germplasm. The results showed that the variation of single plant dry weight of alfalfa varieties for the test was 0.88~1.21 g. The correlation between various traits and single plant dry weight was ranked in order of magnitude as follows:single leaf dry weight > specific leaf weight > transpiration rate > number of leaves per plant > leaf shape index,with single plant leaf dry weight being the most prominent leaf characteristic indicator. The degree of influence on the dry weight of a single plant was as follows in descending order:specific leaf weight > stomatal conductance > soluble protein > plant height > sucrose > soluble sugar > total chlorophyll,of which specific leaf weight was the main determinant of the dry weight of a single plant. In summary,the most important indicators for screening high-yield alfalfa germplasm were single plant dry weight and specific leaf weight. Among the 8 alfalfa varieties,‘Gannong No.9’,‘WL319HQ’ and ‘SG501’ have relatively high single-plant dry weight,single-plant leaf dry weight,and specific leaf weight,which can be studied and utilized as high-yielding germplasm in breeding work.

Grassland is a crucial terrestrial ecosystem, and phosphorus availability can limit its plant productivity. Phosphorus is obtained by plants primarily from soil, and its transformation and availability is influenced by various factors. Grazing, a common practice in grasslands, can impact soil phosphorus conversion by altering soil physical and chemical properties, soil microorganisms, and plant root exudates. However, with changing global precipitation patterns, how grazing and land utilization affect soil phosphorus conversion and availability has gained attention among researchers.This paper provided a review of the effects of precipitation and grazing on soil phosphorus conversion in grasslands, focusing on factors such as soil moisture content, pH, soil phosphatase activity, and root exudates, additionally, the responses of soil phosphorus conversion to grazing with different precipitation levels. In the future, studying the effects of precipitation changes and grazing utilization on soil phosphorus transformation in grasslands requires to consider multiple perspectives, such as natural factors and human disturbances, biological and abiotic interactions, and long-term and large-scale effects. This holistic approach will enhance our understanding of the soil phosphorus cycle in grasslands and provide valuable insights for grassland restoration in the face of changing precipitation patterns.

Forage is an important material basis for the benign development of herbivorous animal husbandry,and forage industry is an important part of its development,which plays an important role in optimizing agricultural structure. At present,Hulunbuir forage industry resources (27.96 million tons annual output) include mainly three plates:natural forage,artificial forage and straw forage,accounting for 32.8% of the effective utilization of resources. However,focusing on the industrial level,there are still many problems:no quantitative standard for classification and grading,loss and waste of grass resources,information asymmetry between market supply and demand,scientific and technological low level of forage industry,difficult formation of industrial chain,etc. At the same time,it is also facing with problems in resources,technology,policy and so on. This paper combed the present situation of the production of natural forage,artificial forage and straw forage industry in Hulunbuir,and comprehensively analyzed the problems existing in the development of Hulunbuir forage industry. Measures and suggestions were proposed,including optimized forage industry,strengthened forage storage construction to reduce waste and loss,diversified grass product technology research and development,artificial grassland construction to reduce grassland bearing pressure,supporting forage industry leading enterprises,and others,to provide reference for the high-quality development of Hulunbuir forage industry.

Early and rapid identification of F1 hybrid progeny and acquisition of true hybrids are of great significance to the breeding and genetic research of Trifolium repens superior strains. Six phenotypic traits of 2 Trifolium repens parent materials and 55 F1 hybrids were mapped by clustering heat map,and 3 pairs of specific SSR primers were selected to identify the authenticity of F1 hybrids. The results showed that the 57 materials in the cluster heat map could be divided into 2 classes according to the phenotypic characters of their parents. A total of 281 distinct bands and 137 polymorphic bands were obtained by amplification with 19 pairs of selected primers. The polymorphic sites accounted for 48.41%. The PIC of each SSR site ranged from 18.49% to 43.58%,with an average value of 34.73%. A total of 53 true-hybrids were identified by three pairs of specific primers,and the true-hybrid ratio was 96.36%,which was basically consistent with the results of UPGMA cluster analysis. The 19 pairs of SSR molecular marker primers have high polymorphism,which can be directly used for genetic diversity analysis of Trifolium repens and hybrid identification and other related studies. The identified F1 generation true hybrids of Trifolium repens can lay a foundation for subsequent breeding work.

Drought is one of the important factors that limit the growth of alfalfa. MYB transcription factor widely involves in the regulation of plant growth and development and abiotic stress. In this study,cloning and bioinformatics analysis of alfalfa MsMYB58 gene were performed to analyze the function of MsMYB58 in response to drought stress. The results showed that the length of MsMYB58 open reading frame was 1 002 bp,encoding a protein containing 333 amino acids,and the molecular weight was 37.80 kDa,which was a representative member of the R2R3-MYB family,localizing in the nucleus,cell wall,and membrane. The tissue-specific expression of MsMYB58 was mainly in stems and the least in roots. The expression levels of MsMYB58 showed different trends in abscisic acid (ABA),salt (NaCl) and natural drought treatment. Under drought stress,overexpressing MsMYB58 in tobacco showed a significant increase in catalase,peroxidase and superoxide dismutase activities and proline content,a significant decrease in malondialdehyde content,a significant increase in chlorophyll fluorescence parameters Phi2 and F _v/F _m,and a significant decrease in NPQt. In this study,the function of alfalfa MsMYB58 in response to drought stress was investigated and provided a theoretical basis for further excavation of drought-responsive functional genes in alfalfa.

Data monetization refers to the allocation of data property rights and the circulation of data elements in the form of transactions,resulting in sustainable returns. Data monetization management is of great significance in the field of forestry and grassland,as it can effectively enhance the value and utilization efficiency of forestry and grassland data,and promote innovative development in forestry and grassland work. This paper aimed to explore the architecture of data monetization management in the forestry and grassland sector,and conduct a case study on data asset management and operation in China. Under the background of data elementization,the forestry and grassland data had not yet formed a complete industrial chain,and its potential value could not be fully released and realized. By researching and establishing a data center or similar institution that dominates the national forest and grass industry,undertakes data regulatory responsibilities,authorizes the management,operation,and coordination of forest and grass data assets,and establishes cooperative relationships with relevant parties such as data providers,data developers,and data product demanders,It would have broad prospects for effectively promoting the production,distribution,circulation,and trading of forest and grass data.

In order to improve Agrobacterium tumefaciens-mediated genetic transformation efficiency of alfalfa ( Medicago sativa L.),we used alfalfa variety 'Zhongmu No.1' as plant material. The genetic transformation system of alfalfa mediated by agrobacterium was optimized by selecting the highly regeneration plant,using young leaves as explants,adjusting the hormone ratio in the medium,adding glutamine,and giving a cold treatment during agrobacterium infection. The results showed that the transient transformation efficiency of 'Zhongmu No.1' increased from 32% to 92% and the stable transformation efficiency increased to 31% by adding 150 μmol·L ^-1 acetosyringone to the bacterial suspensions solution,and using 300 μmol·L ^-1 glutamine during infection. The genetic transformation system of alfalfa reported in this paper provides technical support for efficient genetic improvement and gene functional study of alfalfa.

To explore the mechanism of waterlogging tolerance in alpine wetland plants,the morphological,physiological,and biochemical indexes of 5 plants,including Hippuris vulgaris were determined after 40 days of waterlogging. The evaluation system of waterlogging stress adaptability was constructed by PCA analysis,correlation analysis,and membership function method using waterlogging tolerance coefficient. The results showed that the activity of antioxidant enzymes increased by 1~4 times under waterlogging stress to resist waterlogging stress and adapt to a waterlogging environment. The responses of malondialdehyde content,antioxidant enzyme activity,and osmoregulatory substances to waterlogging stress were different in the shoot and root parts of different plants. Through PCA analysis and correlation analysis,plant height,photosynthetic pigment content,soluble sugar content,soluble protein content,peroxidase activity,and superoxide dismutase activity in the shoot can be used as the main evaluation indexes for the adaptability screening of plants under waterlogging stress in alpine wetland. According to the weighted and membership function analysis of the comprehensive indexes (PC1~4),the order of adaptability to waterlogging stress of the 5 alpine wetland plants was Hippuris vulgaris> Halerpestes tricuspis> Poa araratica subsp. Psilolepis> Trichophorum distigmaticum> Pedicularis chinensis.

To explore the effects of different mixed sowing patterns on forage yield and nutritional value, 11 mixed sowing patterns were studied in this experiment by controlling the mixed sowing proportion and the mixed forage species, namely, 4 mixed sowing patterns of legume forage:mixed sowing ratios of Medicago varia + Onobrychis viciaefolia + Lotus corniculatus were 1:1:1, 1:1:2, 1:2:1, 2:1:1 (Z1H1B1, Z1H1B2, Z1H2B1, Z2H1B1), 4 mixed sowing patterns of gramineous forage:mixed sowing ratios of Elymus dahuricus + Bromus inermis + Agropyron cristatum were 1:1:1, 1:1:2, 1:2:1, 2:1:1 (W1P1B1, W1P1B2, W1P2B1, W2P1B1), and 3 mixed sowing patterns of legume and gramineous:mixed sowing ratios of Medicago varia + Onobrychis viciaefolia + Lotus corniculatus + Elymus dahuricus + Bromus inermis + Agropyron cristatum were 1:3, 1:1, 3:1 (L25G75, L50G50, L75G25). The results showed that the plant height, density and dry matter yield of the six forage mixed sowing patterns were lower than those of the three leguminous forage mixed sowing patterns and the three gramineous forage mixed sowing patterns( P<0.05), but the crude protein content and relative feeding value of the forage were lower than those of the three leguminous forage mixed sowing patterns( P<0.05), and higher than those of the three gramineous forage mixed sowing patterns( P<0.05). The results showed that 1:1 mixed sowing ratio was more conducive to the accumulation of total dry matter in six mixed sowing patterns.

In order to investigate the effects of abandonment years on cropland soil, a field survey was conducted in August,the peak season of plant growth. Soil samples were collected from unabandoned cropland (CK) and croplands with different abandoned years (7 years,7a;15 years,15a;30 years,30a). Soil physicochemical properties,soil moisture and nutrients were analyzed and calculated. The results showed that abandonment had a significant improvement on soil bulk density,and significantly decreased soil porosity and pH. Compared with unabandoned cropland,abandonment significantly elevated the contents of soil organic carbon (SOC),total nitrogen (TN) and total phosphorus (TP). Consequently,long-term abandonment had a significant improvement effect on soil nutrient status. Soil water content and soil nutrient indicators exhibited a significant positive correlation at different abandoned years. The results showed that less evapotranspiration reduced soil water loss and accumulated soil nutrients under long-term abandonment. Further,there were significant positive correlations between soil water content and at least one variable related to soil nutrients. Therefore,long-term abandonment had positive effects on soil nutrients content,which might be due to the fact that less evapotranspiration reduced the loss of soil water content,and further promoted the accumulation of soil nutrients. This study can provide theoretical support for rational planning of abandoned cropland in the agro-pastoral ecotone in Bashang of Hebei Province.

Desert steppe is a fragile ecosystem. Exploring the response of desert steppe to long-term climate change and human interference provides a more reliable theoretical reference for the research on the adaptability of fragile ecosystems. We reviewed key findings of research related to the desert steppe dominated by Stipa breviflora over the past 20 years. We summarized the response and adaptation characteristics of the desert steppe of Stipa breviflora to different grazing utilization and different grazing intensities from the perspectives of plant individuals,populations,communities,ecosystems and soil physicochemical properties. These results would effectively save time for subsequent researchers to consult and identify areas of weak knowledge. Several important topics and key scientific issues,which urgently need to be addressed in the following future,have proposed.

This study was conducted to evaluate the effects of different cover cropping strategies on the soil's physical and chemical properties,as well as the bacterial community structure in organic kiwifruit ( Actinidia chinensis) orchards in the Guanzhong Area. This experiment was conducted in 2021 at the Yangling Baiheng Organic Kiwi Orchard in Shaanxi Province. Three artificial cover cropping measures were tested: Lolium multiflorum+ Astragalus sinicus, Lolium multiflorum+ Glycine max, Lolium multiflorum+ Vicia villosa,with natural grass used as a control. The chemical properties and bacterial community structure of the soil in the topsoil(0~20 cm) were determined. The results showed that the organic matter of artificial grass increased by 8.8%~11.9% compared to the control,with the organic matter content of Lolium multiflorum+ Vicia villosa reaching 26.69 g·kg ^-1;The activities of soil urease,alkaline phosphatase,catalase were increased ( P<0.05),with Lolium multiflorum+ Vicia villosa having the most significant effect ( P<0.05). The bacterial beta diversity and the interaction relationship between bacterial communities in artificial cover cropping measures increased,while the abundance of metabolic functional genes in organismal systems significantly decreased( P<0.05). In summary,planting Lolium multiflorum+ Vicia villosa. and Lolium multiflorum+ Astragalus sinicus in organic kiwifruit orchards in the Guanzhong area can enhance the soil micro-ecological environment.