Institute of Grassland Research

This study evaluated the effects of Lactic acid bacteria and cellulase, individually and in combination, on fermentation quality and microbial community dynamics of alfalfa silage. Six treatments were tested, including control, cellulase alone and two lactic acid bacteria species (Pediococcus pentosaceus, Levilactobacillus brevis) applied individually or in combination with cellulase. The results showed that Levilactobacillus brevis in combination with cellulase, producing higher lactic acid concentrations, lower pH (< 4.2) to the other treatments. The microbiome analysis revealed that Lactiplantibacillus was dominant, while undesirable bacterium Achromobacter was suppressed. Functional prediction of microbial communities analysis indicated a higher predicted abundance of sequences associated with pyruvate metabolism, glycolysis/gluconeogenesis and starch and sucrose metabolism pathways. These findings provide insights into optimizing alfalfa silage quality through synergistic use of cellulase and lactic acid bacteria silage inoculants with high metabolic stability.

Accurate extraction of crop planting structures is important for crop area and yield estimation, but complex and fragmented cropping patterns with overlapping phenology in the Hetao Irrigation District hinder reliable crop discrimination. This study proposes a hierarchical workflow that integrates vegetation masking with multi-source feature optimization for crop mapping. First, dual-temporal Sentinel-2 imagery (May and August) is used to generate a vegetation region-of-interest(ROI) mask via Otsu thresholding applied to the Normalized Difference Vegetation Index (NDVI), combined with pixel-wise maximum-value fusion to reduce phenology-driven omissions and background interference. Second, within the vegetation mask, Sentinel-2 spectral, vegetation-index, and texture features are combined with Sentinel-1 synthetic aperture radar (SAR) backscatter and SAR texture features to construct a multi-source feature set. Random Forest(RF) feature-importance ranking is used to select an effective feature subset, and four classifiers (RF, support vector machine (SVM), eXtreme Gradient Boosting (XGBoost), and convolutional neural network (CNN)) are compared under the same training/validation setting. The vegetation extraction achieves an overall accuracy of 91% (Kappa = 0.80). Using Sentinel-2 features only, the optimized subset with CNN attains the best performance (overall accuracy = 95%, Kappa = 0.93). Adding Sentinel-1 SAR texture features provides an additional improvement (overall accuracy = 96%, Kappa = 0.94), particularly for classes prone to confusion in fragmented plots. Area proportions derived from the final map are consistent with statistical yearbook data (percentage errors: maize 3.45%, sunflower 2.66%, wheat 0.11%, tomato 0.92%) under the study conditions. This workflow supports practical crop-structure monitoring in complex irrigation districts.

MT mitigates Cd toxicity by enhancing photosystem and antioxidant system activities, and related gene expression in GCC. NAC, HSF, and MYB-related families may play key roles in MT-induced Cd tolerance. Cadmium (Cd), a toxic heavy metal non-essential to plants, has detrimental impacts on both the environment and human health. Melatonin (MT) plays an important protective role in plants against stresses such as heavy metal toxicity. However, the detailed mechanism underlying MT alleviating Cd toxicity remains unclear in ground-cover chrysanthemum (Chrysanthemum morifolium Ramat., GCC). GCC seedlings were pre-treated with MT solution (150 μM) via foliar spraying and subsequently grown under Cd stress, after which the growth, physiological, and transcriptomic responses of the plant were investigated. The results demonstrated that MT pre-treatment inhibited the Cd-induced chlorophyll degradation in GCC seedlings, while it enhanced chlorophyll synthesis and related gene expression by promoting electron transfer efficiency and maintaining the integrity of the oxygen-evolving complex in photosynthesis. Furthermore, MT + Cd treatment upregulated 11 photosystem I (PSI), 13 PSII, eight light-harvesting complex I (LHCI), and 20 LHCII-related genes as compared with Cd treatment alone. MT also alleviated oxidative stress and boosted antioxidant capacity by conserving the activities and gene expression levels of superoxide dismutase, peroxidase, and key enzymes in the ascorbate-glutathione cycle and thioredoxin-peroxiredoxin pathway. In addition, MT reduced the generation rate of O2·- by 27.64%, malondialdehyde by 68.36%, and H2O2 by 44.97%, alleviating the Cd-induced damage. Weighted gene co-expression network analysis provided additional evidence that MT improved GCC tolerance to Cd by modulating the expression of transcription factors (e.g., NAC, HSF, and MYB-related families) related to abiotic stress.

BackgroundTrehalose 6-phosphate (Tre6P) synthase (TPS) and Tre6P phosphatase (TPP) are two key enzymes involved in the trehalose synthesis pathway in plants. However, the identification and research of TPS and TPP gene families in rye are still limited.ResultsIn this study, a total of 10 TPS genes and 9 TPP genes were identified based on the Lo7 genome database. According to phylogenetic analysis, ScTPS and ScTPP proteins from rye were more closely related to wheat, barley and other Triticeae species, and the fragment replication events might be the main driver of gene family expansion and new function generation during ScTPS and ScTPP genes evolution. Cis-element analysis revealed that ScTPS and ScTPP genes showed more stress-related cis-element distribution in rye, and some members of the ERF, MYB, bZIP, and C2H2 transcription factor families may play potential regulatory roles. Protein–protein interaction network analysis revealed that ScTPS07, ScTPS08, ScTPS09 and ScTPS10 might be hub genes in the rye trehalose synthesis pathway. RNA-seq and qRT-PCR analyses show that low temperature induces ScTPS and ScTPP expression; most genes reach maximal expression at 12–24 h; expression differs between roots and leaves of rye seedlings.ConclusionsThis study provided a molecular basis for trehalose synthesis in rye by identifying members of the ScTPS and ScTPP gene families, provided insights into the mechanism of cold stress tolerance of this substance in rye by preliminary analysis of the expression patterns of these genes under low temperature stress.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12864-025-12514-9.

With the development of smart agriculture, articulated tractors are increasingly applied in hilly and mountainous areas, where precise path tracking under lateral slippage remains a major challenge. Due to the articulated structure, the front and rear vehicle bodies exhibit different responses to terrain disturbances, making conventional single-point reference tracking insufficient for accurately describing whole-vehicle deviation. To address this issue, this study proposes a novel multi-point tracking deviation index that integrates the deviations of the front axle center, articulation point, and rear axle center. Based on this index, a systematic comparison of different reference points, including the centroid, incenter, and circumcenter of the characteristic triangle, is conducted through co-simulation experiments. The results demonstrate that the centroid yields the smallest whole-vehicle comprehensive deviation, achieving average deviations of 0.040 and 0.037 m under U -shaped and closed-curve paths, respectively, corresponding to reductions of 87% and 88% compared with the traditional articulation-point-based method. These findings indicate that the centroid provides the most balanced and robust reference point for articulated tractor path tracking under terrain-induced slippage, offering an effective trade-off between tracking accuracy and computational efficiency for autonomous operations in complex agricultural environments.

Comfrey (Symphytum officinale L.) was a promising crop in the integrated crop-livestock pattern. However, the impact of long-term irrigation with treated poultry wastewater (TPW) on soil chemical properties and bacterial community, as well as the contribution of comfrey to mitigate N accumulation in soil, remain unclear. This study investigated the changes in chemical and microbiological characteristics of the comfrey soil under six-year TPW irrigation (grassland) in comparison with the adjacent conventional crop soil irrigated with freshwater (farmland). Results showed that N accumulation in comfrey accounted for 66.0% of the N input from TPW irrigation. In grassland, soil pH at all depths increased by one unit and EC in the subsoil increased by 33.5-42.4%, while TN and NO3--N in the surface soil decreased by 26.7% and 64.5%, respectively. The composition and structure of the bacterial community in the grassland dramatically changed, and the relative abundances of nitrite-oxidizing bacteria Nitrospira and ammonifying bacterium Flavobacterium and Pseudomonas increased by 0.1-3.6-, 3.8-11.0- and 0.1-6.0-fold, respectively, while those of saline-alkali-sensitive bacteria Sphingomonas decreased by 72.3-83.2% in the subsoil. Soil pH and NO3--N were the primary factors influencing changes in bacterial communities. These findings revealed that there was no nitrogen accumulation, but alkalization occurred in the comfrey field under long-term TPW irrigation, which highlighted the prospective application of comfrey in the crop-livestock system.

UDP-N-acetylglucosamine pyrophosphorylase (UAP) is an essential enzyme in the insect chitin biosynthesis pathway; however, little is known regarding its molecular functions in Oedaleus asiaticus Bey-Bienko (Orthoptera: Acrididae). Here, two UAP genes, OaUAP1 and OaUAP2, were identified and characterized in O. asiaticus. The effects of exogenous treatments, including the molting hormone 20-hydroxyecdysone (20E) and the chitin biosynthesis inhibitor validamycin (VA), were assessed on chitin synthesis. Sequence analyses have shown that the cDNA and deduced amino acid sequences of O. asiaticus share over 90% identity with UAPs in Locusta migratoria. OaUAP1 and OaUAP2 are widely expressed in many tissues and developmental stages but exhibit different expression patterns: OaUAP1 shows higher expression in the epidermis and fifth-instar nymphs, while OaUAP2 is primarily expressed in the fat body and in the fifth-instar nymphs and adults. The functional analysis of two OaUAPs revealed that OaUAP2 was crucial in molting; moreover, its implication also exists in other biosynthetic processes since nymphs maintained normal growth and development. Both OaUAP expressions were upregulated by 20E and downregulated by VA in the chitin biosynthesis pathway. Our findings provide a vital molecular insight into the chitin biosynthesis pathway of O. asiaticus and lay a solid foundation for developing environmentally safe biological insecticides.