Xanthium spinosum (X. spinosum) is a highly invasive weed native to South America and distributed in 17 provinces (municipalities) of China. It has severely negative influences on ecosystems, agriculture, and husbandry. However, few studies have reported on the impact of human activity and climate change on the future distribution and centroid shift of X. spinosum. This study aimed to investigate the potential geological distribution of X. spinosum in China, as well as the distribution pattern, centroid shift, and key environmental factors influencing its distribution, under four future climate scenarios (SSP1-26, SSP2-45, SSP3-70, and SSP5-85) based on the biomod2-integrated model. The results indicated that the suitable habitats for X. spinosum would expand in the future, mainly in Inner Mongolia, Northeast China, and the plateau regions (e.g., Xinjiang and Xizang). Under future climate scenarios, the centroid would shift toward the northwest or northeast part of China, with the SSP2-45-2050s scenario showing the maximum shift distance (161.990 km). Additionally, the key environmental variables influencing the distribution of X. spinosum, including human impact index, bio5, bio7, and bio12, were determined, revealing that most of them were related to human activities, temperature, and precipitation. This study enhances the understanding of the influence of human activity and climate change on the geographic range of X. spinosum. It provides references for early warning and management in the control of X. spinosum.

Grassland which covers 40% of terrestrial land is an important ecosystem having a multitude of functions, which has suffered various degrees of degradation with the interaction between global climate change and unreasonable human utilization (e.g., grazing and reclamation). Improved understanding of soil and microbial community diversity during meadow steppe degradation is crucial for predicting degradation mechanisms and restoration strategies. Here, we used Illumina sequencing technology to investigate the patterns of soil microbial community structure and the driving factors of its change across different degradation degrees of meadow steppe [i.e., non-degraded grasslands (NDG), lightly degraded grasslands (LDG), moderately degraded grasslands (MDG), and severely degraded grasslands (SDG)] south of the Greater Khingan Mountains. Our results showed a significant variation in soil properties, enzyme activity, and soil metal elements across the degraded meadows. Soil available phosphorus (AP), urease (UE), and cellulase (CL) in soils increased with the intensity of grassland degradation. Grassland degradation significantly decreased soil bacterial and fungal richness. In addition, grassland degradation significantly increased the relative abundance of Firmicutes (from 1.65% to 5.38%) and Myxococcota (from 2.13% to 3.13%). Degradation considerably increased the relative abundance of Ascomycota (from 66.54% to 75.05%), but decreased Basidiomycota (from 18.33% to 9.92%). The relative abundance of nitrogen fixation and cellulolysis decreased significantly due to grassland degradation. For fungal functional guilds, the relative abundance of pathotrophs increased while saprotrophs decreased significantly with increasing severity of degradation. Total nitrogen (TP), AP, available potassium (AK), manganese (Mn), lead (Pb), UE, sucrase (SC), and alcalase protease (ALPT) were the main drivers of soil bacterial community composition, while TP, AP, AK, Pb, UE, and SC were the main drivers of soil fungal community composition in the degraded grassland. Our findings demonstrated that severe grassland degradation has an enormous effect on soil microbial communities and soil physicochemical dynamics. These findings improve our theoretical understanding of the interactions between soil microbial populations and soil environmental variables in degraded grassland.

Lepidopteran insects mainly rely on sex pheromones to complete sexual communications. Pheromone receptors (PRs) are expressed on the olfactory receptor neurons (ORNs) of the sensilla trichodea and play an essential role in sexual communication. Despite extensive investigations into the mechanisms of peripheral recognition of sex pheromones in Lepidoptera, knowledge about these mechanisms in L. sticticalis remains limited. In this study, five candidate LstiPRs were analyzed in a phylogenetic tree with those of other Lepidopteran insects. Electroantennography (EAG) assays showed that the major sex pheromone component E11-14:OAc elicited a stronger antennal response than other compounds in male moths. Moreover, two types of neurons in sensilla trichodea were classified by single sensillum recordings, of which the “a” neuron specifically responded to E11-14:OAc. Five candidate PRs were functionally assayed by the heterologous expression system of Xenopus oocytes, and LstiPR2 responded to the major sex pheromone E11-14:OAc. Our findings suggest that LstiPR2 is a PR sensitive to L. sticticalis’s major sex pheromone compound, E11-14:OAc. Furthermore, this study offers valuable insights into the sexual communication behavior of L. sticticalis, forming a foundation for further analysis of the species’ central nervous system.

Smooth bromegrass (Bromus inermis Leyss.) is an excellent forage species widely distributed in Gansu, Qinghai, Inner Mongolia, and other provinces of China (Gong et al. 2019). In July 2021, typical...

Introduction: Increasing the research on the development and utilization of unconventional feed resources is one of the effective ways for the sustainable development of herbivorous animal husbandry. China is one of the countries most severely impacted by the invasion of the alien plant Solanum rostratum Dunal (S. rostratum), but this resource has not been used effectively.Methods: The aim of this study was to investigate the effects of Lactobacillus plantarum and cellulase on the fermentation quality and microbial community in mixed silage of S. rostratum and alfalfa. Treatments were a control treatment with no additive (CK), Lactobacillus plantarum (LP), cellulase (CE), and Lactobacillus plantarum in combination with cellulase (L+C), all of which were stored at ambient temperature for 7, 15, 30, and 60 days.Results: The results showed that the mixture could retain dry matter (DM), crude protein (CP), and water soluble carbohydrates (WSC) content, increase lactic acid (LA) content, decrease pH and alkaloid content, and improve fermentation quality during silage. The use of additives increased the abundance of Lactobacillus and Weissella, which was related to the improvement of the quality of mixed silage and the degradation of total alkaloids. Differential microbial functions were mainly carbohydrate metabolism, biosynthesis of secondary metabolites and carbon metabolism.Conclusion: The application of additives and mixed silage provides a new idea for the feed utilization of S. rostratum.

Sandbur [Cenchrus longispinus (Hack.) Fernald] is a major invasive weed in the agro-pastoral ecotone of northern China. It propagates via seeds encased in spiny burs. Each bur encloses a pair of seeds, and the larger M-type seeds germinate first, functioning as pioneer plants, while smaller P-type seeds remain dormant. Thus, the rapid germination of M-type seeds is pivotal for population sustenance. In this study, we investigated the transcription response involved in the germination of C. longispinusus M-type seeds during four stages (drying, imbibition, exposure, and sprouting). A total of 24,399 DEGs were identified by comparing two consecutive germination stages, with most DEGs found in the imbibition stage. GO enrichment analysis showed that the DEGs were mainly enriched in substance metabolic and regulatory processes. Correspondingly, KEGG enrichment analysis indicated that the functions of DEGs were significantly concentrated in secondary metabolite synthesis pathways, as well as substance and energy metabolic pathways. Notably, the expression of starch-and-sugar metabolism-related genes increased as germination progressed. Additionally, ABA synthesis-related genes were notably downregulated, while those regulating ABA catabolism were significantly upregulated. Moreover, GA synthesis-related genes were activated, especially in the imbibition stage, with nine GA20ox genes highly expressed. These research findings help us gain a deeper understanding of the seed germination mechanism of C. longispinus.