The invasive plant Cenchrus pauciflorus Benth exhibits strong adaptability to stress, especially drought. When newly introduced certain plant species can become invasive and quickly spread in an area due to lack of competition, potentially disturbing the ecological balance and species diversity. C. pauciflorus has been known to cause huge economic losses to agriculture and animal husbandry. Thus, understanding the physiological responses of C. pauciflorus to drought stress could help explore the role of C. pauciflorus in population expansion in sandy land environments. In this study, we evaluated the response of C. pauciflorus to induced low, moderate, and severe drought stress conditions. Results showed a linear reduction in the fresh weight (FW), dry weight (DW), and relative water content (RWC) of the aboveground parts of C. pauciflorus following drought stress as compared to the control plants (no drought stress). Chemical analyses showed that the drought treatments significantly induced the production of proline, soluble proteins, soluble sugars, MDA, and free amino acids as compared to the control treatment (no drought stress). On the other hand, the starch content was significantly reduced in drought-treated plants. This was also accompanied by a significant linear increase in the antioxidant enzyme activities (SOD, POD, and CAT) in plants subjected to drought stress. On the basis of physiological and biochemical analyses, we propose that C. pauciflorus has evolved to survive harsh drought stress conditions of the desert via sophisticated biochemical adjustment and antioxidant reprograming that allows protection against damage caused by drought stress.

The success of a biological invasion relies on the environment and is closely linked to factors such as water and temperature. Invasive plant species display different seed characteristics, including shape. Field sandbur (Cenchrus pauciflorus) is a globally widespread invasive species capable of adapting to broad environmental conditions. However, its germination response to water and temperature still remains unclear. C. pauciflorus contains two seeds in the same bur that differ in size: big seeds (M) and small seeds (P). Separate greenhouse experiments were conducted under different temperature regimes (0/10°C, 5/15°C, 10/20°C, 15/25°C, 18/28°C, 20/30°C and 25/35°C) and water potentials (-1.50Mpa, -1.00Mpa, -0.75Mpa, -0.50Mpa, -0.25Mpa and 0Mpa) for M and P seeds. The results support the hypothesis that germination of C. pauciflorus is significantly influenced by seed type, temperature and water potential. M and P seeds responded differently to varied alternative temperatures and water potentials. However, M and P seeds were more sensitive to water potential than to temperature. Optimal conditions for M and P seed germination were measured at 25/35°C (night temperature/day temperature) and 20/30°C, respectively. In contrast, the highest germination rate was observed for the 0Mpa of the water potential treatment. Additionally, base temperature (T_base) and base water potential (W_base) were lower for M (7.7°C, -1.11Mpa at 10/20°C, and -1.07Mpa at 20/30°C) than for P (9.4°C, -0.92Mpa at 10/20°C, and -0.52Mpa at 20/30°C). These different germination strategies of M and P seeds with respect to temperature and water potential increased overall plant propagation. These results indicate that tropical and subtropical regions water potentials beyond -0.50Mpa (10/20°C) or -1.00Mpa (20/30°C) face a potential risk of C. pauciflorus invasion.

Against the background of global warming, trees in high-latitude and high-altitude areas are more sensitive to rapid warming. Revealing the response patterns of trees at different altitudes to rapid warming in typical alpine mountain environments can help to predict the future distribution of forests in the region and the associated changes in the timberline. This study used tree-ring width data (band sampling) from Dahurian larch (Larix gmelinii Rupr.) along an altitudinal gradient (970–1409 m) on Oakley Mountain to establish 10 chronologies and to analyze the growth–climate response of larch to warming and altitudinal changes along a gradient. The results showed that before rapid warming, larch growth was strongly influenced mainly by precipitation in July–August, while after warming, the growth was controlled mainly by precipitation (snowfall) in winter (October–April) and showed a significant positive correlation with the SPEI in winter and a negative correlation with temperature in February–April (early spring). This indicates that the rapid warming event led to a drastic change in the water heat balance during the pre-growth period of the trees in the study area, which shifted the tree growth from being restricted by drought in the growing season before warming to being restricted by winter drought (i.e., the lagged effect of snowfall in the pre-growing season) after warming and that the trees at low altitudes suffered from more severe winter drought. In the future, as the global climate warms further, the growth of mountain larch at low altitudes (below 1200 m) will continue to decrease, and the coupling of winter snowfall and seasonal (February–April) warming will increase the upper altitude limit at which winter drought occurs for larch in the study area; additionally, larch at higher altitudes will be able to cope with this ecological process better.

MicroRNAs (miRNAs) function as vital regulators of diapause in insects through their ability to post-transcriptionally suppress target gene expression. In this study, the miRNA of Ostrinia furnacalis, an economically important global crop pest species, was characterized. For the included analyses, 9 small RNA libraries were constructed using O. furnacalis larvae in different diapause states (non-diapause, ND; diapause, D; diapause-termination, DT). The results identified 583 total miRNAs, of which 256 had previously been identified, whereas 327 were novel. Furthermore, comparison analysis revealed that 119 and 27 miRNAs were differentially expressed in the D vs. ND and DT vs. D, respectively. Moreover, the expression patterns of their miRNAs were also analyzed. GO and KEGG analysis of the target genes of differentially expressed miRNAs highlighted the importance of these miRNAs as diapause regulators in O. furnacalis, especially through metabolic processes, endocrine processes, 20-hydroxyecdysone, and circadian clock signaling pathways. In summary, this study highlighted the involvement of specific miRNAs in the control of diapause in O. furnacalis. To the best of our knowledge, this is the first study to identify miRNA expression patterns in O. furnacalis, thereby providing reference and novel evidence enhancing our current understanding of how small RNAs influence insect diapause.

The increasing prevalence of antibiotic-resistant Escherichia coli underscores the need for alternative antimicrobial strategies derived from natural food sources. Koumiss, a traditional fermented dairy product, represents a promising reservoir of bioactive peptides. This study evaluated the antibacterial activity and biological effects of a novel koumiss-derived peptide, MP-4, against E. coli-induced infectious diarrhea. Antibacterial efficacy was assessed in vitro using MIC, minimum bactericidal concentration (MBC), growth kinetics, scanning electron microscopy, and ion leakage analyses, while protective effects were further examined in a murine infection model. The MP-4 exhibited pronounced antibacterial activity against E. coli, accompanied by morphological changes consistent with altered membrane integrity. In vivo administration of MP-4 was associated with reduced BW loss, attenuation of intestinal villus damage, and reduction of epithelial apoptosis in infected mice. Integrated metabolomic and transcriptomic analyses revealed broad alterations in host metabolic profiles and gene expression patterns following MP-4 treatment, with differentially regulated metabolites mainly associated with AA and lipid metabolism and altered gene expression enriched in circadian rhythm-related pathways. Notably, lysine degradation emerged as a central pathway, showing coordinated changes at both the metabolic and transcriptional levels. Collectively, these findings suggest that MP-4 is a food-derived bioactive peptide with antibacterial activity and host-associated biological effects during intestinal infection, highlighting the potential of traditional fermented dairy products as functional resources for dietary intervention against enteric pathogens.