Expansin is a cell wall relaxant protein that is common in plants and directly or indirectly participates in the whole process of plant root growth, development and morphogenesis. A well-developed root system helps plants to better absorb water and nutrients from the soil while effectively assisting them in resisting osmotic stress, such as salt stress. In this study, we observed and quantified the morphology of the roots of Arabidopsis overexpressing the TaEXPAs gene obtained by the research group in the early stage of development. We combined the bioinformatics analysis results relating to EXPA genes in five plants and identified TaEXPA7-B, a member of the EXPA family closely related to root development in winter wheat. Subcellular localization analysis of the TaEXPA7-B protein showed that it is located in the plant cell wall. In this study, the TaEXPA7-B gene was overexpressed in rice. The results showed that plant height, root length and the number of lateral roots of rice overexpressing the TaEXPA7-B gene were significantly higher than those of the wild type, and the expression of the TaEXPA7-B gene significantly promoted the growth of lateral root primordium and cortical cells. The plants were treated with 250 mM NaCl solution to simulate salt stress. The results showed that the accumulation of osmotic regulators, cell wall-related substances and the antioxidant enzyme activities of the overexpressed plants were higher than those of the wild type, and they had better salt tolerance. This paper discusses the effects of winter wheat expansins in plant root development and salt stress tolerance and provides a theoretical basis and relevant reference for screening high-quality expansin regulating root development and salt stress resistance in winter wheat and its application in crop molecular breeding.

Potatoes are one of the most important food crops worldwide, but their growth and development are often seriously threatened by potato bacterial wilt. The wettable powder produced by Bacillus amyloliquefaciens C4 under optimized fermentation conditions effectively inhibits potato bacterial wilt. In this study, lipopeptide antibiotics were identified via PCR and MALDI-TOF-MS, and their antibacterial activity was determined. The optimal formulation of C4 wettable powder was optimized via a single-factor experiment combined with a response surface. The effect of C4 wettable powder on potato bacterial wilt was evaluated. In the antibacterial activity test, surfactin showed better inhibition ability. After determining the optimal liquid fermentation conditions and wettable powder formula, the surfactin activity increased to 540.15 mg/L, and the C4 wettable powder activity reached 69.67 × 10⁸ cfu/g. The results of the pot experiment showed that the best cost-effectiveness was achieved under 500 times dilution and spraying, with a control effect of 79.05 ± 24.79%. The physiological and biochemical results showed that C4 wettable powder could induce rapid defense enzyme responses in leaves and enhance plant resistance to pathogenic bacteria. The results showed that C4 wettable powder effectively controlled potato bacterial wilt, and its application method was determined.

The fermentation of fresh strawberries into fruit wine offers a solution to the seasonal surplus of strawberries. 2-phenylethanol is a key compound influencing the flavor profile of fruit wines, and elevating its content can enhance both flavor complexity and body quality. In this study, we established the optimal process of fermenting strawberry wine using the 2-phenylethanol (3.9 g/L) tolerant S. cerevisiae AFRC01 strain. Under optimal conditions, the 2-phenylethanol content reached 170.06 mg/L, representing a 33% increase compared to the unoptimized process. Wine fermented with S. cerevisiae AFRC01 exhibited reduced astringency and aftertaste alongside enhanced richness and freshness compared with that fermented with S. cerevisiae CICC33253. A further analysis of the gene expression patterns in the 2-phenylethanol synthesis pathway under 2-phenylethanol stress (1.0 g/L) revealed no significant stress-responsive changes in S. cerevisiae AFRC01, suggesting its mechanism of tolerance is minimally associated with regulation of this pathway. Subsequent genome sequencing identified mutations in the glycolytic pathway genes involved in synthesizing phosphoenolpyruvate (the 2-phenylethanol precursor) in S. cerevisiae AFRC01 compared with S. cerevisiae CICC33253. This study provides a foundation for the later promotion and application of 2-phenylethanol tolerant S. cerevisiae AFRC01.