Background and Aims: The North China Plain, the highest winter-wheat-producing region of China, is seriously threatened by drought. Traditional irrigation wastes a significant amount of water during the sowing season. Therefore, it is necessary to study the drought resistance of wheat during germination to maintain agricultural ecological security. From several main cultivars in the North China Plain, we screened the drought-resistant cultivar JM47 and drought-sensitive cultivar AK58 during germination using the polyethylene glycol (PEG) drought simulation method. An integrated analysis of the transcriptome and metabolomics was performed to understand the regulatory networks related to drought resistance in wheat germination and verify key regulatory genes.Methods: Transcriptional and metabolic changes were investigated using statistical analyses and gene–metabolite correlation networks. Transcript and metabolite profiles were obtained through high-throughput RNA-sequencing data analysis and ultra-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry, respectively.Key Results: A total of 8083 and 2911 differentially expressed genes (DEGs) and 173 and 148 differential metabolites were identified in AK58 and JM47, respectively, under drought stress. According to the integrated analysis results, mammalian target of rapamycin (mTOR) signalling was prominently enriched in JM47. A decrease in α-linolenic acid content was consistent with the performance of DEGs involved in jasmonic acid biosynthesis in the two cultivars under drought stress. Abscisic acid (ABA) content decreased more in JM47 than in AK58, and linoleic acid content decreased in AK58 but increased in JM47. α-Tocotrienol was upregulated and strongly correlated with α-linolenic acid metabolism.Conclusions: The DEGs that participated in the mTOR and α-linolenic acid metabolism pathways were considered candidate DEGs related to drought resistance and the key metabolites α-tocotrienol, linoleic acid and l-leucine, which could trigger a comprehensive and systemic effect on drought resistance during germination by activating mTOR–ABA signalling and the interaction of various hormones.

Although tauroursodeoxycholic acid (TUDCA) has been widely studied in mammalian cells because of its role in inhibiting apoptosis, its effects on plants remain almost unknown, especially in the case of crops such as wheat. In this study, we conducted a series of experiments to explore the effects and mechanisms of action of TUDCA on wheat growth and cell death induced by osmotic stress. Our results show that TUDCA: 1) ameliorates the impact of osmotic stress on wheat height, fresh weight, and water content; 2) alleviates the decrease in chlorophyll content as well as membrane damage caused by osmotic stress; 3) decreases the accumulation of reactive oxygen species (ROS) by increasing the activity of antioxidant enzymes under osmotic stress; and 4) to some extent alleviates osmotic stress–induced cell death probably by regulating endoplasmic reticulum (ER) stress–related gene expression, for example expression of the basic leucine zipper genes bZIP60B and bZIP60D, the binding proteins BiP1 and BiP2, the protein disulfide isomerase PDIL8-1, and the glucose-regulated protein GRP94. We also propose a model that illustrates how TUDCA alleviates osmotic stress–related wheat cell death, which provides an important theoretical basis for improving plant stress adaptation and elucidates the mechanisms of ER stress–related plant osmotic stress resistance.

Phosphorus deficiency critically constrains crop growth. Soil microbial diversity, which is crucial for maintaining terrestrial ecosystem integrity, plays a key role in promoting soil P cycling. Therefore, it is imperative to understand the survival strategies of microorganisms under P-limited conditions and explore their roles in community regulation. We initiated a comprehensive, long-term, in situ wheat field experiment to measure soil physicochemical properties, focusing on the different forms of soil inorganic P. Subsequently, 16S rRNA and ITS marker sequencing was employed to study changes in soil microbial abundance and community structure and predict functional alterations. The results showed that soil water and P deficiencies significantly affected wheat growth and development, soil physicochemical properties, and microbial diversity and function. Prolonged P deficiency lowered soil pH, significantly increasing phosphatase content (58%) under W1 (normal irrigation) conditions. Divalent calcium phosphate decreased significantly under W0 (lack of irrigation) and W1 conditions, and the most stable ten-valent calcium phosphate began to transform under W0 conditions. Soil microbial diversity increased (e.g., Proteobacteria and Vicinamibacterales) and enhanced the transport capacity of bacteria. P deficiency affected the coexistence networks between bacteria and fungi, and SEM (structural equation modeling) analysis revealed a stronger correlation in bacteria (r² = 0.234) than in fungi (r² = 0.172). In soils deprived of P for 7 years, the soil P content and forms were coupled with microbial changes. Microorganisms exhibited community and functional changes in response to low-phosphorus soil, concurrently influencing soil P status. This study enhances our understanding of rhizospheric processes in soil P cycling under microbial feedback, particularly the impact of microbial interactions on changes in soil P forms under P-limited conditions.