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Summary: Abscisic acid (ABA) receptors are considered as the targeted manipulation of ABA sensitivity and water productivity in plants. Regulation of their stability or activity will directly affect ABA signalling. Mitogen‐activated protein kinase (MAPK) cascades link multiple environmental and plant developmental cues. However, the molecular mechanism of ABA signalling and MAPK cascade interaction remains largely elusive.TaMPK3 overexpression decreases drought tolerance and wheat sensitivity to ABA, significantly weakening ABA's inhibitory effects on growth. Under drought stress, overexpression lines show lower survival rates, shoot fresh weight and proline content, but higher malondialdehyde levels at seedling stage, as well as decreased grain width and 1000 grain weight in both glasshouse and field conditions at the adult stage. TaMPK3‐RNAi increases drought tolerance.TaMPK3 interaction with TaPYL4 leads to decreased TaPYL4 levels by promoting its ubiquitin‐mediated degradation, whereas ABA treatment diminishes TaMPK3–TaPYL interactions. In addition, the expression of ABA signalling proteins is impaired in TaMPK3‐overexpressing wheat plants under ABA treatment. The MPK3‐PYL interaction module was found to be conserved across monocots and dicots.Our results suggest that the MPK3‐PYL module could serve as a negative regulatory mechanism for balancing appropriate drought stress response with normal plant growth signalling in wheat. [ABSTRACT FROM AUTHOR]

TIFY proteins play crucial roles in plant abiotic and biotic stress responses. Our transcriptome data revealed several TIFY family genes with significantly upregulated expression under drought, salt, and ABA treatments. However, the functions of the GmTIFY family genes are still unknown in abiotic stresses. We identified 38 GmTIFY genes and found that TIFY10 homologous genes have the most duplication events, higher selection pressure, and more obvious response to abiotic stresses compared with other homologous genes. Expression pattern analysis showed that GmTIFY10e and GmTIFY10g genes were significantly induced by salt stress. Under salt stress, GmTIFY10e and GmTIFY10g transgenic Arabidopsis plants showed higher root lengths and fresh weights and had significantly better growth than the wild type (WT). In addition, overexpression of GmTIFY10e and GmTIFY10g genes in soybean improved salt tolerance by increasing the PRO, POD, and CAT contents and decreasing the MDA content; on the contrary, RNA interference plants showed sensitivity to salt stress. Overexpression of GmTIFY10e and GmTIFY10g in Arabidopsis and soybean could improve the salt tolerance of plants, while the RNAi of GmTIFY10e and GmTIFY10g significantly increased sensitivity to salt stress in soybean. Further analysis demonstrated that GmTIFY10e and GmTIFY10g genes changed the expression levels of genes related to the ABA signal pathway, including GmSnRK2 , GmPP2C , GmMYC2 , GmCAT1 , and GmPOD. This study provides a basis for comprehensive analysis of the role of soybean TIFY genes in stress response in the future. [ABSTRACT FROM AUTHOR]