Genome‐wide associated study identifies FtPMEI13 gene conferring drought resistance in Tartary buckwheat

• Published in: The Plant journal : for cell and molecular biology 2024-12, Vol.120 (6), p.2398-2419
• Main Authors: He, Jiayue, Hao, Yanrong, He, Yuqi, Li, Wei, Shi, Yaliang, Khurshid, Muhammad, Lai, Dili, Ma, Chongzhong, Wang, Xiangru, Li, Jinbo, Cheng, Jianping, Fernie, Alisdair R., Ruan, Jingjun, Zhang, Kaixuan, Zhou, Meiliang
• Format: Article
• Language: English
• Subjects: Abscisic acid; Abscisic Acid - metabolism; Arabidopsis; Breeding; Buckwheat; Carboxylic Ester Hydrolases - genetics; Carboxylic Ester Hydrolases - metabolism; Cell walls; Crop yield; Domestication; Drought; Drought Resistance; drought tolerance; Droughts; Electrophoretic mobility; Fagopyrum - genetics; Fagopyrum - metabolism; Fagopyrum - physiology; Fagopyrum tataricum; FtPMEI13; Gene Expression Regulation, Plant; genes; Genome-wide association studies; Genome-Wide Association Study; Genomes; genotype; Genotypes; Germplasm; Growth conditions; GWAS; Metabolites; Pectin; Pectinesterase; pectins; Plant Proteins - genetics; Plant Proteins - metabolism; Stomata; stomatal movement; Stress, Physiological - genetics; Tartary buckwheat; transcription factors; water stress; Yeasts
• ISSN: 0960-7412; 1365-313X; 1365-313X
• DOI: 10.1111/tpj.17119

SUMMARY Tartary buckwheat is known for its ability to adapt to intricate growth conditions and to possess robust stress‐resistant properties. Nevertheless, it remains vulnerable to drought stress, which can lead to reduced crop yield. To identify potential genes involved in drought resistance, a genome‐wide association study on drought tolerance in Tartary buckwheat germplasm was conducted. A gene encoding pectin methylesterase inhibitors protein (FtPMEI13) was identified, which is not only associated with drought tolerance but also showed induction during drought stress and abscisic acid (ABA) treatment. Further analysis revealed that overexpression of FtPMEI13 leads to improved drought tolerance by altering the activities of antioxidant enzymes and the levels of osmotically active metabolites. Additionally, FtPMEI13 interacts with pectin methylesterase (PME) and inhibits PME activity in response to drought stress. Our results suggest that FtPMEI13 may inhibit the activity of FtPME44/FtPME61, thereby affecting pectin methylesterification in the cell wall and modulating stomatal closure in response to drought stress. Yeast one‐hybrid, dual‐luciferase assays, and electrophoretic mobility shift assays demonstrated that an ABA‐responsive transcription factor FtbZIP46, could bind to the FtPMEI13 promoter, enhancing FtPMEI13 expression. Further analysis indicated that Tartary buckwheat accessions with the genotype resulting in higher FtPMEI13 and FtbZIP46 expression exhibited higher drought tolerance compared to the others. This suggests that this genotype has potential for application in Tartary buckwheat breeding. Furthermore, the natural variation of FtPMEI13 was responsible for decreased drought tolerance during Tartary buckwheat domestication. Taken together, these results provide basic support for Tartary buckwheat breeding for drought tolerance. Significance Statement Our study identifies the drought‐resistant gene FtPMEI13 in Tartary buckwheat through GWAS during the seed germination stage and demonstrates its significant role in enhancing drought tolerance. Our findings enhance the understanding of the genetic mechanisms underlying drought resistance in Tartary buckwheat and provide valuable genetic resources and strategies for drought resistance breeding, and this information helps for the gene selection of Tartary buckwheat varieties for further use in Tartary buckwheat breeding program.