摘要
Cultivating high-yield wheat under limited water resources is crucial for sustainable agriculture in semiarid regions.Amid water scarcity,plants activate drought response signaling,yet the delicate balance between drought tolerance and development remains unclear.Through genome-wide association studies and transcriptome profiling,we identified a wheat atypical basic helix-loop-helix(b HLH)transcription factor(TF),Tab HLH27-A1,as a promising quantitative trait locus candidate for both relative root dry weight and spikelet number per spike in wheat.Tab HLH27-A1/B1/D1 knockout reduced wheat drought tolerance,yield,and water use efficiency(WUE).Tab HLH27-A1 exhibited rapid induction with polyethylene glycol(PEG)treatment,gradually declining over days.It activated stress response genes such as Ta CBL8-B1 and Ta CPI2-A1 while inhibiting root growth genes like Ta SH15-B1 and Ta WRKY70-B1 under short-term PEG stimulus.The distinct transcriptional regulation of Tab HLH27-A1 involved diverse interacting factors such as Ta ABI3-D1 and Tab ZIP62-D1.Natural variations of Tab HLH27-A1influence its transcriptional responses to drought stress,with Tab HLH27-A1^(Hap-II)associated with stronger drought tolerance,larger root system,more spikelets,and higher WUE in wheat.Significantly,the excellent Tab HLH27-A1^(Hap-II)was selected during the breeding process in China,and introgression of Tab HLH27-A1^(Hap-II)allele improved drought tolerance and grain yield,especially under water-limited conditions.Our study highlights Tab HLH27-A1's role in balancing root growth and drought tolerance,providing a genetic manipulation locus for enhancing WUE in wheat.
基金
supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA24010204)
National Key Research and Development Program of China(2021YFD1201500)
Hebei Natural Science Foundation(C2021205013)
Full-time introduction of high-end talent research project(2020HBQZYC004)
the National Natural Sciences Foundation of China(32100492,U22A6009,32072004)
Beijing Natural Science Foundation Outstanding Youth Project(JQ23026)
the Major Basic Research Program of Shandong Natural Science Foundation(ZR2019ZD15)
the Seed Science and Technology Innovation Team Project of Shijiazhuang(232490472A).
作者简介
Dongzhi Wang,contributed equally to this work;Xiuxiu Zhang,contributed equally to this work;Yuan Cao,contributed equally to this work;Correspondences:Dongzhi Wang,wangdongzhi1990@163.com;Correspondences:Wan Teng,tengwan@genetics.ac.cn;Correspondences:Xigang Liu,xgliu@hebtu.edu.cn;Correspondences:Jun Xiao,jxiao@genetics.ac.cn,Dr.Xiao is fully responsible for the distributions of all materials associated with this article。
