Transcriptome-based analysis of key pathways relating to yield formation stage of foxtail millet under different drought stress conditions

Jing Wang; Zexin Sun; Xinning Wang; Ying Tang; Xinyi Li; Chuanyou Ren; Jingyao Ren; Xiaoguang Wang; Chunji Jiang; Chao Zhong; Shuli Zhao; He Zhang; Xibo Liu; Shuli Kang; Xinhua Zhao; Haiqiu Yu

doi:10.3389/fpls.2022.1110910

Transcriptome-based analysis of key pathways relating to yield formation stage of foxtail millet under different drought stress conditions

Front Plant Sci. 2023 Feb 3:13:1110910. doi: 10.3389/fpls.2022.1110910. eCollection 2022.

Authors

Jing Wang¹, Zexin Sun¹, Xinning Wang¹, Ying Tang¹, Xinyi Li¹, Chuanyou Ren¹, Jingyao Ren¹, Xiaoguang Wang¹, Chunji Jiang¹, Chao Zhong¹, Shuli Zhao¹, He Zhang¹, Xibo Liu¹, Shuli Kang¹, Xinhua Zhao¹, Haiqiu Yu¹

Affiliation

¹ College of Agronomy, Shenyang Agricultural University, Shenyang, China.

Abstract

Although foxtail millet, as small Panicoid crop, is of drought resilient, drought stress has a significant effect on panicle of foxtail millet at the yield formation stage. In this study, the changes of panicle morphology, photosynthesis, antioxidant protective enzyme system, reactive oxygen species (ROS) system, and osmotic regulatory substance and RNA-seq of functional leaves under light drought stress (LD), heavy drought stress (HD), light drought control (LDCK) and heavy drought control (HDCK) were studied to get a snap-shot of specific panicle morphological changes, physiological responses and related molecular mechanisms. The results showed that the length and weight of panicle had decreased, but with increased empty abortive rate, and then yield dropped off 14.9% and 36.9%, respectively. The photosynthesis of millet was significantly decreased, like net photosynthesis rate, stomatal conductance and transpiration rate, especially under HD treatment with reluctant recovery from rehydration. Under LD and HD treatment, the peroxidase (POD) was increased by 34% and 14% and the same as H₂O₂ by 34.7% and 17.2% compared with LDCK and HDCK. The ability to produce and inhibit O^2- free radicals under LD treatment was higher than HD. The content of soluble sugar was higher under LD treatment but the proline was higher under HD treatment. Through RNA-seq analysis, there were 2,393 and 3,078 different genes expressed under LD and HD treatment. According to the correlation analysis between weighted gene coexpression network analysis (WGCNA) and physiological traits, the co-expression network of several modules with high correlation was constructed, and some hub genes of millet in response to drought stress were found. The expression changes relating to carbon fixation, sucrose and starch synthesis, lignin synthesis, gibberellin synthesis, and proline synthesis of millet were specifically analyzed. These findings provide a full perspective on how drought affects the yield formation of foxtail millet by constructing one work model thereby providing theoretical foundation for hub genes exploration and drought resistance breeding of foxtail millet.

Keywords: DEGs; RNA-seq; drought stress; foxtail millet; physiological index; yield formation.

Grants and funding

This work was supported by the National Key Research and Development Program of China (2019YFD1002204); Shenyang Agricultural University introduced talent research project (20153042).