Acknowledgments
This research was supported by the National Natural Science Foundation of China (4210071364), the Ministerial and Provincial Co-Innovation CentreĀ forĀ Endemic Crops Production with High-quality and Efficiency in Loess Plateau, Taigu 030801, China (SBGJXTZXKF-02), the National Key Research and Development Program of China (2018YFE0112300 and 2018YFD0200408). We wish to thank the editors and reviewers for their constructive comments.