Waterlogging Priming Enhances Hypoxia Stress Tolerance of Wheat Offspring Plants by Regulating Root Phenotypic and Physiological Adaption

With global climate change, waterlogging stress is becoming more frequent. Waterlogging stress inhibits root growth and physiological metabolism, which ultimately leads to yield loss in wheat. Waterlogging priming has been proven to effectively enhance waterlogging tolerance in wheat. However, it is not known whether waterlogging priming can improve the offspring's waterlogging resistance. Here, wheat seeds that applied waterlogging priming for one generation, two generations and three generations are separately used to test the hypoxia stress tolerance in wheat, and the physiological mechanisms are evaluated. Results found that progeny of primed plants showed higher plant biomass by enhancing the net photosynthetic rate and antioxidant enzyme activity. Consequently, more sugars are transported to roots, providing a metabolic substrate for anaerobic respiration and producing more ATP to maintain the root growth in the progeny of primed plants compared with non-primed plants. Furthermore, primed plants' offspring promote ethylene biosynthesis and further induce the formation of a higher rate of aerenchyma in roots. This study provides a theoretical basis for improving the waterlogging tolerance of wheat.