Endosperm sugar accumulation caused by mutation of PHS8/ISA1 leads to pre‐harvest sprouting in rice

• DOI: 10.1111/tpj.13970
• Publication Date: 2018-05-18T20:40:02Z
• Authors: Lin Du; Fan Xu; Jun Fang; Shaopei Gao; Jiuyou Tang; Shuang Fang; Hongru Wang; Hongning Tong; Fengxia Zhang; Jinfang Chu; Guodong Wang; Chengcai Chu
• Keywords: Sprouting

Summary Pre‐harvest sprouting ( PHS ) is an unfavorable trait in cereal crops that could seriously decrease grain yield and quality. Although some ‐associated quantitative loci or genes cereals have been reported, the molecular mechanism underlying remains largely elusive. Here, we characterized a rice mutant, phs8 , which exhibits phenotype accompanied by sugary endosperm. Map‐based cloning revealed 8 encodes starch debranching enzyme named isoamylase1. Mutation resulted phytoglycogen breakdown sugar accumulation Intriguingly, with increase of contents, decreased expression Os ABI 3 5 as well reduced sensitivity to abscisic acid ABA were found mutant. Using suspension cell system, confirmed exogenous sufficient suppress both . Furthermore, overexpression partially rescue Therefore, our study presents important evidence supporting endosperm not only acts essential energy source for seed germination but also determines dormancy affecting signaling.