作物学报2025，Vol.51Issue(12)：3144-3156,13.DOI:10.3724/SP.J.1006.2025.51056
西藏大麦SSIIa基因自然变异对淀粉组成及特性的影响
Effects of natural variation in the SSIIa gene on starch composition and pro-perties in Tibetan barley
摘要
Abstract
Barley is the world's fourth-largest cereal crop and serves as a staple food for farmers and herders in the Tibetan region of China.Starch,which accounts for 50%-70%of grain weight,is the primary component determining both yield and quality.While starch content directly influences grain weight,its structure dictates physicochemical properties and hydrolysis perform-ance,ultimately affecting processing quality and end-use applications.Soluble starch synthase IIa(SSIIa)is a key enzyme in-volved in amylopectin biosynthesis,and natural polymorphisms in its gene play a significant regulatory role in starch structure and functionality.In this study,165 Tibetan barley accessions were used to systematically investigate the effects of natural varia-tion in the SSIIa gene on starch composition and properties through molecular marker identification and starch physicochemical analysis.Two major SSIIa gene variants(designated SSIIa1 and SSIIa2)were identified in Tibetan barley.Based on sequence dif-ferences,specific molecular markers were developed for efficient genotyping,revealing a characteristic 33 bp deletion that dis-tinguishes the SSIIa2 genotype.Starch property analysis showed that,compared with SSIIa1,the SSIIa2 genotype was associated with significantly higher amylose content,a larger average diameter and greater volume proportion of type B starch granules,and a higher pasting temperature.These findings clarify the natural variation pattern of the SSIIa gene and its influence on key starch quality traits in Tibetan barley,providing valuable molecular targets and a theoretical basis for quality-oriented breeding and func-tional utilization of this important crop.关键词
西藏大麦/SSIIa/自然变异/籽粒形态/淀粉特性Key words
Tibetan barley/SSIIa/natural variation/grain morphology/starch properties引用本文复制引用
刘佳荟,祁鹏飞,魏育明,江千涛,李雨龙,王雅茹,贺宏,张云书,吴郁,曾秀丽,刘廷辉,陈国跃..西藏大麦SSIIa基因自然变异对淀粉组成及特性的影响[J].作物学报,2025,51(12):3144-3156,13.基金项目
本研究由四川省重点研发计划项目(2025YFHZ0113)资助. This study was supported by Sichuan Science and Technology Program(2025YFHZ0113). （2025YFHZ0113）
