【摘要】 从⁶⁰Co辐射诱变的中花11突变体库中筛选到一个小圆粒突变体TM340,突变表型为株高降低，穗型直立，籽粒短且宽。颖壳外表皮扫描电镜结果显示，野生型细胞长度要长于突变体。通过与珍汕97B构建F₂群体，从中分别选取20株正常粒与小圆粒单株构建2个极端表型混池，连同亲本进行全基因组测序及关联分析，确定突变基因位于第5号染色体。比较测序发现突变体中srs3基因在第8外显子4 431位的碱基A缺失导致移码突变。根据该位点设计CAPS标记，检测F₂分离群体中22株小圆粒单株，发现该标记与突变表型完全连锁，证明TM340小圆粒表型是由SRS3突变产生的新的等位变异引起。更多还原

【Abstract】 A small and round grain mutant named TM340 was screened from the Zhonghua 11 mutant library induced by ⁶⁰Co radiation. TM340 was characterized by erect and dense panicles, decreased plant height and grain length but increased grain width. Scanning electron microscopy of the hull showed that the cell length of mutants was significantly decreased. By constructing F₂ population with Zhenshan 97 B, 20 plants with normal grains and small and round grains were selected respectively for bulk sequencing. Bulk segregant analysis（BSA） showed candidate region on chromosome 5. Comparative sequencing showed that there was one nucleotide deletion of 4431^th adenine in the 8^th exon of srs3 from TM340, which resulted in frameshift mutation. Designed CAPS marker according to this locus was found completely linked to the mutant phenotype in the F₂ population, which proved that the small round grain phenotype of TM340 was caused by the new allelic variation produced by the SRS3 mutation.更多还原