一个水稻长护颖基因的遗传分析

Genetic analysis of long sterile lemma gene in rice

为进一步弄清水稻花器官发育的分子机理,本试验对从美国引进的水稻资源中发现的1份长护颖材料(暂时命名为Y93)的表型、遗传和基因定位进行研究。表型鉴定结果显示,在正常生长条件下,Y93表现为护颖发育异常,护颖长度明显大于颖壳长度,而千粒质量和糙米率极显著低于正常护颖品种9311。Y93与9311杂交,正反交F1均表现为正常护颖长度,F2出现护颖长度分离,长护颖植株与正常长度护颖植株比例为262∶803=1∶3.06(χ2=0.09<P0.05=3.84),符合1∶3的孟德尔分离比,表明Y93的长护颖性状呈隐性单基因遗传。以Y93×9311 F2的262株隐性单株为定位群体,采用BSA(Bulked segregation analysis,BSA)法,将Y93长护颖基因(暂时命名为lsl)初步定位于水稻第7染色体上分子标记RM5344与RM3325之间,该基因与2个标记间的遗传距离分别为0.38 cM和2.10 cM。基因组测序分析结果表明,lsl可能为已发现的长护颖G1基因的1个新等位基因。

To better understand the molecular mechanism of rice floral organ development, the phenotype, heredityand gene mapping of a long lemma rice variety （tentatively named Y93）, were studied. Under normal growing condition,the material Y93 exhibited developing abnormalities of sterile lemmas, sterile lemma significantly longer than the length ofpalea, but 1 000-grain weight and brown rice rate mucher lower than the normal lemma variety 9311. The F1 of Y93 and9311 displayed normal sterile lemmas, similar to 9311, while F2 population appeared lemma length segregation with the ra-tio of long sterile lemma plants to normal plants of 1 颐3.06（字2 = 0.09〈P0.05 = 3.84）. These confirmed that long sterilelemma in Y93 was controlled by a single recessive gene. Using the F2 as mapping population, the long sterile lemma genein Y93 named lsl was mapped on chromosome seven between simple sequence repeat（SSR） marker RM5344 and RM3325by bulked segregation analysis （BSA）, and the genetic distances were 0.38 cM and 2.10 cM, respectively. Genome se-quencing showed that lsl might be a new allelic gene of theknown long sterile lemma G1 gene.