中文摘要：

为了探明粒宽基因GW5对水稻粒形的作用,本研究利用DNA序列分析技术和PCR技术,对已测序的稻属野生种、水稻微核心种质以及2007-2013年江苏省审定的粳稻品种中GW5的变异类型进行了鉴定。研究结果表明,野生稻都含有GW5基因的1212-bp序列,但DNA序列有着明显的分化。在水稻微核心种质的籼粳亚种中,相对于GW5插入型（Ins）而言,缺失型（Del）水稻品种有着较短的粒长、较宽的粒宽、较厚的粒厚、较小的长宽比和较重的千粒质量,并且GW5基因的变异对籼亚种的粒形和千粒质量的影响均达到极显著水平。江苏省近年审定的绝大部分粳稻品种中GW5基因为缺失型。GW5基因的1212-bp Indel变异对水稻粒形和千粒质量有着不同程度的影响,这些研究结果对利用GW5的等位基因进行水稻育种有着重要的指导价值。

英文摘要：

To explore the effect of grain width gene GW5 on rice grain shape,the analysis of genomic DNA sequence and PCR were conducted in sequenced wild species of genus Oryza,rice mini core collection （ RMCC） and certificated ja-ponica varieties in Jiangsu province from 2007 to 2013. We found that GW5 involved 1212-bp seuqence in the wild rices. The phylogeny demonstrated an apparent differentiation on DNA sequence of GW5 among these species. In the RMCC,rice varieties with the Del genotype of GW5 had shorter grain length,wider grain width,thicker grain thickness,smaller ratio of length to width and larger 1000-grain weight, as compared with the ones of the Ins genotype. And very significant differ-ences in the grain shape and 1000-grain weight were found in the Indica subspecies. Subsequently,the rice of Del genotype of GW5 was detected in the vast majority of japonica varieties certificated in Jiangsu province. There are different effects of GW5 related 1212-bp Indel allelic variation on rice grain shape and 1000-grain weight,which will pay the way to utilize the al-lelic variations of gene GW5 in the rice yield breeding program.