利用染色体单片段代换系定位水稻粒重QTL

粒重是决定水稻产量的三要素之一，是由多基因控制的数量性状。本研究以广陆矮4号为受体，日本晴为供体的119个染色体单片段代换系群体为试验材料，利用 SPSS软件分析了粒重与粒形性状之间的相关性，通过单因素方差分析和 Dunnett’s多重比较，测验单片段代换系与受体亲本广陆矮4号之间粒重的差异，以2年都能检测到的显著差异位点作为稳定表达的 QTL。结果表明：千粒重与粒长、长宽比呈极显著正相关，与粒宽、粒厚相关性不显著；以 P≤0.001为阈值，2年都能检测到的千粒重相关 QTL 19个，分布在除第10、12染色体以外的10条染色体上。其中，10个QTL的加性效应表现为增效作用，其加性效应值的变化范围为0.49~2.74 g，加性效应百分率的变化范围为2.00%~11.05%；9个 QTL加性效应表现为减效，加性效应值的变化范围为0.60~2.35 g，加性效应百分率的变化范围为2.40%~9.48%。这些QTL的鉴定，为进一步精细定位或克隆相应 QTL奠定了基础。

Mapping of QTLs Related to Grain Weight Using Chromosome Single Segment Substitution Lines in Rice

Grain weight, one of the major factors determining rice yield, is a typical quantitative trait control ed by multiple genes. With Guangluai 4 as recipient and Nipponbare as donor, a population of 119 chromosome single segment substitution lines had been developed. Correlation analysis between grain weight and grain shape by SPSS revealed that 1 000-grain weight shared extremely significant posi-tive correlation with grain length and length-width ratio, but no significant correlation with grain width and thickness. The QTL analysis of grain weight was carried out using one-way analysis of variance and Dunnett＇s test. Nineteen stable QTLs re-sponsible for grain weight were identified over two years. Al 19 QTLs were identi-fied on al chromosomes except for chromosome 10 and 12 at a significance level of P≤0.001. Among them, 10 QTLs had a positive effect and were derived from the Nipponbare al ele, the additive effect of these QTLs ranged from 0.49 to 2.74 g, and the contributions of the additive effects ranged from 2.00% to 11.05%. Another 9 QTLs had a negative effect and were al derived from Guangluai 4 al ele, the ad-ditive effect of these QTLs ranged from 0.60 to 2.35 g, and the contributions of the additive effects ranged from 2.40% to 9.84%. The results provide a basis for the fine mapping and gene cloning of novel locus associated with rice grain weight.