普通野生稻稻米加工品质和外观品质性状QTL定位

本研究利用一套以籼稻品种“特青”为遗传背景的云南元江普通野生稻（Oryza rufipogon Griff.）渗入系为材料，采用单标记回归分析和渗入片段叠代法，对出糙率、整精米率、垩白粒率、垩白度、长宽比等5个品质性状的QTL进行了分析，初步定位了16个QTL，有10个QTL来自野生稻的等位基因能改良群体的品质性状。在第5染色体RM289附近检测到了同时影响长宽比、垩白粒率QTL，来自野生稻的等位基因能增加长宽比、降低垩白粒率，贡献率也较高。在第8染色体RM152附近检测到降低垩白粒率和垩白度的QTL，其贡献率分别为14％和9%。本研究结果不仅为品质性状分子标记辅助选择提供参考，而且充分显示了利用野生稻的优异基因改良栽培稻品质性状的巨大潜力。

Identification of QTLs Associated with Processing Quality and Appearance Quality of Common Wild Rice (Oryza rufipogon Griff.)

The objective of this study is to identify and exploit quantitative loci (QTLs) associated with grain quality from common wild rice(O. rufipogon Griff.). Using single-point analysis and chromosomal segment substitution methods, a total of 16 QTLs for 5 traits related to grain quality, including percent of brown rice, percent of head rice, percent of chalky grain, white core area and length width ratio, were detected using an introgression line population of Chinese common wild rice from Yuanjiang, Yunnan Province, with the background of indica cultivar (O.sativa L.) Teqing. Of 16 the QTLs detected in this study, the O. rufipogon-derived alleles of 10 QTLs contributed a desirable effect on Teqing background. One locus near SSR marker RM598 on chromosome 5 influencing both percent of chalky grain and length width ratio of rice grain was found and the allele from common wild rice increased grain length width ratio and decreased percent of chalky grain. One QTL for percent of chalky grain and white core area, explaining 14% and 9% of the phenotypic variance respectively, was detected near RM152 on chromosome 8 and the O. rufipogon-derived allele decreased percent of chalky grain and white core area. The results presented here might be useful in improvement of rice grain quality by marker-assisted selection and was also suggested that there was enormous potential for improving grain quality of cultivated rice utilizing the favorable genes of wild species in rice breeding program.