染色体单片段代换系的构建及应用于QTL精细定位

染色体片段代换系(Chromosome Segment Substitution Lines，CSSLs)，又称为代换系(Substitution lines，SLs)或导入系(Introgression lines，ILs)。只含一个代换片段的代换系，即单片段代换系(Single Segment Substitution Lines，SSSLs)是理想的代换系。单片段代换系只有代换片段与受体亲本不同，其它遗传背景与受体亲本完全一致，对代换区段中的QTL进行分析时遗传背景干扰很小，有利于QTL的分析，不少学者利用单片段代换系材料对许多QTL进行了鉴定和精细定位，并克隆了一些重要性状的QTL。本文介绍了染色体单片段代换系构建的原理和利用微卫星标记(SSR）进行单片段代换系鉴定的方法，讨论了代换系构建过程中值得注意的问题，并对用染色体单片段代换系进行QTL精细定位做了展望。

Construction of Chromosome Single Segment Subsititution Lines and QTL Fine Mapping

Chromosome Single Segment Substitution Lines(CSSSLs)are the most perfect than the substitution lines containing multiple segment. The genomic backgrounds of SSSL are almost the same as that of recipient parent except the region of segment substitution. In this paper we introduced the principle and approaches of constructing single segment substitution lines, and the methods of identifying SSSLs based on the SSR-PCR assisted selections. We also listed the some cases for mapping QTL that used SSSLs as experimental materials, which showed the advantages for identifying QTL due to little interaction between substitution region and whole genome. The problems and prospects of SSSLs QTL fine mapping and cloning have been discussed in this paper.