利用海岛棉染色体片段导入系定位衣分和籽指QTL

以染色体片段导入系IL-15-5和IL-15-5-1构建的F2和F2:3分离群体,利用SSR标记对数量性状衣分和籽指QTL进行了定位。应用复合区间作图法分析两个组合的774个F2单株和F2:3家系衣分和籽指,检测到2个衣分的QTL,1个籽指的QTL。衣分QTLqLP-15-1在两世代中都被检测到,位于相同的分子标记置信区间JESPR152～NAU3040,置信的遗传距离分别为5.40cM和3.20cM;qLP-15-2只在F2:3中被检测到,位于分子标记NAU5302～NAU2901之间,置信的遗传距离为0.08cM。籽指QTLqSI-15-1在F2和F2:3中都被检测到,分别位于分子标记NAU2814～NAU3040和JESPR152～NAU3040,置信的遗传距离分别为6.70cM和5.70cM。利用染色体片段导入系能准确地定位产量组分的QTL,为棉花产量的分子设计育种奠定基础。

Mapping QTLs for Lint Percentage and Seed Index Using Gossypium barbadense Chromosome Segment Introgression Lines

Seed index (SI) and lint percentage (LP) are very important components, and many researchers have done abundant investigation on them by using different populations. Chromosome segment introgression lines (CSIL), different from the recurrent parent in introgressed segments, are the ideal materials for QTL research and the core of the breeding by design. The F₂ and F_2:3 populations were developed from CSILs-IL-15-5 and IL-15-5-1, and used in mapping QTLs for lint percentage and seed index with SSR markers. The SI and LP characteristics of the 774 F₂ individuals and F_2:3 families were analyzed by composite interval mapping (CIM), and one QTL was detected for SI and two QTLs for LP. qSI-15-1 was located between NAU2814 and NAU3040 with confident genetic distance of 6.70 cM in the F₂ population and between NAU3040 and JESPR152 with confident genetic distance of 5.70 cM in the F_2:3 population. qLP-15-1 detected in the F₂ and F_2:3 populations was located between NAU3040 and JESPR152 with confident genetic distance of 5.40 cM and 3.20 cM respectively; qLP-15-2 was mapped between NAU5302 and NAU2901 with confident genetic distance of 0.08 cM. In conclusion, the QTLs for yield components in cotton can be mapped using CSILs and provide a base for breeding by design.