转基因抗虫棉产量相关性状QTL的分子标记及定位

 采用亚洲棉渐渗的纤维强度突出的陆地棉优质新品系0-153与陆地棉转基因抗虫新品系sGK9708为亲本，构建了F₂及F_2∶3分离群体。利用3869对SSR引物筛选亲本，得到125对多态性引物。进一步对183个F₂群体单株分析得到150个多态性标记位点，其中100个标记位点连锁，构建20个连锁群，共覆盖660 cM，占棉花总基因组的14.67%，每个连锁群平均包含5个标记位点，标记间平均相距6.6 cM，其中13个连锁群确定了对应的染色体。利用F₂和F_2:3数据，通过复合区间作图，共检测到28个产量及相关因素的QTLs。这些控制产量性状的QTLs只存在于5个连锁群上，成簇分布。与皮棉产量性状有关的2个QTLs，均与其它多个产量相关性状的QTLs在同一个连锁区段内，增效基因遗传效应方向一致，有必要研究其在标记辅助选择中的效果。本研究没有检测到在多世代表现稳定的QTL。因此，需要培育重组自交系，进一步明确产量性状有关QTL的遗传效应。

Molecular Marker and QTL of Yield-related Traits in Transgenic Insect-resistant Cotton Varieties

The cross of sGK9708×0-153 was made, which included one parent with high fiber strength, 0-153, originating from crossing of G.hirsutum L. with G.arboreum L., and backcrossing with G.hirsutum L. as the recurrent parent, and the other commercial transgenic variety with resistance to budworm, sGK9708. A total of 3869 pair SSR primers were used to screen polymorphism among two parents and their F₁, which resulted in 150 polymorphic loci from 125 pair primers in F₂ population. Linkage test indicated that 100 loci could be mapped to 20 linkage groups, which covered a total genetic distance of 660 cM, approximately 14.67% of cotton genome. The average distance of neighbor markers was 6.6 cM. 13 linkage groups were assigned to corresponding chromosome, respectively. Based on Composite Interval Mapping (CIM) method, the result showed that 28 QTLs for fiber yield related traits were detected in F₂ and F_2∶3 populations. These QTLs of yield-related trait existed in the five linkage groups only, clustered on the same locus in different chromosomes. Two QTLs of lint yield clustered with many QTLs of other yield related traits in two different linkage group segments with same direction of genetic effects. So it is necessary to study the effect of the marker-assisted selection for the two QTLs in the future. No same QTL for the yield-related trait could be detected in different generations, which shows multiple self-crossing lines should be developed for QTL analysis of yield-related traits.