特早熟陆地棉纤维品质性状的QTL分析

QTL Analysis of Fiber-related Traits in Upland Cotton of Special Early Mature

利用SSR标记对(石K5×新陆早24号)F2群体进行了遗传连锁图谱的构建,并利用(石K5×新陆早24号)F2:3家系进行了纤维相关性状QTL的定位。研究结果表明:①F2:3家系的纤维相关性状呈现多基因控制的遗传特点,衣分、麦克隆值存在超亲分离。衣分与上半部平均长度、整齐度存在负相关,与麦克隆值、断裂比强度、伸长率之间存在正相关,但相关性均不显著。②在两亲本间筛选了2 100对棉花SSR引物,共选出多态性明显且重复性好的50对SSR引物。利用陆地棉品种间杂交(石K5×新陆早24号)F2群体,对50个标记位点进行遗传连锁分析,初步构建了一个包括12个连锁群,34个标记,标记间平均间距18.11 cm,全长615.9 cm的陆地棉和陆地棉的分子标记遗传连锁图,该图约覆盖棉花基因组的12.32%。③复合区间作图,检测到1个衣分QTL,解释衣分变异的76.93%;1个断裂比强度QTL,能解释断裂比强度变异的30.82%;1个麦克隆值QTL,能解释麦克隆值变异的13.57%。

In this study, a genetic linkage map was constructed with SSR markers using 178 F2 plantsdeveloped from a cross between upland cotton cultivar xinluzao24 and SkS. The present genetic linkage map was used to identify and map the quantitative trait loci （QTL） affecting fiber-related traits in F2：3 family lines. The mainly results were as following ：（1） The F2：3 family of fiber-related traits with multiple genes to the genetic characteristics, lint, micronaire value was extremely isolated. Lint and the first half of the average length uniformity negatively correlated with micronaire, fracture strength, Elongation between correlated, but the correlation was not significant. （2） A total of 50 polymorphism primer pairs were found among a total of 2100 cotton SSR primer pairs and a total of 50 loci were employed to perform linkage analysis using the intraspecific population （xinluzao 24 ×SKS） F2of upland cotton. 34 markers were distributed into 12 linkage groups, while 16 markers remained unlinked. The linkage map covered 615.9 cm or approximately 12.32% of the total recombination length of the cotton genome. The linkage groups with the average distance about 18.11 cm between two markers. （3） Based on composite interval mapping, one QTL was identified for lint percent, explaining 76.93% of the lint percent variance. One QTL for fiber strength were identified, explaining 30.82% of the fiber strength variance. One QTL for Micronaire were identified, explaining 13. 57% of the Micronaire variance.