黄瓜遗传图谱构建及株高相关性状的QTL定位

 为利用分子标记辅助选择黄瓜矮生性状, 以矮生黄瓜D8 ×蔓生黄瓜J IN5的188株F^₂单株作为 作图群体, 应用ISSR和SRAP分子标记技术进行多态性筛选, 构建了含65个标记位点的遗传连锁图谱。整个图谱覆盖7个连锁群, 全长831.6 cM。标记平均间距为12.7 cM, 标记间最小遗传距离为4.8 cM, 最大遗传距离为22.3 cM。采用复合区间定位分析, 检测到控制黄瓜株高性状的QTL位点2个, 均位于第4连锁群上, 贡献率分别为13.2%和13.0%; 控制节间距的QTL位点1个, 也位于第4连锁群上; 控制第一雌花开花期的QTL位点7个, 分别位于第1、2、3、5、7连锁群上, 各QTL的贡献率在6.5%～12.5%之间。

Construction of Genetic Linkage Map and QTLs Analysis for the Related Traits of Plant Height in Cucumber

With the aim ofmolecularmarker assisted selection for the traits related to dwarfing of cucumber, 188 progenies of F₂ generation derived from a cross between the dwarf variety ‘D8’ and the vining variety‘JIN5’in the present research were screened using the molecular markers ISSR and SRAP for theirpolymorphic sites, and a genetic linkage map containing 65 polymorphic loci was constructed for identifying traits associated with the plant height of cucumber. The genetic linkage map consisted of seven linkage groups, and was, totally, 831.6 cM in length. The average distance between two neighour lociwas 12.7 cM, the minimum distance was 4.8 cM, and the maximum was 22.3 cM. Further analysis using the composite interval mapping method showed that two QTLs associated with plant heightwere sited on the linkage group 4 and each accounted for 13.2% and 13.0% on phenotyp ic variance exp lained ( PVE) , respectively, and one QTL for the average internode distance was also located in linkage group 4. Seven QTL s for the days of the first female flower flowering were located in five linkage groups, i.e., the 1 st, 2nd, 3 rd, 5 th and 7 th, each accounting for from 6.5% to 12.5% on phenotyp ic variance explained ( PVE).