小麦品种冀麦24抗麦红吸浆虫QTL分析

麦红吸浆虫是影响小麦产量和品质的重要害虫,研究小麦对吸浆虫抗性的遗传及其连锁分子标记对于提高抗虫品种的选择效率具有重要意义。本研究以小麦感虫品系6218与抗虫品种冀麦24产生的重组近交系(RIL)群体为材料,利用SSR标记和人工虫圃对冀麦24的抗虫性遗传进行了研究。结果表明:6218与冀麦24的抗性差异显著,RIL群体在2年2点的鉴定中抗性稳定;所构建的遗传连锁图谱包含112个SSR位点,形成26个连锁群,图谱全长835.7 cM,标记间平均距离为7.5 cM。利用QTL IciMapping的完备区间作图法,在4A染色体上检测到1个加性效应位点(QSm.hbau-4A),该位点在2个鉴定年度的贡献率分别为9.67%、10.57%。该抗性QTL及其连锁SSR标记的发掘,将有助于提高小麦抗吸浆虫育种的选择效率。

QTL Analysis for Midge Resistance in Wheat Cultivar Jimai 24

Wheat blossom midge(Sitodiplosis mosellana Gehin)is one of the most important pests in wheat, which has caused large losses for wheat production and grain quality. Genetic analysis of wheat resistance to midge based on Quantitative trait locus (QTL) mapping and linked markers has important implications for improving the selection efficiency in breeding midge-resistant wheat. In this study, with recombinant inbred lines(RILs) derived from susceptible and resistant wheat lines as materials, we mapped the QTLs of midge resistance and characterized the relevant inheritance in Wheat cultivar Jimai 24 by using SSR markers and artificial midge nursery. The results showed that resistance between lines 6218 and Jimai 24 are significantly different, and resistance scales among RIL lines are stable during two consecutive years. A linkage map was constructed with 124 SSR loci, which comprises 24 linkage groups. The total length of this map was 672.8cM, and the average distance among different markers was 6.6cM. Using the IciMapping package for inclusive composite interval QTLmapping QTL, a QTL(QSm.hbau-4A) with additive effects was identified on 4A chromosome. The phenotypic variance explained (PVE) of this locus in the two test years is 9.67% and 10.57%, respectively. The mapping of this QTL and the identification of its linked SSR markers will increase the selection efficiency for breeding midge-resistant lines or cultivars.