穗发芽抗性STS标记Vp1B3在中国小麦微核心种质中的检测

Detection of a Viviparous-1 STS Marker for Pre-harvest Sprouting Tolerance in Mini-core Collections of Chinese Wheat Varieties

小麦在临近收获前发生穗发芽,不仅劣化小麦加工品质,而且降低小麦产量。提高小麦穗发芽抗性水平是小麦育种工作的重要目标之一。本实验以258份中国小麦微核心种质为试材,利用已报道的小麦穗发芽抗性标记Vp1B3对其进行多态性检测,以了解该抗性标记在中国小麦微核心种质中的分布规律,寻找新的等位变异类型,并结合部分品种的发芽指数,分析不同等位变异类型与穗发芽抗性之间的关系。结果表明:检测的258份供试材料中,a带型(13.9%)、c带型(41.1%)和e带型(34.5%)等3种带型为主要扩增带型,占总变异类型的89.5%;b、d、f带型为本研究所发现的新的等位变异类型,占总变异类型的2.4%。此外,杂合带型以及无扩增产物的分别占总变异类型的3.5%和4.6%。对选取的部分穗发芽抗性不同的材料进行统计分析,结果显示,c带型品种的发芽指数(GI,47.9%)明显高于a带型(GI,22.6%)和e带型(GI,24.3%)的品种,但c带型的品种中也存在GI值较低的高抗穗发芽品种,而a带型和e带型的品种中同时也出现了GI值较高的感穗发芽品种,说明小麦穗发芽的遗传机制比较复杂,其抗性不仅仅受Vp1B3基因控制,而是多种因素共同作用的结果。

Wheat pre-harvest sprouting （PHS） can cause significant reduction in yield and end-use quality. Increasing PHS tolerance is one of the most important tasks in wheat breeding. In this study, the frequencies of polymorphic fragments of STS marker, Vp1B3, was analyzed using a total of 258 mini-core collections of Chinese wheat varieties. Moreover, the relationship between the polymorphic fragments of Vp1B3 and PHS tolerance was also evaluated in 45 wheat varieties selected from above 258 wheat mini-core collections. The results show： among the 258 genotypes tested, 89.5% wheat varieties were amplified the same fragment a （13.9%）, c （41.1%）, e （34.5%） as previous investigation and 2.4% varieties were new polymorphic fragments which were found as b, d, f fragment. Statistical analysis indicated that a, c and e fragment had average germination indexes （GI） of 22.6%, 47.9%, and 24.3% in 45 wheat germplasm selected, respectively. The varieties which can be amplified a or e fragments were more PHS resistance than the varieties which can be amplified c fragments. However, there were also some varieties with c fragments that were low GI and some varieties with a or e fragments that were high GI, which suggested wheat pre-harvest sprouting was influenced by many environmental factors and dormancy-related genes together.