小麦产量相关性状的全基因组关联分析

为挖掘小麦产量相关性状的优异等位变异,利用筛选的106对多态性SSR标记扫描236份小麦种质资源组成的自然群体,并进行遗传多样性分析。结果表明,利用106对引物共检测到874个等位变异,每对引物平均为8.24个,变化范围为2～23个;主要等位变异频率的变化范围为0.177～0.987,平均为0.545;多态性信息指数(PIC)的变化范围0.026～0.895,平均0.550。采用混合线性模型对4个环境的株高、穗长、主穗粒数、单株穗数和千粒重进行关联分析后,共关联到20对SSR标记,有26个显著关联位点(P0.01),其表型解释率范围为6.25%～18.97%。其中,标记 Xgwm164(1A)在4个环境下均与株高显著关联;Xgwm55(6D)同时与株高和穗长两个性状显著关联; Xwmc415(5B)在2个环境下与单株穗数显著关联。通过对等位变异表型效应的解析筛选出各关联位点的优异等位变异,包括可以降低株高4.24cm的优异等位变异 Xgwm164-1A_(118)、可以增加穗长0.75cm的优异等位变异 Xgwm429-2B_(207)、可以增加单株穗数1.07个的优异等位变异 Xwmc415-5B_(154)、可以增加主穗粒数1.93粒的优异等位变异 Xgwm232-1D_(138)及可以增加千粒重0.92g的优异等位变异 Xgwm610-4A_(170)。

Genome-Wide Association Analysis of Yield-Related Traits in Wheat

To explore the excellent allelic variation for yield-related traits in wheat, in this study,a natural population consisting of 236 wheat germplasm resources was scanned by 106 pairs of polymorphic SSR markers and its genetic diversity was analyzed. The results showed that a total of 874 allelic variations were detected by the 106 pairs of primers, with an average of 8.24, ranging from 2 to 23; the major allelic variation frequency ranged from 0.177 to 0.987, with an average of 0.545; the polymorphism information content(PIC) varies from 0.026 to 0.895 with an average of 0.550. The mixed linear model was used to analyze the plant height, spike length, spikelet number per spike, kernel number per spike,and thousand kernel weight in four environments, which were correlated with 20 pairs of SSR markers with significant associations at 26 loci(P<0.01). The phenotypic interpretation rate ranged from 6.25% to 18.97%, and the marker Xgwm164(1A) was significantly associated with plant height in all four environments; Xgwm55 (6D) was significantly associated with both plant height and spike length; Xwmc415(5B) was significantly associated with spikelet number per spike in two environments. Through the analysis on the phenotypic effect of allelic variation, the excellent allelic variation of each related locus was screened, including the excellent allelic variation Xgwm164-1A₁₁₈ which can reduce plant height by 4.24 cm; the excellent allelic variation Xgwm429-2B₂₀₇ can increase the length of the spike by 0.75 cm; the excellent allelic variation Xwmc415-5B₁₅₄ can increase the spikelet number per spike by 1.07; the excellent allelic variation Xgwm232-1D₁₃₈ can increase the number of main spikes by 1.93; and the excellent allelic variation Xgwm610-4A₁₇₀ can increase 1 000-grain weight by 0.92 g.