花生叶片SPAD值与SSR分子标记的关联分析

Association Analysis of Leaf SPAD Value and SSR Markers in Peanut

叶片SPAD值能够反映作物叶片叶绿素含量。本研究鉴定了268份花生种质的叶片SPAD值,与391对多态性SSR标记进行关联分析,共检测到2 044个等位变异,单个标记等位变异数目为2~15个,平均为5.228个。MAF平均为0.617,GD平均为0.501,PIC平均为0.441。采用TASSEL v2.1软件的一般线性模型GLM(简单模型和Q模型)和混合线性模型MLM(K和Q+K模型)对叶片SPAD值进行关联定位,结果表明,Q+K模型是进行关联分析的最适宜模型。两年间共检测到28个与叶片SPAD值显著相关(p<0.01)的标记,其中15个标记相关性达极显著水平(p<0.001)。能够两年重复检测到的达到显著水平以上的标记共6个,其中达到极显著水平的4个。这4个标记共检测到18个等位变异,其中主要增效等位变异有AhTE1030-A285、AhTE0633-A394、AHGS1280-A289、AHGS1952-A233和AHGS1952-A239,典型的载体种质包括‘花17’、‘冀0212-4’、‘98D080-2’和‘千叶55’;主要减效等位变异有AhTE0633-A286、AHGS1280-A339和AHGS1952-A250,典型的载体种质包括有AH31613和‘抚宁多粒’。以上发掘出的优异等位基因及优异种质资源,可为花生分子辅助选择育种提供参考。

Leaf SPAD value can reflect chlorophyll content in crop leaves. In this study, we identified SPAD value of a total of 268 peanut lines and conducted association analysis with 391 polymorphic SSR markers. In total, 2 044 alleles were tested, and the number of alleles per marker ranged from 2 to 15, with an average of 5.228 alleles per locus. The mean value of major allele frequency（MAF）, gene diversity（GD） and polymorphism information content（PIC） were 0.627, 0.501 and 0.441, respectively. The associated location of leaf SPAD value was performed in TASSEL v2.1 using GLM（Simple and Q model） and MLM（K and Q＋K model） option. Model comparisons showed Q＋K was the most suitable model for association analysis. A total of 28 markers were detected to be significantly associated with SPAD（p〈0.01） in two years, 15 of which were detected with remarkably significant difference（p〈0.001）. Among these markers, 6 were repeatedly found at significant level in two years, 4 of which were detected at remarkably significant level. A total of 18 alleles were examined by the 4 significantly associated markers, containing 5 key positive alleles, such as AhTE1030-A285, AhTE0633-A394, AHGS1280-A289, AHGS-1952-A233 and AHGS1952-A239, and typical positive allele carriers, including‘Hua17＇,‘Ji0212-4＇,‘98 D080-2 ＇and‘Qianye55‘ were also screened out. In addition, there were three main negative alleles（AhTE0633-A286, AHGS1280-A339, AHGS1952-A250） and typical negative allele carriers（‘Funingduoli＇, AH31613）. These excellent alleles and germplasm resources could provide reference for marker-assisted selection for peanut improvement.