Analysis of waxy proteins in Chinese winter wheat cultivars using SDS-PAGE and molecular markers

Chino. 利用SDS-PAGE分析了国内外306份小麦品种（系）Waxy蛋白的缺失类型，筛选出缺失Wx-B1蛋白亚基的材料46份；通过对济麦19×豫麦47的120个F2单株Waxy蛋白亚基分析，发现缺失Wx-B1的比例接近1/4，符合孟德尔分离规律。利用3个STS标记和1个SSR标记对不同Waxy蛋白缺失类型进行鉴定，验证其在分子标记辅助育种中的有效性。结果表明，Wx-7A位点的STS引物在野生型中扩增出1条1 172 bp的特异带，而缺失Wx-A1蛋白亚基的突变材料中没有扩增出该特异带；Wx-4A位点的STS引物在野生型中扩增出1条440 bp的特异带，缺失Wx-B1蛋白亚基的突变材料中没有该扩增片段；Wx-7D位点的STS引物在野生型中扩增出1条940 bp的特异带，而在缺失Wx-D1蛋白亚基的突变材料中则扩增出1条360 bp的特异带；Wx-7D位点的SSR引物在野生型中扩增出1条204 bp的特异带，在缺失Wx-D1蛋白亚基的突变材料中没有扩增出该特异带。这4个标记可以用于分子标记辅助育种。

Inglés. A total of 306 wheat cultivars and advanced lines from China, US and Australia were screened for the Waxy protein by SDS-PAGE. The results indicated that 46 of these cultivars were the null Wx-B1 type. The proportion of individuals with null Wx-B1 in 120 F2 progenies derived from the Jimai19×Yumai47 was 1/4 approximately, in accordance with the theoretical ratio. Three STS and 1 SSR markers were used to analyze the wheat cultivars with different types of Waxy proteins. Validation of the markers was carried out for the detection of Wx-7A, Wx-4A and Wx-7D genes. The results indicated that a 1172 bp-fragment was amplified with Wx-7A specific STS marker from the wild genotypes, while the fragment was absent for the mutant with null Wx-A1; a 440 bp-fragment was detected with Wx-4A specific STS marker from the wild genotypes, whereas, the fragment was absent for the mutant with null Wx-B1; a 940 bp-fragment was amplified with Wx-7D specific STS marker from the wild genotypes, and a 360 bp-fragment was found for the mutant such as ‘Baihuomai’ with null Wx-D1; and a 204 bp-fragment was detected with Wx-7D specific SSR marker from the wild genotypes, while the fragment was absent for the mutant with null Wx-D1. These markers are useful tools to identify wheat cultivars with mutant and normal alleles of the Waxy genes in marker-assisted selection of wheat breeding programme.