Hulless barley (Hordeum vulgare L. Var. Nudum Hook, f.) is a typical crop in Tibetan Plateau in China. Starch, including amylopectin and amylose, is the main storage component in hulless barley, of which amylose is in low content or even absent in the endosperm of waxy barley. The Waxy gene (Wx) located on the short arm of chromosome 7H is a key gene responsible for amylose synthesis, and also acts as a favorable gene in breeding of hulless barley. However, it is difficult to select hulless barley germplasm with Wx due to lack of effective molecular markers. This study aimed to find out molecular markers applicable in the, identification of Wx gene. A total of 150 accessions of hulless barley were primarily tested by staining endosperm with I2-KI, and four accessions (IG107028, Puebla, Huzhushuangcaoren, and APM-HC1905) were found as waxy genotypes. The amylose contents (AC) of the 150 accessions, which were measured using dual-wave length spectrophotometry method, varied from 12.4% to 38.5% with an average of 26.0%. The amylose contents of the four waxy genotypes namely IG107028, Brachvtic, Kunlun 2, and Huzhushuangcaoren, were 12.4-18.6% with an average of 16.7%. No genotype without amylase was found. We selected 51 accessions with obvious difference in AC to validate the polymorphism of four pairs of SSR markers. Primers PI and P3 showed no polymorphism among the 51 accessions, and primer P4 exhibited four types of amplified product, and the fragment size positively correlated with amylose content. The P4 primer was designed according to the sequence of Wx gene on chromosome 7H of barley. Primer P4 can be used as an effective marker for selecting waxy hulless barley cultivars.%以150份青稞品种为材料,采用碘-碘化钾染色法进行表型鉴定,筛选出含糯性基因型的4份参试材料,分别是品种IG107028、Puebla、互助双槽人和APM-HC 1905.经双波长法测定,150份参试材料的直链淀粉含量(AC)为12.4％～38.5％,平均26.0％;4份糯性参试材料的直链淀粉含量为12.4％～18.6％,平均16.7％.以直链淀粉含量差别较大的51份材料为模板,利用引物P4进行扩增,结果P4引物在51份材料中均有扩增产物出现,且随着参试材料直链淀粉含量的增大,其扩增产物的分子量有逐渐增大的趋势,Wx基因位点表现出多态性,二者呈正相关.根据带型将51份材料分成Ⅰ型、Ⅱ型、Ⅲ型和Ⅳ型,其扩增片段分子量分别为457、481、489和491 bp,各类型品种的直链淀粉含量分别为12％～27％、29％～30％、31％～35％和36％～38％.P4可作为糯性青稞品种选育的辅助选择标记.
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