Mapping and validation of microsatellite markers linked to sugary1 and shrunken2 genes in maize (Zea mays L.)

摘要

Sweet corn has emerged as one of the popular choices as fresh and processed vegetables, worldwide. Two genes namely, sugary] (su1) and shrunken2 (sh2) that cause significant increase in sugar levels of endosperm, have been extensively used in sweet corn cultivar development. In order to identify and validate microsatellite/SSR markers linked to su1 and sh2, F-2 mapping populations were generated between wild type and mutant (sugary or shrunken) genotypes. Bulk segregant analysis (BSA) in three mapping populations mapped su1 on short arm of chromosome 4 (bin. 4.05), while sh2 could be located on long arm of chromosome 3 (bin 3.08) using two mapping populations. The analysis identified seven linked SSR markers for su1 and four SSR markers linked to sh2. Across populations, umc2061 was identified as the nearest marker from su1 with genetic distance of 0.3, 0.6 and 1.6 cM, while umc2276 could be located at 1.2 and 1.5 cM from sh2. These two markers can be effectively utilized in marker-assisted selection of sweet corn trait.