QTL Analysis of Seed Cooking Quality using RIL Population in Black Soybean

Abstract

In Korea, black soybeans are traditionally consumed after cooking with rice to supplement protein and oil which are lacking in rice. Seed cooking quality including seed traits after cooking with rice, which is important for consumers, were so far not comprehensively considered during the process of breeding. In this study, we first evaluated seed quality after cooking with rice, we tested the correlation between seed cooking quality and seed water absorption ratio, and we attempted to identify the Quantitative trait locus(QTL)/gene using two recombinant inbred line (RIL) populations, i.e., Daepung × Socheong2 and Daepung × Ilpumgeomjeong. Based on phenotype and correlation analyses, the main factors affecting the hardness of soybeans cooked with rice may differ between RIL population. In the Daepung × Socheong2 RIL population, one QTL associated with seed hardness after cooking with rice was identified on chromosome 11, and Glyma.11g049600, encoding peroxidase, is proposed as a candidate gene. In the Daepung × Ilpumgeomjeong RIL population, two QTLs associated with seed hardness after cooking with rice were identified on chromosomes 7 and 19, one QTL related to seed water absorption on chromosome 3, and Glyma.19g092600 encoding pectin methylesterase inhibitor are proposed as candidate genes. This is the first study on soybean cooking quality after cooking with rice, and the locations of four related QTLs were identified. The results will be of use for future development of high-quality black soybean varieties with high consumer preference using molecular breeding methods.