Evaluation of physicochemical characteristics and genetic diversity of widely consumed rice varieties in Kyaukse area, Myanmar

Abstract

Consumer preferences are greatly influenced by eating and cooking qualities of rice grains, along with the economic value of a specific rice variety. This study was to evaluate ten rice varieties including the check variety IR64 on their physicochemical, cooking and eating qualities as well as to identify their genetic diversity using SSR markers. Most rice varieties are medium-grain types based on length-breadth ratio, whereas the famous Myanmar rice variety, Paw San Bay Kyar, (PSBK) is bold. PSBK showed the best cooking and eating quality traits with intermediate amylose content (AC), intermediate gelatinization temperature (GT), soft gel consistency (GC), and the highest elongation ratio among the studied rice varieties. Seventeen SSR markers linked with cooking and eating traits were used to assess the extent of polymorphism and genetic variation among ten rice varieties. There were 49 alleles in total, with an average of 2.88 alleles per locus. RM592 had the maximum number of alleles. The average PIC value ranged from 0.22 (RM540) to 0.77 (RM592). Cluster analysis with UPGMA method based on Jaccard’s similarity coefficient divided ten rice varieties into two main groups and four sub-clusters. In multiple regression analysis, RM190 and Wx primers were discovered to be significantly associated with AC, GC and GT of cooking and eating quality traits. This study could contribute to the choice of rice varieties with superior cooking and eating qualities for rice breeding programs by implementing physicochemical characteristics and molecular analysis.