improving the internode diameter and breaking strength of glutinous rice genotypes as nk2, ck92 and ck2003

Abstract

To enhance lodging resistance through increasing the stem stiffness of sticky rice, three single crosses were performed between three sticky rice genotypes as NK2, CK92 and CK2003 (O. sativa sp. indica) and Japanese rice genotype (O. sativa sp. japonica). Progenies were selected from F1 to F4 segregant populations of each single cross. Accordingly, internode diameter and breaking strength were assessed as two target traits. The results showed that the internode diameter and breaking strength of segregants had been improved significantly. From F4 generation, eight selected lines were noticed with the average diameter of first, second, third and fourth internodes varied 2.23- 2.67, 3.47-4.27, 4.83-5.20, and 5.80-6.30 mm, respectively. The breaking strength of first, second, third and fourth internodes was varied in the ranges of 2.05-3.26, 5.54-6.60, 8.77-10.16, and 13.79-14.76 N/cm2 , respectively. The promising lines expressed their larger diameter and better breaking strength as compared to their parents. They would be tested under field condition before releasing.