Inheritance Analysis for Exserted Stigma Rate in Japonica Rice

Abstract

Rice is the main crop in China. Since the discovery and exploitation of sterile strain line, three lines of Indica hybrid rice were bred successfully; the Indica hybrid rice has made great progress in production. Compared to Indica rice, Japonica hybrid rice is hard to study because it lacks the restorer gene. The key to promoting development of hybrid Japonica rice is to improve the yields of seed production. However, the low stigma exsertion rate of Japonica CMS Line is the main cause that restricts the yield of hybrid seed production of Japonica rice. As the inheritance mechanism of the stigma exsertion is complicated and difficult to study, the related study is far from enough. In this study, Jinke DS, a sterile line with higher stigma exsertion rate, and C9083, a restorer line with lower stigma exsertion rate, were used as parents for hybrid. P₁, P₂, F₁ and F₂ were chosen as the study materials and major gene plus polygene mixed inheritance model was chosen to analyze the genetic effects. The results showed that glume-opening single exserted stigma rate was in consistence with the E-2 model, glume-closed single exserted stigma rate was in consistence with the E-0 model, glume-opening dual exserted stigma rate, glume-opening exserted stigma rate, glume-closed dual exerted stigma rate and glume-closed exserted stigma rate were in consistence with the E-1 model.