Molecular marker-directed development of a novel cytoplasmic male sterile line in rice

Abstract

In response to the challenge of food security in the new century, heterosis exploitation is being intensified as an effective way to increase grain yield of rice. Thus, breeding of new cytoplasmic male sterility (CMS) is necessary so as to prevent homog- enization of hybrid rice in commercial breeding programs. As the rapid development of molecular biology, molecular marker based selection can not only increase the efficiency and accuracy for breeding, but also provide us the possibility to create new CMS by genotypic identification. In this study, we devel- opedanovel CMSricebyscreeningricemalesterility- inducing cytoplasm and maintainer candidates using mitotype-specific and nuclear molecular markers, respectively. Field trials reveal that the newly bred CMS line has good general combining ability and special combining abilityfor generation of hybrid rice, which means that the molecular marker system provides us an efficient and practicable approach for development of new CMS in rice breeding programs.