Molecular Mechanisms of Male Sterility in Maize

Maize (Zea mays) represents one of the most successful uses of heterosis among crops. Hybrid maize seeds can be produced by crossing a male-sterile female parent with a male parent as the pollen donor to achieve high seed purity at low cost. Cytoplasmic male sterility (CMS) has been widely used for maize hybrid seed production. Recently, several hybrid seed production technologies based on genic male sterility (GMS) genes have been developed. In addition, the identification of environment-sensitive genic male sterility (EGMS) genes provides opportunities for the two-line system to be applied in maize hybrid seed production. In this review, we systematically summarize the male-sterile genes and molecular mechanisms of male sterility in maize. Future prospects for the study of maize male sterility are highlighted. Future research will enhance our understanding of the molecular regulatory networks of male sterility and promote the process of maize hybrid seed production using male sterile lines.