The essential roles of sugar metabolism for pollen development and male fertility in plants

Sugar metabolism plays an essential role in plant male reproduction. Defects in sugar metabolism during anther and pollen development often result in genic male sterility (GMS). In this review, we summarize the recent progresses of the sugar metabolism-related GMS genes and their roles during plant anther and pollen development, including callose wall and primexine formation, intine development, pollen maturation and starch accumulation, anther dehiscence, and pollen germination and tube growth. We predict 112 putative sugar metabolic GMS genes in maize based on bioinformatics and RNA-seq analyses, and most of them have peak expression patterns during middle or late anther developmental stages. Finally, we outline the potential applications of sugar metabolic GMS genes in crop hybrid breeding and seed production. This review will deepen our understanding on sugar metabolic pathways in controlling pollen development and male fertility in plants.