Fine mapping and candidate gene identification of a new male-sterile gene Brmy1 in Chinese cabbage
Male-sterile lines are valuable for hybrid seed production in Chinese cabbage. This study identified a spontaneous male-sterile mutant, my1, from the inbred line MRTY. Cytological analysis showed that pollen abortion resulted from premature tapetal degeneration and abnormal microspore development. Genetic and transcriptome analyses indicated that the trait is controlled by a recessive gene and may involve redox regulation, hormone signaling, and pollen tube growth. Fine mapping identified BrRBOHJ, a respiratory burst oxidase gene, as the candidate gene, which regulates ROS accumulation and anther development.