Genetic Evidence of Recessive Epistasis Among Sex Determining silkless1 ( sk1 ) tasselseed1 ( ts1 ) and tasselseed2 ( ts2 ) Genes and Its Utility in Maize ( Zea mays L.) Breeding

In maize, sex is determined by the formation of staminate and pistillate florets from an initially bisexual floral meristem through action of Silkless1 ( Sk1 ), Tasselseed1 ( Ts1 ) and Tasselseed2 ( Ts2 ) genes. In this study, separate temperate donors having mutant sk1 (EC904829 and EC904831), ts1 (EC904827) and ts2 (EC904824) genes were crossed with sub‐tropical inbreds (HKI323 and HKI1105) to investigate the genetics and interaction of silkless and tasselseed traits. The monogenic and nuclear inheritance of sk1 , ts1 and ts2 genes was established in a standard Mendelian principles in both monohybrid and dihybrid crosses irrespective of genetic background. About 444 F 2 progenies across digenic population ‐A, ‐B and ‐C segregated as 239 normal: 109 silkless: 96 tasselseed, and 377 progenies of digenic populations ‐D, ‐E and ‐F segregated with 214 normal: 79 silkless: 84 tasselseed plants revealing recessive epistatic interaction (9:3:4) of sk1 with two ts mutations ( ts1 and ts2 ). No progeny with both silkless and tasselseed phenotype was observed. The double mutants ( sk1sk1 / ts1ts1 and sk1sk1 / ts2ts2 ) were identified through progeny testing. Our study emphasize the untapped potential of these mutants, providing a renewed focus for maize breeders worldwide.