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.

ABSTRACT In maize, sex is determined by the formation of staminate and pistillate florets from an initially bisexual floral meristem through action of <italic>Silkless1</italic> (<italic>Sk1</italic>), <italic>Tasselseed1</italic> (<italic>Ts1</italic>) and <italic>Tasselseed2</italic> (<italic>Ts2</italic>) genes. In this study, separate temperate donors having mutant <italic>sk1</italic> (EC904829 and EC904831), <italic>ts1</italic> (EC904827) and <italic>ts2</italic> (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 <italic>sk1</italic>, <italic>ts1</italic> and <italic>ts2</italic> genes was established in a standard Mendelian principles in both monohybrid and dihybrid crosses irrespective of genetic background. About 444 F2 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 <italic>sk1</italic> with two <italic>ts</italic> mutations (<italic>ts1</italic> and <italic>ts2</italic>). No progeny with both silkless and tasselseed phenotype was observed. The double mutants (<italic>sk1sk1</italic>/<italic>ts1ts1</italic> and <italic>sk1sk1</italic>/<italic>ts2ts2</italic>) were identified through progeny testing. Our study emphasize the untapped potential of these mutants, providing a renewed focus for maize breeders worldwide. [ABSTRACT FROM AUTHOR]