Genetic inheritance and identification of molecular markers linked to male sterility in African marigold (Tagetes erecta L.)

The demand for hybrid varieties of African marigold ( Tagetes erecta L.) is on the rise due to the increased productivity and uniformity exhibited by F ₁ hybrids. To simplify the hybridization process, the use of a male sterile line is essential, as emasculation can be complicated due to the unique flower structure of marigold. In this study, seed-propagated petaloid male sterile lines with a genetic inheritance were employed. The inheritance of sterility was investigated across six generations (P ₁ , P ₂ , F ₁ , F ₂ , BC ₁ and BC ₂ ) and confirmed a single dominant gene governing petaloid male sterility over multiple seasons. The identification of molecular markers closely linked to the male sterility locus is crucial for accurately identifying genotypes with the desired traits within breeding populations. The marker CPSSR-39 exhibited clear and consistent segregation, following a Mendelian 1:1 ratio in accordance with the genes governing petaloid male sterility. This study represents the first report of genic petaloid male sterility and demonstrates the validation of linked markers, highlighting the potential use of CPSSR-39 in marker-assisted selection in marigold. This breakthrough opens up numerous opportunities for the commercial hybrid seed production of marigold, marking a significant advancement in marigold breeding.