Inheritance and Molecular Marker for Flowering Time in Radish (Raphanus sativus L.)

The mixed inheritance model involving major genes and polygenes was used to analyze the inheritance of radish flowering time trait in the B1, B2, F1, and F2 generations. Our results showed that flowering time was regulated by two additive-dominant-epistatic major genes and additive-dominant-epistatic polygenes (E-0 model). The major gene heritability estimated for the B1, B2, and F2 generations was 70.48%, 82.80%, and 86.90%, respectively, while the polygene heritability estimated was 0.00, 12.58%, and 8.19%, respectively. These results suggested that the flowering time of radish was regulated by major genes, with polygenes playing only a minor role. In practice, high heritability of major genes is favorable for an efficient selection of B2 and F2 generations during radish breeding. Six hundred twenty-six SSR markers were screened between late-bolting bulk and the early bolting bulk from F2 population. A marker RSS0119 associated to the flowering time trait was obtained, which revealed a high correlation with the flowering time in the F2 population as well as in 59 radish inbred lines (83.61% and 61.02%, respectively). Our findings will be useful for breeding late-bolting varieties.