The inheritance of days to flowering in broccoli (Brassica oleracea var. italica)

Summary

Crosses between an early flowering inbred broccoli (Brassica oleracea L. var. italica) HS140 and four later maturing inbred lines, S301, S310, s318, and S258, were studied to determine the inheritance of earliness as expressed by days to first open flower. Mean days to first flower for F₁ and F₂ were almost identical, and were close to the mean of the two parents in three crosses, indicating additive inheritance. In the cross HS140×S258, for which no F₁ plants were available, the F₂ mean was closer to the mean of the early parent, but this was likely due to a distortion of the data caused by the very late maturation of S258, the latest maturing parent in the study. Frequency distribution for parents and progenies supported the conclusions from parent and progeny mean values and indicated that days to maturity is a quantitative character, with mostly additive inheritance.