Inheritance of microspore embryogenic ability in Brassica crops

Inheritance of microspore embryogenic ability in oilseed rape (Brassica nap us L.) and Chinese cabbage (Brassica campestris L. ssp. pekinensis) was exa mined by 4 x 4 diallel crosses using cultivars showing a different response . In both species, embryo yields of most F-1 hybrids were similar to, or ov er, the high responsive parent and some F(1)s showed intermediate embryo yi elds between their parents. Diallel analysis showed that both additive and dominant effects were significant at the 1% level for the genetic control o f microspore embryogenic ability in both species. Dominant genes had positi ve effects on microspore embryogenesis. In oilseed rape, the additive effec ts were important, while in Chinese cabbage the dominant effects were large ly contributed. The broad- and narrow-sense heritabilities were 0.972 and 0 .811 in oilseed rape, and 0.959 and 0.659 in Chinese cabbage, respectively. From the results of the segregation of embryo yields in the F-2 population of 'Lisandra' x 'Kamikita', it is considered that the microspore embryogen ic ability is controlled by two loci with additive effects in oilseed rape.