The Optimization Study of Isolated Microspore Culture System in Cabbage(Brassica oleraca L. var. capitata L.)

In order to efficiently promote embryoid induction of cabbage in microspore culture,Some factors affecting microspore culture of cabbage were studied on 20 genotypes of common cabbage(including different types of F1 and their partly parents),condition temperature,flowering priod,temperature of heat shock treatment time,and the optimal pH in NLN-13.The results show that the microspore embryo yield had no correlation with head types of cabbage,but there was significant relation between different maturity of cabbage and microspore embryo yield,early-maturing materials got higher microspore embryo yield than late-maturing.The microspore embryo yield of F1 lied between their parents whose embryogenic abilities were significant different.Condition temperature had no correlation with microspore embryogenesis efficiency.Regarding quantity and quality of microspore embryo,10 days after the first flower appeared in stem was the optimal period for microspore culture.For most genotypes,32.5℃ heat shock treatment for 48 h had better effect than 24 h.The combined treatment(the combination of heat shock at 32.5℃ for 48 h with pH6.2 in NLN-13) resulted in higher diploids frequency in the regenerated population compared to traditional microspore culture protocol in which usually microspore are cultured in NLN-13(pH5.8) after heat shocking at 32.5℃ for 24 h.