Direct somatic embryogenesis in ground-cover chrysanthemum

In this paper,acceptor system of direct somatic embryogenesis in ground-cover chrysanthemum cv.Yurenmian was established.The authors studied the effects of media,hormones on direct somatic embryogenesis through leaf segments as explants,and experiments of the sensitivity of antibiotics were also processed.Results showed that: 1) KT was more efficient than 2,4-D in induction somatic embryogenesis at the same concentration;2) somatic embryogenesis induction medium: MS+KT 2.0 mg/L+2,4-D 2.0 mg/L+NAA 0.5 mg/L.After induction 10 days,explants were transferred into somatic embryogenesis development medium,which was MS plus KT 2.0 mg/L and NAA 0.5 mg/L for 30 days.The highest rate of somatic embryogenesis reached 93.0%,average number of somatic embryogenesis per leaf segment explant was 13.6;3) MS basic medium was more efficient than N_6 and B_5 media for direct somatic embryogenesis;4) experiments of the sensitivity of antibiotics for gene transformation of direct somatic embryogenesis in ground-cover chrysanthemum cv.Yurenmian showed: the selection concentration of kanamycin was 10 mg/L,the selection concentration of cefotaxime was 300 mg/L in former period(during 3-4 weeks) and 100 mg/L later(after four weeks).