Study On Regeneration And Genetic Transformation Of Cucumber(Cucumis Sativus L.)

Cucumber (Cucumis sativus1.) is one of the main vegetable crops in China. Modern biotechnology provides a new way for germplasm improvement, which changes the technology from the macroscopic level to microcosmic level. In this study, three special genotypes of cucumber were used to establish the regeneration system. Influence of the genotype, explant type, different plant growth regulater levels on the regeneration rate of cucumber were recorded. Expression vector of CsERFl was also constructed. In addition, effects of appropriate concerntration of agrobacterium, infection time, and co-culture time on genetic transformation were studied. The main results were as follows:1. The regeneration abilities of Zaoer N, D8and JIN5-508have great differences. D8is higher than others. Regeneration frequency and shoots per explants were76%and2.0, Zaoer N is the lowest, the regeneration frequency and shoots per explants were65%and1.1. The best explant of the three genotypes was cotyledon node. The optimal culture mediums of shoot induction were MS+6-BA2.0mg/L+ABA1.0mg/L+AgNO32.0mg/L, MS+6-BA1.5mg/L+ABA0.5mg/L+AgNO32.0mg/L,MS+6-BA1.5mg/L+ABA1.0mg/L+AgNO32.0mg/L, respectively for Zaoer N, D8and JIN5-508. The optimal culture medium of elong was MS+6-BA0.12mg/L.2. Cotyledon of Zaoer N was used as explant for inducing callus. The optimal culture medium of callus induction was MS+IAA0.3mg/L+6-BA1.0mg/L+NAA0.1mg/L. The optimal culture medium of shoot induction was MS+IAA0.4mg/L+6-BA1.0mg/L.3. Expression vector of CsERF1gene was constructed. The tolerance and sensitivity of cucumber cotyledon to Kan was studied. The selection pressure concentration of Kan were75mg/L in Zaoer N and D8;60mg/L in JIN5-508. The tolerance and sensitivity of rooting on this three genotype was60mg/L.500mg/L Cefotaxime can effectively restrain the growth of Agrobacterium. Inoculated with ERA-105agrobacterium tumefacious for20minutes, cocultured for2.5days on culture medium.