RAPD Analysis Of Germplasm Resources In Cauliflower

The random amplified polymorphic DNA marker (RAPD) was applied to detect the genetic relationships and diversity among 37 germplasm materials of cauliflower cultivars. The main results were summarized as follow:1. Five essential factors that might affect the result of RAPD are optimized by applying orthogonal experiment. The results showed that the optimal conditions of five factors in RAPD-PCR reaction system are dNTPs 0.12mmol·L-1, random primer 0.8-1.6μmol·L-1, DNA template 20-80ng, Taq polymerase 0.75 U, annealing temperature 34-36℃.2. A total of 80 RAPD primers were screened for the amplification on cauliflower cultivars 16,17,20, 23,25,31 and 33. Among which 48 primers gave polymorphism,25 primers gave monomorphic and 7 primers without amplified bands within the varieties. Among the 48 polymorphic primers, primers S11, S15, S16, S17, S18 and S65 could obtain stable, clear and polymorphic bands, the percentage of polymorphic bands ranging from 16.7% to 75%, and these primers appear to be useful for genetic diversity studies in cauliflower cultivars.3. The results of RAPD cluster analysis with primer S17 showed that 37 germplasm materials of cauliflower cultivars were separated into 4 groups at the genetic distance was 0.41. The cluster results showed that the genetic diversity of the cauliflower cultivars inconsistent with their geographical origins and growth period.