RAPD Analyses Of Genetic Diversity Of Capsicum Annuum L.

The seeds of Capsicum annuum including CM. var. fascioculatunt Irish, C.a.var. longum Sendt, C.a.var.grossum Sendt, C.a. var.conides Irish and some first filial generations of C.a. var. longum Sendt were collected as tested materials from Jiangxi, Hunan, Guangxi Provinces in China and from the Republic of Korea. A stable and duplicable technological system of RAPD analysis was developed to evaluate the genetic diversity of the collected pepper germplasm resources to provide scientific basis for the utilization of heterosis of Capsicum annuum and to provide molecular evidence for the sub-classification within Capsicum annuum. The results were showed as follows:l.The parameters involved in RAPD analysis were optimized for pepper: the total volume of 25ul containing 160umol/LdNTP, 0.2umol/L random primers, 30~50ng template DNA,1.5 unit Taq enzyme. The program for the PCR amplification was that first denatured the template DNA at 94 "Cfor 4min and then denatured the DNA at 94 癈 for Imin; annealed at 37 癈 for l.Smin, extended at 72"C for l.Smin, 40 cycles, then extended at 72 癈 for 7min and kept the reaction at 4 癈 until it was taken out. Under this RAPD system, the amplification bands in the gel were clear, stable and duplicable.2.The total of 1258 DNA bands were amplified in the 22 pepper germplasm resources by the above PCR procedure using 14 random primers, and about 50% of the bands were polymorphic, indicating that the genetic background was narrow in Capsicum annuum L. involved in this experiment.3.An cluster analysis was made by using the RAPD data of the varieties and some first filial generations of Capsicum annuum involved in the experiment, the result showed that the germplasm resources were divided into 3 subclasses when the value of D was 0.69. The first subclass was C.a .var. grossum Sendt, the second was CM. var. conides Irish, and the third included CM. var. fascioculatunt Irish and CM. var. longum Sendt. The third subclass was further divided into C.a. var fascioculatunt Irish and C.a. var. longum Sendt when the value of D was 0.75, indicating that among the subclasses of Capsicum annuum L, C.a. var. fascioculatunt Irish related to C.a. var. longum Sendt genetically and then to CM. var. conides Irish, and CM. var. grossum Sendt shared larger difference with CM. var. fascioculatunt Irish and CM. var. longum Sendt.