Studied On Cluster Analysis Of Pepper(Capsicum Annuum L) Inbred Lines By SRAP And Genotype Value

Heterosis breeding is one of the main techniques in hot pepper (Capsicum annuum L) breeding. The genetic relationship between inbred lines of hot pepper is very important in heterosis breeding. According to the breeding goal of the green hot pepper in south China region, the genetic relationship among thirty-one inbred lines and four hybrid were studied by a new molecular marker, SRAP (Sequence-related amplified polymorphism), and a comparison between the analysis based on SRAP markers and that based on the classic genotype values was also carried out. The main results were as follows:The SRAP PCR reaction was established by optimizing the parameters including protocol, concentration of DNA template and Mg2+. The SRAP PCR reaction system was initially denaturing at 94°C for 5 min, The first five cycles are run at 94°C, 1 min, 35°C, 1min, and 72°C,1 min ,for denaturing, annealing and extension, respectively. Then the annealing temperature is raised to 50°C for another 35 cycles. In this system of SRAP PCR, the optimum concentration of DNA template and Mg2+were 15ng/25μl, 2.0mmol/L, respectively. The new established SRAP PCR system of hot pepper was fully reproducible and good stability.Twenty-seven out of thirty primer combinations amplified 310 polymorphic bands in thirty-five hot pepper materials. 3-28 polymorphic bands could be amplified from each primer combination, with an average being 11.5 bands. This suggested SRAP was an effective marker in hot pepper genetics field.310 SRAP markers of thirty-one hot pepper inbred lines were studied by UPGMA (Unweighted pair group method arithmetic average) and five similar coefficient calculation methods. The results showed that Yule coefficient was a preferably method in hot pepper classification based on 310 SRAP markers. In the cluster analysis based on Yule coefficient, C. annuum var. longum and C. annuum var. grossum were divided at GS0.55; At GS0.70, thirty-one pepper inbred lines were classified into five groups: group I including No. 7and No. 9; group II including No. 26 and No. 27; group III including No. 23, 25, 22, 21, 20, 19,18, 17, 14, 6, 11, 24, 10, 15, 13, 8, 16,12, 5 and 4; group IVincluding No. 29...