Genetic Analysis And Identification Of Germplasm Resources Of Siraitia Grosvenorii By Rapd Markers

Siraitia grosvenorii (Swingle) C. Jeffrey ex Lu et Z. Y. Zhang is a species of Siraitia in Cucurbitaceae, which is a special local product with important medical and health care value in Guangxi province. We made genetic analysis and identification of fifteen germplasm materials of S. grosvenorii (including ten cultivated varieties and five wild materials) by RAPD markers. The rusults showed as follows:1. The genome DNA of S. grosvenorii with high concentration and purity could be obtained with the improved method of SDS, which is good enough for RAPD amplification.2. An optimized reaction system of RAPD was summed up based on the experimental results in the present study. This system has 25 μl reaction volume, including super pure water 17.8 μl,10XEx Taq Buffer 2.5μl (containing 20mmol/L Mg2+) , 2mmol/L dNTP 2.5 μl, 10 μmol/L random primer 1 μ l, Ex Taq DNA Polymerase 0.2 μl (1U) , template DNA 1 ul (50ng/reaction) . The optimal PCR amplification procedure indues: Pre-denaturation at 94℃ for 4 min; and 35 cycles of denaturation at 94℃ for 30 sec, annealing at 37℃ for 30 sec, lengthening at 72℃ for 1 min; and then again lengthening at 72℃ for 7 min. The find products were kept at 4℃.3. The results of RAPD cluster showed that the genetic relationship among the cultivated varieties of the round-fruits was close, but that between the round-fruited and the long-fruited cultivated varieties was far away from each other, and the long-fruited cultivated varieties showed even closer genetic relationship to the wild genotypes. Among the round-fruits, Qingpiguo,Ganziguo and Malingguo showed close genetic relationship and were clustered in a group, while Baimaoguo, Hongmaoguo, Bolin No.2 and Chashanguo were clustered in another group. Among the long-fruits, Lajiangguo and Dongguaguo showed close genetic distance, but they were far away from Changtanguo in genetic distance.