Analysis On Genetic Diversity Of Jatropha Curcas Linn In Sichuan-Yunnan Region By AFLP Technology

Jatropha curcas Linn belonging to Jatropha Linn of Euphorbiaceae, is considered to originate in Mexico.The seed can be extracted oil which processing biofuel.It is a kind of important oil-bearing tree species.At present, the studies on this plant focus mainly on Biodiesel production, phytochemisty and toxicology, but those on genetics and molecular biology are relatively rare. The 10 wild populations totally 200 individuals from Sichuan-Yunnan region were investigated by the technique of AFLP analysis and compared on the genetic diversity, genetic differentiation, and genetic structure of wild populations of the 10 species. The contents and the main results of this study were as followings:1.The improved CTAB method was used to extract DNA from the young leaves of Jatropha curcas Linn. Using agarose gel electrophoresis, ultraviolet absorbance spectrophotometer and AFLP analysis tested the DNA samples extracted from above method. The method obtained high quality DNA which has a good structural integrity, with the OD260/OD280 value 1.8-1.95.So this method was the best and perfectly suitable for AFLP analysis.2.All the samples were selected and analyzed by AFLP-silver staining protocol using 5 pairs of AFLP primers screened, total 417 bands which include polymorphic 352 bands were obtained, the percentage of polymorphic band(P)was 84.4%.As for Jatropha curcas Linn populations at the genus level, the effective number of alleles per locus(Ae) was 1.6819,and Nei's gene diversity index(H) was 0.5559, Shannon's information index(I) was 0.6665.3.Genetic differentiation coefficients among ten populations(GST) was 0.0656, respectively, which showed small partial genetic diversity present among ten populations. This result was approved by AMOVA.4.The UPGMA cluster based on Nei's distance matrix was analyzed and some further analysis about the relationships among the populations was made. UPGMA cluster analysis based on genetic identity of 10 populations of Jatropha curcas Linn reflected relationships of materials. Firstly, the populations SCHPZ and SCJH were departed from other eight populations.Secondly, the population YNSB was departed from SCHL, SCHD, YNFY, YNPE, YNSXBN, SCLB, YNLS.At last, population SCLB and population YNXSBN show the closest relationships. There was not a relationship between genetic and geographical distances among populations analyzed by SPSS software.