Study on Seed Morphology and Genetic Diversity of Jatropha curcas L. from Different Provenances

摘要

Jatropha curcas L., a multipurpose shrub has acquired significant economic importance for its seed oil which can be converted to biodiesel, is emerging as an alternative to petro-diesel. The present study aims at characterization of the seed morphology and genetic diversity of Jatropha curcas L. from eight different provenances for providing support for the breeding and allocation of seed. Five traits were investigated, including hundred seed weight, seed length, width, lateral diameter, seed length and width ratio. The genetic diversity of eight populations from different provenances was estimated using DALP method (5 primers). The results showed that seed morphology had significant variation among locations. Five DALP primers generated highly reproducible and stable DNA fragments. 219 of 244 loci were polymorphic, i.e., PPB was 89.75%. And POPGENE analysis indicated the total Nei's gene diversity (H) was 0.2878, the total Shannon's Information index (Ⅰ) was 0.4331, and the coefficient of Gene differentiation (Gst) was 0.8200 among populations, namely 82.00% genetic variation occurring among populations and 20.00% remaining within population. It was suggested that a high level of genetic variation should be occur among the different populations of J. curcas. The high genetic differentiation among the populations could be caused by not only the limited gene flow (Nm = 0.1097) but also the genetic drift. The result indicates that the seed morphology among populations showed some certain differentiation. The eight populations had high level of genetic diversity and show apparent genetic differentiation. So that provenance selection has great potentiality.