Study on Genetic Diversity and Differentiation of Gardenia jasminoides Ellis Using RAPD Markers

OBJECTIVE To investigate the genetic diversity of 8 populations of Gardenia jasminoides Ellis using RAPD.METHODS 18 Primers were selected from 60 primers.RESULTS The levels of genetic variation and patterns of population structure in Gardenia jasminoides Ellis were investigated using RAPD markers.Of the 60 primers screed,18 primers produced highly reproducible RAPD bands,using these primers,120 discernible DNA fragments were generated with 75(62.5%) polymorphic fragments,indicating considerable genetic variation at the species level.In contrast,there were relatively high levels of polymorphism at the population level with the percentage of polymorphic bands ranging from 39.17%~68.83%.With mean percentage of polymorphic loci(P=56.98%).Low levels of genetic differentiation among populations were detected based on Nei's genetic diversity analysis(0.289 2),shannon's diversity index(0.431 3),and AMOVA(0.239 5).An indirect estimation of historical levels of gene flow(Nm=1.130 6) was consistent with the high mean genetic identity(mean= 0.880 72) found between populations.There was correlation between genetic and geographic distance.The clustering analysis was performed using the software POPGENE32.8 Populations were divided into 3 clusters,namely cluster 1(POP4,POP5,POP6,POP7 and POP1),cluster2(POP2 and POP8) and cluster3(POP3).The genetic distance of POP3 with other populations was large.CONCLUSION Though the wild resource is decreasing and long-term breed selection yearly,the genetic diversity is high.The genetic diversity within population is higher than that of among population,and there is a little genetic differentiation.