栀子遗传多样性及遗传分化的RAPD分析

 目的应用随机扩增多态性DNA(random amplifed polymorphic DNA,RAPD)标记技术对栀子8个种群遗传多样性和遗传分化进行研究。方法18种随机引物对92个个体进行检测,应用POPGENE软件和AMOVA软件对结果进行处理。结果共得到120个可重复的位点,其中多态位点75个,多态百分率为62.5%。各种群内多态位点百分率在39.17%～68.83%之间,平均为56.98%。河南南阳(POP1)种群最高,其次是江西新干县野生种群(POP7),最低是江西抚州水栀子种群(POP3)。Shannon指数和Nei指数均反映出栀子各种群具有较高的遗传多样性。Shannon指数为0.431 3,各种群Shannon指数在0.2256～0.380 6之间,Nei指数为0.289 2,各种群Nei指数在0.148 2～0.263 0之间。AMOVA揭示种群内遗传多样性占总遗传多样性的76.05%,而种群间遗传多样性只占23.95%。运用POPGENE也得出种群内遗传变异(69.34%)大于种群间(30.66%)的结论。种群间的遗传分化系数为0.306 6。栀子种群间的基因流为1.130 6,遗传相似度平均为0.129 09,遗传距离平均为0.880 72。根据遗传距离聚类分析,河南南阳种群(POP1)与江西樟树新干种群(POP4,POP5,POP6,POP7)聚为一类,湖南种群(POP8)与江西抚州栀子种群(POP2)聚为一类,江西抚州水栀子种群(POP3)与其他各种群间的遗传关系较远。结论目前,虽然野生资源逐年减少以及多年栽培中的品种选育,栀子遗传多样性仍较丰富,且种群内大于种群间,种群间存在较少的遗传分化。

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.