| There are abundant wild germplasm of cerasus campanulata extensively distributed in the southern district of China.But up to now, there were only few report on accession investigation and evaluation of molecular genetic diversity of Cerasus campanulata. In this research,total 419 accession samples were randomly collected from thirteen populations from Fujian,Guangxi,Taiwan,Jiangxi province to get genomic DNA to understand the genetic diversity by SSR markers .In addition , the relationship between Cerasus campanulata and it's submarginal plants were compared. The main results were as follows,(1)On the species level, the average number of alleles (A) and effective number of alleles (Ne) of Cerasus campanulata was 7.4000 and 3.5903, respectively. Shannon diversity index was 1.4269 on average. The mean expected heterozygosity (He) was 0.6904.The mean Nei's diversity index (h) was 0.6893. All this suggests a relatively high level of genetic diversity in Cerasus campanulata species. The fixation index (F) was -0.02537 on average, which showed excess of heterozygotes.(2)By the population level, the populations from Zhangping and Liancheng in Fujian province were with the highest number of alleles (A=3.5903),while the population from Anle county in Jiangxi province was the lowest(A=.3.3000). The population from Zhangping county in Fujian province was the highest (Ne=3.2131),and the population from Dehua county in Fujian province was the lowest with the effective number of alleles(Ne=2.3066). The Shannon diversity index of Zhangping county in Fujian province was the highest (I=1.2259),while the Shannon diversity index of Dehua county in Fujian province was the lowest(I=0.9004). For the expected heterozygosity (He), the Wutun county population from Wuyi mountain in Fujian province was the highest(He=0.6339),but the Dehua county population in Fujian province was the lowest(He=0.4915). The range of Nei's gene diversity index among populations is from 0.4732 to 0.6258. The fixation index (F) of 12 populations F<0, which showed excess of heterozygotes and significant deviations from Hardy-Weinberg equilibrium in every population.(3)Shannon diversity index ordered from the hightest to the lowest among 13 populations, there were Zhangping county,Liancheng county,Shaowu county,Wutun county,Nanping county,Shaxian county in Fujian province,Qujiang county in Guangdong province,Xingcun county in Fujian province,Ali mountain county,Yangming mountain county in Taiwan province,Anle county,Ganxian county in Jiangxi province,Dehua county in Fujian province,respectively. (4)For the Nei's gene diversity index,the order of the 13 populations were Wutun county,Zhangping county,Shaowu county in Fujian province,Qujiang county in Guangdong province ,Liancheng county,Wuyi mountain Xingcun county,Nanping county,Shaxian county in Fujian province,Anle county in Jiangxi province,Ali mountain county in Taiwan province,Ganxian county in Jiangxi province,Yangming mountain county in Taiwan province,Dehua county in Fujian province.This was a slight difference from the conclusion by Shannon phenotype diversity analysis,but ,they are much similar in trends.(5) The coefficient of genetic differentiation was 0.1477 on average,which indicating that 14.77% of the genetic variation occurred among populations and 85.23% occurs within populations.That means a relatively high level of genetic differentiation among populations despite the existence of most genetic variation within populations. The gene flow (Nm) revealed is 1.4427, which shows a low gene flow among the 13 populations of Ceracus campanulata.(6) The cluster analysis,based on Nei's genetic distance by means of UPGMA and NJ,the thirteen populations were to be divided into four groups, the population from Qujiang county was included in group 1,populations from Liancheng county and Zhangpin county in Fujian province were in group 2, two Taiwan populations and two Dehua county and Shaxian county in Fujian province were included in group 3,and the other populations were in group 4.(7) Significant correlation was found between geographical distance and genetic distance of the 13 Cerasus campanulata populations.(8) Hardy-Weinberg test for 10 SSR locus,there were significant deviation from Hardy-Weinberg equilibrium.(9)For the significantly or extremely deviation from Hardy-Weinberg equilibrium there might be different gene complexes in these populations. Therefore,under the condition of multi-locus there were significant genetic differentiation among wild populations of Cerasus campanulata. The findings of Ohata linkage disequilibrium, D2ST﹥D2IS,D′2IS﹥D′2ST,implying that there might be not the systematic forces but the stochastic forces,such as genetic drift might be the main cause of linkage disequilibrium.(10)For phenotype diversity analysis, the thirteen populations were divided into upon Mahalanbis Distance Method three groups. Populations from Ganjiang and Anle from Jiangxi province were included in group 1,populations from Xingcun county, Wutun county,Shaowu county ,Shaxian county,Dehua county,Nanping county in Fujian province were included in group 2,populations from Liancheng county,Zhangping county in Fujian province,Qujiang county in Guangdong province,Ali mountain county in Taiwan province and Yangming mountain county in Taiwan province were in group 3.(11)The results of correlation analysis,showed that there was no significant correlation existed between Mahalanbis Distance and Nei's genetic distance.(12)The cluster analysis,with the UPGMA based on Nei's genetic distance data Cerasus campanulata and it's 12 submarginal were to be divided into three groups. Ceracus campanulata,Ceracus schneideriana Koehne and Ceracus schneideriana Koehne-like plant were included in group 1. C. yedoensis X P. campanulata,C. yedoensis Maxim.cv.Yedoensis,C. pseudocerasus,C. xintrorsa Yagi cv.Introrsa,C. serrulata var.lannesiana,C. serrulata var.subhirtella were in group 2. P.armaniaca L,P.mume,P.salicina Lindl,P.persica (L.) Batsch were included in group 3.With the information of genetic diversity and the genetic structure of Cerasus campanulata, the author proposed strategies for using genetic diversity both within and between populations.
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