Allozymic Variation And Genetic Diversity Analysis On Different Population Of Primus Mongolica

Prunus mongolica Maxim. which belongs to Prunus in Rosaceace is aperennial, xerophilous and national third level protective plant. Prunusmongolica Maxim has a drought resisting, drought tolerance, barrenresistance peculiarity as well as was a water and soil conservation, landscapeplants for the desert region. So understanding the genetic diversity of Prunusmongolica Maxim. has a significant meaning to breed and protect thegermplasm resources in the future.In this paper, genetic diversity of4natrual populations of Prunusmongolica Maxim. were investigated by using allozyme analysis. To analyzethe10kinds of allele enzyme system (peroxidase, catalase, cytochromeoxidase, superoxide dismutase, α-amylase, ester enzyme, phosphorylationenzyme, ascorbic acid oxidase, acid phosphatase, malatedehydrogenase)express20gene loci and35alleles. On the basis of theclustering analysis of experimental data by Spss software, we can reach thefollowing conclusionS:1.The mean number of alleles per locus(A)was1.8333, the effectivemean number of alleles per locus(Ae)was1.9172.The percentage ofpolymorphic loci(P) was76.67%.The average expected heterozygosity(He）and observed heterozygosity (H0) were0.3716and0.6421respectively. Theactual heterozygosity was1.7times expected heterozygosity.Therefore thephenomenon of inbeeding was unconspicuous serious in Prunus mongolica populations. The fixation index(F)was0.3917>0,which indicated that thewhole Prunus mongolica Maxim.populations was heterozygote insufficiencyand homozygote excess.2.The mean value of DSTover all loci was0.0336, the value of GSTwas0.0690, approaching to0.1. Which proved that most of the genetic variability（92.10%）existed in individual populations and a small proportion(6.90%)among populations. The division level of GSTdenoted that the geneticdifferentiation of Prunus mongolica was relatively low.But exsist the certaingene flow. The value of Nm was4.022.3.The4populations were classificational analyzed by UPGMA(unweighted pair-group method with arithmetic average), according to thegenetic identity and genetic distance，the results showed that the geneticdistances were so approximate in the populations from the same location, andthey clustered together. Basically, the nearer spatial distance was，the closergenetic distance they had. This was identical with spatial distribution pattern.4.There was not prominent correlation between the genetic diversityindices of Prnus mongolica (Allele effective number and the averageexpected heterozygosity) and attitude and precipitation.5.According to the above analysis of genetic diversity index of Prunusmongolica, we could figure out, Prunus mongolica is a high genetic diversityplant, the main reason for leading to Prunus mongolica endangered was notthe barren of genetic diversity, but the growing environmental was damaged. Therefore, the establishment of nature reserves, to reduced the interference ofthe growth environment was the main countermeasures to protect Prunusmongolica.