Allozyme Analysis Of Genetic Diversity In Genus Amygdalus L.

In the present research, 99 accessions of peach and its related species were investigated using vertical slab polyacrylamide gel electrophoresis, to detect allozyme genetic diversity and interspecies relationships, with the hope of assisting the management of peach germplasm resources and elucidating the inter-species phylogenetic relationships.The accessions tested consisted of 5 speach species including Amygdalus persica L.,Amygdalus kansuensis Skeels,Amygdalus davidiana (Carr.) Yu,Amygdalus ferganesis Kov. et Kost. and Amygdalus mira Koehne, 1 plum species.Results of allozyme analysis showed:1. 69 alleles were detected at 24 loci of 11 enzyme systems in 6 species, with the largest number of 8 in one locus. As for genetic diversity of 6 species, mean number of alleles per locus (A), the portion of polymorphic loci (P), mean observed heterozygosity and mean expected heterozygosity were 1.76, 46.53%, 0.282 and 0.305 respectively; Comparison of genetic variation of the 6 species demonstrated that the Amygdalus persica L. had the highest genetic diversity, with P and A being 79.2% and 3; Amygdalus davidiana (Carr.) Yu took the second place, with P and A being 79.2% and 2.3; P and A of Amygdalus ferganesis Kov.et Kost were 45.8% and 1.5; P and A of Amygdalus mira Koehne were 33.3% and 1.3; Amygdalus kansuensis Skeels had lower genetic diversity, with P and A being 16.7% and 1.2.2. Chi-square test to Ho and He of Amygdalus persica L. showed that 15 in 20 polymorphic loci were significant at the level of P≤0.01; 1 polymorphic loci were significant at the level of P≤0.05, implying that they had more heterozygous genotypes than expected value of Hardy-Weinberg.3. Amygdalus ferganesis Kov.et Kost was clustered in Amygdalus persica L., and clustered to Amygdalus persica L.var. necipersica L., the genetic identity of them is 0.973.4. Cluster analysis, with Biosys-2 and TFPGA interspecific relationship analysis and NTSYS2.10 individual analysis, showed that in the dendrogram Amygdalus persica L. was first clustered to Amygdalus ferganesis Kov. et Kost., then to Amygdalus davidiana (Carr.) Yu when all species of speach clustered together firstly, and then to cluster with its related species Prunus salicina Lindl. The 99 accessions could be distinguished by 11 enzyme systems, and the results of 3 softwares were consistent.