Genetic analysis for six wild and selection populations of common carp (Cyprinus carpio) using microsatellites

We genotyped a total of 208 individuals of common carp (Cyprinus carpio) from four wild populations Qingshuijiang (QSJ), Taihu (TH), C.carpio haematopterus (Huangheli, HHL) and C.carpio amurensis (Heilongjiang, HLJ) and two selected strains C.carpio var. FFRC (FRL) and C.carpio var. specularis 'Song-pu' (SPJ) by using 12 microsatellite markers. Altogether 341 alleles were detected in 12 loci, with an average of 28.67 alleles per locus, and one locus (HLJ1127) was under strong selection pressure. Two selection strains showed lower genetic diversity parameters values than four wild populations. Strain SPJ showed the lowest genetic diversity parameters values (N_a=6.82, H_o=0.54 and PIC=0.50), whereas Strain QSJ presented the highest parameters values (N_a=21.25, H_o=0.80 and PIC=0.91). The analysis of molecular variance indicates that most of the genetic variance was within populations; however, significant genetic divergence among populations was detected (P<0.01). Similar results had been found by UPGMA dendrogram and PCoA plots using Nei's genetic distances among six populations. The wild populations had closer genetic distance and clustered together earlier, but were clearly separated from two selection strains. The PCoA plots and genetic structure analysis reveal the distinct genetic structure of individuals from selection individuals and partial complexity genetic structure of wild individuals. In brief, wild C.carpio populations in China have high genetic diversity and good genetic purity in their selection strains.