Abstract:

In order to understand the genetic characteristics of Whitmania pigra population, the genetic diversity and population genetic structure of W. pigra populations (AH: Jiangxi Fuzhou population, TH: Anhui Taihe population, JX: Jiangxi Nanchang population, WSH: Shandong Weishan population, JN: Shandong Jinan population) from five locations were analyzed by single nucleotide polymorphism (SNP) markers. The results of the population structure analysis and principal component analysis showed that the five populations could be traced back to three different population sources. The results of phylogenetic tree analysis showed that AH population and TH population had partial branch crossover, and JX population, WSH population and JN population were divided into separate branches. The pairwise F_ST values of the five populations ranged from 0.03 to 0.20, the genetic distance between the two groups ranged from 0.03 to 0.22, the single nucleotide polymorphism (π) ranged from 0.003974 to 0.004131, and the degree of genetic differentiation between populations was low. The content of polymorphism information content ranged from 0.16 to 0.20, the content of observed heterozygosity ranged from 0.18 to 0.27, and the content of inbreeding coefficient ranged from -0.07912 to 0.09063. The mean value of Tajima's D value is positive, that is, the group is in a stable state. The genetic variation among populations mainly comes from within the population, and there is low genetic diversity among populations. It is speculated that it may be that W. pigra has carried out frequent seedling transfer or parental introduction during the breeding process.

Key words: Whitmania pigra, single nucleotide polymorphism, genetic differentiation, genetic diversity, population structure, population genetics, genetic breeding, phylogenetic tree