Polymorphisms of Mitochondrial COII and16S rRNA Gene in Meloidogyne enterolobii on Mulberry

Abstract This study explores the genetic diversity and polymorphisms of Meloidogdyne enterolobii (M enterolobii) on mulberry in China. The sequence of cytochrome oxidase subunit II (COII) and 16S rRNA gene in M enterolobii populations in Guangdong, Guangxi, and Hunan Provinces were PCR-amplified, sequenced, and analyzed for genetic diversity. The haplotypes (Hap) numbers, the total number of mutations, the average number of nucleotide differences (K), haplotype diversity (Hd), and nucleotide diversity (π) of mtCOII gene were 14, 25, 3.563, 0.942 and 0.00429, respectively. The significant differences in Fst value (0.125) and a high level of gene flow (2.83) were detected among the 19 M enterolobii populations. High genetic variation within each population and a small genetic distance among populations was observed. Both phylogenetic analyses and network mapping of the 14 haplotypes revealed a dispersed distribution pattern of the 19 M enterolobii populations. There was an absence of branches strictly corresponding to the 19 range sampling sites. The analysis of molecular variance (AMOVA) revealed that the genetic differentiation of M enterolobii populations was mainly contributed by the variation within each of the defined geographical groups. No significant correlation was found between the genetic distance and geographical distance of 19 M enterolobii populations. This study provides theoretical basis for the future control of M enterolobii and also provides a guarantee for the production of other hosts of M enterolobii.