Genetic Diversity and Population Structure of the Peanut Worm (Sipunculus nudus) in Southern China as lnferred from Mitochondrial 16S rRNA Sequences

摘要

Genetic diversity and population structure of the peanut worm (Sipunculus nudus) were investigated by using 536 base-pair fragments of the mitochondrial 16S ribosomal gene. Populations were collected from three locations along the southern coast of China - Beihai, Sanya, and Xiamen. Amplified polymerase chain reaction products were sequenced in both directions and data were analyzed using ClustalX, Arlequin, and MEGA. A total of 69 polymorphic sites and 21 distinct haplotypes were revealed, The mean haplotype and nucleotide diversity of the three populations were 0.814% and 0.37%, respectively. The Beihai population had the greatest haplotype and nucleotide diversity, followed by the Xiamen and Sanya populations. Analysis of molecular variance (AMOVA) showed significant genetic differentiation among the three populations (Fst = 0.0619, p<0.05) and distinct population structures among the three sites.