基于线粒体COI基因全长的无锡地区橘小实蝇种群来源分析

Population source analysis of Bactrocera dorsalis(Hendel) based on complete mitochondria COI sequences in Wuxi

本研究以1 535 bp的COI基因全长作为分子标记,通过测序得到橘小实蝇[Bactrocera dorsalis(Hendel)]的海南、广东、广西、湖南、湖北、云南、四川、江西、福建、浙江、上海及江苏的12个种群共240头橘小实蝇个体的COI基因,对其进行种群遗传结构研究,分析江苏无锡地区橘小实蝇的入侵来源。结果表明,研究所涉及的橘小实蝇种群间呈现较显著的遗传结构,但并未出现距离隔离现象,且随着采样点经度和纬度的增加单倍型多样性呈减弱趋势。12个橘小实蝇地理种群分为3个组群进行AMOVA分析显示,组群间变异占总体变异的1.46%,组群内种群间变异占总体变异的4.07%,组群内个体间变异占总体变异的94.47%。表明本研究所涉及范围内的橘小实蝇有由南向北扩散的趋势,无锡地区的橘小实蝇种群很可能来源于广东、江西及浙江地区。

Aim at revealing invasion origin of Bactrocera dorsalis （Hendel） in Wuxi of Jiangsu province, we tested com- plete mitochondrial DNA COI sequences （1 535 bp） and studied population genetic structure of 240 individuals of B. dor- salis collected from 12 sites, including Hainan, Guangdong, Guangxi, Hunan, Hubei, Yunnan, Sichuan, Jiangxi, Fujiang, Zhejiang, Shanghai and Jiangsu. The results showed that overall genetic structure of B. dorsalis in main distribution areas was significant and no sign of isolation-by-distance. Haplotype diversity decreased with increasing of longitude and lati- tude of collection sites, which indicated that B. dorsalis had expanded from south to north in China, and invasion origin of B. dorsalis of Wuxi population was most probably from Guangdong, Jiangxi and Zhejiang.