福建省烟粉虱不同地理种群遗传结构特征

为明确福建省烟粉虱种群遗传结构特征,基于福建省烟粉虱不同地理种群中40个代表性的线粒体COI基因序列,分析了种群遗传多样性、遗传分化及分子变异情况,并构建了单倍型系统发育树与网络图。结果显示:在590 bp长度的mt COI基因序列中有效位点558个,其中187个核苷酸位点存在变异;序列核苷酸中A、T、C、G含量分别为42.32%、24.36%、20.25%、13.06%,其中A+T的含量为66.68%,表现出明显的A+T偏向性;共检测出11个单倍型,其中Hap3、4、7、9、11为特殊单倍型;种群多样性指数为0.838,核苷酸多样性指数为0.093,表明遗传多样性水平较高;AMOVA分析表明种群遗传变异主要来自种群内,总种群遗传分化系数仅为0.027,种群遗传分化较低。表明福建烟粉虱种群基因交流未受地理距离明显影响,种群遗传分化不显著。

Genetic structure of the geographical populations of tobacco whitefly Bemisia tabaci (Gennadius) in Fujian, China

In order to clarify the genetic structure of different geographic populations of tobacco whitefly Bemisia tabaci in Fujian, the genetic diversity, genetic differentiation and molecular variance were analyzed and phylogenetic trees and haplotype network were constructed based on 40 representative sequences of mtDNA COI gene from seven geographic populations of B. tabaci in Fujian Province. The 590-bp mtCOI sequences contained 558 effective sites, 187 of which were variable sites. The percentages of A, T, C, G were 42.32%, 24.36%, 20.25% and 13.06%, respectively, and A+T content was 66.68%, showing a obvious A+T bia. Eleven haplotypes could be defined among the 40 samples, and Hap3, 4, 7, 9, 11 were unique haplotypes. The haplotype diversity and nucleotide diversity of Fujian B. tabaci populations were 0.838 and 0.093, indicating that the level of genetic diversity was high. The percentage of variation within populations was greater than that between populations and the level of genetic differentiation was low. The results indicated that the gene flow was not affected by the geographical distance and genetic differentiation was not significant in Fujian B. tabaci populations.