Bemisia tabaci (Gennadius) biotypes B and Q are two invasive biotypes in the species complex. The comparison of the population genetic structure of the two biotypes is of significance to show their invasive mechanism and to their control. The intersimple sequence repeats (ISSR) marker was used to analyze the 16 B-biotype populations and 4 Q-biotype populations worldwide with a Trialeurodes vaporariorum population in Shanxi Province,China,and a B. tabaci non-B/Q-biotype population in Zhejiang Province,China,was used as control populations. The analysis of genetic diversity showed that the diversity indexes of biotype Q including Nei's gene diversity index,Shannon informative index,and the percentage of polymorphic loci were higher than those of biotype B. The high genetic diversity of biotype Q might provide the genetic basis for the excellent ecological adaptation. Cluster analysis suggested that the ISSR could not be used in the phylogenetic analysis though it could easily distinguish the biotypes of B. tabaci. The difference of the population genetic structure between the biotype B and the biotype Q exists based on the ISSR marker. Meanwhile,the results suggested that the molecular marker has its limitation in the phylogenetic analysis among the biotypes of B. tabaci.
烟粉虱B em isia tabaci(G ennad ius)是一种取食植物汁液的重要农业害虫,同时也是许多植物病毒最重要的传播介体之一。烟粉虱被认为是由许多具有明显遗传分化的不同种群即生物型组成的复合种,其中B型烟粉虱是一种入侵性最强的生物型,几乎在世界各地均有分布。由于不同生物型的烟粉虱在寄主范围、传毒能力、地理分布、抗药性等许多生物学方面存在差异,因此对烟粉虱生物型的鉴定及其遗传分化研究对于该害虫的可持续控制具有重要的指导意义。烟粉虱生物型的鉴定方法包括生物学鉴定、酶谱鉴定以及分子标记鉴定的方法,其中使用的分子标记包括RAPD、AFLP、rDNA-ITS1、m tDNA CO I以及SSR等标记。目前,不同生物型的烟粉虱尤其B型烟粉虱的分类地位仍然存在争议。介绍了不同生物型烟粉虱的生物学差异、鉴定方法及其遗传分化研究的最新进展,同时探讨了不同生物型烟粉虱的分类地位和研究方向。
