Molecular study of ash psyllids, Psyllopsis (Hemiptera: Liviidae), and their Wolbachia endosymbiont

Three ash psyllid species, Psyllopsis repens Loginova 1963, Psyllopsis securicola Loginova 1963 and Psyllopsis machinosus Loginova 1963, which have been distributed in the Central Asia and Europe, are important pests on genus Fraxinus spp. in the urban area of Iran. They have similar adult and larval morphology as well as same host and biology. On the other hand morphologically identification of adults and nymph, especially for females and damaged adults by removal from sticky traps is difficult. Therefore, a fast and accurate identification method is required. Here we analyzed barcode sequence variation based on two mitochondrial gene regions, cytochrome c oxidase subunit I (mtCOI) and cytochrome b (cytb) as DNA barcode, and one endosymbiont gene (wsp Wolbachia gene) among the species in southern Iran. The results of pairwise genetic distance values showed that cytb and mtCOI genes had the highest inter-specific variability. Based on the results, two species P. machinosus and P. repens which are present on one host plant together probably have been infected with similar Wolbachia strain.