Overview of Distribution and Diversity of Wolbachia Endosymbiont among the Different Geographical Populations of Indian Uzifly, Exorista Sorbillans (Diptera: Tachinidae).

Microorganisms are unique life forms having great impact on functioning and perpetuation of biosphere. Among them, Wolbachia is ubiquitous gram negative rickettsial endosymbiont taking its shelter in somatic and reproductive tissues of class insecta. Wolbachia induces variety of phenotypes within insects from reproductive parasitism to mutualism. Due to the infection dynamics of Wolbachia and its ability to induce reproductive anomalies in their hosts, it has been touted as the most effective bio-control agent for management of insect pests and vectors. However, for implementation of any Wolbachia based bio-control strategies it is essential to know its distribution, diversity and interactions with their hosts. Wolbachia interactions in Uzi fly Exorista sorbillans are well documented and are proposed as agents for management of this pest. However, their distribution and diversity across the entire Indian sub-continent is left void. In the current study 31 populations of Uzi fly collected from the Mulberry Silkworm belts of India have been screened and characterized. 213 samples were screened and infection dynamics in the individuals have been documented. The findings suggest high prevalence of AB Wolbachia super infections in field populations of Uzi fly. This important update on the infection status and diversity of Wolbachia is of greater significance for implementation of the previously proposed Wolbachia based biocontrol strategies of Uzi fly in India

Sex ratio distortion in the Nesolynx thymus (Hymenoptera: Eulophidae), an ecto-pupal parasitoid of uzifly, Exorista sorbillans (Diptera: Tachinidae)

The reproductive alterations induced by maternally inherited alpha-proteo-bacteria Wolbachia to their hosts is a well-documented phenomenon. In Nesolynx thymus, a gregarious hymenopterous ecto-pupal parasitoid of the uzifly, Exorista sorbillans, diagnostic PCR assay using specific primers revealed the presence of Wolbachia. Following genetic crossing experiments, we observed a female biased sex ratio of 1 : 9.5 at 25 degrees C and 1 : 3 male to female ratio when the populations were exposed to heat shock 33 degrees C for six hours. Furthermore, we found infection polymorphism, where female parasitoids are infected by Wolbachia but males are not infected. Infected eggs develop into females, whereas uninfected eggs develop parthenogenetically into males. The results are discussed in the context of the possible mechanism of sex-ratio bias caused by Wolbachia

A preliminary survey for Wolbachia and bacteriophage WO infections in Indian mosquitoes (Diptera: Culicidae)

Maternally inherited Wolbachia endosymbiotic bacteria are known to induce various kinds of reproductive alterations in their arthropod hosts. It has been proposed that this bacterium can be used as a tool for gene drive system in mosquitoes and also for the reduction of population size and modulating population age structure in order to reduce disease transmission. In the present study, we carried out a survey to determine the prevalence of Wolbachia and its phage WO infection in Indian mosquitoes and classified Wolbachia infection into groups A and B based on extensive polymerase chain reaction assay using Wolbachia specific wsp and orf7 gene primers. Out of 20 fieldcaught mosquito species, eight species have shown to be infected. Singly infected with Wolbachia A was found in two species and B group found in four species, while double infection with AB group were found in two species. All the screened mosquito species with positive Wolbachia infection were also infected with phage WO. The knowledge of variation in Wolbachia and phage WO infection rates and inferred susceptibility to infection among different mosquito genera has fundamental implications for designing and successful application of Wolbachia based vector-borne disease control strategies