Research Projects

Mosquito vectors and other insect pests were collected from their natural habitats across south India. Of these 8 mosquito species and 11 insect species were maintained in the insectaria and thereby enriched Wolbachia strain pool was established. Aedes albopictus were treated with tetracycline to establish Wolbachia free colonies for bio-assay crossing experiments. The micro-manipulation technique of the mosquitoes was standardized for effective trans-infection of Wolbachia into mosquito vectors. In parallel to this, Wolbachia was isolated and their viability in in-vitro conditions was evaluated. Aedes albopictus (C6/36) cell cultures were inoculated with Wolbachia isolated from Exorista sorbillans and maintained for 15 passages. The novel infection was established in these cell lines for the first time. The live mosquitoes were trans-infected with Wolbachia and stable infections were maintained till G12 generations. The crossing experiments with Ae. aegypti mosquitoes infected with Wolbachia showed cytoplasmic incompatibility phenotype, which suggests that population replacement strategies can be accomplished through the use of this technology. Specific TaqMan probes have been developed from the sequences of the Ae. albopictus from the current study, which is greatly unique and advantageous. The Wolbachia strain of Ae. albopictus has been sequenced and deposited in the GenBank, NCBI. Novel Wolbachia B supergroup has been identified in the Ae. albopictus of Kerala. The bacterial densities in two Ae. albopictus populations have been characterized for the first time in India. The average CI% was found to be 35% in crosses between populations from different states. The CI% from populations within states was ~14%.