Identification of the saprophytic endosymbionts in the whitefly (Bemisia tabaci) colonizing cotton and eggplant

Whitefly transmitted virus diseases are a major challenge in improving productivity of agricultural and horticultural crops. The survival or increased fitness of the vector Bemisia tabaci is attributed to bacterial endosymbiont present in their body parts. In recent year, the bacteria are also shown to play a vital role in facilitating transmission of viruses. In the present study, an attempt was made to characterize the obligate and saprophytic endosymbionts in two populations of whitefly, one occurring on cotton plants in the field and the other of vector reared on egg plant in the laboratory. The bacteria were identified by characterization of 16S r RNA genes. Results showed that the whitefly population from cotton field contains Bacillus thuringiensis, Bacillus altitudinis, Bacillus pumillus, Bacillus megaterium, Bacillus subtilis, Bacillus cereus and Bacillus spp., Staphyloccus haemolyticus and Ralstonia spp. in all developmental stages, egg, four instars and in adults. However, in the case of glasshouse reared population, the predominant bacteria were Ralstonia pickettii besides Bacillus pumilus present in instars only.