The sweetpotato whitefly, Bemisia tabaci, acts as a vector of more than 100 plant viruses. B. tabaci is known to harbor a primary endosymbiont (Portiera) and 6 secondary endosymbionts (Arsenophonus, Cardinium, Fritschea, Hamiltonella, Rickettsia and Wolbachia). These endosymbionts play important roles in the acquisition and transmission of plant viruses. Using PCR analysis, we identified endosymbiotic bacteria in various B. tabaci populations collected from different places of Korea. Distribution of endosymbionts was different according to the biotype of B. tabaci. Subsequently, their relative densities of endosymbionts were compared between TYLCV-viruliferous and non-viruliferous populations of the Q biotype using quantitative realtime PCR. We found that the densities of Portiera, Cardinium and Hamiltonella are higher in viruliferous than non-viruliferous whiteflies. Our results suggest the role of endosymbiont for the TYLCV transmission of whiteflies.

• S. M. Hemayet Jahan(Department of Agricultural Biology, Kyungpook National University)
• Hong-Soo Choi(National Institutes of Agricultural Science and Technology, RDA)
• Kwan-Suk Lee(National Institutes of Agricultural Science and Technology, RDA)
• Chang-Suk Kim(National Institutes of Agricultural Science and Technology, RDA)
• Sukchan Lee(Department of Genetic Engineering, Sungkyunkwan University)
• Kyoeong-Yeoll Lee(Department of Agricultural Biology, Kyungpook National University)