Plant viruses are obligate parasites whose survival is contingent upon their ability to move from one plant to another. For a majority of the plant viruses, movement from plant-to-plant is accomplished by means of insect vectors. With the exception of a few well studied model systems, mechanisms underlying the insect transmission of many economically important plant viruses are not well understood. By integrating basic and applied studies, our research seeks to address questions concerning the complex interactions among insect, virus and plant, and how these interactions result in virus transmission and diseases. Insights into these interactions can be a key to the development of strategies for effective virus disease management. We are interested in recalcitrant and emerging insect-transmitted viruses that are important to subtropical agriculture. Currently, one area of focus is emerging viruses from the genus Crinivirus that are vectored by different but specific whitefly species. The interaction of a virus with its specific vector, which results in the transmission of the virus, is influenced by properties of the virus capsid protein and intrinsic features of the insect vector. Therefore, we are exploring the function of capsid proteins encoded by these viruses and are interested in studying interactions between viruses and insects using a combination of biological, molecular, cell biology, and biochemical approaches.

• Salem, N.M., Chen, A.Y.S., Tzanetakis, I.E., Mongkolsiriwattana, C., and Ng, J.C.K. 2009. Further complexity of the genus Crinivirus revealed by the complete genome sequence of Lettuce chlorosis virus (LCV) and the similar temporal accumulation of LCV genomic RNAs 1 and 2. Virology (In press).

• Ng, J.C.K., and Falk, B.W. 2006. Bemisia tabaci transmission of specific Lettuce infectious yellows virus genotypes derived from in vitro synthesized transcript-inoculated protoplasts. Virology 352, 209-215.

• Ng, J.C.K., and Falk, B.W. 2006. Virus-vector interactions mediating nonpersistent and semipersistent plant virus transmission. Annual Review of Phytopathology 44: 183-212..
• Ng, J.C.K., Josefsson, C., Clark, A., Franz, A., and Perry, K.L. 2005. Virion stability and aphid vector transmissibility of Cucumber mosaic virus mutants. Virology 332, 397-405.
• Ng, J.C.K., and Perry, K.L. 2004. Transmission of Plant viruses by aphid vectors. Molecular Plant Pathology 5(5), 505-511.
• Ng, J.C.K., Tian, T., Falk, B.W. 2004. Quantitative parameters determining whitefly (Bemisia tabaci) transmission of Lettuce infectious yellows virus and an engineered defective RNA. Journal of General Virology 85, 2697-2707.
• Baumann, L., Thao, M.L., Funk, C.J., Falk, B.W., Ng, J.C.K., and Baumann, P. 2004. Sequence analysis of DNA fragments from the genome of the primary endosymbiont of the whitefly Bemisia tabaci. Current Microbiology 48, 77-81.
• Thao, M.L., Baumann, L., Hess, J.M., Falk, B.W., Ng, J.C.K., Gullan, P.J., and Baumann, P. 2003. Phylogenetic evidence for two new insect-associated chlamydia of the family Simkaniaceae. Current Microbiology 47, 46-50.
• Ng, J.C.K., Liu, S., and Perry, K.L. 2000. Cucumber mosaic virus mutants with altered physical properties and defective in aphid vector transmission. Virology. 276, 395-403.
• Ng, J. and Perry, K.L. 1999. Stability of the aphid transmission phenotype in Cucumber mosaic virus. Plant Pathology 48, 388-394.