Identification of begomoviruses associated with the insect vector Bemisia tabaci and various host plants on Java...

Begomoviruses are economically important plant viruses and are transmitted by Bemisia tabaci which is a complex of various cryptic species. However, it is uncertain whether most begomoviruses that infect host plants are transmitted by B. tabaci at a similar rate. We compared the begomovirus profiles that were detected in a total of 37 whitefly populations and 52 host plants on Java Island, Indonesia. Seven begomovirus species were detected in B. tabaci at different rates: pepper yellow leaf curl Indonesia virus (PepYLCIV, 56.8%), tomato yellow leaf curl Kanchanaburi virus (TYLCKaV, 46.0%), tomato leaf curl New Delhi virus (ToLCNDV, 21.6%), squash leaf curl China virus (SLCCNV, 21.6%), ageratum yellow vein China virus (AYVCNV, 2.7%), mungbean yellow mosaic India virus (MYMIV, 2.7%), and okra enation leaf curl virus (OELCuV, 2.7%). The begomoviruses were detected at different rates in three cryptic species of B. tabaci. In addition, six begomovirus species were detected in the various host plants at different rates: PepYLCIV (67.3%), TYLCKaV (53.9%), ToLCNDV (13.5%), MYMIV (11.5%), AYVCNV (3.9%), and Tomato yellow leaf curl Thailand virus (TYLCTHV) (1.9%). By comparing the virus presence between whiteflies and plants, five begomoviruses (AYVCNV, MYMIV, PepYLCIV, ToLCNDV, and TYLCKaV) were detected in both samples, but their sequence similarity was highly variable depending on the begomovirus themselves; TYLCKaV was highest (99.4%-100%) than any other viruses. Our study suggests B. tabaci acquire begomoviruses at different rates from plants. This study provides important information on the potential variation in the begomovirus transmission mechanism.