Geminivirus transmission by different biotypes of the whitefly Bemisia tabaci (Gennadius)

Begomovirus transmission efficiency assays were performed by the use of different whitefly biotypes from different geographically isolated regions of the world. Viruses from all the five original host plants could be transmitted by the whitefly Bemisi tabaci. Biologically viruses were found to be different from one another based on incubation period, symptom expression and host range studies. A significant difference in transmission assays was noticed under certain conditions i.e., temperature, geographic impact, B and non-B biotypes. B. tabaci non-B biotype populations from Pakistan and Spain were found to be more efficient to transmit begomoviruses from Pakistan as compared to B-biotype. Host range resulted almost same for each colony but it becomes narrower in case of B-type, while using less number of insects. The rate of mortality was higher for non-B colonies (Pakistan and Spanish biotypes) in comparison with B-biotypes (Florida, USA, South Africa and Mexico).