The notorius 'B'-biotype whitefly, Bemisia tabaci, can act as a vector for viruses, transmitting them between plants as it feeds. Nothing new there? Yes actually, in an interesting twist, researchers at Zhejiang University, China have found that certain viruses repay the favour by increasing whitefly performance on the infected plant.
Comparisons of B whitefly fecundity on Tobacco curly shoot virus (TbCSV) and Tomato yellow leaf curl China virus (TYLCCNV) infected tobacco plants against fecundity on uninfected plants showed increases of 12 and 18 fold respectively. Longevity increased by 6 and 7 fold respectively. By contrast, a whitefly native to China show no performance differences between the plants.
"...mutualism between the B whitefly and the viruses may contribute to the ability of the B whitefly to both invade and displace indigenous whiteflies, as well as causing disease pandemics of the viruses associated with this vector," said Prof. Shu-Sheng Liu, one of the study authors. The team go on to suggest that this kind of mutualistic relationship could be a factor behind the success of other invasive organisms.
There are literally thousands of articles on the hosts and biology of B. tabaci in the CAB Abstracts database. If you're subscribed, then dive straight in through this link. If not, then you can still follow the link to the published article here.