Abstract:

Interactions between vector insects, plant viruses and host plants are complex and diverse. Although much work has been done to study the tripartite relationships, their roles in biological invasions have been rarely explored. The limited case studies available indicate that the interactions may be mediated by the host plant susceptibility to viruses, the suitability of host plants to vector insects, and the insects’ capacity to utilize host plants. When a host plant is highly susceptible to the virus but shows a low level of suitability to the insect, and the insect has a strong capacity to use different host plants, an indirect mutualistic relationship is likely to occur between vector insect and plant virus via their shared host plants. This kind of mutualism can contribute to the widespread invasion of vector insects as well as the epidemics of plant viruses. In view of the significance of the tripartite interactions in biological invasions, future effort should be made to investigate comparatively many more combinations of different species, and various technologies can be used to reveal the physiological and molecular mechanisms of the interactions.

Key words: vector insect, plant virus, plant, indirect mutualism, biological invasion