As with people, insects suffer from viral infections. Many of these insect viruses occur naturally in the surrounding environment and some insect viruses from the family Baculoviridae (‘baculoviruses’) are known to be highly specific to individual species. For this reason they are likely to have a reduced impact on biodiversity and pose minimal risk to human health, and as such offer an alternative to chemical pesticides.
By focussing on the baculoviruses that infect migratory moth pests, my PhD aims to learn more about the link between insect movement (migration / dispersal) and disease. Currently we know very little about this area of research, yet it is particularly relevant because the use of microbial biopesticides is likely to grow due to European legislation limiting the use of chemical pesticides. As changes in climate and land use are likely to result in changing dispersal patterns of insect crop pests, it becomes ever more necessary to understand how such changes in dispersal could lead to changes in disease dynamics.
The system currently being studied is the African armyworm Spodoptera exempta and its baculovirus Spodoptera exempta nucleopolyhedrovirus (SpexNPV) (see here for more information). Using a combination of pathogen bioassays, qPCR and tethered flight mills, over the coming three years it is hoped that this system will give us further insight into:
- How different insect phenotypes and virus reproductive strategies might affect flight capacity in this migratory noctuid moth
- Whether or not the virus increases the propensity for migration
- How varying sublethal virus doses affect dispersal capacity and life history parameters
This project is funded by the BBSRC.
- The epidemiology of insect viruses
- Insect migration
- Behavioural ecology
PhD Working Title
The migration and disease ecology of lepidopteran crop pests
- Prof. Ken Wilson (Lancaster University)
- Dr. Jason Chapman (Rothamsted Research)
Work is conducted in the Insect and Parasite Ecology (iPEG) lab at Lancaster University and the Insect Migration and Spatial Ecology lab at Rothamsted Research:
For those wishing to learn more about current research in this area, a list of recommended reading is given below:
Chapman, Jason W., James R. Bell, Laura E. Burgin, Donald R. Reynolds, Lars B. Pettersson, Jane K. Hill, Michael B. Bonsall, and Jeremy A. Thomas. (2012). Seasonal migration to high latitudes results in major reproductive benefits in an insect. Proceedings of the National Academy of Sciences, 109 (37), 14924-14929. http://www.pnas.org/content/109/37/14924.abstract
Altizer, S., Bartel, R., & Han, B. A. (2011). Animal migration and infectious disease risk. science, 331 (6015), 296-302. http://www.sciencemag.org/content/331/6015/296.abstract
Chapman, J. W., Nesbit, R. L., Burgin, L. E., Reynolds, D. R., Smith, A. D., Middleton, D. R., & Hill, J. K. (2010). Flight orientation behaviors promote optimal migration trajectories in high-flying insects. Science, 327 (5966), 682-685. http://www.sciencemag.org/content/327/5966/682.abstract
Redman, E. M., Wilson, K., Grzywacz, D., & Cory, J. S. (2010). High levels of genetic diversity in< i> Spodoptera exempta</i> NPV from Tanzania. Journal of invertebrate pathology, 105 (2), 190-193. http://www.sciencedirect.com/science/article/pii/S0022201110001461
Vilaplana, L., Wilson, K., Redman, E. M., & Cory, J. S. (2010). Pathogen persistence in migratory insects: high levels of vertically-transmitted virus infection in field populations of the African armyworm. Evolutionary Ecology, 24 (1), 147-160. http://link.springer.com/article/10.1007%2Fs10682-009-9296-2