The major areas of my research interest are applied insect ecology, insect behavior, and integrated pest management. More specifically, I am interested in a variety of topics related to the dynamics and regulation of herbivorous insect populations, including interactions with host plants, natural enemies, cultural practices, and insecticides. I am also interested in more theoretical aspects of invasion biology, with an emphasis on the ecology of exotic organisms deliberately introduced to a new location by humans.
Presently, humans posses a vast arsenal of different pest control techniques, ranging from synthetic insecticides to natural enemies, and from transgenic plants to quarantine regulations. What is lacking, however, is a good understanding of the ecological consequences of their implementation for both target and non-target organisms. When a particular action is taken, whether it is an insecticide application, planting of a transgenic cultivar, or release of a biological control agent, it is imperative that we can forecast the sequence(s) of events it might trigger.
Limited-scale toxicological and host-range assays, still commonly used for decision-making, often do not reflect actual developments in the field. Therefore, a more sophisticated approach, which takes into account an intricate web of cause-and-effect events within a given ecosystem, is required to achieve a long-term success both in pest control, as well as in conservation of beneficial organisms.
Most ecological systems are very complex, and their good understanding is extremely difficult. However, sustainable development of the human civilization is hardly possible without such an understanding. As a scientist, I hope that my research will contribute to building a knowledge-based foundation for predicting effects of human intervention in insect communities.
To get an idea of the type of research conducted in our laboratory, please look through our publications. Electronic or paper reprints are available upon request.
Currently, there are five active research projects going on in our laboratory.
- Evolution and management of insecticide resistance in the Colorado potato beetle. Colorado potato beetle is infamos for its remarkable ability to develop resistance to virtually every chemical that has ever been used against it. In some cases, a new insecticide failed after one year (e.g., endrin) or even during the first year of use. Impressive potential to withstand a variety of poisons is probably caused by the coevolution of the beetle and its host plants in the family Solanaceae, which have high concentrations of phytotoxins in their foliage. It is also aided by the high fecundity of this species, with a single mutant potentially producing several hundred offspring in just one generation. We are investigating behavioral ecology and population genetics of this insect in an attempt to come up with management approaches allowing to extend the useful life of commercially used insecticides.
Representative Publications:
- Alyokhin, A., M. Baker, D. Mota-Sanchez, G. Dively, and E. Grafius. 2008. Colorado potato beetle resistance to insecticides. American Journal of Potato Research 85: 395–413. (Invited review article). [Full Text]
- Alyokhin, A., G. Dively, M. Patterson, C. Castaldo, D. Rogers, M. Mahoney, and J. Wollam. 2007. Resistance and cross-resistance to imidacloprid and thiamethoxam in the Colorado potato beetle. Pest Management Science 63: 32-41. [E-mail to request a reprint]
- Baker, M. B., A. Alyokhin, A. H. Porter, D. N. Ferro, S. R. Dastur , and N. Galal. 2007. Persistence and inheritance of costs of resistance to imidacloprid in Colorado potato beetle. Journal of Economic Entomology 100: 1871-1879. [Full Text]
- Plant-mediated effects of soil management practices on the Colorado potato beetle. Plants grown on organically managed soils fertilized with compost and manure have been shown to be less favorable hosts for phytophagous insects than plants grown on conventionally managed soils fertilized with synthetic fertilizers. Dr. Phelan form the Ohio State University suggested that the organic matter and microbial activity associated with organically managed soils afford a buffering capability to maintain nutrient balance in plants. Over the centuries, plants were evolving on soils amended with natural equivalents of manure and compost. As a result, they developed ability to utilize available nutrients to achieve the most favorable equilibrium between growth, reproduction, and defense against insect herbivores. Using synthetic fertilizers may shift this balance towards growth and reproduction, while compromising defense capabilities of affected plants. We have detected consistently lower Colorado potato beetel densities in plots with a history of receiving organic soil amendments. Unlike beetle abundance, plant height and canopy cover were comparable between plots receiving manure and synthetic fertilizer. Furthermore, tuber yields were higher in manure-amended plots. In direct accordance with the mineral balance hypothesis, there was a dramatic dissimilarity in the mineral composition of potato leaves collected from manure-amended and synthetically fertilized plots. Currently, we are investigating mechanisms of the observed reduction in beetle densities.
Representative Publications:
- Alyokhin, A. and R. Atlihan. 2005. Reduced fitness of the Colorado potato beetle (Coleoptera: Chrysomelidae) on potato plants grown in manure-amended soil. Environmental Entomology 34: 963-968. [Full Text]
- Alyokhin, A., G. Porter, E. Groden, and F. Drummond. 2005. Colorado potato beetle response to soil amendments: a case in support of the mineral balance hypothesis? Agriculture, Ecosystems, and Environment 109: 234-244. [Full Text]
- Ecology and behavior of potato-colonizing aphids. Potato aphid (Macrosiphum euphorbiae (Thomas)), buckthorn aphid (Aphis nasturtii Kaltenbach), and green peach aphid (Myzus persicae (Sulzer)) commonly colonize potato plants (Solanum tuberosum L.) in Northeastern U.S. and Canada. Populations of these insects seldom reach densities sufficient for causing noticeable crop injury by sap feeding. However, their ability to transmit plant viruses is an ominous threat to commercial potato production. Currently, most pest management decisions are made based on the aphid abundance and/or on the proportion of aphid-infested plants. Aphid populations are being suppressed with synthetic insecticides, often at a considerable cost to potato growers and to the environment. However, if aphids feed on the same plant for their entire life, even relatively high populations will not result in significant virus transmission. Alternatively, even a small population of highly mobile aphids can infect a large number of potato plants. We investigate biotic and abiotic factors affecting fluctuations in aphid populations and their movement between potato plants. Our ultimate goals are (1) to develop control techniques that complement or enhance natural forces in restraining the growth of aphid populations; and (2) to acquire an ability to specifically target viruliferous aphids moving between the plants.
Representative Publications:
- Narayandas, G. and A. Alyokhin. 2006. Interplant movement of potato aphid (Homoptera: Aphididae) in response to environmental stimuli. Environmental Entomology 35: 733-739. [Full Text]
- Alyokhin, A., F. A. Drummond, and G. Sewell. 2005. Density-dependent regulation in populations of potato-colonizing aphids. Population Ecology 47: 257-266. [Full Text]
- Alyokhin, A. and G. Sewell. 2003. On-soil movement and plant colonization by walking wingless morphs of three aphid species (Homoptera: Aphididae) in greenhouse arenas. Environmental Entomology 32: 1393-1398. [Full Text]
