Rapid dispersal of Potato moth - Triggered by host plant switch?

The Guatemalan potato moth Tecia solanivora has since its discovery in 1973 become a most important invasive pest of potato in Central America and adjacent South American countries. In the field, larvae feed inside potato tubers in the soil. The moths also infest storage facilities in smaller farms, where potatoes must be protected with multiple insecticide sprays until consumption. Tecia solanivora has rapidly spread from Guatemala since the mid seventies. It attacks potato in the field and in storage. Control with neurotoxic and cancerogenous insecticides is not effective.

We study the hypothesis that a host switch, from a native solanaceous species to potato, which offers unlimited resources, has triggered the rapid dispersal of Guatemalan potato moth.

Insect herbivores use plant volatiles to recognize and to efficiently locate their host plants. Unequivocal proof for the role of host plant chemistry in host finding requires, of course, the identification of the chemicals which encode host recognition and which guide gravid females to oviposition sites.

This knowledge will also provide a basis for the development of innovative insect control methods. Behaviour-modifying are at advantage over insecticides, especially in Guatemalan potato moth. They enable behavioural manipulation of adult moths aboveground, and they are not toxic. Larvae of Guatemalan potato moth mining potato tubers in the soil are largely protected from insecicide sprays.

TV program about the pheromone project in Colombia (see UR).

Funding

This project is funded by SIDA

Personnel

Miriam Karlsson, Marie Bengtsson, Peter Witzgall

Collaboration

Alba Marina Cotes Prado, Felipe Bosa

Colombian Corporation of Agricultural Research (Corpoica), Colombia

Selected references

Bosa CF, Cotes AM, Bengtsson M, Fukumoto T, Witzgall P (2005) Pheromone-mediated mating disruption of Guatemalan potato moth Tecia solanivora Povolny (Lepidoptera: Gelechiidae). Entomol exp appl 114, 137-142

Bosa CF, Cotes AM, Osorio P, Fukumoto T, Bengtsson M, Witzgall P (2006) Disruption of pheromone communication in Tecia solanivora (Lepidoptera: Gelechiidae): flight tunnel and field studies. J econ Entomol 99, 1245-1250

Guatemalan potato moth

Povolny, D. 1973. Scrobipalpopsis solanivora sp. A new pest of potato (Solanum tuberosum) from Central America. Acta Universitatia Agriculturae, Faculta Agronomica. 21: 133-146.