Submitted to: 2000 Proceedings Washington State Potato Conference
Publication Type: Proceedings
Publication Acceptance Date: 6/20/2000
Publication Date: 6/20/2000
Citation: Lacey, L.A., Horton, D.R. 2000. The potential for insect pathogens as control agents of pest insects of potato. Proceedings Washington State Potato Conference. 85-87. Interpretive Summary: Our research at the Yakima Agricultural Research Laboratory in 1997-1999 was focused on evaluation of Bt and B. bassiana when used individually and as mixtures and alternations under irrigated desert conditions. Our current efforts are focused on development of insect pathogens for control of the green peach aphid (GPA) and wireworms. The only pathogen group that has been developed for control of aphids are fungi. Under certain conditions, natural outbreaks of fungi have resulted in spectacular crashes in aphid populations. This points out the need to interfere with the activity of naturally occurring fungal pathogens of aphids. Wireworms will provide a challenging goal for development of microbial control agents. For the soil habitat of wireworm larvae, fungi offer the most potential for development. Microbial control agents can be effective and serve as alternatives to broad spectrum chemical insecticides in the potato agroecosystem.
Technical Abstract: Insect diseases are important natural regulatory factors in many insect populations. Many species of the pathogens that cause disease in insects are also employed as biological control agents of insect pests in row and glasshouse crops, orchards, ornamentals, range, turf and lawn, stored products, and forestry and for control of pest and vector insects of veterinary and medical importance. The comparison of entomopathogens with conventional chemical pesticides is usually solely from the perspective of their efficacy and cost. In addition to efficacy, the advantages of using microbial control agents are numerous. These include safety for humans and other nontarget organisms, reduction of pesticide residues in food, preservation of other natural enemies and increased biodiversity in managed ecosystems. As with predators and parasitoids, there are three basic approaches for using entomopathogens as microbial control agents (classical biological control, augmentation, and conservation). Most examples of microbial control involve inundative application of entomopathogens. This is especially true for the most widely used microbial control agent in the bacterium, Bacillus thuringiensis (Bt). The discovery of new varieties with activity against larvae of moths, beetles and certain has enhanced the utility of this agent.