Stink bugs are pests which attack several economically important crops, including cotton, soybeans, pecans, plums and okra. Although a variety of chemical pesticides have been used in the past to control stink bugs, there are serious disadvantages in these pesticides. Some pesticides pollute the environment while others are toxic to humans. Such environmental and consumer safety concerns have led to the deregistration of many pesticides. Also, there is generally a reluctance to use any pesticides on agricultural products which are consumed as food. Therefore, eliminating, or at least reducing the amount of toxic pesticides used in the management of insect pests is desirable. Consequently, scientists have pursued the development of alternative pest control agents that are safer for the environment and for consumers. Among such alternative control agents are insect sex pheromones.
Many insects communicate by releasing volatile pheromones. Sex pheromones, for example, are typically released by one sex at appropriate times to attract the other sex of the same species. This phenomenon has been exploited to trap the insects of one sex and kill them, thereby preventing mating and reducing the insect population in following generations. Pheromones have been used in this way on a commercial basis for several years, and provide effective control of numerous insect pest species. For stink bugs, the ability to control the population was improved by the identification of the pheromone, methyl (2E,4Z)-decadienoate (Aldrich et al. Environ. Entomol. 20:477-483, 1991).
Although the use of pheromones is advantageous, most pheromones are artificially synthesized, and thus are very expensive. As a result, pest control or pest management using synthetic pheromones is not always cost efficient. In some cases, naturally occurring and less-expensive compounds can be identified that act as synergists to synthetic pheromones. For example, eugenol, a naturally occurring compound, has been identified as a synergist and is used with the synthetic pheromone, grandlure, for capturing and controlling cotton boll weevils. The naturally-occurring compound adds to the attractant effect of the grandlure (McKibben et al., U.S. Pat. No. 6,183,733).
To date, no such synergists, have been identified for pheromones of stink bugs. Accordingly, there exists a need to identify synergists for stink bug pheromones and develop less-expensive attractant formulations.