2010 Annual Report
1a.Objectives (from AD-416)
Elucidate the chemical mechanisms that govern insect behavior and the interactions of insects with other organisms in the environment so that new biologically rational, environmentally safe methods may be developed to manage insect pests.
1b.Approach (from AD-416)
Identify and evaluate chemicals that regulate behaviors, including foraging, mating and oviposition of economically important beneficial and pests insects. Determine physiological and biochemical mechanisms, elicitors, and regulators involved in the interactions of plants with insect herbivores and their natural enemies. Determine endogenous and exogenous mechanisms that coordinate development of reproductive competence with sexual signaling in insects, including neurochemical regulation of pheromone byiosynthesis. The major target insects for this research will include fruit, vegetable, and field crop pests in the Lepidopteran families, Noctuidae, Pyralidae and Sphingidae as well as Tephritid fruit flies and selected Coleopteran species. Other target insects may be selected as needed as the project progresses.
Small hive beetles are important pests of the apiculture industry but the biology of the pest is poorly understood. Behavioral studies were conducted to determine if light modulates behavior. Among wavelengths across the visible and near UV spectrum we found that SHB larvae and adults are most attracted to the 390nm wavelength. Based on this discovery a new high efficiency trapping system for the small hive beetle larvae was developed using light was developed. The discovery will allow for effective mass trapping of larvae in honey houses.
Behavioral analysis of responses of Varroa mites to larvae of the honeybee in the presence or absence of high concentrations of chemicals known to attract the mites to brood were conducted in laboratory studies. Results of these assays demonstrated that release of large amounts of the chemicals effectively confused the mites so that they could not infiltrate larval cells. The discovery is of importance for non-pesticide control of the mite.
Studies on development of methods to provide methoprene plus protein to sterile adult Tephritid fruit flies used to control outbreaks in Sterile Insect Technique programs (SIT) resulted in a practical method in which a slurry of methporene, protein and sugar in water is painted on card and provided as food to males prior to release. The method accelerated reproductive development by males by 4 or more days. This method has been adopted by Mosca Fruit Mexico and is used for all SIT programs to control the Mexican Fruit fly in Mexico.
With a global shift in soybean production to the tropics, the velvetbean caterpillar has emerged as the most significant defoliating pest of this crop. We conducted studies using a cowpea-velvetbean caterpillar model to determine how the pest overcomes plant defenses and that caterpillars minimize induced plant defenses by converting the plants own pest recognition signal into an inhibitor of production of plant defensive compounds. Based on this we redesigned the plant protein responsible for the activation of defense and recovered both a functional signal and greater defense responses following attack by these caterpillars. This has significance for development of plants resistant to velvetbean caterpillar attack.
This project has expired and been replaced by project #6615-22430-004-00D.
Elucidating the chemistry of host finding by the Varroa mite. The Varroa mite is the most important pest of the honeybee industry in the world and no highly effective control strategy exists for this pest. In order to develop a non-pesticide approach to control of the Varroa mite we investigated the semiochemical communication system used by the mite to invade honeybee larval cells. We identified two chemicals that effectively cause mites to be attracted into empty rearing cells. Identification of these compounds allowed us to conduct atmospheric flooding experiments in which large amounts of the compounds were released into bee hive frames. In this study we determined that the mites were confused by the large amounts of chemicals and unable to find larvae on which to feed. Additionally we saw no significant effect on bee behavior. When developed this confusion technology will have a significant impact on controlling Varroa mites in bee hives.
Recovery of plant defense against insect attack. With a global shift in soybean production to the tropics, the velvetbean caterpillar has emerged as the most significant defoliating pest of this crop. Using cowpea as a legume model, we discovered that velvetbean caterpillars minimize induced plant defenses by converting the plants own pest recognition signal into an inactive competitive inhibitor of self-defense activation. We redesigned the plant protein sequence responsible for the activation of defense and recovered both a functional signal and greater defense responses following attack by these caterpillars. Discovery of the mechanisms pests use to overrun crop plants can serve as essential information to engineer improved plant protection. The loss of crop plant resistance to insect pests and pathogens is a significant problem and major treat to U.S. agriculture. This work represents a positive impact on agriculture by identifying entirely new tools and strategies for recovering plant resistance and combating crop pests.
Development of light based trapping systems for small hive beetles. The small hive beetle is an important pest for the apiculture industry and is particularly problematic in honey houses which are commonly near bee holding yards. No pesticides are registered for use on hive beetles in these areas. We investigated the effects of light on attraction of both adult and larvae and determined that both were strongly attracted to light at 390nm. Based on this we conducted shed trapping studies using previously developed adult traps and a new trap for larvae. We captured 1/3 of all adults released and 75% of larvae released in these studies. These trapping systems will have a significant positive impact on improving viability of the $14 billion/year apiculture and pollination industries in the United States.
5.Significant Activities that Support Special Target Populations
Research on developing strategies for control of small hive beetles and Varroa mites targets small farms (60%) of beekeepers fall into this category.
Torto, B., Fombong, A.T., Mutyambai, D.M., Muli, E., Arbogast, R.T., Teal, P.E. 2010. Aethina tumida (Coleoptera: Nitidulidae) and Oplostomus haroldi (Coleoptera: Scarabaeidae): Occurrence in Kenya, Distribution within Honey Bee Colonies, and Response to Host Odors. Annals of the Entomological Society of America. 103(3):389-396.
Tieman, D., Zeigler, M., Schmelz, E.A., Taylor, M.G., Rushing, S., Jones, J.B., Klee, H.J. 2010. Functional analysis of a tomato salicylic acid methyl transferase and its role in synthesis of the flavor volatile methyl salicylate. Plant Journal. 62:133-123.
Yoshinaga, N., Alborn, H.T., Nakanishi, T., Suckling, D.M., Nishida, R., Tumlinson, J.H., Mori, N. 2010. Fatty acid-amino acid conjugates diversification in Lepidopteran caterpillars. Journal of Chemical Ecology. 36:319-325.
Haq, I., Caceres, C., Henrrichs, J., Teal, P.E., Wornoayporn, Stauffer, C., Robinson, A. 2010. Methoprene modulates the effect of diet on male melon fly, Bactrocera cucurbitate, performance at mating aggregations. Entomologia Experimentalis et Applicata. 136:21-30.
Pereira, R., Sivinski, J.M., Teal, P.E. 2010. Influence of a juvenile hormone analog and dietary protein on male Anastrepha suspensa (Diptera:Tephritidae) sexual success. Journal of Economic Entomology. 103(1): 40-46.
Jones, D., Jones, G., Teal, P.E., Hammac, C., Messmer, L., Osborne, K., Belgacem, Y.H., Martin, J. 2010. Suppressed production of methyl farnesoid hormones yields developmental defects and lethality in Drosophila larvae. General and Comparative Endocrinology. 165:244-254.
Arbogast, R.T., Torto, B., Teal, P.E. 2010. Potential for population growth of the small hive beetle Aethina Tumida (Coleoptera: Nitidulidae) on diets of pollen dough and orange. Florida Entomologist. 93(2):224-230