|Nachman, Ronald - Ron|
Submitted to: Journal of Insect Behavior
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/15/2007
Publication Date: 7/19/2007
Citation: Downer, K., Nachman, R.J., Stoffolano, J. 2007. Factors affecting engorgement behavior in the salt marsh horse fly, Tabanus nigrovittatus Macquart (Diptera: Tabanidae). Journal of Insect Behavior. 20:403-412. Interpretive Summary: Because of problems with the development of resistance to conventional pesticides, there is a critical need for new concepts and alternative approaches in controlling insect pests. The basic premise of this research is that neuropeptides (short chains of amino acids) serve as potent messengers in insects to regulate vital functions. New, selective control measures may be developed by designing metabolically stable mimics of these neuropeptides that actively inhibit or over-stimulate functions regulated by them, resulting in disruption of the internal environment of the insect. We report on a finding that the feeding inhibition activity of the sulfakinin neuropeptide class in the salt marsh horse fly is dependent on the feeding technique used. A deeper understanding of how these neuropeptides regulate the critical processes of satiety and digestion in insects will aid in the design of strategies to disrupt insect populations. The above results suggest that development of metabolically stable versions of the sulfakinins could lead to agents capable of disrupting the feeding process in insect pests. The work brings us one step closer to the development of practical neuropeptide-like substances that will be effective in controlling pest insects in an environmentally friendly fashion.
Technical Abstract: Female Tabanus nigrovittatus were field collected and used in laboratory experimentation to further elucidate the physiological and behavioral factors that affect engorgement. Previous studies have shown that sulfakinins are feeding satiety factors in invertebrates. This study demonstrates that sulfakinins have differing effects on engorgement that is dependent on the type of feeding technique used in the laboratory. The satiety effect and the percentage of flies engorging using the blood-soaked Kimwipe feeding technique is not in agreement with previous experiments using artificial membranes. This study is also the first to demonstrate that the temperature of blood is a significant factor in engorgement in this species. Also found that the percentage of flies engorging is significantly different depending on the feeding technique used.