|Duncan, Larry -|
Submitted to: Citrus Industry
Publication Type: Popular Publication
Publication Acceptance Date: June 1, 2009
Publication Date: June 14, 2009
Citation: Lapointe, S.L., Duncan, L. 2009. Update on Diaprepes research at USHRL. Southeast Agent Radio Program. Citrus Industry. http://southeastagnet.com/?s=diaprepes Technical Abstract: A 6-tunnel wind tunnel was constructed to study behavior of adult Diaprepes abbreviatus. Weevils were introduced downwind and allowed to move upwind in response to odor sources (targets). Weevils did not respond in empty tunnels (no odor). Some movement upwind but no arrestment (cessation of movement) occurred when weevils were presented with young citrus leaves (flush). Citrus flush fed upon by D. abbreviatus was highly attractive and caused attraction and arrestment of male and female Diaprepes. The effect was duplicated by placing organdy-enclosed feces (frass) sachets on undamaged citrus flush. Arrestment was eliminated when fed-upon flush was enclosed so weevils could not contact leaves. In these experiments, weevils continued to move upwind. Thus, host and mate location by D. abbreviatus are mediated by both airborne odors and contact semiochemicals. This information will be essential for development of a trap. Through use of GC/EAD we have identified a compound(s) that elicits a large antennal response at low concentrations. It was produced only by males and 6-wk-old males produced more compared with 2-wk-old males. The compound's structure remains elusive but appears to be completely novel. We are currently attempting to identify the structure and will proceed to study how it affects behavior and how it can be used to monitor or control Diaprepes.