|Leal, Walter - UC DAVIS|
|Parra-Pedrazzoli, A - UC DAVIS|
|Pesak, Douglas - MAX-PLANK INSTITUT|
|Kaissling, Karl-Ernst - UC DAVIS|
|Morgan, Tania - UC DAVIS|
|Dundulis, Edward - UC DAVIS|
|Higbee, Bradley - PARAMOUNT FARMING|
|Zalom, Frank - UC DAVIS|
Submitted to: Naturwissenschaften
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 19, 2004
Publication Date: January 25, 2005
Citation: Leal, W.S., Parra-Pedrazzoli, A.L., Pesak, D.J., Kaissling, K., Morgan, T.I., Dundulis, E.A., Burks, C.S., Higbee, B.S., Zalom, F.G. 2005. Unusual pheromone chemistry in the navel orangeworm: novel sex attractants and a behavioral antagonist. Naturwissenschaften. 92(3):139-146 Interpretive Summary: The navel orangeworm, Amyelois transitella Walker (Lepidoptera: Pyralidae) (NOW), is a primary pest of almonds, pistachios, walnuts and figs; crops collectively worth over a billion dollars annually to California producers. The primary component of the NOW sex pheromone was identified in 1979, but this component by itself is not sufficient to bring males to a point source such as a lure. A combined molecular and sensory physiology approach was used to identify 6 additional components, 2 of them never before observed in insect sex pheromones. Field assays showed that, when combined, these components were as attractive to male NOW as unmated females. This discovery will greatly improve tools for monitoring NOW, and may improve the efficacy of mating disruption.
Technical Abstract: Using molecular- and sensory physiology-based approaches, three novel natural products, a simple ester, and a behavioral antagonist have been identified from the pheromone gland of the navel orangeworm, Amyelois transitella Walker (Lepidoptera: Pyralidae). In addition to the previously identified (Z,Z)-11,13-hexadecadienal, the pheromone blend is comprised of (Z,Z,Z,Z,Z)-3,6,9,12,15-tricosapentaene, (Z,Z,Z,Z,Z)-3,6,9,12,15-pentacosapentaene, ethyl palmitate, ethyl (Z,Z)-11,13-hexadecadienoate, and (Z,Z)-11,13-hexadecadien-1-yl acetate. The C23 and C25 pentaenes are not only novel sex pheromones, but also new natural products. In field tests, catches of A. transitella males in traps baited with the full mixture of pheromones were as high as thos in traps with virgin females, whereas control and traps baited only with the previously known constituent did not capture any moths at all. The navel orangeworm sex pheromone is also an attractant for the meal moth, Pyralis farinalis L. (Pyralidae), but (Z,Z)-11,13-hexadecadien-1-yl acetate is a behavioral antagonist. The new pheromone blend may be highly effective in mating disruption and monitoring programs.