Sex Pheromone Biosynthesis in the Tortricid Moth, Ctenopseustis herana (Felder & Rogenhofer)

Abstract

Biosynthesis of the unusual sex pheromone component (Z)-5-tetradecenyl acetate (25-14:OAc) was studied in the tortricid moth, Ctenopseustis herana (Felder & Rogenhofer), by fatty acid methyl ester (FAME) analysis of the pheromone gland, and topical application of various deuterium-labelled acids to the gland. The only unusual unsaturated FAME found in base-methanolyzed glands of females was the putative precursor of the pheromone, methyl (Z)-5-tetradecenoate (Z5-14:Me). When deuterium-labelled, myristic, palmitic, stearic, lauric, and oleic acids were applied to the gland, label was incorporated into the pheromone component only from the first three acids (i.e., Z5-14:OAc could not be biosynthesized from lauric or oleic acids). Furthermore, the amount of label incorporated from the first three acids decreased in the order myristic > palmitic > stearic. Application of labelled myristic acid to the gland resulted in incorporation of label into Z5-14:Me. These data are consistent with the biosynthesis of Z5-14:OAc in C. herana resulting from Δ5-desaturation of myristic acid, a novel biosynthetic route for a moth sex pheromone component. Regulation of pheromone biosynthesis in this species was also investigated. Decapitation of female C. herana resulted in a significant decline in sex pheromone titre. Injection of female head extract or synthetic Bombyx mon pheromone biosynthesis-activating neuropeptide (PBAN) into decapitated female C. herana gave a significant increase in pheromone titre, suggesting that pheromone biosynthesis in this species is regulated by a PBAN or PBAN-like substance. © 1996 Wiley-Liss, Inc.