Fatty acyl pheromone precursors in the sex pheromone gland of female tobacco hornworm moths, Manduca sexta (L.)

The total fatty acyl composition, including free fatty acids and fatty acyl moieties in lipids, of sex pheromone glands and selected other body tissues of Manduca sextra females was determined by capillary gas chromatographic and mass spectroscopic analysis. Fatty acyl analogs of eleven pheromone aldehydes were found in the epidermal cells of the pheromone gland. While the common fatty acyl groups, hexadecanoate, (Z)-9-hexadecenoate, octadecanoate, (Z)-9-octadecenoate, (Z,Z)-9,12-octadecadienoate and (Z,Z,Z)-9,12,15-octadecatrienoate, were detected in other body tissues of females as well as in the epidermal cells and cuticle of the pheromone gland, uncommon fatty acid pheromone analogs were not found in significant amounts in tissues other than the epidermal cells of the pheromone gland. Quantitative analysis of extracts revealed that the fatty acyl analogs of pheromone aldehydes were present continuously in pheromone glands of females from about 3 or 4 days prior to eclosion from the pupal stage until the adults were 8 days old. While injection of pheromone biosynthesis activating neuropeptide into the abdomen of the females at any age, even in the late pupal stage, resulted in pheromone production, the quantities of the bound fatty acyl components in the pheromone gland were not measurably changed.