Biochemistry of Insect Pheromones: Pathways, Regulation and Applications in Chemical Ecology

Pheromones are chemical compounds released by an organism that function similarly to external hormones, influencing the behavior of other individuals of the same species. The initial identification of an insect sex pheromone, bombykol [(E,Z)-10,12-hexadecadien-1-ol], came from the silkworm moth Bombyx mori (Butenandt et al., 1959). The first pheromone linked to an insect pest, gyplure [(Z)-18-hydroxyoctadec-9-en-7-yl acetate], was synthesized from ricinoleic acid for the gypsy moth (Jacobson et al., 1964). Subsequently, (Z)-7-dodecenyl acetate was recognized as the sex pheromone for the cabbage looper Trichoplusia ni (Berger, 1966). In the bark beetle Ips paraconfusus, terpenoid alcohols such as ipsenol, ipsdienol, and verbenol serve as pheromones. By the 1980s, research revealed that pheromone diversity arises from fatty acid and isoprenoid pathway derivatives, modified by specialized enzymes (Bjostad et al., 1987; Jurenka, 2003). In honeybees, queen pheromones result from specific fatty acid chain modifications. In species like cockroaches and beetles, juvenile hormone controls both pheromone synthesis and ovarian development. Nutritional factors, particularly sugar metabolism, play a significant role in regulating pheromone levels in moths and cockroaches (Foster, 2009). Future pest control strategies may leverage sterile-male release techniques to interfere with pest reproduction.