Identification of a sex pheromone component of Pseudococcus cryptus

A sex pheromone component of Pseudococcus cryptus has been isolated and identified. The crude pheromone extract obtained by airborne collection was fractionated by liquid chromatography (LC) on Florisil, and further purified by high performance liquid chromatography and preparative Gas Chromatography (GC). The pheromone component was shown to be an ester, the alcohol part of which was identical to the known alcohol moiety of the pheromone of Planococcus citri. The chemical structure was determined to be 3-isopropenyl-2,2-dimethylcyclobutylmethyl 3-methyl-3-butenoate by MS and ¹H NMR analyses. The absolute configuration of the pheromone was assigned as (1R,3R) by comparison of the retention time of the alcohol derived from the P. cryptus pheromone with those of the alcohol derived from P. citri pheromone, and a synthetic sample of alcohol enriched in the (1R,3R)-enantiomer, using a chiral GC stationary phase. The structure of the pheromone was confirmed by synthesis, and by bioassays in a glasshouse.