Sex pheromone ofEupoecilia ambiguella female: Analysis and male response to ternary blend

Abstract

Sex gland extracts and washes ofEupoecilia ambiguella contain 10-20 ng/female of the primary sex pheromone componentZ-9-dodecenyl acetate (Z9-12∶Ac), accompanied by a number of related compounds. These areE-9-dodecenyl acetate (E9-12∶Ac),Z-9-dodecen-1-ol (Z9-12∶OH), saturated acetates of 12, 16, 18, and 20 carbons, and traces of a doubly unsaturated acetate, tentatively identified as a 9,11-dodecadienyl acetate. Octadecyl acetate predominates among the pheromone-related components, making up 1-2, occasionally 20-30 times the amount ofZ9-12∶Ac. The same compounds were also found in field-collected females and in effluvia.Z-9-Undecenyl acetate, which is a male attractant on its own, was also found in a sample of female effluvia. A hierarchy is observed in the ethological function of the pheromone components.Z9-12∶Ac is an attractant forE. ambiguella males. Dodecyl acetate (12∶Ac) is not attractive on its own but augments male catch when added to the main attractant. Addition of 18∶Ac augments attraction only when bothZ9-12∶Ac and 12∶Ac are present. Windtunnel tests demonstrate that 18∶Ac also raises the disorientation threshold, as previously shown for 12∶Ac. Other compounds, with the possible exception of additional saturated acetates, had either no effect on trap catch or, in the case ofE9-12∶Ac,Z9-12∶OH, andE-9,11-dodecadienyl acetate, were inhibitory above a certain level. A blend of roughly equal parts ofZ9-12∶Ac, 12∶Ac, and 18∶Ac provides the best attractant blend forE. ambiguella known to date.