Electroantennogram Responses of the Male Moth, Argyrotaenia Velutinana to Mixtures of Sex Pheromone Components of the Female

Electroantennogram (EAG) responses were recorded from male redbanded leafroller moth, Argyrotaenia velutinana, antennae using mixtures of the three female-produced sex pheromone components: cis-11-tetradecenyl acetate, trans-11-tetradecenyl acetate, and dodecyl acetate (12:Ac) Binary mixtures containing 3%, 8%, and 15% trans in cis elicited significantly higher amplitude responses than othei isomeric mixtures as well as pure ci,s and trans alone The higher responses to such mixtures were less than additive at high dosages and additive at lower dosages, Receptor adaptation studies using the two isomers support a previous single unit study demonstrating the presence of a t least two functionally different receptor sites on male A velutinana antennae; adaptation to an airstream containing one isomer did not eliminate response to the opposite isomer presented concuhently An airstream containing the third component, 12:Ac, caused a significant slowing of the recovery rate during the entire recovery period of EAG responses to cis but not trans, suggesting that a possible temporal modulation of neuronal response by 12:Ac may be a means of coding for this component by antennal sensory neurons THE REDBANDED leafroller moth, Argyrotaenia velutinana (Walker), responds to a female-produced sex pheromone comprised of three components (ROELOFS et a1 , 1975) The primary sex pheromone component of A velutinana was identified as cis-11-tetradecenyl acetate (cll-14:Ac) (ROELOFS and ARN, 1968) Two other pheromone components, trans-11-tetradecenyl acetate (tll-14:Ac) and dodecyl acetate (12:Ac) were shown to be instrumental in increasing the trap catch of male A velutinana in the field The former was shown to be necessary for attractancy when present in low ratios to the cis isomer and gave optimum attractancy when mixed in a trans:cis ratio of approximately 7:93 (KLUN et al , 1973; ROELOFS et al , 1975) At ratios higher than 7:93, trap catch of males was reduced Dodecyl acetate was found to increase trap catch of A velutinana males in field tests when evaporated with the other two components (ROELOFS and COMEAU, 1968, 1971a) Further tests showed that optimum attractancy was obtained with the addition of 12:Ac at ratios greater than 3:2 to the trans:cis (8:92) blend (ROELOFS et a1 , 1975) All three pheromone components were isolated and identified from female A velutinana abdominal tip extract or calling female effluvia (ROELOFS et a / , 1975) The trans:cis ratio was found to be present in a ratio of about