| Abstract: | Abstract. Male stink bugs, Euschistus heros , only produce the three-component sex pheromone blend consisting of methyl-(2 E ,4 Z )-decadienoate, methyl-2,4,6-trimethyldodecanoate and methyl-2,4,6-trimethyltridecanoate in a constant ratio of 53 : 3 : 44, respectively, when provided with a food source (green beans, Phaseolus vulgaris ). When volatiles are collected from insects with drinking water, humidified air, or under dry conditions, the insects stop producing two components (methyl-2,4,6-trimethyldodecanoate and methyl-2,4,6-trimethyltridecanoate) after 1 day and increase the amount of defensive compounds produced e.g. ( E )-2-hexenal, decane]. Methyl-2,4,6-trimethyltridecanoate is able to change the behaviour of females but not males. Dual-choice olfactometer bioassays with synthetic standards of all three components, as well as the ternary mixture in the correct ratio, induce a response from females but not males, indicating that all three components have a role in sexual communication. Thus, the dietary conditions under which volatile collections are carried out are crucial for determination of the precise sex pheromone blend. |
