Is host selection in leafminer adults influenced by pre-imaginal or early adult experience?

Olfactometer and feeding/oviposition preference tests were carried out to study if host plant preference in two agromyzid leafminers, Liriomyza trifolii and Liriomyza huidobrensis, is influenced by pre-imaginal or imaginal experience, and at what level (host plant species, host plant variety or host age). It was found that the choice of host plant species (potato or tomato) and host plant variety had a pre-imaginal component, which could be reinforced (or modified) by an imaginal component. On the other hand, preference for potato leaves of different ages did not appear to be based on either pre-imaginal or imaginal factors, but resulted from differential performance and oviposition preference. The Hopkins' host selection principle appears to operate in these leafminers at the level of host species, and to some extent at the level of host variety, but not with respect to host age.