PHENOTYPIC RESPONSE OF 2 SUCCESSIVE GYPSY-MOTH (LEPIDOPTERA, LYMANTRIIDAE) GENERATIONS TO ENVIRONMENT AND DIET IN THE LABORATORY

A 2-generation comparison documented variables affecting performance o f gypsy moth, Lymantria dispar (L.), reared under laboratory condition s, including differences in environment (different locations), substra ins (isolated over time), and diet (preparation and ingredients) Gypsy moth colonies have experienced unpredicted periods of poor hatch, red uced survival, and slow asynchronous development that have collectivel y been called abnormal performance syndrome (APS). Substrain differenc es were found but were not linked to the expression of APS. Parental r earing environment affects development and survival of larvae of both the parent and progeny generations, but only influences the degree of expression of APS. The expression of APS results from a dietary proble m; sensitivity varies within and between families. In addition, the ph enotype of the individual (whether it expresses APS or not) appears to depend not only on its own genotype hut on the interaction between it s parent genotypes and the diet they fed upon. The importance of these findings for laboratory reared insects in general are discussed.