DEVELOPMENT OF NEODIPRION-SERTIFER (GEOFF) (HYM, DIPRIONIDAE) ON DROUGHT-STRESSED PINES - A LABORATORY EXPERIMENT

Potted Scots pine plants with a severely reduced water supply were use d as food plants for Neodiprion sertifer. N. sertifer larvae remained caged on the plants from larval hatching to cocoon spinning. The treat ment accelerated larval development and increased adult size, compared to insects on well-watered controls. Larval mortality tended to be lo wer in stressed trees, but seemed partly determined by genetic factors . Such factors appeared to be of minor significance for developmental rates and adult size.