The alpha -amylase inhibitor acarbose does not affect the parasitoid Venturia canescens when incorporated into the diet of its host Ephestia kuehniella.

摘要

Amylase inhibitors (AIs) are suitable candidates for protecting plants and their products from attacks by herbivorous and granivorous insects. However, detailed studies of the suppressive effects of AIs on target and non-target insects are necessary before their application in post-harvest protection. To address this issue, laboratory bioassays were used to test the effect of the non-proteinaceous inhibitor acarbose on a stored product pest, the flour moth Ephestia kuehniella(Zeller) (Lepidoptera: Pyralidae), and its parasitoid Venturia canescens (Gravenhorst) (Hymenoptera: Ichneumonidae). Two sublethal concentrations (0.001 and 0.0001%, wt/wt) of acarbose were incorporated into the diet of parasitized and unparasitized larvae of E. kuehniella. Development time and fresh body weight of the larvae, together with the size of the wasps, were compared for insects reared on acarbose-treated and control diets. On the diet containing 0.001% acarbose, the developmental time was longer and relative weight gains of the E. kuehniella larvae were lower, but the weight of the larvae prior to pupation was similar to that of the control. The acarbose did not have a suppressive effect on the parasitoid V. canescens; in fact the wasps that emerged from the hosts reared on a diet containing 0.0001% acarbose were on average larger and heavier than the controls. These results demonstrate that it might be possible to enhance the control of stored product pests by using both biological control and AIs..