PARASITIZATION OF IRRADIATED EGGS AND EGGS FROM IRRADIATED ADULTS OF THE INDIANMEAL MOTH (LEPIDOPTERA, PYRALIDAE) BY TRICHOGRAMMA-PRETIOSUM (HYMENOPTERA, TRICHOGRAMMATIDAE)

Eggs of P. interpunctella (Huebner), either irradiated with 35, 50 or 100 krad or obtained from irradiated adults (5, 10, 15 or 50 krad), were exposed to adults of the egg parasite, T. pretiosum Riley. In paired host preference tests, eggs irradiated with 35 krad were not preferred to control eggs, but those irradiated with 50 or 100 krad were preferred to control eggs, but those irradiated with 50 or 100 krad were preferred. Eggs from adults irradiated with 5, 10 or 15 krad were parasitized at the same rate as control eggs, but eggs from 50-krad irradiated adults were significantly less preferred. Eggs irradiated with 50 krad were preferred to eggs from adults irradiated with 50 krad. The data indicate that Indianmeal moth eggs killed by irradiation could be used for the rearing and release of T. pretiosum into commodity storages, or alternatively the use of T. pretiosum could be combined with the release of substerilized adult moths as part of an integrated control approach for Indianmeal moth population suppression in commodity storages.