Histopathology of Irradiated Yellow Mealworm Adult and Larval Midguts1, 2

Radiation dosages of 5-100 kilorads had a pronounced effect on the midgut of both larval and adult yellow mealworms, Tenebrio molitor L. (Coleoptera: Tenebrionidae). Degenerative changes were positively correlated with both dose and time elapsed after exposure. The regenerative cells that renew the epithelial lining of the midgut were particularly sensitive to radiation damage; the damage eventually resulted in loss of the midgut epithelium.