Radiation-Induced Pathology in the Metamorphosis of the Mexican Fruit Fly (Diptera: Tephritidae)²

Late third instars of the Mexican fruit fly, Anastrepha ludens (Loew), exposed to ≥20 Gy of gamma radiation are able to pupariate normally but do not emerge as adults. Contrary to expectations, the imaginal discs were undamaged and metamorphosis to the pupal stage proceeded normally. Rather, development was arrested at the transition from cryptocephalic to phanerocephalic pupa, a process which requires vigorous muscular contractions. Protein metabolism during metamorphosis was found to be retarded in irradiated but living individuals relative to non-irradiated controls. These results suggest that a general radiation sickness is the cause of developmental arrest and eventual death of the pharate insect rather than a specific tissue atrophy.