Comparison of Insecticide Toxicity in Adults of the Fruit Flies Anastrepha fraterculus (Wied.) and Anastrepha grandis (Macquart) (Tephritidae)

Abstract

Fruit flies (Diptera: Tephritidae) of economic and quarantine significance are responsible for both quantitative and qualitative losses in horticulture. Most producers in Brazil use insecticides as a cover spray for the control of fruit flies. Here new insecticide molecules were evaluated under laboratory conditions as potential replacements for organophosphates to provide protection and prevent damage to horticultural crops. Five pairs of Anastrepha fraterculus (Wied.) and Anastrepha grandis (Wied.) were placed into Petri dishes and exposed to eight insecticides using a Potter spray tower. The number of insect deaths was monitored until 21 hours after spraying. In general, both Anastrepha species exhibited similar susceptibility to the insecticides. Different fruit fly mortalities were observed among the insecticide treatments beginning 30 minutes after exposure. Interactions were verified between the compounds and fruit fly species and between evaluation periods and treatments. Acetamiprid, deltamethrin, flypyradifurone (1.60 ppm), imidacloprid, phosmet, thiamethoxam and zeta-cypermethrin caused similar mortalities 21 hours after treatment for both fruits fly species.