Diflubenzuron-Induced Decrease of Egg Hatch of Screwworms (Diptera: Calliphoridae)1

Abstract

When diflubenzuron (N-[[(4-chlorophenyl) amino]-carbonyl]-2,6-difluorobenzamide) was fed to screwworms, Cochliomyia hominivorax , egg hatch was reduced. Males were not affected, but when females of 3 ages were fed the material. hatch was reduced. Moreover, inhibition was greater the more mature the eggs. The greatest inhibition occurred (often hatch was less than 5%) when females that comained mature eggs had fed at least 1 h and ingested at least O.4 mg of the chemical. Some eggs that hatched showed a delayed effect: the larvae died early in their development. Treated females gradually recovered from the effects of diflubenzuron during 10 days or so after treatment. The activity of the chemical was limited to a single gonotrophic cycle.