Effects of sugar-formulated triflumuron-treated targets on reproduction in the olive fruit fly Bactrocera oleae (Diptera: Tephritidae)

Abstract

AbstractAdult olive fruit flies Bactrocera (Dacus) oleae Gmelin were exposed for 24 h to 25 × 10 cm polyester target devices, impregnated with 3% a.i. triflumuron (2-chloro-n-[[[trifluromethoxy]phenyl]amino]carbonyl]benzamide), a chitin synthesis inhibitor, formulated in 10% w/v sugar solution and air-dried. Treated insects were tested for egg hatch inhibition and larval mortality. Inhibition of egg hatch and F1 larval mortality depended on the sex exposed and the elapsed time after exposure. Egg hatch was reduced to 37.6% and F1 larval mortality reached 100% when both exposed sexes were mated. Exposure of one sex prior to mating resulted in a lower level of egg inhibition and larval mortality; but exposure of females was more effective at inhibiting egg hatch and larval survival than exposure of males in these crosses. In flies exposed once, the residual activity of triflumuron decreased gradually, fifteen days post-exposure egg hatch and larval mortality reached 62% and 44% respectively. Target devices aged under natural conditions reduced egg hatch to an average of 39% and inhibited completely larval development for a period of four months.