Methyl eugenol and cue-lure traps for suppression of male oriental fruit flies and melon flies (Diptera : Tephritidae) in Hawaii: Effects of lure mixtures and weathering

Methyl eugenol (4-allyl-1,2-dimethoxybenzene-carboxylate) and cue-lure [4-( p-acetoxyphenyl) -2-butanone] are highly attractive kairomone lures to orie ntal fruit ny, Bactrocera dorsalis (Hendel), and melon fly, B. cucurbitae ( Coquillett), respectively. Plastic bucket traps were evaluated as dispenser s for methyl eugenol and cue-lure for suppression of the 2 fruit flies in H awaii. Methyl eugenol and cue-lure mixtures were compared with pure methyl eugenol or cue-lure over 4 seasons. B, dorsalis captures differed significa ntly with treatment and season. B. dorsalis captures with 100% methyl-eugen ol were significantly greater than all other treatments (25, 50, and 75%). B. cucurbitae captures also differed significantly with treatment but not w ith season. Captures with 100, 75, and 50% cue-lure were not significantly different. Bucket traps baited with cue-lure (+ malathion) and weathered. u nder Hawaiian climatic conditions were attractive to B. cucurbitae up to 8 wk. Two methyl eugenol dispensers (canec disks and Min-U-Gel) were compared with bucket traps. Dispensers (methyl eugenol + malathion) were weathered for 2-16 wk under Hawaiian climatic conditions and bioassayed during summer and winter. Initially, captures of B. dorsalis were not significantly diff erent for the 3 dispensers. Bucket traps and canec disks were most resistan t to weather, remaining attractive to B. dorsalis flies up to 16 wk. Min-U- Gel was least resistant, losing attractiveness to B, dorsalis flies within 2 wk. On the basis of performance, bucket traps and canec disks were equall y long-lived up to 14 wk; thereafter, bucket traps were slightly more attra ctive during winter. Canec disks were cheapest, but on the basis of possibl e environmental concerns, bucket traps may be the best all-around choice fo r areawide suppression of fruit flies.