The efficacy of different attractant trap combinations for monitoring of Afrotropical fruit flies was evaluated in commercial fruit production areas and natural areas in the northern parts of South Africa. Five food‐based attractants: three‐component Biolure, a combination of ammonium acetate and trimethylamine, a combination of ammonium acetate and putrescine, torula yeast and Questlure, were evaluated in McPhail‐type traps. Two male lures targeting Ceratitis species: EGO Pherolure and trimedlure, were evaluated in Sensus bucket traps. Three male lures targeting Dacine fruit flies: methyl eugenol, cue lure and zingerone, were evaluated in Moroccan bucket traps. The three‐component Biolure was among the most effective food‐based attractant for females of Ceratitis capitata, C. rosa (R1 and R2), C. cosyra and Bactrocera dorsalis. EGO Pherolure attracted a wider range of Ceratitis species than trimedlure but was equally as effective as trimedlure for males of C. capitata and C. rosa (R1 and R2). Dacine flies were specific in their responses to male lures. Bactrocera dorsalis males responded mainly to methyl eugenol. Males of Dacus species responded to either cue lure or zingerone. Zingerone attracted two cucurbit‐infesting Dacus species: D. frontalis and D. durbanensis. For B. dorsalis, C. capitata and C. cosyra in commercial fruit production areas, patterns of female catches in traps containing food‐based attractants were different to patterns of male catches in male lure‐based traps. Implications of these trapping results are discussed.

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Markets importing citrus fruit including lemons, Citrus limon (L.) Burman f., from South Africa require that the fruit be free of fruit fly pests (Diptera: Tephritidae). Historically there has been no fruit fly infestation recorded on lemons destined for export from South Africa. In this study, we assessed the host status of commercial export grade Eureka lemons, Citrus limon (L.) Burman f. cv. Eureka, for four fruit fly pest species of economic importance in South Africa: Ceratitis capitata (Wiedemann), Ceratitis rosa Karsch, Ceratitis quilicii De Meyer, Mwatawala & Virgilio, and Bactrocera dorsalis (Hendel). Trapping was conducted in 10 Eureka lemon orchards in two major citrus production regions over two citrus seasons between 2016 and 2017 to determine the level of fruit fly abundance in the sampled orchards. Lemons were collected at harvest over the two seasons in the same orchards where trapping was conducted. Fruit fly infestation of the sampled lemons was determined by dissection. Additionally, infestation of lemons was determined under forced exposure to mature mated females of C. capitata and B. dorsalis. Trapping data showed the presence of adults of all four fruit fly species in the sampled lemon orchards. No fruit fly infestation was detected in 43 222 Eureka lemons sampled at harvest. There was also no infestation of lemons under forced exposure conditions. The results of this study provide evidence with 99.99 % efficacy and a 99 % confidence level that South African commercial export grade Eureka lemon fruit is not a host for C. capitata, C. rosa, C. quilicii or B. dorsalis.

BACKGROUND Attractant‐based trapping is used in the establishment of pest‐free areas and areas of low pest prevalence for fruit flies (Diptera: Tephritidae). Male lures are commonly used attractants in fruit fly trapping. In this study, the effects of male lure dispensers, traps and combinations of dispensers and traps on monitoring of two fruit fly pests, Ceratitis capitata (Wiedemann) and Bactrocera dorsalis (Hendel), were investigated in South Africa. RESULTS In the male‐lure‐based trapping systems evaluated, trimedlure (TML) for C. capitata and methyl eugenol (ME) for B. dorsalis, the type of dispenser affected catches for both species. Higher catches of B. dorsalis males were recorded in bucket traps baited with a dispenser containing 15 g ME compared with traps baited with dispensers containing either 4 g ME or 2 g ME. Catches of C. capitata males were higher with dispensers containing TML than those with TML plus extender (Capilure®). The type of trap used with TML also influenced catches of C. capitata with higher numbers recorded in yellow Delta trap compared with the Sensus bucket trap. CONCLUSIONS Dispensers with higher ME loadings are more effective for monitoring of B. dorsalis. The yellow Delta trap baited with TML (without extender) would be an effective monitoring system for C. capitata. Fruit fly prevalence levels as determined by specific trapping systems should be related to their efficiency in terms of catches of the target pests. © 2020 Society of Chemical Industry