Dacus ciliatus (lesser pumpkin fly).

D. ciliatus is a major pest of a wide range of Cucurbitaceae in Africa, Asia and the Middle East. Adult flight and fruit transport are major means of dispersal. It may cause indirect economic impact on exports and could become a serious pest if introduced in the USA. It is an EPPO A1 quarantine pest within the category 'non-European Trypetidae' and is also of quarantine significance to CPPC (Caribbean Plant Protection Commission). Demographics, the main component of competition for fly species, have only been studied for this species by Vayssières et al. (2008). Compared to Bactrocera cucurbitae, it has longer egg incubation and immature stages, both disadvantages when competing for the same habitat. Preference for certain hosts allows D. ciliatus to enhance its biotic potential and maintain low population levels when competing with the melon fly, especially at low altitudes. D. ciliatus could colonize low temperature areas, as has been the case in Mediterranean areas. D. ciliatus seems less wiling to exploit new hosts compared to B. cucurbitae.

An Integrated Decision Support System for Environmentally-Friendly Management of the Ethiopian Fruit Fly in Greenhouse Crops

The Ethiopian fruit fly (EFF), Dacus ciliatus, is a key, invasive pest of melons in the Middle East. We developed and implemented a novel decision support system (DSS) to manage this pest in a greenhouse environment in Southern Israel. Dacus ciliatus is commonly controlled in Israel with repeated calendar-sprayings (every 15 days) of pyrethroid pesticides. The current study compares the performance of a DSS against calendar-spraying management (CSM). DSS was based on EFF population monitoring and infestation. DSS took into consideration concerns and observations of expert managers and farmers. During 2014, EFF damage was concentrated in the spring melon production season. Fall and winter production did not show important damage. Damage during the spring of 2014 started to increase when average EFF/trap/day reached 0.3. This value was suggested as the threshold to implement pesticide spraying in DSS greenhouses. EFF/trap/day trends were derived from monitoring with conventional traps and a novel electronic remote sensing trap, developed by our group. CSM during the spring of 2015 included 3 EFF control sprays, while DSS-managed greenhouses were only sprayed once. At the end of the spring season, damage was slightly higher in DSS greenhouses (1.5%), but not significantly different to that found in CSM greenhouses (0.5%). Results support continuing DSS research and optimization to reduce/remove pesticide use against EFF in melon greenhouses. Interactions with farmers and managers is suggested as essential to increase adoption of DSS in agriculture.

Laboratory longevity and competitiveness of Dacus ciliatus Loew (Diptera: Tephritidae) following sub-sterilizing gamma irradiation

The effect of a sub-sterilizing gamma radiation dose on Dacus ciliatus adults was investigated to assess the suitability of the sterile insect technique (SIT) as an alternative method to control this pest. Late pupae (48 h prior to adult emergence) from a laboratory strain were irradiated with 120 Gy of gamma rays emitted by a 60Co source. Following adult emergence, the mortality of irradiated and non-irradiated cohorts was recorded. Over a period of 50 days after emergence, no significant negative effects of irradiation upon the longevity of male or female laboratory flies were observed. A laboratory competitiveness study (Fried test), using irradiated laboratory and wild males at a ratio of 3:1 was conducted to assess the ability of irradiated males to reduce the egg hatch rates of a wild population. The overall competitiveness was found to be ca. 0.32, suggesting a reduced, but satisfactory, quality of irradiated laboratory as compared with wild males. Based on the above findings, we calculated and proposed effective male release ratios for field application of SIT against D. ciliatus.