The efficacy of an improved form of the mass-trapping method, for the control of the olive fruit fly, Bactrocera oleae (Gmelin) (Dipt., Tephritidae):: pilot-scale feasibility studies

The efficacy of an improved form of the mass-trapping method for the control of the olive fruit fly, Bactrocera oleae (Gmelin) was tested for 4 years in a pilot test at Tanagra Voeotia, Greece. Improvements consisted of the extension of the active life of the toxic trap used, active life referring both to its attracting and killing properties, as well as in trap deployment, which combined efficacy and low cost. The method was compared to bait sprays applied from the ground, which constitutes the current standard method for the control of this pest. Both pest population density and fruit infestation levels, the main parameters used for the evaluation of the two methods were considerably lower during all 4 years of tests in the orchards protected by mass trapping compared with those in the orchards protected by bait sprays. Furthermore no complementary measures were required in the mass-trapping orchards for acceptable crop protection, which was not the case under certain conditions, prior to the introduction of the recent improvements. The cost of the mass-trapping method was approximately US$ 0.40 per tree per year compared with US$ 0.35 for bait sprays (figures of the Greek Ministry of Agriculture). However, the mass-trapping method reduces the amount of insecticide used for olive protection by 99.5% (15 mg a.i. per tree per year as opposed to 3 g in the case of bait sprays). A considerable reduction in the cost of the mass-trapping method is expected with the extension of its use and the mass production of materials used, especially traps.