Submitted to: European Meeting in the IOBC/WPRS Working Group
Publication Type: Abstract Only
Publication Acceptance Date: 9/10/2005
Publication Date: 10/26/2005
Citation: Yokoyama, V.Y., Miller, G.T. 2005. Olive fruit fly biology and cultural control practices in california. European Meeting in the IOBC/WPRS Working Group "Integrated Protection of Olive Crops" 26-28 October 2005, Florence, Italy. p. 75.
Technical Abstract: Olive fruit fly, Bactrocera oleae (Gmelin), first found in California, USA in 1998 was investigated in laboratory and field studies. Mortality of 1-5, 6-8, 9-11, and 12-14 d-old immature insects in olives was 19-75, 13-58, 5-27, and 0-7% when exposed to 15C and 60% relative humidity (RH), and was 14-31, 8-32, 16-38, 4-22% when exposed to 25C and 35% RH, respectively. Mortality decreased with an increase in age at all temperatures except for 9-11 d-old larvae exposed to 25C and 35% RH. Mortality was 100% in all immature stages in fruit exposed to 5C and 85% RH., and 35C and 25% RH. The pre-ovipositional period for adult females was 13.0 ± 4.0 d; peak oviposition occurred at 19.7 ± 1.8 d; and, egg laying ended after 63.7 ± 3.8 d (mean ± SEM) at 23C. Olive fruit fly was found to attack fruit <1.0 cm3. Adults trapped in baited yellow panel traps with male attractant were higher in olive trees with irrigation water at the base (39.9 ± 8.7 adults per trap per week) than in olive trees without irrigation water (27.7 ± 6.4 adults per trap per week) in the absence of fruit in the canopy. The highest numbers of adults were collected between 2 and 9 October. The daily mean temperature (15C) and relative humidity (74%) was similar in trees with and without water at the base. Percentage mortality of olive fruit fly 3rd instars was greater than young (0-4 d-old) and old (9-12 d-old) pupae after immersion in water and sand for 1-5 d, and young pupae were in general more susceptible than old pupae.