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Accueil du site → Projets de développement → Projets de recherche pour le Développement → 2007 → ENHANCED MANAGEMENT OF OLIVE FRUIT FLY IN CALIFORNIA USING ALTERNATIVE TACTICS

United States Department of Agriculture (USDA) 2007


Olive Fruit Fly

United States Department of Agriculture (USDA) Research, Education & Economics Information System (REEIS)


Identification : CA-R*-ENT-7689-SG

Pays : Etats Unis

Durée : Jul 1, 2007 à Jun 30, 2009

Mots clés : olive olive fruit fly bactrocera oleae tephritidae diptera biological control ecology temperature impact ipm black scale non-target impacts gis gf-120 spinosad psyttalia lounsburyi braconidae


1) Colonize and field evaluate specific parasitoids [e.g., Psyttalia lounsburyi (Hymenoptera : Braconidae)] for biological control of olive fruit fly (OLF) ; 2) Evaluate the impact of GF-120 treatments on the survival and viability of introduced parasitoids ; 3) Verify whether high summer temperatures sufficiently impact OLF survival to permit the elimination of some GF-120 sprays during the summer months ; and 4) Educate and demonstrate to olive growers the benefits of using these new tactics.

Obj. 1. Before general field release, selected parasitoid species will be tested in field cages to determine their ability to effectively impact olive fruit fly (OLF) populations under semi-natural conditions. OLF adults will be caged on branches that have susceptible stage olives. After the inoculated OLF reach a development stage that is susceptible to each selected parasitoid species, adult parasitoids will be released into cages. Successful parasitism will be determined, as well as parasitism rates and parasitoid development times. After field cage trials indicate promising candidate species for the various release locations (i.e., interior vs. coastal areas), we will begin general field-releases in California, with cooperation from California Department of Food and Agriculture (CDFA) personnel. Follow-up fruit samples and analyses of population dynamics of flies and parasitoids at release and non-release sites will be conducted to determine field impact, using standard sampling methodologies. Obj. 2. The acute impact of GF-120 on the natural enemies (Psyttalia lounsburyi and P. ponerophaga) of OLF will be quantified by determining parasitoid response (i.e., mortality) to varying concentrations of the product. Colonies of these natural enemies will be established. Three to five-day old adult females and males of each species will be exposed to various concentrations ( 5 levels of dilution) of GF-120 for three hours and then held for observation for up to 72 hours. A control treatment will also be included. Percentage mortality will be recorded at 12, 24, 48 and 72 hours. Individual experimental treatments will be applied to 10 individuals each and replicated 8 times each for each species / sex combination. Data will be analyzed using probit analysis. We will also look at the impact of weathered GF-120 residues on parasitoid survival by exposing natural enemies to 1, 2, 3, 5, 7, and 10-day old weathered droplets. Obj. 3. Using a flight mill to measure OLF flight distances, we will quantify the impacts of heat stress on the ability of OLF adults to fly. Young OLF adults (10-15 days old) will be exposed to one, two, or three days of diurnal temperature regimes within programmable temperature cabinets. On each day of exposure to a given temperature regime, flies will be given access to a) water and honey-water ; b) water only ; c) honey-water only ; or d) neither water or honey-water. Following a given exposure period (1 to 3 days at a given temperature regime) and water/food treatment, individual OLF adults will be attached to the flight mill and allowed to fly until the insect stops for more than one minute. We will be able to determine the distance flown, flight duration, and flight speed. Data (flight distances, duration, and speed) will be analyzed with three-way ANOVA. Obj. 4. Results from Objectives 1 - 3 will be presented and discussed at grower and consultant oriented-workshops and field days. We will also establish websites that provide information on the management tactics we develop. Information resulting from this project will be published in peer-reviewed scientific journals as well as grower assessable literature.

Présentation : USDA

Page publiée le 13 décembre 2015, mise à jour le 4 novembre 2017