Location: Commodity Protection and Quality Research
Project Number: 2034-43000-043-078-T
Project Type: Trust Fund Cooperative Agreement
Start Date: Mar 1, 2025
End Date: Feb 28, 2026
Objective:
1) Improve procedures for X-ray irradiation of Navel Orangeworm pupae to obtain sterile adults.(Objective 1B in the proposal)
2) Obtain field data on recapture of locally-produced Navel Orangeworm. (Objective 3 in the proposal)
Approach:
1) Navel Orangeworm moths will be internally marked by rearing them on a diet containing a fat-soluble red dye. Silked cocoons from these cultures will be collected using hand-separation or improved techniques. Pupae aged such that they contain unemerged adults will be exposed to 0, 150, 200, 250, 300, and 350 Gy using an x-ray irradiator. Adults emerged from these pupae will be mated with unirradiated adults and allowed to oviposit onto a filter paper. This filter paper will be placed on laboratory diet in a Petri dish, and fertility will be compared between doses by counting progeny at the end of the larval stage. Following confirmation of dosimetry, mixed-sex pupae processed a described will be held at 10°C to delay until they are placed in the field.
2) X-ray irradiated pupae will be produced and transported as described above. NOW will be released in the center of a roughly square orchard or orchard section, and a grids of pheromone traps (for males) and oviposition bait traps (for females) will be used to examine variation in percent of moths recaptured and dispersal patterns.
