1a. Objectives (from AD-416):
Enhance production of California tree nuts via development of efficient, economical, and environmentally benign chemical strategies to reduce pest pressure in orchards.
1b. Approach (from AD-416):
We will assess the insecticide metabolites formed by fungus on the surface of nut hulls by conducting metabolic profiling using fungal cultures. We will also integrate laboratory metabolic profiling results (above) with collection and analysis of field samples to assess fungal-derived insecticide products and residual insecticide effectiveness under field conditions.
3. Progress Report:
This Assistance Type Cooperative Agreement was established to support Objective 1 of the in-house project and is related to finding postharvest methyl bromide alternatives and techniques for improving methyl bromide fumigations. Navel orangeworm (NOW) is a key insect pest of almonds that results in production and postharvest losses for industry. The goal of this project is to ensure strategic application of chemicals to control NOW in almonds by mapping the environmental fate and transport of insecticides, particularly degradative pathways involving fungal metabolism. University of Nevada collaborators conducted experiments related to the metabolic profiling of pyrethroids in fungus. In addition, the potential for fungal colonization over the course of a growing season has been enumerated and comparatively evaluated relative to other degradative processes, including abiotic factors (e.g., absolute humidity, sunlight, etc.) and chemical constituents of nut hulls (e.g., total phenolics, transient oxidant flux), which participate in indirect photochemcial degradation.