1a. Objectives (from AD-416):
The goal of this project is to strategically tailor new phytosanitary treatments to be of benefit to the sweet cherry industry. The research objectives are to establish robust toxicological and phytotoxicological data sets for industry consideration.
1b. Approach (from AD-416):
Utilize a cooperative effort between USDA-ARS, other government action agencies, and industry to address fumigation challenges for the Washington State sweet cherry industry. The research team will scale promising technologies from laboratory-, through pilot-, and into commercial-size chamber fumigations with APHIS and specialty crop-specific industry input (i.e., confirm technical feasibility). Performance measures will build on each year’s progress and will relate to the identification of most effective and cost efficient postharvest processes for controlling pest insects.
3. Progress Report:
This Trust 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. Oriental fruit fly (OFF), Bactrocera dorsalis,is a key economic pest of the world. OFF is regulated as a quarantine pest in the US and many countries require US exports be completely free from infestation. Methyl bromide (MB) chamber fumigations were evaluated for postharvest control of OFF in fresh sweet cherry exports from Western USA, which are estimated at 300 million USD annually. Sweet cherries were infested with OFF, infested cherries containing the most MB-tolerant OFF life stage (2nd instar larvae) were buried amongst uninfested fruit in fruit bins consistent with commercial practice, and then the fruit bins were fumigated at 17.2 ºC. The effects of dose, duration, load type, and load factor on fumigation exposure were determined and results from efficacy trials indicate exposures of > ~250 (mg h/L) are required for greater than 99.9968% mortality. This research can be used by the US sweet cherry industry to address both domestic quarantines and trade barriers, should OFF outbreaks occur.