Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/2/1999
Publication Date: N/A
Interpretive Summary: New export markets for California table grapes have been limited by pests such as omnivorous leafroller that have the potential to be accidently introduced through shipments into foreign countries where the insect is not found. Low temperature storage combined with sulfur dioxide slow release pads were investigated as a quarantine treatment to control the pest. A three week exposure period was found to cause 100% mortality of omnivorous leafroller larvae in packed table grapes. The combination treatment incorporates existing packinghouse facilities and has potential to be used as an alternative to chemical fumigants such as methyl bromide to control this pest when of regulatory concern.
Technical Abstract: Low temperature storage combined with sulfur dioxide slow release pads caused 100% mortality of omnivorous leafroller, Platynota stultana Walshingham, 2nd instar larvae (the least susceptible stage to low temperature storage) after 3 wks of exposure in table grapes, Vitis vinifera L. Temperatures in packed grape clusters decreased from ambient to 2C within approximately 2 d after placement in storage. Sulfur dioxide concentrations in the grape clusters ranged between 0.2 and 1.0 ppm during the 1-6 wk storage period. The combination treatment uses existing packinghouse facilities and has potential to control the pest in table grapes for export.