Cold treatment of table grapes infested with Mediterranean fruit fly Ceratitis capitata (Wiedemann) and Queensland fruit fly Bactrocera tryoni (Froggatt) Diptera: Tephritidae

Abstract

A series of trials, using standard bioassay procedures followed by large-scale export tests, were conducted on five table grape cultivars at 1°C, 2°C and 3°C against the Mediterranean fruit fly (MFF) and the Queensland fruit fly (QFF). MFF was found to be more tolerant to cold treatment than QFF as shown in tests required to achieve complete mortality in >100,000 insects. MFF control was achieved in 16 days at 1°C, 18 days at 2°C and 20 days at 3°C. QFF control was obtained in 12 days at 1°C and 14 days at both 2°C and 3°C. These results provide flexibility for static and in-transit quarantine treatments for export and are an effective alternative to methyl bromide fumigation.