POSTHARVEST QUARANTINE DISINFESTATION OF ZUCCHINIS AND ROCKMELONS AGAINST BACTROCERA-CUCUMIS (FRENCH) USING INSECTICIDE DIPS OF FENTHION OR DIMETHOATE

The disinfestation efficacy of a 1-min dip in fenthion or dimethoate (400 mg/L in water) was tested against eggs and larvae of the cucumber fly, Bactrocera cucumis, in zucchinis and rockmelons. Each trial involved >30 000 individuals. Fenthion gave 100% mortality of eggs and third instar instar larvae in rockmelons, 100% mortality of eggs in zucchinis, and >99.99% mortality of third instar larvae in zucchinis. Dimethoate gave 100% mortality of eggs in zucchinis, >99.98% mortality of third instar larvae in zucchinis, and >99.99% mortality of eggs and larvae in rockmelons. Residues of fenthion and dimethoate in zucchinis or rockmelons were below the Australian maximum residue limit of 2 mg/kg on the day of treatment. There were no adverse effects on taste.