Heat disinfestation of capsicums for export to New Zealand and interstate
This project details the investigation undertaken into the use of non-chemical postharvest heat treatment against fruit fly, with the current postharvest disinfestation treatment against fruit flies uses the insecticide dimethoate currently under review. Initial trials conducted used a vapour heat treatment although predicted doses that would be efficacious against fruit fly caused unacceptable levels of fruit damage. In an attempt to improve the efficacy of the treatment and maintain fruit quality, a combination treatment using vapour heat treatment and cold treatment was investigated. The combined treatment did not achieve the required insect mortality and also resulted in unacceptable fruit damage. A third treatment option using vapour heat treatment with low oxygen was examined. Again, predicted doses that would be efficacious against fruit fly caused unacceptable levels of fruit damage. An alternative to heat treatments may be the use of irradiation. Small scale preliminary trials indicate that capsicums (green and red) will tolerate treatments as high as 600 Gy (150 Gy is required for control of fruit fly).