Irradiation disinfestation of wheat, dried wheat products and mushrooms

The aim of the study was to establish the radiosensitivity of Nemapogon granellus, Plodia interpunctella, Tribolium confusum, Sitophilus granarius and Sitophilus oryzae in wheat germ, wheat bran and wheat in order to determine the dose for disinfestation. Some important chemical parameters of the irradiated materials (vitamin E, lipids and dietary fibres) were investigated, including the radiation dose, packaging materials and storage conditions. The eggs and larvae of N. granellus and P. interpunctella were treated with 0.1, 0.2, 0.4 and 0.8 kGy in dried mushrooms. A dose of 0.2 kGy was enough to control N. granellus in the eggs and at the larval stage. This dose could be used to disinfest mushrooms infested with this moth. The egg hatch in P. interpunctella was prevented at 0.4 kGy and adults were sterilized at 0.1-0.2 kGy. No adults emerged when the larvae were irradiated at 0.8 kGy. However, for the disinfestation of dried mushrooms, a dose of 0.4 kGy is sufficient to control both species of moth. The radiation sensitivity of T. confusum was studied in doses ranging from 0.2-0.8 kGy. It was found that the eggs were more sensitive to radiation than the larvae and pupae. However, a 0.2 kGy dose of irradiation killed these forms, or their further development was inhibited. Adults died after 10 days of irradiation at 0.8 kGy. For disinfestation, a dose of 0.4 kGy is advocated. 7 refs, 8 tabs