Efficacy of gamma-irradiation and ozone to protect some stored products from insects

Abstract EN

Adults of Sitophilus zeamais (L.), Tribolium castaneum (Herbst), Rhyzopertha dominica(F.), Oryzaephilus surinamensis(L.), Plodia interpunctella(Hubner) , Ephestia cautella and, Sitotroga cerealella (Oliv.); the third instar larvae of external feeder species tested beside Corcyra cephalonica were exposed to gamma irradiation and ozone in different nutrition materials (date, wheat, flour and maize) .

The effect of a gamma- irradiation dose 750 Gy on the adults R.

dominica and S.

cerealella were negligible or slow during the first and second day post treatments.

By increasing the dose to 1500 Gy, the percent mortality of both adults were 41.43& 50.0, respectively, after three days from treatment.

On the other hand all adults tested died within 5 days when exposed to dose 3000 Gy except T.

castaneum.

Experiments were performed to determine the effect of ozone in different exposure times (25, 50, 75, 100 and 150 min.) to control these insect pests.

The adults of S.

zeamais, S.

cerealella and P.

interpunctella, were more susceptible to ozone than other tested adults; complete mortality is obtained with exposure time 75 min after one day of treatment.

The most resistant adults in this study were T.

castaneum.

Mortality of four tested larvae was increased with increasing exposure time to ozone; the larvae of C.

cephalonica consider the most tolerant to ozone fumigant.