Effect of Controlled Atmosphere Storage on Adults and Immature Stages of Rhizopertha dominica (Fab.)

Abstract

Effect of controlled atmosphere parameters like carbon dioxide, oxygen concentration and period of storage were studied with 40, 50 and 60% concentrations of carbon dioxide; 16, 12, 8, and 4% oxygen, and the remaining as nitrogen. A setup was developed for production of gas mixtures for controlled atmosphere storage studies. The gases were metered separately, and mixed together in a gas mixing chamber generating the desired gas composition. The containers were purged with gas mixture after introducing counted number of adults or immature stages Rhizopertha dominica (Fab.), and were kept at 30oC in a temperature controlled chamber. Complete mortality of adults of was obtained in 5 days with 40% carbon dioxide at 16% oxygen level. With the reduced oxygen level of 8%, cent percent mortality of adults was achieved in 3 days. Complete mortality of eggs and early instar larvae were obtained with 40% carbon dioxide concentration in 9 days. Late instar larvae and pupae required 50% carbon dioxide concentration with 9 and 12 day treatment, respectively, for complete control. The control of all the life stages of R.dominica required a treatment with 50% carbon dioxide concentration for 12 days.