Advances in insect pest management in postharvest storage of cereals: novel techniques

Description

Irradiation is a viable alternative to fumigation as a pre- or post-shipment quarantine treatment for control of stored product insects and pathogens in cereals and grains. Electron beam (e-beam) and x-ray are machine sources of ionizing radiation that avoid the problems associated with the transportation of radioactive isotopes. Electron beam has low penetration but high efficiency. X-ray has excellent penetration properties but is less energy-efficient than electron beam. E-beam is ideal for high throughput treatment, whereas x-ray systems are ideal for bulk or pallet-scale treatment of cereals and grains. Experiments were conducted using low energy electron beam (LEEB) and x-rays to disinfest rice. LEEB treatment of rice infested with Rhyzopertha dominica and Sitophilus oryzae at industrial throughput (1 tonne per hour) caused 100% mortality after 45 days. X-ray irradiation of infested bulk rice at a dose of 120 Gy sterilized Sitophilus oryzae and prevented further grain loss from weevil feeding. Irradiation may be helpful in controlling fumigant resistant insect populations (e.g. to phosphine) and could help manage resistance by preventing the spread of resistant insects in exported cereals and grains.

Table of contents

1 Introduction 2 Irradiation for control of stored product pests 3 Sources of ionizing radiation 4 Case study 1: low-energy electron beam treatment 5 Case study 2: high-energy X-ray treatment 6 Conclusion 7 Future trends 8 Where to look for further information 9 References