Possible application of EB machines for plant quarantine treatment

For plant quarantine treatment, irradiation is an effective alternative met hod to methyl bromide fumigation. In Japan EB and X-rays are used for this purpose. To obtain the optimum irradiation conditions for cut flowers or fr esh fruits, it is necessary to irradiate the package with a dose uniformity ratio below 1.4 or 2.0, respectively. In this study, computer tomography ( CT) was applied to measure the density distribution in the package for the purpose of estimating-dose uniformity. For large-scale irradiation by X-ray s, a simulation study was also carried out using the DEX code. These result s show two sided irradiation is suitable for the treatment of cut flowers a nd fruits. CT combined with the irradiation planning system DEX is useful f or the estimation of dose uniformity in packages for quarantine treatment. (C) 2000 Elsevier Science Ltd. All rights reserved.