Effect of ultraviolet-C radiation on “Kumagai” guavas infested by Ceratitis capitata (Diptera—Tephritidae) and on physical parameters of postharvest

Abstract Physical quarantine methods are being developed to replace fumigants to control arthropods and microorganisms during post-harvest management of fruit and vegetables. This study aims to evaluate the use of UV-C radiation to disinfest guava with Ceratitis capitata (Wied.) eggs and evaluate the quality of fruit irradiated at two different storage temperatures. For the in vitro test, one-day old C . capitata eggs were exposed to increasing doses of UV-C radiation and stored in a B.O.D. chamber. Applying in vivo tests, ‘Kumagai’ guavas were exposed to artificial infestation by medfly. After infestation, the fruits were subjected to an increasing intensity of UV-C radiation and stored in a B.O.D. incubator at 23.0 ± 0.2 °C for about 20 days. In vitro tests indicated that 1.383 kJ m −2 UV-C on C. capitata eggs was capable of preventing the eclosion of larvae. However, guavas infested by medfly eggs needed 16.0 kJ m −2 of UV-C to prevent pupation. The guavas subjected to treatment with UV-C radiation and stored at a temperature of 8 ± 0.2 °C, obtained much better responses in terms of quality indices than those stored at 22 ± 0.2 °C, which lends credence to the storage temperature being a key factor in maintaining fruit quality.