Assessing the efficacy of controlled atmosphere temperature treatment system (CATTS) against codling moth inside harvested apples

The controlled atmosphere temperature treatment system (CATTS) was assessed as a disinfestation tool to control codling moth (CM; Cydia pomonella) larvae inside apples. Codling moth mortality and apple quality were assessed after exposure to one of 10 treatments, which were combinations of five variables, namely, O2 concentration (air 20.9%, 1, 2 or 3%); CO2 concentrations (air 0.04% or 15%); 12 or 24˚C/h ramp rate up to 46˚C; air speed 1.3 m/s; and either 2.5- or 3-h treatment time. CATTS treatments resulted in higher CM mortality than equivalent hot air treatments. The treatments involving 1 or 2% O2 combined with 15% CO2 and a ramp of 12˚C/h or 24˚C/h to 46˚C, with a total treatment time of 3 h or 2.5 h and a 1.3 m/s air speed resulted in 100% mortality of CM. However, all CATTS and hot air treatments compromised apple quality. High CM mortality can be achieved using CATTS, but refinement of the protocol is needed to improve fruit quality outcomes.