Hot-Air Treatment Device for Quarantine Research

Abstract

We describe a hot-air treatment device to be used in quarantine research to disinfest fruits of pests. The device consists of instruments mounted to a 1.905 cm thick plywood structure (1.2 m long by 1.2 m wide by 2.44 m high) with an insulated door. Relays, fuses, heater, fan, steam generator, airflow meter, dew-point sampling system, and thermocouple wires are connected to electricity and to each other through a main power panel and to a computer. The software used controlled air at precise dry-bulb and dew-point temperatures for selected time durations to prevent condensation on fruit surfaces and fruit desiccation. Air mass flow rate was adjustable with a variable speed control. When ‘Keitt’ mangoes infested with Caribbean fruit fly, Anastrepha suspense (Loew), larvae were treated with air at 51.67°C for 15, 30, 45, 60, 75, and 90 min, mortality was 20, 45, 79, 96, 100, and 100%, respectively. The estimated treatment time for 99.9968% mortality was 101 min (85-131 min, 95% FL).