A thermal lethal model of rice weevils subjected to microwave irradiation

An industrial continuous microwave oven was employed to investigate pest control in rice to develop a new, innocuous and safe method to replace chemical fumigation. Microwave irradiation conditions affecting rice temperature and pest mortality were studied. Adults and eggs of rice weevils (Sitophilus oryzae L.) suffered 100% mortality when final rice temperature was above 55 °C, while the corresponding energy consumption of the microwave was above 0.017 kW h/kg. Lower power with a longer treatment time is more effective at killing insect pests using the same total energy consumption. A mortality model for rice weevils based on final rice temperature was formulated. Eggs were more susceptible to temperature than adults.