Effects of Thermal Treatments on Control of Sawtoothed Grain Beetle and Quantity and Quality Characteristics of Date Palm (Phoenix dactylifera cv. Zahedi)

One of the major issues in date production and packaging are storage pests such as Oryzaephilus surinamensis which cause reduction in date postharvest quality. Present experiment was carried out to study mortality impacts of exposure of O. surinomensis larvae, pupa and adults in laboratory to extreme temperatures (45, 50, 55, 60 °C) in a factorial in completely random design with three replications. Peel separation from pulp, TSS, fruit humidity, pH and perishability percentage were measured.  Data were analyzed using MSTAT-C software and means were compared using the Duncan test at 1% and 5% probability levels. The results showed 100% mortality after 3h of exposure to 55 °C in the development stage (larvae, pupa, adult). High temperature treatments reduced fruit weight compared with control.  Heat treatments influenced fruit moisture content. However, the responses were not significantly different in comparison with control until 50 °C. Effect of temperature treatments on TSS, pH and perishability percentage was not significant compared with control. 0 and 60°C treatments reduced the rate of peel separation from pulp.