Effect of temperature on the development of Eotetranychus hirsti (Tetranychidae) on fig leaves

The fig spider mite, Eotetranychus hirsti is one of the major pests of fig trees worldwide. The effect of temperature on the developmental time and the survival rate of E. hirsti feeding on fig leaves was determined at six constant temperatures of 15, 20, 25, 30, 32 and 35 ?C. The total developmental time of females (from egg to adult emergence) at the above-mentioned temperatures was 41.29, 24.15, 16.95, 12.35, 10.21 and 10.67 days, respectively. The lower, optimal and upper developmental threshold (Tmin, Topt and Tmax, respectively) and thermal constant (K) of the pest were estimated by ordinary linear and Logan 6 nonlinear models. The lower temperature threshold (Tmin) and thermal constant (K) of the immature stages were estimated to be 9.86 ?C and 239.48 degree-days (DD), respectively. The Topt and Tmax were estimated to be 34.30 and 35.44 ?C, respectively. As the temperature increased from 15 to 30 ?C, the survival rate of immature stages increased from 33.33 to 70.59 %, then decreased and reached 54.91 % at 35 ?C. Temperature-dependent development data, thermal requirements and temperature thresholds can be used to predict the occurrence, number of generations and population dynamics of E. hirsti.