Some Biological Aspects of the Two-Spotted Spider Mite, Tetranychus urticae Koch, (Acari: Tetranychidae) at Constant Temperatures

Document Type : Original Article

Author

Plant Protection Research Institute, Agricultural Research Center

Abstract

Biology of the two spotted spider mite, Tetranychus urticae Koch was studied at constant temperatures of 26º and 30ºC. A temperature of 30º was found to be the most favorable temperatures for the development and multiplication of this pest. Threshold temperatures (t0) of 12.87º, 12.92º, 9.45º, and 13.94 ºC were calculated for the egg, larvae, protonymph and deutonymphal stages, respectively. Based on these thresholds the stages respectively needed about 63.35, 26.81, 30.95, and 26.17 day-degrees to complete their development. Thermal units required to develop one generation of this pest was about 146.48 day-degrees using 12.50ºC as a base temperature.

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