Effect of Different Temperatures on Some Biological Aspects of the Predaceous Mite, Agistemus exsertus Gonzalez

Document Type : Original research articles

Author

Plant Protection Research Institute , Agri. Res. Center, Dokki, Giza, Egypt

Abstract

Life cycle of A. exsertus female differed according to temperature degree; the shortest period was at 30 °C, 8.23 days, while the longest at 20°C, 12.02 days. The developmental rate ranged from  68.14% at 20 °C to 73.04% at 30 °C for female. Survival female's  immatures %was also affected  with temperature being 73.45,  80.24 and 83.61% at 20, 25 and 30 °C, respectively. The total amount of consumed preys/predator different developmental stages and sex increased with increased temperature from 20 to 30 °C. The total average number of T. urticae fed by predator immatures was 17.23, 14.76 and 10.71  preys at 30. 25 and 20 °C.  Also, female  predator consumed greater number of prey individuals at high temperature,  78.34 preys at 30 °C,  decreased to 65.25  preys at 25 °C  but the rate of consumption was less at low temperature 50.00 preys at 20°C. The effect of temperature on life table parameters was determined. Net reproductive rate (Ro) differed according to temperature as this value  increased with temperature increase. Thus, these values averaged 11.21,  15.04  and 21.57  times  for  20,  25  and 30 oc.  The intrinsic rate of increase  (rm)  was 0.10,  0.13  and 0.15 individuals/female/day for the above same order. The mean generation time (T) decreased when the temperature increased.

Keywords

Main Subjects

Files

Share

How to cite

Statistics