Laboratory studies were conducted to evaluate the effect of three temperature degrees (20, 25 and 3 0°C) on the
biology and life table parameters of the predator Typhlodromips (Amblyseius) swirskii, and its efficiency as biological
control agent for Tyrophagus putrescentiae and Aleuroglyphus ovatus on the dried oyster mushroom. The development
period of T. swirskii was shorter on T. putrescentiae than on A. ovatus recording 10.14, 7.90 and 5.20 days on T.
putrescentiae, and 13.33, 10.31 and 7.71 days on A. ovatus at 20, 25 and 30°C, respectively. The maximum female
longevity of T. swirskii was achieved at 20°C on T. putrescentiae and A. ovatus , recording 30.43 and 21.32 days,
respectively. The female longevity was decreased with the increase of the temperature to reach 17.11 and 11.34 days at
30°C. The population doubling time (PDT) and generation time (T) were inversely affected with increasing
temperature. In contrast, the intrinsic rate of increase (rm) and fmite rate of increase () were improved due to the
increase of temperature degrees. The net reproductive rate (RO) of T. swirskii was 10.60, 13.89 and 9.7 ion T.
putrescentiae , while it was 8.47, 12.00 and 7.12 on A. ovatus at 20, 25 and 30°C, respectively. The increases of rm for
T. swirskii ranged from 0.079 to 0.190 on T. putrescentiae and from 0.06 1 to 0.135 on A. ovatus. The results concluded
that the predation effect of T. swirskii on T. putrescentiae was greater than on A. ovatus. The greatest reductions (%) of
T. putrescentiae and A. ovatus by T. swirskii were noticed at 25°C with predator-prey ratio of 1:10, recording 73.90 %
and 65.2 1%, respectively.
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