Developmental biology of Amblyseius californicus (McGregor) (Acarina: Phytoseiidae), a predator of tetranychid mites, at three temperatures
The development time, survival and fecundity of Amblyseius californicus (McGregor), a predatory mite in deciduous fruit orchards, were determined at 20, 25 and 30°C. Using these values the intrinsic rate of increase (r(m)), mean generation time (T) and net replacement rate (R0) were estimated at the respective temperatures. In addition, the data were used to estimate the minimum temperature required for development. The r(m) increased with increasing temperature from 0.122 at 20°C to 0.251 at 30°C. The R0 was highest at 25°C (11.18 females/female) and was lower at 20°C (9.71 females/female) than at 30°C (10.54 females/female), while T decreased with increasing temperature from 20.11 days at 20°C to 10.20 days at 30°C. The estimated minimum temperature for development was 8.3°C, which indicates that A. californicus could survive the winter on plants in the covercrop in orchards and should be able to control populations of the phytophagous mite, Tetranychus urticae Koch, at temperatures below 30°C.