Ecological, biological and control studies on apple rust miteAculusschlechtendali (Nalepa) (Acari: Eriophyidae) in Egypt

The results showed that the population fluctuation continued at a moderate level until the mid of May and then started to increase until it reached to three peaks from the mid of June to the mid of Augustwhen the temperature degrees were at 29 -27.5 °C.A. schlechtendalioccur on the underside of the leaves and their feeding produces a patchy felt-like malformation on leaf surface and yellowing of hairs. The upper surface of foliage appears speckled, dull and faded.The population of the apple rust mite A. schlechtendali was significantly highest at the interval from the end of May to the mid of August. The obtaineddata indicated thatthe total developmental time of the immature stages was 6.95 ± 0. 42 and 7.18 ± 0.32 days for male and female, respectively, and the female fecundity was 54.80eggs; 3.07eggs/♀/day. Intrinsic rate of increase (rm) was found to be 0.208 individuals per female per day and the population multiplied 24.18 times in a generation time of 16.11 days under the given conditions.
The results of control pest experiments indicated that the Abamectin was superior in reducing the apple rustmiteA.schlechtendali(96%reduction) compared to Chlorfenapyr and Sulphur which had approximately equal reductions (88and 84% reductions, respectively).
The study ended with the conclusion that. The apple rust miteA.schlechtendaliis considered to be disastrous as its intrinsic rate of increase (rm) is high and the best control of this species at this interval was attained with Abamectin.