Ecological and Preliminary Control Studies of the Citrus Brown Mite Eutetranychus orientalis (Klein) (Tetranychidae: Acarina) on Two Citrus Varieties

Abstract

The population trend of the citrus brown mite Eutetranychus orientalis (Klein) was studied on two citrus varieties; Prior Lisbon Lemon and Washington Navel orange trees in the farm of the College of Agriculture. The symptoms of infestation on both leaves and fruits were discussed.

Mite population reached its peak during September and October. The highest amount of leaf drop occurred also in the fall as a result of infestation.

The application of wettable sulphur, and metasystox ‘i’, singly or in combination had lowered the number of the mite and the amount of leaf drop as compared to the check. However, both pesticides were responsible for the destruction of the natural enemies which allowed the phytophagous mite to increase freely. The wettable sulphur as a nutrient for citrus, had probably encouraged the phytophagous mite to increase. The lowest number of this tetranychid mite occurred when metasystox ‘i’ was applied alone. However, this organophosphorous compound had not effectively controlled the citrus brown mite.