The unsaponifiable matter and fatty acid methyl esters of the petroleum ether extract of seven plants with known acaricidal activity were fractionated and identified by GC chromatography, and their biological activity against the two-spotted spider mite, Tetranychus urticae Koch. (Acariforms: Tetranychidae) assayed. In general, unsaponifiable matter showed higher acaricidal activity than the saponifiable matter. The unsaponifiable matter of Dodonaea viscosa leaves was the most toxic and that of Callistemon lanceolatus leaves the least toxic. The saponifiable matter (fatty acids) of Curcuma longa was the most potent.
