Abstract:

The different solvent extracts from different organs of Euphorbia fischeriana were tested for their acarocidal activities against Tetranychus cinnabarinus. The results indicated that petroleum ether extract of the root was more active than that from leaves and stems, and other solvent extracts from any organs, and it exhibited stronger activity against female adult. The adjusted mortality of female adult was 52.73% in 24 h at the concentration of the petroleum ether extract of 1 mg·mL^-1 but the adjusted mortality of egg was 55.21% when the concentration was 4 mg·mL^-1. The bioassay result of liquid-liquid extract showed that petroleum ether phase was obviously more active than chloroform phase and methanol phase. The silica gel column was used to separate and purify petroleum ether part and 16 bands were obtained by TLC analysis. The bioassay result indicated that the 11^th band had strongest acarocidal activity against T.cinnabarinus and the adjusted mortality of female mite was 86.67% at the concentration of 1 mg·mL^-1 and the adjusted mortality of egg was 66.33% at the concentration of 4 mg·mL^-1.

Key words: Euphorbia fischeriana, Tetranychus cinnabarinus, acarocidal activity