A New Report on Acaricidal Activities of Wikstroemia chamedaphne Extracts against Tetranychus viennensis (Acari: Tetranychidae)

Few studies mentioned acaricidal activity of Wikstroemia chamedaphne against Tetranychus viennensis. Here, we reported that W. chamedaphne had strongly acaricidal activity against T. viennensis. A method for purification of miticidal components from W. chamedaphne was developed as follows: Step 1, methanol immersion at room temperature; Step 2, liquid-liquid partition using petroleum ether; Step 3, conventional column chromatography and thin layer chromatography. The efficiency of various extraction techniques was also compared using extraction rate and mortality rate as its index of evaluation. Two fractions, named WCME-7 and WCME-11, were got from W. chamedaphne. WCME-7 had a LC50 value of 0.14 mg/mL for female adults T. viennensis, and 0.09 mg/mL for WCME-11. Furthermore, the effects of various extracts of W. chamedaphne on female adults, eggs and nymphae in every stage of mites were further studied. Nymphae were most sensitive to W. chamedaphne extracts, female adults were in the second place, and eggs were the least. Briefly, W. chamedaphne is a potential source of botanic acaricide against T. viennensis.