Abstract:

The essential oils and its ethanol extract were prepared from Thymus mongolicus, and their contact toxicity against Tetranychus cinnabarinus were studied. The essential oil from T. mongolicus showed a strong contact toxicity with linear regress equation of Y=4.6691+1.4427 and LD50 of 3.95 mg/mL. Essential oil was extracted with hydrodistillation , and the contact toxicity of the essential oil against T. cinnabarinus was enhanced compared to ethanol extract with a relatively lower LD50 of 1.70 mg/mL. The contact LC50 value of essential oil and ethanol extract from T. mongolicus against T. cinnabarinus egg were 2.241 and 5.714 mg/mL, respectively. Key words: Thymus mongolicus; Tetranychus cinnabarinus; acaricidal activity