Action modes of Aloe vera L. extracts against Tetranychus cinnabarinus Boisduval (Acarina: Tetranychidae)

Objective: This paper mainly determined the action modes of extract of Aloe vera L. against Tetranychus cinnabarinus Boisduval. Methods: The different action modes, contact action, repellent, fumigant, and oviposition inhibition property of the acetone extract of Aloe vera L. leaf against the carmine spider mite Tetranychus cinnabaribus (Boisduval) (Acarina: Tetranychidae) were investigated at 26°C ± 1°C, 75% - 80% relative humidity, and 14:10 light: day cycle in the laboratory. Results: Based on the established toxicity regression line of the Aloe vera L. acetone extract against female adult mites, the median lethal concentrations (LC50) were 0.836 and 0.167 mg/mL for 48 and 72 h, respectively. With processing time increased, the contact acaricidal activity increased and the repellent activity gradually decreased. The main modes of action of the extract against female adult mites were contact and repellent, and preferable effects were observed on adult mites. These results indicate that A. vera L. extract contains acaricidal and repellent bioactive components that may be useful in future control of the phytophagous mites.