Acaricidal Activities of Extracts of Kochia scoparia against Tetranychus urticae, Tetranychus cinnabarinus, and Tetranychus viennensis (Acari: Tetranychidae)

• Published in: Journal of economic entomology 2006-06, Vol.99 (3), p.858-863
• Main Authors: Shi, G. L., Zhao, L. L., Liu, S. Q., Cao, H., Clarke, S. R., Sun, J. H.
• Format: Article
• Language: English
• Subjects: acaricidal activity; acaricidal properties; Animals; Arachnida; Bassia scoparia; Bassia scoparia - chemistry; Biological and medical sciences; botanical pesticides; Control; Female; fractionation; Fundamental and applied biological sciences. Psychology; Generalities; HORTICULTURAL ENTOMOLOGY; Invertebrates; Kochia scoparia; lethal dose 50; mite control; mortality; Pesticides; Phytopathology. Animal pests. Plant and forest protection; plant extracts; Plant Extracts - chemistry; Protozoa. Invertebrates; Solvents; Tetranychidae; Tetranychus cinnabarinus; Tetranychus urticae; Tetranychus viennensis; toxicity
• ISSN: 0022-0493; 1938-291X; 0022-0493
• DOI: 10.1603/0022-0493-99.3.858

Extracts of an annual herbaceous plant, Kochia scoparia (L.) Schrad (Macrophomina), were bioassayed to determine their acaricidal activities against Tetranychus urticae Koch, Tetranychus cinnabarinus (Boisduval), and Tetranychus viennensis Zacher (Acari: Tetranychidae) in the laboratory. Extracts had both contact and systemic toxicity to these mites. Three solvents were tested for preparing crude extracts: petroleum ether, chloroform, and methanol. Methanol was the most effective solvent, extracting 3.11–4.53% of the acaricide. Petroleum ether was the least effective solvent, extracting 1.25–1.54%. However, extracts with chloroform resulted in the highest mite mortality (78.86%), and ultrasound-assisted extraction required the least time (10 min). Concentrated extracts were prepared using chloroform, methyl acetate, or distilled water as a solvent. Mite mortalities from the concentrated extracts by methyl acetate or distilled water were significantly lower than those by chloroform. The mean lethal concentrations (LC50) of the extracts by chloroform, methyl acetate, and distilled water to the mites were 0.71 ± 0.06, 2.08 ± 0.16 and 8.75 ± 0.062 mg/ml, respectively. After liquid chromatography and thin layer chromatography, the concentrated extracts by chloroform were separated into seven groups of isolated fractions and tested for acaricidal activity.