The Preliminary Study Of Four Plant Extracts For Acaricidal Activity

The preliminary research results of Northwest A&F University Research&DevelopmentCenter of Biorational Pesticide (RDCBP) in screening of acaricidal activity show that theextracts of four plants Glycyrrhizae uralensis, Tetradium ruticarpum,Sphaerophysa salsulaand Leonurus artemisia (Lour.) SY Hu) have some acaricidal activity. In this paper, based onpreliminary studies, further testing active of these four plant extracts, designed to providebasis for developing new botanical acaricide. Results are as follows:1. The test results of slide immersion showed that all of the acetone extracts of fourplants Glycyrrhizae uralensis,Tetradium ruticarpum, Sphaerophysa salsula and Leonurusartemisia (Lour.) SY Hu have some acaricidal activity, which the L. Artemisia (Lour.) SY Huhas the strongest acaricidal activity, at the concentrate of0.2g DW/ml, the corrected mortalityin24h to Tetranychina harti is78.89%, and the corrected mortality in24h to Tetranychuscinnabarinu is62.92%.2. Taking T. cinnabarinu as the test pest mites, use the slide impregnation method, testthe acaricidal activity of17compounds derived from G. uralensis，T. ruticarpum，S. salsulaand L. Artemisia (Lour.) SY Hu, and found: all of the17species of compound have lowacaricidal activity, but the corrected mortality in24h are less than50%; Evodiamine andIsoquercitrin at the concentrate of1000mg/L, the corrected mortality rates in48h were59.28%and57.54%.3. The screening result of extraction solvent of L. Artemisia (Lour.) SY Hu measuredwith the extract rate and acaricidal activity showed：The highest extraction rate of the fivesolvents is water, the extraction rate is11.19%,the extraction rate of95%ethanol is6.76%;petroleum ether extract has the lowest rate of1.89%. Use the slide impregnation method, inthe form of extract fixed quantity, at the concentrate of0.2g DW/ml, the95%ethanol extractof L. Artemisia (Lour.) SY Hu (Inner Mongolia) presents the best bioactivity to Tetranychinaharti and Tetranychus cinnabarinu. Therefore, choose the95%ethanol as the best solvent. 4. Use the95%ethanol extract of L. Artemisia (Lour.) SY Hu as the test material andthrough screening of the solvent and emulsifier, to develop a environmental EC formulation,and developed a kind of Botanical acaricide, test the quality of the environmental EC andfound to comply with the quality standards of pesticides.Based on the comprehensive analysis of the above results, the acaricidal activityresearch of these four plants on exploitation and utilization in future should focus on thesynergies with other natural products.