Botanical pesticides as a source of safe bioacaricides for the control of Tetranychus cinnabarinus

The potential of crude extracts from four plant species were evaluated for their ability to control the Tetranychus cinnabarinus mites under controlled conditions. The extracts were prepared from four plant species Artemisia herba-alba, A. leucodes, Eruca sativa and Sinapis alba. The toxicity of the four plant extracts to animal cells was measured in vitro using the vital mitochondrial dye 3-[4,5-dimethyliazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. The assay revealed that the extracts from A. herba-alba, A. leucodes or S. alba were not toxic to animal cells up to concentrations of 100 μg/ ml. Extracts from E. sativa at concentrations > 100 μg/ml were found to significantly reduce cell viability and are therefore toxic to animal cells. The mortality and repellency potential of the different extracts showed that A. leucodes or E. sativa at a concentration of 50 μg/ml resulted in more than 80% mortality and repellency. However, extracts at the same concentration from A. herba-alba or S. alba caused only 58% and 71% mortality and repellency, respectively. These results indicate that further investigations are required to characterize and identify the bioactive ingredients from A. leucodes and E. sativa that revealed greater potential as acaricidal sources for mite control.