PYRIDAZINONE DERIVATIVES AS ACARICIDES AGAINST DERMA TOPHAGOIDES MITES

Abstract:
Two pyridazinone derivatives, pyridaben and NC- 194, were found by medium mixing test to be potent chemicals which inhibited the growth of Dermatophagoides population. Pyridaben {2-tert-butyl-5- (4-rerz-butybenzylthio)4chloropyridazin-3-(2H)-one}, which is a new agricultural acaricide, suppressed 90% of the population growth of D. farinae at 50 ppm in 4 weeks. NC-194 12-tert-butyl4chloro-5-[2- (2,6-dimethyl-4-phenoxyphenoxy)ethylthio]pyridadne-3(2H)-one), which is being developed as an agricultural insecticide, suppressed more than 90% of the population growth of both D. farinae and D. pteronyssinus at 25 ppm during 4 weeks. Pyridaben and NC-194 thus are highly active in curbing the population growth of Dermatophagoides mites and are expected to be superior acaricides for control of these mites.