Report 
  Title  
  PYRIDAZINONE DERIVATIVES AS ACARICIDES AGAINST DERMA TOPHAGOIDES MITES
  Key Words  
  Pyridaben, fenitrothion, dust mites
  Author  
  T. SHONO, M. TAKAHASHI AND T. UMEHARA
  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.