Published online by Cambridge University Press: 31 May 2012
In the laboratory, endosulfan and phosalone were non-toxic to adult Pterostichus melanarius and Harpalus affinis and of relatively low toxicity to Amara spp. Phosmet was non-toxic to P. melanarius but was toxic to Amara spp. and to a lesser extent to H. affinis. Azinphos-methyl, permethrin, and dimethoate were considerably more toxic to the latter two species than to P. melanarius. Diazinon was toxic to all species and methyl and ethyl parathion were highly toxic to P. melanarius. Bembidion quadrimaculatum was susceptible to most insecticides except endosulfan and phosalone. Mortality in the field generally supported laboratory findings. Diazinon caused the greatest mortality to all species and permethrin caused some mortality to all species. Phosmet was highly toxic to H. affinis and Amara spp. Generally the toxic effects of the insecticides were of relatively short duration.