The effects of foliar fungicides on some insect pests of cereals.
The effects of foliar fungicides on Lema melanopa, Sitobion avenae and Metopolophium dirhodum were investigated in laboratory trials. Contact with benomyl did not reduce the hatchability of Lema eggs but the survival of larvae hatching from treated eggs was lower than in the controls. Contact with benomyl did not reduce the survival of Lema adults but increased the mortality of newly hatched larvae. Similarly, the mortality of Lema larvae reared on barley leaves treated with benomyl was greater than in the controls. The contact toxicity of benomyl to adults and nymphs of M. dirhodum was high and the survival of M. dirhodum and S. avenae was reduced when reared on leaves treated with benomyl. Both benomyl and carbendazim reduced the reproductive rate of S. avenae and M. dirhodum but triadimefon did not affect either species.