Cabbage root fly control using non-organophosphorus insecticides

The need to find non-organophosphorus insecticides to control the cabbage root fly has never been so urgent. Of the six non-OP insecticides tested, fipronil was the most effective but spinosad, diflubenzuron and cyromazine also showed considerable promise. As expected, the transplant drenches (34 mg active ingredient (a.i./plant) were more effective than the module drenches (5 mg a.i./plant), which in turn were more effective than the film-coated seed treatments (0.001 mg a.i./plant), simply because of the different amounts of insecticide applied per plant. One remaining major problem is that, even if effective non-OP insecticides can be found, the manufacturers may still not support their insecticides being applied to minor crops such as field vegetables.