EFFECTS OF FILMCOATING BRUSSELS-SPROUTS SEEDS WITH VARIOUS INSECTICIDES ON THE TRANSPORT INTO THE SEEDLINGS AND ON THE CONTROL OF CABBAGE ROOT FLY, DELIA-RADICUM (B)

Brussels sprouts seeds (Brassica oleracea L. var. gemmifera (D.C.) Sch ulz) were filmcoated in 1990 and 1991 with various doses of the insect icides chlorpyrifos, isofenphos and fonofos. The plants had been raise d in modules. Different times after sowing, the amount of chlorpyrifos (filmcoating containing 28.8 g a.i./kg seed) and isofenphos (filmcoat ing containing 20 and 30 g a.i./kg seed) in the root and the stem, in the cotyledons and in the leaves was detected during 1991. No or littl e isofenphos was detected in the different parts of the seedlings, on the or-her hand, considerable concentrations of chlorpyrifos were dete cted in the root and the stem 48 and 56 days after sowing. Protection against cabbage root fly was assessed at a location with a high popula tion density of cabbage root fly. Control of the cabbage root fly by a filmcoating containing chlorpyrifos 9.6 g a.i. per kg seed was as eff ective as treating each plant after transplanting. It is concluded tha t filmcoating with chlorpyrifos for the control of cabbage root fly en ables the possibility for a large reduction in pesticide use without l oss of control.