Band incorporation of fluazinam (Shirlan) into soil to control clubroot of vegetable brassica crops

Abstract

Commercially suitable methods for application of fluazinam were evaluated in field trials conducted in Victoria and Western Australia. Incorporation of fluazinam into the soil in bands 23 cm wide along the transplant row (to a depth of about 15–20 cm) immediately before transplanting was the most effective method of application. Plants grown in soil treated in this way developed significantly less clubroot than when fluazinam was applied using either a spot drench (100 mL/plant) or a continuous spray over the plants immediately after transplanting. The banded soil incorporation treatment consistently increased the marketable yield of broccoli and cauliflower. In one trial, banded soil incorporation increased the marketable yield of both crops by at least 80% compared with the other commercial methods of application currently in use. The banded soil incorporation treatment was more reliable and effective in a range of soil types than the high volume drenches currently used. This method of application remained effective, significantly reducing clubroot severity, when the volume of water used to apply fluazinam was reduced by 80% from 2500 to 500 L/ha.