CONFIDOR IN RATOONS FOR CONTROL OF GREYBACK GRUB DAMAGE

Control of greyback canegrub damage can be achieved with Confidor® SC insecticide (200 g imidacloprid/L) applied to the soil in ratoon sugarcane fields, as demonstrated for 19 field trials detailed in this paper. However, responses to treatment were sometimes inconsistent. Rates from 300-400 g ai/ha significantly increased yield as effectively as higher rates. Slightly lower rates were sometimes also effective. Treatments applied between early August and early December were effective, but field conditions may restrict the latest date at which treatment is possible. Application by side-dressing behind coulters no more than 500 mm apart and either side of the row of ratoon shoots was effective and was the most commonly tested, practical and convenient option, although application into a coulter-slot through the middle of the stool was as effective. Delivery of chemical into soil via single-stream jets or fan-jets was equally effective. The industry and suppliers need further research and development with this product to increase the consistency, effectiveness and efficiency with which it could be used.