Comparative effectiveness of an integrated pest management system for managing the insect pests on cabbage in Guam

The effect of biorational and synthetic organic insecticide application regimes were evaluated for the management of key pests of cabbage in Guam in 2008 and 2009. Cabbage plants were grown in small replicated plots and pests were managed either under a regime of synthetic organic insecticides popularly used by growers (malathion or carbaryl) or biorational techniques, dipel Bacillus thuringiensis and neem (Aza-Direct). Effectiveness of the treatments was evaluated by estimating the population density and marketable- yield levels. The biorational treatments were significantly more effective than the synthetic organic insecticides in controlling lepidopterous pests. Biorational methods (three sprays of neem + three sprays of dipel, on rotation basis) at 15, 30, 45, 60, 75 and 90 days of transplanting resulted in greater marketable yield than the synthetic organic insecticides.