Laboratory and Field Evaluation of Bacillus Thuringiensis Berliner Products against the Teak Defoliator, Hyblaea puera Cramer

Commercial Bacillus thuringiensis (B.t.) Berliner products, namely Delfin®, Agree®, Halt® and Spicturin® were evaluated in the laboratory and on an intensively managed teak plantation for the control of the teak defoliator, Hyblaea puera Cramer (Lepidoptera: Hyblaeidae). A 2 g/litre concentration showed highly significant lethality against defoliator larvae, the early instars being more susceptible (99.8% mortality) than late ones (63.6–81.2% mortality). The order of effectiveness was Delfin = Agree > Halt > Spicturin. At 2 g/litre the B.t. preparations were as effective as at 0.07% (2 ml/litre) monocrotophos 36 % when sprayed on one-year-old saplings in a plantation. However, at 1 g/litre concentration, monocrotophos 0.07% was superior to the B.t. products.