Eficiência do Bacillus thuringiensis var. kurstaki (Berliner, 1915) no controle da traça da cera Galleria mellonella (Linnaeus, 1758) (Lepidoptera: Pyralidae)

Abstract

This research aim at evaluating the efficiency of Bacillus thruringiensis var. kurstaki (Berliner) in the control of Galleria mellonella (Linnaeus).The experiments were conducted in the Insect Biology Laboratory of the Entomology Department of the Universidade Federal de Lavras – UFLA, Lavras, MG, Brazil, at 28±2ºC, RH 70±10% and 12-hour photophase. Commercial formulation of B. thuringiensis. var. kurstaki was applied through spraying, comb soaking and also incorporated into the artificial diet fed to third instar caterpillars of the greater wax moth. Application of B. thuringiensis var. kurstaki through the spraying of the combs was efficient for control, reaching levels equal or larger than 85% of mortality when 5 g/100 mL of water were utilized. In the application by soaking of the combs all the dosages tested were efficient reaching up to 100% of mortality. Added to the artificial diet, the concentration with the greatest percentage of mortality was of 10 g/60 g of diet. Symptoms of infection by B. thruringiensis were identified both in the caterpillars and the isolation of the bacterium through a culture of Bacillus, proved to be the responsible of mortality of those insects at all the dosages of commercial formulation of B. thuringiensis var. kurstaki utilized.