Test on the control of the pine processionary caterpillar with Bacillus thuringiensis

Abstract

During 1995-1997 trials were carried out to control Thaumetopoea pityocampa in two pine stands, the first sited in the Maremma Natura1 Park (Grosseto), the second on the outskirts of Florence. Tests were carried out on the 2^nd and 3^rd instar larvae in autumn and on the 4^th generation larvae in winter. Dimilin was applied at the rate of 0,25 g/l and Bacillus thuringiensis (Biobit and Thuricide) at the rates of 1,5 g/l in autumn and 3 g/l in winter. Low effectiveness resulted in the late winter for Bacillus thuringiensis and high mortality rates (from 63,22 to 91,96) were obtained in autumn with both synthetic and biologica1 compounds. Thuricide appeared to be more effective than Biobit.