Effectiveness of some biocontrol and chemical treatments against Heterobasidion annosum on Norway spruce stumps

The biocontrol agents Trichoderma harzianum, Verticillium bulbillosum, Hyph oloma fasciculare, Phanerochaete Vuiileminia comedens together with the che mical treatments propiconazole and the culture filtrate of V. bulbillosum w ere tested on Norway spruce stumps during 2 years in order to evaluate thei r effectiveness against Heterobasidion annosum. The results were compared, in 1 year, with the effectiveness of Phlebiopsis gigantea. All the treatmen ts reduced H. annosum infections. The best results were obtained with P. ve lutina, propiconazole and with culture filtrates and conidial suspensions o f V, bulbillosum.