EFFECT OF HEAVY-METALS (PB, ZN, CU AND CD) ON MYCELIAL GROWTH OF CYLINDROCARPON-DESTRUCTANS (ZINSSM) SCHOLTEN

Studies were carried out on the effect of heavy metals (Pb, Zn, Cu and Cd) on mycelial growth (both colony diameter and dry mass of mycelium) in three isolates of Cylindrocarpon destructans (one - non-pathogenic and two - pathogenic to fir and pine seedlings). The inhibitory effect of heavy metals on mycelial growth increased in the following order: Pb < Zn < Cd < Cu. The relationship between dry mass of mycelium and colony diameter was evaluated by cubic regression equations. Analysis of variance (ANOVA) has shown that effects of heavy metal concentrations on mycelial growth were stronger than those of the isolates. The general heavy metal tolerance was in the following order: isolate No. 6 > No. 8 > No. 1 (non-pathogenic).