Comparison of two antagonist Streptomyces spp. against Rhizoctonia solani causal agent of sugar beet damping-off

In present study two antagonist Streptomyces spp. (isolates S2 and C) have been assayed against three isolates of Rhizoctonia solani (Rs1, Rs2 and Rs3) causal agent of sugar beet damping-off. The in vitro antagonism assays showed that both isolates, S2 and C, have inhibitory effects on fungal mycelium growth. Isolate C was able to produce siderophore but isolate S2 can not. Both isolates showed chitinase activity on colloidal chitin agar. Soil treatment with each of these two biocontrol agents decreased severity of damping-off, increased seedling stand, shoot and root dry weight and root density significantly.

Keywords:

Antagonist , Streptomyces , Rhizoctonia solani , Damping -off , Biocontrol