STRAIN IMPROVEMENT BY PROTOPLAST FUSION FOR ENHANCEMENT OF BIOCONTROL POTENTIAL INTEGRATED WITH FUNGICIDE TOLERANCE IN TRICHODERMA SPP

摘要

From 10 isolates of Trichoderma spp., T. harzianum an efficient antagonist and T. longibrachiatum tolerant to copper sulphate and carbendazim were selected as the two parent strings for strain improvement by protoplast fusion. Protoplasts of the two isolates from young mycelia following cell wall digestion by Novozym 234 were fused using polyethylene glycol (PEG) in 10 mmol/l CaCl2 and 10 mmol/l Tris-HCl at pH 7.5. The results are single fusants colonies were selected from the numerous fusants that 1 resulted. Two fusants F1 and F2 which exhibited an enhanced antagonistic potential against Rhizoctonia solani, Fusarium oxysporum f. sp. lycopersici. Venturia inaequalis, Curvularia lunata and Bipolaris oryzae along with tolerance to copper sulphate and carbendazim were selected.