NEW BIOTYPES OF TRICHODERMA SPP EFFECTIVE IN INDUCING RESISTANCE ACTIVATION AGAINST Rhzioctonia solani CASUAL AGENT IN BEAN PLANTS Phaseolus vulgaris.

The results showed that application of the bioagents Trichoderma spp. isolates as a conidial suspension greatly reduced the percentage of disease and the disease index caused by R. solani in bean plants at different rates. The most effective Trichoderma spp. isolates were Thk20 Thk80 which reduced disease percentage to 23% and Thk80 32% and disease index to 0.27 and 0.34 respectively. The results indicate that isolates Thk20,Thk80,Th1 and T.viride have a strong tendency to induce resistance against R.solan.The isolate Thk 20 differed significantly and caused significant raising in Peroxidase activity 18.3 /min/g f.w follow that the isolates Th1 and T.viride 11.48 and 8.45 /min/g f.w .Thk20 and Th1 isolates differed significantly and caused significant raising Poly Phenol Oxidase activity with 0.265 and 0.189 /min/g f.w while the isolate T.viride caused significant raising in Catalaze activity with 13.85/min/g f.w, following that the isolates Thk20 and Th1 with 12.81 and 9.45/min/g f.w respectively . Thk20 spores were exposed to UV aiming a new biotypes which were segregate by its ability to grow on CM medium The new biotypes were tested for their efficiency as bio-control agents and as a plant growth promoter. The results showed that biotypes N7,N8,N9,N10,N15,N16 and N22 caused significant reduction in disease percentage but showed no significant differences with parent isolate Thk20. The biotype N8 succeeded in reducing the disease index to 0.4 .The results Strongly suggest that biotypes N8,N9,N15, and N22 have a propensity to induce resistance against R. solani which is reflected in significant increase of Peroxidase, Poly Phenol Oxidase and Catalaze activity.