evaluation of growth increasing effect of trichoderma harzianum on tomato

in the present study, effect of five isolates of trichoderma harzianum on growth parameters of tomato was carried out as cr design with six replications under greenhouse conditions. the concentrations 0.5%, 1% and 1.5% inoculums per pot were used. plant length, shoot and root fresh/dry weight, number of leaves and stem diameter as growth parameters were measured. the results showed that isolates were significant at levels 0.05 and 0.01 byduncan multiple rang test (dmrt) for their effects on growth parameters of tomato. isolate t1 had the most growth effect with growth increase of 12.18% at shoot fresh weight, 15.41% at shoot dry weight, 12.70% at root fresh weight, 16.11% at root dry weight, 20.41% at leaf number, 2.50% at stem diameter and 18.51% at plant length. the isolates also showed the most growth increasing at concentration 1.5%. potential using of these isolates as plant growth promoting has been discussed in this paper.