Abstract
The goal of this study was to enhance the biocontrol efficiency of Trichoderma harzianum JF419706 via its mycoparastic affinity as well as inducing the production of cell wall degrading enzymes. Different carbon and nitrogen sources were added to the growing medium of T. harzianum JF419706 to induce cell wall degrading enzymes. Production conditions of the target enzymes were optimized. The mycoparasitic affinity was induced by induction of the mutation of T. harzianum JF419706 by ethidium bromide and UV radiation. Results indicated that 4 days was appropriate to achieve the maximum production of the enzymes. The slight acidic pH (5.5-6.0) was more favorable for production of enzymes. The results exposed that chitin was responsible for improvement in the productivity of all tested enzymes, except the protease that was improved only by casein. All enzymes exhibited a high level of activity in media supplemented with yeast extract. Ethidium bromide in concentration either 0.5 or 1.0 mg mL(-1) enhanced the mycoparasitic affinity of T. harzianum JF419706 more than UV radiation. However, both treatments enhanced the mycoparasitic affinity of the biocontrol agent compared with the wild type. This observation was confirmed by RAPD-PCR technique using primers chitinase (C15) and R2 that succeeded to differentiate among the mutants and the wild isolate. (C) 2016 Friends Science Publishers