بررسی خواص آنتاگونیستی قارچ Trichoderma sp. دربرابرگونه غالب فوزاریوم های (Fusarium spp) عامل پژمردگی فوزاریومی درختان سرو فضای سبز

Today, biological control of pathogenic agents with the aim of reducing the dangerous effects of chemical insecticides, including threats to human health and environmental pollution, is considered a priority. Cypressus is one of the most valuable trees that is widely cultivated in the green space and many different microorganisms cause its drying. It has the ability to inhibit the growth and proliferation of important soil-borne plant pathogenic fungi. The isolates were obtained from the country's herbal research institute. In this research, the inhibitory effect of the antagonistic isolate Trichoderma harzianum on the fungus Fusarium oxysporum, which causes root and ring rot of cypressus trees, was investigated in greenhouse conditions. The greenhouse experiment was repeated twice in the form of randomized complete block design with 12 treatments and three replications. The experimental treatments were: pathogen-infected control in sterile and non-sterile soil, non-infected control in sterile and non-sterile soil, antagonist treatment in sterile and non-sterile soil, antagonist treatment with pathogen in sterile and non-sterile soil. The inoculum of each of the fungal isolates was used at the rate of 5 cc per kilogram of the soil of the pots and simultaneously. Sarbin seedlings were used in this test. The data obtained from measuring wet and dry weight indices of roots and aerial parts were recorded after 45 days. Statistical analysis of the data obtained from the measurement of indicators was done using SPSS software. In greenhouse conditions, the antagonist isolate in the presence of the pathogen reduced its adverse effects, which increased the fresh and dry weight of roots by 56.4% and 52.1%, and the fresh and dry weight of aerial organs by 23.4% and 12.7%. compared to the witness.