After four leaves stages of tomato plant pathogenicity test was carried out to determine the pathogen responsible for wilt host specific to tomato plant. Mycelium disk of desired pathogen were grown in Armstrong medium broth for seven days in orbital shaker incubator at 28°C. Mycelium mat was collected by centrifugation at 3,000 rpm for 10 min. Mycelium was crushed with autoclaved distilled water in sterilized mortar and pestle under laminar condition to avoid microbial contamination. Different concentration of conidial (107 spore ml-1) suspension of pathogen (F. oxysporum) was taken as 2 ml/100 g, 4 ml/100 g, 8 ml/100 g and 12 ml/100 g substrate. Plant were treated and kept under greenhouse condition until the disease incidence activity was seen, control plants were treated with distilled water alone. Finally, 4 ml (107/ml spores) conidial suspension per 400 g substrate concentration was standardized for disease incidence experiment in tomato plant (Figure 2). The experiment was conducted in 500 g pot filled with sterilized substrate (equal ratio of soil and sand mixture).