Due to the wide range of host-plants and the important role of ecological factors on occurrence and distribution of this disease, our aim was to study their influence on biology of the pathogen. Estimations were made on nutrient medium, temperature and light effects on percentage of germinated conidia and on the way of conidia germination. It can be stated that germination rate was higher in media with better supply of nutrient matters. The highest rate of conidia germination was noticed in tobacco juice and the highest speed of germination in tomato juice. Temperature increase had a positive effect on conidia germination and the optimal temperature was 280C. We also found that germination was higher in dark conditions than in light. We believe that these investigations will contribute to understand the pathology of brown spot disease and to take preventive measures for its control.