Study of nitrogen fixation bacteria population and determination of suitable medium for growing in saline and non saline soils

摘要

Recently, use of the potential bacteria in agricultural production and preservation of the environment is very important. species of bacteria capable fixed nitrogen of atmosphere and change to form usable plants. So we can used than the bacteria for remove chemical fertilizer and maintain the environment. The aim of the research was study bacteria population in saline (35ds/m)and non saline(3ds/m)soils and determine to the best medium for growth of this bacteria.the first maked four types of mediums growth of nitrogen fixation bacteria with 2 saline and non saline soils treatments and 3 replications .so the liquid mediums at the temperature 30 °C shaked with 150 rpm for 72 hours.after than done dilution for 10-1,10-2,10-3,10-4,10-5 and amount 200 microliter transfered to petri dishes content soild mediums so at the temperature30°C incubated for 72 hourse.finally,after than observation of colonies, numbers them accounted .The results showed that the medium No. 1 hadn't any growth for both saline and non saline soils treatments but medium No.2 had little growth. Medium No 4 had moderate growth but medium No.3 had the best of growth of bacteria. Overall results showed that for having the best growth and proliferation of bacteria must use than suitable nutrient compounds. According to research done the best medium for growth and proliferation this bacteria was medium No.3.