Effect of Three Types of Organic Amendments and Nitrate Concentration on Bacterial and Fungal Populations in a Sandy Loam Soil Adamawa State, Nigeria

A pot experiment was conducted at the School of Agriculture Screen House using soil samplescollected from the MAUTECH Farm site at 0-20cm depth to study the effects of cow dung, cowpea straw and maize straw applied as organic amendments and nitrate concentration on soil bacterial and fungal populations. The organic amendments were applied solely as factorial treatments at four levels 0g, 50g, 70g and 100g per 3kg of soil based on a randomized complete block design with three replications. Routine soil physical and chemical analyses were carried out before and after the experiment. Soils were then incubated with the organic amendments and sampled at 7days, 14 days and 21 days after incubation to determine bacterial count (cfu/ml), fungal count (cfu/ml) and nitrate concentrations (mg/kg). Results obtained revealed that the soil is loamy sandy with high porosity and low levels ofsoil organic matter, total nitrogen (2.1mg/kg) and available phosphorus (0.75 mg kg-1) contents. Bacterial and fungal counts were significantly p