ABSTRACT

The soil composition and farming practices can affect the soil bacterial communities that carry out nutrient cycling and other functions crucial to crop health and growth. This study was conducted in a field experiment to determine the effects of agricultural soil on bacterial population structure. These effects were associated with soil surface bacterial, growing plant on soil bacterial and about to harvest soil bacterial. The bacterial load were generally increased from surface soil sample followed by growing plant soil sample and the highest found in about to harvest soil sample respectively and bacterial counts are generally higher in the surface soil layer as compared to the lower depths. The cultural morphological, microscopically, biochemical and sugar utilization examinations of isolate were carried out and a total of 17 bacterial strains were isolated comprising of bacillus subtilis (3), Staphylococci aurues (3), Escherichia co/i (5), Pseudomonas (2), Klebsiella (1) and Serrieta (3) respectively. The highest number of isolate were found with Escherichia (29.4%), while the lowest were recorded in Klebsiella (6.0%) respectively. Therefore an increase in bacterial is considered beneficial to the fertility of the soil, while its decline may be considered detrimental if this leads to a decline in biological function. The study point to a need for future research exploring on how (1) farming practices influence bacterial community structure and functions and how soil microbial populations respond to agricultural management practices.