Effects of fresh cattle manure on the composition of non-fermenting Gram-negative bacteria in soil, and vice versa

We examined the composition of non-fermenting gram-negative bacteria in laboratory microcosms established with fresh manure (dairy cow) and soil from two farms (S and B). 50-100 µL of solution, prepared from 5g of soil or manure in 45 ml sterile 0.9 % NaCl, were inoculated on CHROMagar Acinetobacter for every treatment (see below), incubated for 18 to 24 h incubation at 28 ºC. After DNA extraction, we sequenced the 16S rRNA gene (515F-806R primers) to identify bacterial taxa in 174 samples, including control manure (Ex), manure on natural soil (C1) and manure on gamma-irradiated soil (D1); control soil (A), natural soil under manure (C2) and gamma-irradiated soil under manure (D2). Microcosms were sampled on days 2, 7, 14, 28 and 84. Two independent experiments were set up using soil from farms S and B. Three replicates per treatment, time and experiment were sampled.