Five grams of soil from the rhizosphere were suspended in 45 ml of sterile distilled water in a 250-ml Erlenmeyer flask and shaken for 15 min at 150 strokes per min at room temperature. The suspension was serially diluted in distilled water and plated onto NA plates containing 20 μg ml−1 of bacitracin and 5 μg ml−1 of phosphonomycin. The plates were incubated at 30 °C, viable cells were counted after 24 h, and the cell number was expressed as the total cell number. To determine the number of spores, 1 ml of the suspension was heated for 15 min at 80 °C, serially diluted, and spread onto NA plates. All data are expressed as CFU per gram of dry soil.