Effects of Biochar on the Abundance of Three Agriculturally Important Soil Bacteria

An in vitro study was conducted to make a comparative study of biochar and biomass on soil bac-teria. The responses of three agriculturally important bacteria viz., Bradyrhizobium, Sulphate re-ducing and Iron oxidizing bacteria, were studied. Total viable counts were also made. Three dif-ferent types of biomasses viz., rice husk, rice straw and saw dust, and biochars produced thereof were used for the study. The biomasses or biochars were applied to the soil at a rate of 5 t/ha. The study included seven different treatments of biomasses and corresponding biochars including a control. Total counts were made on the original materials as well as on the treated soils at 30, 60 and 90 days of incubation. Bacterial count was higher in all the biomass treated soils than the cor-responding biochar treated ones including control. Although the presence of Bradyrhizobium, sulphate reducing and iron oxidizing bacteria were not noted in the fresh soils, their presence, however, was noted after incubation periods. The counts of all three bacteria are however lower in the biochar treated soils than the corresponding biomass treated soils. The paper discusse