Effect of mode and source of iron nano particles on the biological properties of the calcareous soil

The effect of mode and source of iron application on biological properties was evaluated in the green house experiment along with the different sources i.e. nano Fe2O3 and FeSO4 in the calcareous soil with wheat as test crop during kharif season of 2014, New Delhi. Application of FeSO4 through both soil and foliar modes significantly increased the dehydrogenase activity by 53 and 38%; whereas application of iron nano particles at 0.3 mg Kg-1 though soil enhanced the activity by 26% over the control. Foliar application of 0.2% mg Fe either through FeSO4 and Fe2O3 (nano) doses were exhibited the similar response of towards the microbial biomass carbon during the entire crop growth stages. Salts of FeSO4 and nano Fe2O3 did not influence both the bacterial and fungal population in the calcareous soil. Overall results revealed that the application of lower doses of nano Fe2O3 through foliar and soil showed non-significant and negative impact on soil biological properties.