Biochar-fertilizers interactions study on soil available micronutrients of summer groundnut under south Saurashtra conditions

Abstract

The aim of this study was to evaluate the effect of biochar with organic and inorganic fertilizers on soil micronutrient availability in summer groundnut during 2022 and 2023 at the Instructional Farm, College of Agriculture, Junagadh Agricultural University, Junagadh. The biochar was prepared from cotton stalk and procured from Department of Renewable Energy Engineering, College of Agricultural Engineering and Technology, JAU, Junagadh. Prior to field application, biochar and FYM was enriched with Rhizobium spp. at 2.0 lit., Phosphorus solubilizing bacteria (PSB) at 2.0 lit., Potassium solubilizing bacteria (KSB) at 2.0 lit., Trichoderma harzanium at 2.0 kg., Pseudomonas fluorescence at 2.0 kg, Beauveria bassiana at 2.0 kg per hectare. Ten treatments combinations comprising of cotton stalk biochar at 1.5, 3 and 4.5 t/ha with 100%, 75% and 50% RDF (25:50:50 kg N:P2O5:K2O ha-1) and 5 t/ha FYM. All of these was added as basal application to summer groundnut. 75% RDF with FYM at 5 t ha-1 shows its superiority in respect of DTPA-extractable Fe, Mn, Cu, Zn and B at 30, 60, 90 days after sowing and at harvest under medium black calcareous soil. Further, application of cotton stalk biochar at 4.5 t ha-1 with 100% RDF and 75% RDF also equally effective in soil available micronutrients.