Effect of biochar on soil physico-chemical and chemical properties in relation to groundnut growth in red sandy loam soils of North Coastal Andhra Pradesh

Abstract

A field experiment was conducted in red sandy loam soils of North Coastal Andhra Pradesh to study the effect of biochar on soil physico-chemical and chemical properties in relation to growth of groundnut crop (variety K-6) during rabi, 2018-19. Biochar application to soil had significant influence on soil pH, CEC, organic carbon, available nitrogen, available phosphorus and available potassium where as non significant influence on electrical conductivity, available sulphur and micronutrients metal cations viz., Zn, Fe, Mn, Cu was noticed. Soil pH significantly increased when biochar applied @ 6 t ha-1. At harvest stage of groundnut highest soil organic carbon (0.53%) was observed in T8 (75% RDF + biochar @ 6 t ha-1) and lowest (0.32%) in T1 (control). The highest available nitrogen, phosphorus and potassium were observed in T5 (100% RDF + biochar @ 6 t ha-1) @ 191.10, 36.04, 331.77 kg ha-1, respectively and lowest corresponding values were observed in control @ 131.63, 15.48, 207.68 kg ha-1 at peg penetration stage of groundnut. A slight increase in EC and available sulphur and slight decrease in micronutrients was noticed which was non- significant. At pod development stage highest leaf area index (3.16) was recorded in T5 treatment (100% RDF + biochar @ 6 t ha-1) which was significantly higher than T1 (control) @ 2.40. In general the dry matter accumulation increased from peg penetration to pod development stage of groundnut. Highest dry matter accumulation of 2950.90 kg ha-1 and 6427.54 kg ha-1, respectively at peg penetration and pod development stage was observed in T5 (100% RDF + biochar @ 6 t ha-1) which was on par with T3 (100% RDF + biochar @ 2 t ha-1), T4 (100% RDF + biochar @ 4 tha-1), T8 (75% RDF + biochar @ 6 t ha-1) treatments.