Performance of Groundnut (Arachis hypogaea L.) as Influenced by Integrated Nutrient Management under Fertigation

Abstract

Background: Groundnut (Arachis hypogaea L.) is a prominent legume oilseed after mustard in India and it’s lower productivity is a matter of concern attributed to the major constraints of inefficient irrigation and nutrient management in rabi season. Fertigation is the recent innovative gearing up technology in which the nutrients are applied in précised quantity along with drip irrigation at regular intervals throughout the crop growth matching with their requirement, resulting in enhanced resource use efficiency and crop yields. Liquid formulations of biofertilizers can be diluted sufficiently and applied through drip irrigation uniformly to the root zone of crop. Humic acid is widely used as fertilizer synergist and hence in combination with inorganic fertilizers can enhance their use efficiency and improve root zone activity. The present experiment was conducted to develop an integrated nutrient management practice in combination of chemical fertilizers with organic sources i.e., co-inoculation of liquid biofertilizers and humic acid under fertigation for rabi groundnut under irrigated condition. Methods: The experiment was comprised of seven treatments of integrated nutrient management practices viz. T1-Soil application of 100% RDF (30-40-50 kg N, P2 O5 and K2 O ha-1) + drip irrigation; T2-75% RDF + liquid biofertilizers @ 3.75 l ha-1; T3-75% RDF + humic acid @ 12.5 l ha-1; T4-50% RDF + liquid biofertilizers @ 3.75 l ha-1; T5-50% RDF + humic acid @ 12.5 l ha-1; T6-100% RDF + liquid biofertilizers @ 3.75 l ha-1; T7-100% RDF + humic acid @ 12.5 l ha-1 which were tested in randomized block design with three replications. Result: The integrated nutrient management practice with 30-40-50 kg N, P2 O5 and K2 O + liquid biofertilizers @ 3.75 l ha-1 (Rhizobium, Phosphorus solubilizing bacteria and Potassium solubilizing bacteria each @ 1.25 l ha-1) through fertigation recorded tallest plant height (49.9 cm), maximum LAI (2.05), SCMR value (34.5), number of nodules plant-1 (60.2), pods plant-1 (11.2), 100 pod weight (125.7 g), kernel weight (52.9 g) which resulted in highest pod yield (3902 kg ha-1), seed yield (2666 kg ha-1), haulm yield (4363 kg ha-1), higher nutrient uptake (77.3 kg N, 18.9 kg P and 57.8 kg K ha-1) and net return (Rs. 130818 ha-1) of groundnut, which were comparable to 100% RDF + humic acid @ 12.5 l ha-1.