Effect of Foliar Application of Micronutrients and NPK on Available Soil Nutrients in Rice Bean (Vigna umbellata L.)

Abstract

Foliar application of micronutrients is more beneficial than soil application. Since application rates are lesser as compared to soil application, the same quantity of nutrient application could be supplied easily and crop reacts to nutrient application immediately. One of the limiting factors for low yield is to be imbalance and indiscriminate use of fertilizers and emergence of micronutrients deficiencies. The present study aimed to determine the effect of macro and micro nutrients on available soil nutrients in Rice bean (Vigna umbellata L.). An experiment was conducted at College of Agriculture, Kalaburagi, during Kharif 2023. The experiment was laid out in Randomized Complete Block Design (RCBD) with eleven treatments and replicated thrice. The soil parameters such as pH, Electric Conductivity, Organic carbon content, Free calcium carbonate (%), Available Nitrogen, Available Phosphorus, Available Potassium, Available soil sulphur, Exchangeable Calcium and Magnesium were measured by Using standard protocol of APHA (1995). The experimental results revealed that 100% RDF as basal dose + 0.5 % Zinc sulphate (21%) + 0.5 % Ferrous sulphate (20.1%) foliar application at 25 and 50 DAS recorded significantly higher available soil nitrogen (234 kg ha-1), available phosphorus (32.06 kg ha-1), available potassium (344.71 kg ha-1) and available sulphur (22.65 kg ha-1) in rice bean crop. Further, exchangeable calcium and exchangeable magnesium is non significantly with foliar spray of 100% RDF + 0.5 % Zinc sulphate (21%)+ 0.5 % Ferrous sulphate (20.1%)) foliar application however which was on par with the treatments foliar spray 75% RDF + 0.5 % Zinc sulphate (21%)+ 0.5 % Ferrous sulphate (20.1%)) the treatment with foliar spray of 100% RDF + 0.5 % Zinc sulphate (21%)+ 0.5 % FeSO4. In contrast, lower values for available soil nutrients were recorded in the absolute control treatment. Application of 100% RDF and foliar spray of 0.5 % Zinc sulphate (21%) and Ferrous sulphate (20.1%) at 25 and 50 DAS was found to be at par with 75% RDF along with foliar spray of 0.5 % Zinc sulphate (21%) and Ferrous sulphate (20.1%) at 25 and 50 DAS in terms of available macro and micronutrients in soil after harvest of rice bean crop. Hence, for effective crop management to rice bean crop, application of 75% RDF and foliar spray of 0.5 % Zinc sulphate (21%) and Ferrous sulphate (20.1%) at 25 and 50 DAS was recommended.