Enhancing DAP Fertilizer Efficiency for Calcareous Soil through the Development of Some Reactive Layer Polymer Coatings

Abstract

Growing population of the world has long been linked with the question of food security. To alleviate food insecurity, agricultural framers used a large quantity of artificial fertilizers to fill the gap between food demand and supply. This excess of fertilizer will have several negative consequences for the ecosystem, including contamination of the atmosphere, soil, and water bodies. The poor nutrient use efficiency of phosphatic fertilizers in calcareous soils is a serious worldwide issue, which results in sub-optimal phosphorus (P) availability. This is interlinked with the higher amount of calcium content in soil, that reduces the plant available phosphorus. A mere 15% of the applied DAP fertilizer is accessible to crops due to our soils' calcareous composition, leaving an economic burden of the other 85% on the farmer. Lack of access to essential nutrients reduces productivity and worsens the environment. Among several techniques available for enhancing P-uptake and P efficiency, polymer-coated fertilizers are relatively a new idea for minimizing P-fixation and ensuring a consistent supply of phosphates to growing crops. Keeping in view, a research study was carried out to study the effectiveness of biodegradable anionic polymer-coated di-ammonium phosphate fertilizer to improve the phosphorus availability. Uncoated DAP fertilizer and polymer-coated DAP (C-1 and C-2) were applied on spinach plants to check the growth, yield and P-uptake. Biodegradable anionic polymers include recurring polymeric Subunits preferably made up of Vinylic and dicarboxylic monomer such as Vinyl acetate and maleic anhydride were taken for experiment. SEM Micrographs for morphological characterization indicated a uniform coating of biodegradable anionic polymer on DAP granules. A blank and two coated DAP samples were used with 7 repetitions in a Complete Random Design (CRD) on spinach plants. Different parameters were tested before and after experiments. Results revealed that application of Poly-A coated DAP (C-1) increased plant fresh biomass (10%), dry biomass (18 %) and P-uptake (66%) in comparison to commercially available DAP. Maximum phosphorus uptake (43%) was observed in the treatment of Poly-B coated DAP as compared to uncoated DAP treatment. So, it can be summarized that the quantity of applied P prone to fixation was reduced dramatically with the use of polymer-coated DAP, which is a novel approach that could effectively enhance plant growth, biomass yield, and P-uptake of spinach crops compared to uncoated DAP fertilizer