Effect of Foliar Nitrogen and Basal Phosphorus Fertilization on Growth and Nutrient Uptake of Soybean in Vertisols of the Mewar Region

The soybean plant frequently suffers substantial losses of flowers and immature pods, with fewer than one-quarter of the flowers ultimately developing into pods. Soybean gives higher positive response to applied nitrogen over symbiotically fixed atmospheric nitrogen through its roots alone which proves that nitrogen fixed by soybean roots is not enough for its growth and development. The present study aimed to determine the effect of Foliar Nitrogen and Basal Phosphorus Fertilization on Growth, Yield, and Nutrient Uptake of Soybean in Vertisols of the Mewar Region. The investigation was carried out at Instructional Farm, Rajasthan College of Agriculture, Maharana Pratap University of Agriculture & Technology, Udaipur. This experiment was conducted in split plot design with foliar nitrogen application and basal phosphorus with 24 treatment combinations. The significantly higher chlorophyll content, leaf area index, biological yield and nutrients uptake (nitrogen, phosphorus and potassium) was obtained under 2.5% nitrogen through urea foliar fertilization in the main plots and 100% recommended dose of phosphorus through single super phosphate in subplots over rest of the treatments. highest phosphorus uptake by soybean was recorded with the foliar application of nitrogen through urea (2.5%), which was foliar application of nitrogen through urea (1.5 and 1.0%) and control but remained statistically at par with the foliar application of nitrogen through urea (2.0 and 3.0%). The improvement in phosphorus uptake can be indirectly linked to better nitrogen availability, which enhances root growth and improves phosphorus uptake by stimulating the activity of phosphate-solubilizing enzymes and root exudates. The harvest index, physical properties of soil i.e., density, porosity, water holding capacity, physico-chemical properties i.e., pH, EC, organic carbon didn’t influence significantly with various doses of foliar fertilization of nitrogen and basal phosphorus application. The lowest parameters i.e., chlorophyll content, leaf area index, biological yield and nutrients uptake was obtained control treatments. Based on the findings, it is recommended that foliar fertilization with 2.5% urea along with 100% basal phosphorus should be adopted for enhancing soybean productivity and nutrient use efficiency without adversely affecting soil health.