Effect of foliar application of nitrogen-phosphorus-potassium fertilizers on nutrient uptake and protein content of maize

The effect of foliar application of nitrogen-phosphorus-potassium (NPK) fertilizers on nutritional status and yield of maize (Zea mays L.) were investigated through a study conducted in a zonal agricultural research station of University of Agricultural Sciences, GKVK Bengaluru (India). The experiment was laid out in randomized complete block design. The treatments consisted of two levels of soil application (75 and 100%) of recommended dose of fertilizer (RDF) and foliar applications of NPK (19:19:19). The fertilizers were applied at 6-leaf, tasselling, knee height and tasseling growth stages. Nutrient uptake, protein content and available soil nutrients at harvest were analyzed. Results indicated that soil application of 100% RDF along with foliar sprays of NPK at knee height and tasselling stages significantly produced the highest levels of N, P and K uptake (306.60, 100.57 and 216.24 kg ha-1, respectively) and maximum protein content (11.5%). Use of this fertilizer treatment also resulted into highest available soil N (273.74 kg ha-1), P (59.45 kg ha-1) and K (204.88 kg ha-1). The combined soil application of 100% RDF and foliar application of NPK at knee height and tasseling stages has potential to increase nutrient supply and protein content of the maize crop. Key words: Maize, foliar application, NPK, nutrient-uptake, protein content.