Effect of Different Levels and Times of Nitrogen Application on Grain and Forage Quality of Sweet Corn (Zea mays L. saccharata)

This field experiment conducted during the rabi season of 2017-18 at N. M. College of Agriculture, Navsari Agricultural University, Gujarat, aimed to investigate the response of sweet corn (Zea mays L. saccharata) to different levels and times of nitrogen application under the south Gujarat conditions. The factorial randomized block design (FRBD) with three replications was employed, considering four nitrogen levels (90 kg/ha, 120 kg/ha, 150 kg/ha, and 180 kg/ha) and four split application treatments (½ basal + ½ at knee height, ½ basal + ¼ knee height + ¼ tasseling, 1/3 basal + 1/3 knee height + 1/3 tasseling, and ¼ basal + ½ at knee height + ¼ tasseling). The results of the study demonstrated that the application of 180 kg/ha nitrogen significantly increased the protein content in grain and fodder (10.51% and 3.88% respectively) and total sugar content (14.96). Additionally, higher NPK uptake and available nitrogen (197.25 kg/ha) and phosphorus (47.53 kg/ha) levels were observed with a 180 kg/ha nitrogen application rate. When nitrogen was applied in three splits, specifically at ¼ basal + ½ at knee height + ¼ tasseling, it resulted in significantly higher protein content in grain and fodder (9.89% and 3.54% respectively), total sugar content (13.65), as well as NPK uptake in grain and fodder and available nitrogen and phosphorus (189.95 kg/ha and 45.84 kg/ha). These findings highlight the importance of nitrogen management in sweet corn cultivation to enhance the nutritional quality and productivity of both grain and fodder. Implementing the optimal nitrogen levels (180 kg/ha) and split application timings (¼ basal + ½ at knee height + ¼ tasseling) can contribute to achieving desirable protein and sugar content, as well as improving NPK uptake and availability of nitrogen and phosphorus.