Effect of Nitrogen on Yield and Some Quality Parameters of Sweet Corn

Abstract

Sweet corn consumption has increased considerably worldwide. Sweet corn is produced for human consumption as either a fresh or a processed product. The nutrient composition of sweet corn is very important for human health and diet. This study aimed to determine the best nitrogen (N) dosage for sweet corn. Kernel mineral composition and protein content were determined for different N rates. The research was carried out during 2003 and 2004 in Sanliurfa, Turkey. Nitrogen application rates were 120, 160, 200, 240, 280, 320, and 360 kg N ha−1 with control. The fresh ear yield per hectare and the protein and mineral contents of kernel were significant (P < 0.01). The lowest yield was obtained at low N applications, whereas increasing N applications increased the fresh ear yield and protein content of kernel. Nitrogen-use efficiency increased up to 320 kg ha−1 N dosage (60.2% and 58.6% for 2003 and 2004, respectively), and a decrease was seen at 360 kg ha−1 N dosage. Leaf area index and root dry matter increased with increasing N supply. The copper concentration of the kernel was generally positively affected by increasing N application. Iron and zinc contents of kernels increased, whereas manganese content decreased, with increasing N doses. At the focus of regression analysis, the best N dosage was 320 kg ha−1 along with the soil N content for Vega sweet corn variety grown in the southeastern Anatolia region of Turkey.