The effect of combined application of nitrogen fertilizer and Azotobacter at different plant densities on some quantitative and biochemical characteristics of spring corn (Zea mays L.)

To study the effects of combined application of nitrogen and Azotobacter at different plant densities on some quantitative and biochemical characteristics of spring corn, a split plot experiment was carried out in the form of randomized complete block design with three replications in Shoshtar. The treatments of the study were the combination of nitrogen and Azotobacter fertilizer at three levels: the main plot was %100 nitrogen as urea fertilizer, %70 nitrogen as urea Azotobacter, and %40 nitrogen as urea Azotobacter as the main factor and the subplot was plant density at three levels: 6 plants per square meter, 8 plants per square meter, and 10 plants per square meter. Characteristics such as seed yield, yield component, protein, and starch percentage were evaluated. The effects of nitrogen fertilizer and Azotobacter were significant on all traits. The highest seed protein contents were recorded in the treatments of %100 nitrogen as urea fertilizer and %70 of nitrogen as urea and the rest as Azotobacter. The highest average grain yield (552.6 grams per square meter) was obtained from %100 nitrogen treatment and the lowest level (376.7 grams per square meter) was recorded in %70 nitrogen and %30 Azotobacter treatment. Therefore, the combination of biological and chemical nitrogen fertilizers can also improve the efficiency of production and absorption of the sufficient nitrogen fertilizer to reduce nitrogen consumption which contribute significantly to a healthy environment and is an important strategy toward sustainable agriculture.