Study of Nitrogen Fertilization Management on Corn Yield and Nitrogen Use Efficiency in the Southern Caspian Sea Region

Research was conducted at the Mazandaran Agricultural Research Center (Gharakhil) from 2016 to 2018 on the effect of nitrogen consumption time and amount on the yield and efficiency of nitrogen consumption in corn. A complete block design with four replications was used. Treatments include N1: no fertilizer application (control); N2: 60 kg ha-1 nitrogen fertilizer application in pre-plant; N3: 120 kg ha-1 nitrogen fertilizer application in pre-plant; N4: 180 kg ha-1 nitrogen fertilization in pre-plant; N5: 60 kg ha-1 nitrogen application in two stages [50% in pre-plant + 50% in R1(silking)]; N6: 120 kg ha-1 nitrogen fertilizer in two stages [50% in pre-plant + 50% in R1(silking)]; N7: 180 kg ha-1 nitrogen fertilization in two stages [50% in pre-plant + 50% in R1(silking)]; N8: 60 kg ha-1 nitrogen in three stages [33.33% pre-plant + 33.33% in R1 (silking) + 33.33% in R3 (milk)]; N9: 120 kg ha-1 nitrogen fertilizer in three stages [33.33% pre-plant + 33.33% in R1 (silking) + 33.33% in R3 (milk)]; N10: 180 kg ha-1 in three stages [33.33% pre-plant + 33.33% in R1 (silking) + 33.33% in R3 (milk)]. The agricultural activities were conducted according to regional customs. Based on the results, different levels and times of consumption affected the chlorophyll index yield and nitrogen use efficiency significantly. The highest grain yields were obtained by applying 120 kg ha-1 of nitrogen before planting, and the chlorophyll index was found to be positively related to grain yield.