The effect of nitrogen fertilizer and density unusual levels on plant growth characteristics, grain and forage yields of maize

the experimental was conducted as a split in 20015 in a randomized complete block design with three replications at the Agricultural Research Station, Ferdowsi University of Mashhad. Nitrogen in five levels (0, 150, 300, 450, 600 kg per hectare) and density at three levels (10, 15 and 20 plants per square meter), respectively, of primary and secondary, respectively. As a result, the maximum leaf area index was achieved by consumption of 450 kg of nitrogen per hectare. The lowest growth rate in terms of consumption and the highest figure obtained by applying 450 kg N per hectare. The highest LAI (6.32 unit) and dry matter accumulation (3623 g m-2 day-1) were observed on account of 20 Plant m-2. Irrespective of the plant density, height of corn significantly increased when nitrogen was applied by 450 kg ha-1; however, more nitrogen application had a negative effect on mentioned trait. The highest yield (72.68 tons per hectare) in treatment 450 kg nitrogen per hectare with 20 plants per square meter and the highest grain yield of (10.76 tons per hectare) in treatment 450 kg N ha-1 at a density of 10 plants per meter square was observed. It seems that despite the environmental impacts resulting from the use of nitrogen application up to 450 kg per hectare with a very high density, yield will increase.