Integrated Application of Different Nitrogen Sources on Yield and Nitrogen Uptake in Forage Corn (Zea mays) in Rasht Region

The effects of chemical, biological and manure fertilizers combination on corn (SC.704) yield and nitrogen uptake was investigated in a field experiment at faculty of Agriculture, University of Guilan in 2011. The experimental design was conducted as randomized complete blocks design with ten treatments in three replications. Treatments included: no- fertilizer (control), %100 chemical fertilizer (150 kgN/ha and 40 kgP/ha), biofertilizer (Pseudomonas fluorescens Azospririllum brasileneset), manure (28 ton/ha), and different proportion of these fertilizers (seven levels. Results showed that dry matter yield in %100 chemical, %50 manure %50 chemical and biofertilizer %50 chemical treatments were not significant difference. The highest of leaf number and stem diameter and lowest leaf defoliation were obtained in %100 chemical fertilizers, %50 manure %50 chemical treatments. Also chemical , %50 manure %50 chemical, biofertilizer %75 chemical and biofertilizer %50 chemical were produced the highest protein yield and plant nitrogen absorption. The highest nitrogen ues efficiency, nitrogen agronomic efficiency and nitrogen uptake efficiency (95/13, 1.17 and 42.17 respectivley) were achieved in biofertilizer %50 chemical treatment, and the highest nitrogen utilization efficiency and nitrogen physiological efficiency was taken in biological treatment. Finally Results showed that dry matter and protein yield in %100 chemical and % 50 chemical biofertilizer had not significant difference, but nitrogen use efficiency was higher in integrated biofertilizer and chemical treatment. Therefore, our survey suggests that combined use fertilizers without significant decline in yield quantity and quality were the best combination for maize crop production.