This study examined the effects of different biofertilizers and manure on the absorption and absorption efficiency of macronutrients by wheat in Alborz Province, Iran. The experimental design was factorial in the form of a randomized complete block design with three replications. The four factors of the experiment were Azospirillum (with 600 g/ha and without), mycorrhiza (with 1 kg/ha and without), Streptomyces (with 0.5 kg/ha and without) and manure (with 30 t/ha and without). To measure N, P and K, plants were harvested one time when grains were at dough stage and another time at plant maturity, oven dried, grinded and analyzed. Azospirillum, mycorrhiza and manure had a significant effect (p ≤ 0.01) on most of the measured traits, but the effect of Streptomyces was not significant. The two-fold and three-fold interactions significantly affected the absorption and absorption efficiency of the three macronutrients. In most cases, four-fold interactions yielded the highest values. Overall, the experimental results indicate that biofertilizers and manure can naturally meet most of the plant's nutritional requirements, improve the efficiency of nutrient absorption and replace part of chemical fertilizers in sustainable agricultural production systems.
Keywords: Azospirillum; Macroelements; Manure; Mycorrhiza; Streptomyces.