Introduction
Forage production has recently reduced in some arid and semi-arid countries due to intensive grazing and consecutive dryness. Increasing scarcity of water irrigation, particularly in arid and semi-arid climates where agricultural systems are dependent upon supplemental irrigation, is becoming the most important problem for producing forage.
The bio fertilizers can serve a potential tool for sustaining crop production without destruction of the soil and environment. Therefore, integrated application of bio fertilizer and chemical fertilizer seems to be a sustainable approach in agricultural systems. The plant growth promoting bacteria plays an important role in the crop growth and development through secretion of growth promoting metabolites and nutrient supply. These species increase nitrogen fixation and release plant growth promoting substances and hormones and improve nutrient and water uptake.
Sorghum is becoming an increasingly important forage crop in many arid and semi-arid regions of the world especially in Iran because of its advantages over corn in warm and dry climates. The objective of this study was to evaluate the effects of different fertilizer patterns and irrigation intervals on the quantity and quality of the sorghum forage.
Materials and Methods
The experiment was conducted as split plot design based on randomized complete block design (RCBD) with 15 treatments and three replications at the faculty of Agriculture, University of Maragheh during 2016. The treatments included three different irrigation regimes (irrigation after 60, 100 and 140 mm evaporation from class A evaporation pan) and five different fertilization patterns (100% chemical fertilizer, bio fertilizer, bio fertilizer+ 75% chemical fertilizer, bio fertilizer+ 50% chemical fertilizer and bio fertilizer+ 25% chemical fertilizer). In the current research, quantity and quality properties including neutral detergent fiber (NDF), acid detergent fiber (ADF), crude protein (CP)