The effect of different sources of fertilizer and low-irrigation on forage quality characteristics and yield of sorghum

This study was conducted as a factorial experiment in a randomized complete block design with three replications in the breeding center of buffalo in the northwest of Iran in 2020-2021 growing season. Experimental treatments included different irrigation conditions at three levels (irrigation after depleting of 40, 60, and 80% of available water) as the first factor and application of different fertilizer sources at five levels (chemical, biological, organic, nano fertilizer, and control) as the second factor. Crude protein, dry matter digestibility, water-soluble carbohydrates, and protein yield were improved under different fertilizer sources and different irrigation conditions compared to the control treatment. With delay in irrigation, dry matter, forage ash and relative feed value decreased, while water stress increased the amount of ADF and NDF. Also, the highest amount of dry matter, ash and the relative feed value were obtained in the nano fertilizer. Irrigation after depleting of 40% caused 24, 14, and 18% increase in dry weight of leaves, stems and forage yield, respectively, compared to 80% of available water. The highest dry weight of leaves, stems, and forage yield were obtained with 11738, 16764, and 27938 kg/ha in nano fertilizer, respectively. In conclusion, the results showed that nano-fertilizers and organic fertilizers were more effective in improving the quantitative and qualitative characteristics of fodder sorghum under water stress conditions compared to other fertilizer sources.