بررسي اثر كود نيتروژن بر كيفيت سيلوي سه رقم سورگوم علوفه اي

The effects of different levels of nitrogen on silage quality of three sorghum cultivars

An expriment was conducted to evaluate the effects of different levels of N on forage yield and silage quality of three sorghum cultivars. The sorghum cultivars Viz: Speed feed, Jumbo, and Syahzan, a native strain, were cultivated in four levels of N fertilizer (0, 50, 75, and 100 Kg/ha). Their yield and quality were compared in a Completely randomized block design with split - poll layout and three replications. Seeds were hand sown in a density of 20 plant/m2 in late spring 1997. The CP, CF, Ash and pH content of the harvested plants were measured by the appropriate procedures.Lahoratory silages were made from the harvested and chopped plants wih DM content of 18.9 to 22.2 in a polyethylen 20 liters containers for 6 weeks in ambiant temperature. Nitrogen application of 100 Kg/ha produced the highest forage dry matter as well as silage production in Syahzan cultivar. Jambo cultivar significantly produced the highest forage and silage dry matter than the other cultivars (14 and 1.3.5 tons DM/ha), respectively. There was a significant difference (p<0.05) among cultivars for protein component, crude fiber percentage and ash content. The native strain (Syahzan) and Speed feed produced highest protein percentages and protein yield as well as the highest crude fiber, respectively. Ensilage caused an incease in protein, crud fiber and ash content for all cultivars.