Assessment the Effect of Organic Fertilizers, Biofertilizers and Chemical

Quality is one of the most important factors on forage production. In order to evaluate the effect of organic fertilizers, biofertilizers and chemical fertilizers on forage quality of Sorghum, a field experiment was conducted in Farm Research Station, Faculty of Agriculture, Ferdowsi University of Mashhad during the year 2008. Treatments were 1- seed inoculation with the combination of Azotobacter and Azospirillum 2- Compost (15 t/h) 3- Vermicompost (10 t/h). 4-seed inoculation with Azotobacter and Azospirillum and compost (15t/h) 5- seed inoculation with Azotobacter and Azospirillum and Vermicompost(10t/h) 6- seed inoculation with Pseudomonas flurescence 7- seed inoculation with Pseudomonas flurescence and Azotobacter and Azospirillum combination 8- seed inoculation with Pseudomonas flurescence and compost(15t/h) 9- chemical fertilizer (80 kg/h urea fertilizer and 50 kg/h phosphate fertilizer) 10- control. A randomized complete block design with 10 treatments and 3 replications was used. The studied quality factors were Dry Matter Digestibility (DMD), Organic Matter Digestibility (OMD), D-Value, Ash percentage and Crude Protein (CP). Harvesting was performed in 2 cuts. Results of the experiment indicated that DMD, AMD, D-Value and Ash percentage were not affected by the treatments. The highest and the lowest amount of DMD obtained in combined treatment of compost and pseudomonas and chemical fertilizers in two cuts, respectively. Protein content of forage was significantly affected by the treatments. Combined treatment of Azotobacter and vermicompost had the highest amount of crude protein (115.78 g/kg) and pseudomonas treatment had the lowest (92.65 g/kg) on first cut. On second cut, Azotobacter and vermicompost treatment and control treatment had the highest (117.14 g/kg) and he lowest (85.63 g/kg) crude protein content, respectively. Amount of CP in chemical fertilizers treatment was highly decreased on second cut. In general, results of this experiment showed that organic fertilizers,biofertilizers and chemical fertilizers has a little effect on DMD, OMD, D-Value and Ash percentage, but has a great effect on Crude Protein content of forage and can increase the forage quality in this way.