Effects of phosphate solubilizing microorganisms and phosphorus chemical fertilizer on forage and grain quality of barely (Hordeum vulgare L.)

The effect of seed inoculation by phosphate solubilizing microorganisms and different levels of phosphorus chemical fertilizer on forage and grain quality of barley (Karoon x Kavir cultivar) was studied in Experimental Farm of College of Agronomy and Animal Sciences، University of Tehran during 2006-2007 growing season. The experimental treatments were arranged in split plot factorial based on a complete randomized block design with four replications. Three phosphorus fertilizer levels of 0 (control)، 30 and 60 kg/ha were allocated to the main plots and three levels of Phosphate solubilizing bacteria of 0 (control)، Pseudomonas putida accessions number 9 and 41 along with two levels of Mycorrhiza: with and without Mycorrhiza (control) were assigned to the subplots in a factorial combination. Applications of sole bacteria (accession 41) significantly decreased NDF (57. 4%) in barley forage. The maximum grain protein (11. 37%) was obtained with application of sole Mycorrhiza. The same treatment also could increase ASH to an acceptable level (8. 05%). NDF significantly (p<0. 05) decreased and WSC increased as application of chemical phosphorous fertilizer increased. Sole and co-application of Mycorrhiza and bacteria had a significantly positive influence on increasing the percentage of grain protein and ASH and decreasing the NDF value. The application of theses inoculants could be considered as an appropriate substitute for chemical phosphorous fertilizer in organic and sustainable agricultural systems.