effects of different plant growth promoting rhizobacteria (pgpr) application methods on forage production in sorghum (sorghum bicolor var. speed feed)

to evaluate the effect of different application methods of different strains of pgpr on sorghum forage production, a field experiment was conducted in research farm of college of agriculture of university of tehran in karaj during 2009. the treatments were arranged factorially and the data was analyzed based on a complete block design with three replications. the treatments comprised of three pseudomonas putida (strains:34, 53 and 100) and three pseudomonas fluorescence (strains: 82, 162 and 169) which were applied either by seed inoculation, foliar spray application or integrated application (inoculation and foliar spray). the results showed that the integrated application over yielded the forage production over other application methods for all different bacteria strains. the results supported the synergistic effects of integrated application method on forage yield as well as leaf area, leaf dry weight and stem dry weight. the highest forage yield was obtained by bacteria strains of 87, 100 and 162 in integrated application method.