عنوان مقاله [English]
The effect of co-inoculation with plant growth promoting Rhizobacteria (PGPR) and Rhizobium on yield and yield components of red bean, Phaseolus vulgaris L. cultivars was investigated in agricultural research station of Islamic Azad university of Shahrekord during 2006-2007. The experiment was done in split plot in the basis of randomized complete block design in three replications. Six strains of Rhizobium and a nitrogen fertilizer treatment were considered as the main factor and three red bean cultivars (Akhtar, Gholi, and Sayyad) were as the sub factors. PGPR strains of Pseudomonas fluorescens P-93 and Azospirillum lipoferum S-21 as well as two highly effective Rhizobium strains were used in this study. Common bean seeds of three cultivars were inoculated with Rhizobium singly or in combination with PGPR to evaluate their effect on growth characters. Results indicateed that soil beneficial bacteria can positively affect symbiotic performance of Rhizobia. A significant variation of plant growth in response to inoculation with Rhizobium strains was observed. Treatment with PGPR significantly increased number of pods per plant, number of seeds per pod, weight of seeds per plant, weight of pods per plant, total dry matter in R6 stage as well as seed yield and protein content. Co-inoculation with Rhizobium and PGPR caused a significant increase in the yield and yield components. The results showed that all treatments of bacteria increased yield. However, strains Rb-136 with Pseudomonas fluorescens P-93 caused the highest seed yield, number of pods per plant, weight of 100 seed, number of seeds per pod and seed protein yield.