Seed inoculation with Growth Promoting Bacteria on the improvement of quantitative and qualitative traits of two corn cultivar

The effect of Plant Growth Promoting Rhizobacteria on quantitative and qualitative growth of two maize cultivars was investigated in a growth chamber experiment at agriculture college of the university of Guilan.   This research was arranged in a factorial experiment based on completely randomized design with three replications.  In this experiment, two factors were evaluated: cultivar (S.C. 704, 647) and 11 levels of seed inoculation with PGPB (seed uninoculation and without fertilizer, seed uninoculation and super phosphate triple fertilizer, Pseudomonas fluorescens strain 168 + Pseudomonas fluorescens strain 41+ Aztobacter chroococcum + Azospirillum sp., Pseudomonas fluorescens strain 168 + Aztobacter chroococcum + Azospirillum sp., Pseudomonas fluorescens strain 41 + Aztobacter chroococcum + Azospirillum sp., Azotobacter chroococcum + Azospirillum sp., Pseudomonas fluorescens strain 168 + Pseudomonas fluorescens strain 41, Pseudomonas fluorescens strain 41, Pseudomonas fluorescens strain 168, Azospirillum sp., Azotobacter chroococcum).   Seed inoculation with PGPB positively affected plant growth and P adsorption.  In all of investigated characteristics (except soil P), chemical fertilizer treatment was higher than co-inoculated treatments, but this difference was not significant.   Therefore it could be stated, these microorganisms need more time to fix and establishing themselves in soil.  The present finding showed that there is a linear relationship between plant phosphorus and its dry weight, therefore phosphate-solubilizing microorganisms can interact positively in promoting plant growth, nutrient uptake especially P of maize plants, root colonization percentage increasing and consequently, plant dry weight increasing.