Preliminary investigation into the stimulation of plant growth promoting bacteria(PGPB)by soil amendment with a commercial humic acid

摘要

The stimulation of,or soil inoculation with plant growth promoting bacteria(PGPB)is recognized as a potential means of decreasing fertilizer inputs,the benefits of which are to decrease greenhouse gas emissions,nitrate run off and soil acidification.Rhizobium form symbiotic relationships with leguminous plants and supply nitrogenous compounds by fixing atmospheric nitrogen.In an incubation study,application of a commercial humic acid product was shown to increase the abundance of bacteria of the Proteobacteria phylum,specifically the Rhizobiales order and therein the Beijerinckiaceae,Bradyrhizobiaceae,Hyphomicrobium and Rhizobiaceae families.The results of this preliminary study may give some insight into the growth promoting effects of commercial humic acids.