Plant growth has been doubled by adding soil microbes. Plants and soil microbes are constantly interacting in natural and agricultural environments and many examples of one-to-one interactions have been studied. However, the effect of mixed microbial populations on the growth and gene expression of plants still remained largely unknown.
This study evaluated the growth of leaves and roots of the model plant Arabidopsis thaliana in the presence or absence (i.e. in sterilized soil) of microbes extracted from compost soil. Surprisingly, leaf growth was doubled in the presence of microbes.
Chemical analyses and high-throughput analysis of gene expression within plant tissues and soil surrounding roots revealed that the added microorganisms facilitated iron acquisition by plants. Soil microbes also affected other plant processes, including acquisition of nitrogen, production of free radicals, and defense against diseases.
In conclusion, this study showed the main underlying processes occurring in plants during interactions with soil microbial populations and emphasized the important role of soil microbes for plant growth.
URL: http://www.frontiersin.org/Plant-Microbe_Interaction/10.3389/fpls.2013.00235/abstract