Symbiosis with Penicillium sp. D7 Rewires Molecular Modules to Boost Plant Growth and As(III) Stress Tolerance

These tight mutual relationships can provide physiological benefits to the interacting organisms, including the improvement of nutrient assimilation or enhanced stress tolerance. The root-colonizing fungus Penicillium sp. strain D7 has been isolated from roots of Digitalis thapsi L. that were grown on the As-rich tailings of the Mónica mine in Bustaviejo, Spain.

Here, we report the promotion of plant biomass production and stress tolerance of Arabidopsis thaliana L. plants inoculated with D7. The comparative analysis of the effect of mock- and D7-inoclulated wild-type Arabidopsis plants (Col-0) in the absence and presence of arsenite As(III) stress conditions (15 µM NaAsO2). Our data provide evidence for a profound effect of D7 on As(III) detoxification through the activation of a regulatory network that includes several plant hormones.