Rock eating fungi? The role of Mucoromycotina ‘fine root endophytes’ in silicate mineral weathering and plant nutrition

The project

We have recently shown that several arbuscular mycorrhizal plants also form endosymbioses with Mucoromycotina fine root endophytes (MFRE).

Because MFRE can grow in axenic culture they are likely facultative saprotrophs, a lifestyle similar to ectomycorrhizal fungi and very different to the obligate biotrophic arbuscular mycorrhizal fungi (AMF). However, much of the biology of MFRE, and their interactions with the environment, remain to be established. In particular, we do not know whether MFRE interact with soil minerals in a similar way as AMF, weathering silicates to extract nutrients that can then be ‘shared’ with their host plants.

This project will investigate this fundamental knowledge gap by a combination of in vitro experiments, elemental, scanning electron microscopy and isotope tracer analyses, together with transcriptomic and bioinformatic analyses to address the following objectives:

• Quantify the ability of MFRE to extract mineral nutrients from different silicates.
• Characterise MFRE-mineral interactions at the chemical and physical levels.
• Determine fungal gene expression patterns and metabolic responses to different minerals.
• Establish the bioavailability of the extracted mineral nutrients to host plants.

The relationship of Mucoromycotina fine root endophytes and plants

MFRE are widespread yet poorly understood and their partnerships with plants have remained ‘under-the-radar’ due to technical limitations in their detection and culture.

We have recently developed the essential techniques that allow us to overcome these limitations and have shown that MFRE form symbioses with diverse plants in both natural and agroecosystems.

This project will advance our knowledge of MFRE-mineral interactions and their role in plant nutrition and biogeochemical cycles.