Increasing species richness of arbuscular mycorrhizal fungi benefits some plants, but not others

Increasing species richness of arbuscular mycorrhizal fungi benefits some plants, but not others

As the global population continues to increase, we face the formidable challenges associated with global climate change and the pressing need to produce more food in an ecologically sustainable way. Most plants, including the world’s most important crops, form associations with a co-evolved group of soil-dwelling fungi (Glomeromycotina) known as arbuscular mycorrhizal (AM) fungi. These fungi are not only important for plant productivity and nutrient acquisition but are critical to many ecosystem processes. Thus, the management of the AM symbiosis is likely to be critical to sustainable land management into the future. Yet, the outcomes of this symbiosis for the host plant can depend on the plant and fungal identities, for example C4 plants are often observed to benefit more from AM fungi than C3. It can also depend on environmental context, such as soil phosphorus availability.

Controlled-environment experimentation using different AM fungal inoculants reveals that increasing AM fungal species richness in the soil can have substantial positive growth and nutritional outcomes for major C3 and C4 crop species. However, the results also highlight that some plants may derive little or no benefit from increasing AM fungal species richness. These findings suggest that although it may not be uniformly advantageous to all plants, promoting AM fungal diversity in the soil is likely to be a key contributor towards agricultural sustainability.