Arbuscular Mycorrhizal Fungi Under Intercrop, Regenerative, and Conventional Agriculture Systems

Arbuscular mycorrhizal fungi (AMF) increase in diversity and abundance in agricultural systems that emphasize soil health practices, including regenerative agriculture and intercropping. Regenerative agriculture in principle includes any practice that increases biodiversity and living roots and integrates livestock while reducing tillage, bare soil, and agrichemical inputs. Intercropping increases biodiversity in an annual system and reduces disease prevalence and weeds while improving soil conditions and yielding more than the equivalent monocrop. These principles and practices simultaneously support AMF proliferation in soils and in turn AMF provide multiple benefits to crops. AMF colonize roots, trading photosynthates for nutrients acquired beyond the reach of the plant root system. While colonizing roots, they trigger innate plant immunity and confer resistance to some insect, fungal, and bacterial pests. Colonized plants hold more water and thus are more resistant to drought. In soils with ample AMF propagules, multiple plants are likely to become connected to their neighbors by a common mycorrhizal network (CMN). Plants connected by a CMN are likely to share beneficial microbes, resistance to disease, and resources. A better understanding of crop root traits and AMF is important to building a wholistic picture of ecological interactions that can be leveraged to maintain agricultural production in intercropped, regenerative, and conventional systems.