The nitrogen flux from fungus to the host was found to be positively regulated by the carbon flux from the host tothe fungus, indicating a tight nutrient regulation between the symbiotic partners [14]. Interestingly, when tested inbinary systems, different AM fungi were found to differ in their capacity to transfer nitrogen to the plant, f.ex. Glomus intraradices transferring more thanGlomus hoi[12]. Moreover, microbiota studies of fungal communities associated withplant roots found that in natural environments, plants are colonized by several lineages of the Glomeromycota order. It remains to be determined if this diverse AM communityhasrelevance fornitrogennutritioninplants.