Interaction between Crop and Mycorrhizal Fungi Specie Affects Root Colonization.

In highly weathered tropical soils phosphorus is not widely available, becoming a beneficial strategy the symbiotic association between plant and arbuscular mycorrhizal fungi (AMF), which induce the increase of root soil exploration by hyphae for nutrient and water acquisition. In general, host plant interacts strongly with AMF species, affecting mycorrhizal colonization. The objective of this work was to evaluate the mycorrhizal colonization rate in different host plants. For this, a greenhouse experiment was conducted using six plant species: i) Triticum aestivum; ii) Glycine max; iii) Crotalaria juncea; iv) Zea mays; v) Sorghum bicolor; vi) Brachiaria brizantha separately inoculated with three AMF species: i) Rhizophagus clarus; ii) Dentiscutata heterogama and iii) Acalouspora colombiana. The root sampling was performed 20 days after plant emergency and mycorrhizal colonization was evaluated. Interaction between the AMF and crops species was observed, occurring in a specific colonization of plants. When AMF was not inoculated, Brachiaria brizantha was more efficiently colonized by the native AFM species, compared to other crops. High rates of mycorrhizal colonization were also observed in the Brachiaria brizantha when R. clarus and D. heterogama were inoculated. Possibly, these fungi species were native in the ecosystem, and the spore inoculation favored their colonization. In contrast, when A. colombiana was inoculated, high colonization rates were observed in five crops, except to Brachiaria brizantha. It may indicate that A. colombiana was not present in the ecosystem and its inoculation was more influenced by the host plant.