The effects of arbuscular mycorrhizal fungi (AMF) were evaluated on the growth and mineral composition of Mentha arvensis L., grown under different phosphorus levels. The experiment was carried out in a greenhouse, in a factorial scheme 5x4, with five microbiological treatments (control without AMF, Glomus clarum, Glomus etunicatum, Gigaspora margarita and Acaulospora scrobiculata) and four P levels (0; 50; 100 and 200 mg kg-1). A randomized block design was used, with four replications. The plants were harvested at flowering, 65 days after planting. When no phosphorus was added, Gigaspora margarita and Glomus clarum led to a higher percentage of mycorrhizal colonization in roots and increased 334 and 330% the dry matter production of shoots, 143 and 123% the N content, 224 and 124% the P content, 139 and 142% the K content, respectively. The AMF inoculation did not influence Ca, Mg, S, Fe and Zn contents. Dry matter production was higher under P doses from 122 to 165 mg kg-1 of soil. In such doses, Mn content was lower when the plants were inoculated with Glomus clarum, Gigaspora margarita and Glomus etunicatum. The mycorrhizal dependence of the mint varied with microbiological treatments and P levels, being higher with Glomus clarum and Gigaspora margarita, under no phosphorus addition.
Mentha arvensis; plant nutrition; mycorrhiza; phosphorus; aromatic and medicinal plants
