RESPONSE OF STYLOSANTHES-GUIANENSIS TO ENDOMYCORRHIZAL FUNGI INOCULATION AS AFFECTED BY LIME AND PHOSPHORUS APPLICATIONS .2. NUTRIENT-UPTAKE

The nutrient concentration in the shoots of Stylosanthes guianensis (Aubl.) Sw. cultivated in a sterilized acid and dystrophic soil (Quartzipsament) amended with 4 levels of lime (0; 0.27; 0.63 and 1.10 meq Ca2+/100 g soil, as Ca(OH)2), 2 levels of P (0 and 20 mg P kg-1 soil, as KH2PO4) and not-inoculated or inoculated with 3 vesicular-arbuscular (VA) mycorrhizal fungi was evaluated under greenhouse conditions. The effectiveness of the different fungal species in increasing the nutrient concentration in the shoots varied with the different edaphic conditions. In general, mycorrhiza formation was associated with increases in the concentrations of most of the nutrients analyzed. Under the experimental conditions, the increments in nutrient concentration were higher overall in plants inoculated with Acaulospora scrobiculata. Inoculation of S. guianensis with VA mycorrhizal fungi was also associated with alterations in the ratios of nutrients in the shoots, which might be important in understanding and explaining the tolerance of mycorrhizal plants to nutritional stresses such as Al and Mn toxicity.