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Native Cerrado plants are exposed to soils with low pH and high availability of Al. In this study, we measured the Al content in adult plants, and investigated the effects of various Al doses on germination and early development of Eugenia dysenterica plants. For germination tests, the seeds were soaked in Al solution and evaluated for twenty days in growth chambers. In a second experiment, young plants were cultivated in hydroponic systems with various Al concentrations to evaluate the morphological, anatomical and physiological characteristics of E. dysenterica. Anatomical changes and low germinative vigor were observed in seeds germinated in 600 and 800 μmol Al3+ L−1. In the hydroponic system, 200 μmol Al3+ L−1 stimulated root growth in young plants. The activity of antioxidant enzymes and the accumulation of phenolic compounds were greatest at the highest Al doses, preventing changes in gas exchange and chlorophyll a fluorescence. Starch grain accumulation was noted in plant cells exposed to 200 and 400 μmol Al3+ L−1. Adult E. dysenterica trees also accumulated Al in leaves, bark and seeds. These data suggest that E. dysenterica is tolerant to Al.

This study aimed to evaluate the effect of aluminum (Al) on root growth and root anatomical structure of Stenocalyx dysentericus seedlings. Newly emerged plants were grown in simple solution composed of 0.1 µM of CaCl 2 .2H 2 O and five Al concentrations of 0, 150, 300, 600, and 1200 μM for 37 days in a hydroponic system. Subsequently, the seedlings were evaluated for root growth, relative root elongation, and anatomical studies using bright-field and fluorescence microscopy techniques. The results showed tolerance by S. dysentericus, with more root relative elongation in treatments with 150, 300, and 600 μM of Al. The anatomical studies revealed the presence of Al in root tissue, through the morin reagent, mainly in the 1200 μM treatment, characterizing some internal detoxification mechanism. S. dysentericus demonstrated tolerance in the tests with Al, principally at lower doses. These results may be entirely linked to its wide distribution in the cerrado domain, demonstrating to be a species adapted to soils with higher Al concentration. S. dysentericus, when subjected to treatment with Al, showed a stimulating effect on root growth; for this species, low concentrations of Al may be essential for better root growth.