Influence of aluminum on root growth and of anatomy Stenocalyx dysentericus (DC.) O. Berg

Abstract

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 CaCl₂.2H₂O 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.

Keywords: Cerrado, acidic soils, plant toxicity, tolerance