The objectives of this work were to compare Al tolerance among 17 species of tropical leguminous plants and to evaluate the most appropriate plant characteristic and Al concentration in nutrient solution for tolerance assessment. In addition, three soybean cultivars were included for comparison purposes. There was a great difference among the 17 plant materials tested, when compared by relative root elongation and critical Al activity to reduce 50% of root net elongation. Based on these parameters and on the comparison of two tropical maize genotypes differing in Al tolerance, the following classification was established: highly tolerant, for Mucuna nivea, M. deeringiana, M. aterrima Vigna unguiculata cv. BR 17 and Lablab purpureus cv. Rongai; tolerant for... |