[No Title Available]

Abstract

The degree of tolerance to aluminum of the corn variety "Dentado Composto" was related to of a tolerant variety "Cateto Colombia 96/71", and a susceptible one "Cateto Al 20268", by comparing the growth of their root systems in aqueous media with and without calcium and aluminum. The experimental design used was a 3 x 2 factorial in random blocks the following parameters were studied: depth of the main root in the solution, number and tota1lenght of seminal roots, pH variations in the solution and morphological aspects of the root system during 10 days of experiment. "Dentado Composto" showed intennediate tolerance compared to "Cateto Colombia 96/71" and "Cateto AI 2026S", which demonstrated their respective tolerance and susceptibility. Further reasearch should be conducted with "Dentado Composto" in relation to its aluminum tolerance, using lower aluminum and/or higher calcium concentrations. In this case, toxicity symptoms could be less evident and the variety would be considered as viable in a breeding program aiming at the development of aluminum tolerant varieties to be used in areas where mechanical and economical aspects make it unfeasible to lime the soil in order to overcome production limitations imposed by aluminum toxicity.