The objective of this work was to identify indicators of resistance of aluminum toxicity in upland rice as well as lines with low susceptibility to this toxicity. Fifty one rice lines were evaluated in greenhouse, in nutrient solution, under two levels: 0 and 40 mg dm-3 of Al. Data of dry weight of roots and aerial parts, length of roots and plant height were obtained 21 days later. Also, the index of susceptibility to aluminum toxicity was calculated. The results showed significant correlation between all indicators with each other, except to those related to pH variability. Since root length susceptibility index (S Rcm) was calculated taking into consideration the root growth with and without stress and the pressure of aluminum stress under which the genotypes were evaluated, it can be considered a reliable tool for selection of cultivars/lines for resistance to aluminum toxicity. According to the distribution of lines in quarters delimited by root length higher than 47 cm and by SRcm lower than 0.92, the lines CNA4120, CNA4164, and CNA1383 were selected, which have roots well developed in the absence or presence of Al.
Oryza sativa; susceptibly index; roots; Al-sensitive and resistant lines
