Twelve bread wheat (Triticum aestivum L.), one durum wheat (Triticum durum L.) and one triticale (Triticosecale sp) genotypes were studied in nutrient solutions with a high salt concentration in experiment 1 and a weak salt concentration in experiment 2, for aluminum tolerance at six levels: 0, 2, 4, 6, 8 and 10 mg L-1, under temperature 25 ± 1ºC and pH 4,0. Four replications were used per experiment. Aluminum tolerance was evaluated by measuring root growth in an aluminum-free complete nutrient solution after a treatment of 48 hours in an aluminum solution associated with a particular salt concentration, according to the experiment. The bread wheats IAC-289, IAC-350 and IAC-370, the durum wheat IAC-1003 and the triticale IAC-5 genotypes were the most sensitive for increasing levels of Al3+in treatment nutrient solutions. Thus, they would be indicated only for cultivation in limed soils. The bread wheat IAC-24 and IAC-378 genotypes and the check cultivar BH-1146 were the most tolerant to Al3+ toxicity, being able to show good performance in acidic soils and/or to be used as genetic sources for tolerance in future crosses. Under constant temperature 25 ± 1ºC and pH 4,0 aluminum toxicity results in inhibition of root growth wich was dependent on the increase of the aluminum concentration or on the reduction of the salt concentration of the nutrient solution for all evaluated genotypes.
Triticum aestivum L.; Triticum durum L.; Triticosecale sp; root growth; relative tolerance index
