Ten wheat cultivars were studied with relation to iron toxicity using five different levels of this element (0.56; 5.0; 10.0; 20.0 and 40.0 mg/l) in nutrient solution with and without aeration, under constant temperature (27ºC ± 1ºC) and pH 4.0. The tolerance of the plants was measured taking into account the mean of the primary root length and the total leaf dry weight of 20 seedlings per treatment solution. The presence of high levels of iron (10.0; 20.0 and 40.0 mg/l) in the solution, with or without aeration, was harmfull to all wheat cultivars under study, but there were differences in growth among the plants, depending on the degree of tolerance of each cultivar. The cultivars Siete Cerros, Alondra 4546 and CNT-8 were tolerant to the increating levels of iron in the aerated and non-aerated nutrient solution and the cultivars IRN-204-63, IAC-5, IAC-18, IAC-17, IAC-13, BH-1146 and IAC-24 were susceptible. The phosphorus, potassium, calcium, magnesium and manganese concentrations decreased in the top part of the plants as the levels of iron increased in the nutrient solution for the cultivars BH-1146 and Siete Cerros. The iron concentration in the leaves of BH-1146 and Siete Cerros increased as the levels of iron increased in the nutrient solution. The aeration in the nutrient solution caused an increase in the leaf iron concentration.
iron tolerance; toxicity; sensitivity; wheat; nutrient solution; iron toxicity; tolerance of wheat to iron toxicity; nutrient solution; wheat cultivars tolerant to iron toxicity; wheat cultivars sensitive to iron toxicity