Genetic control of aluminum tolerance in mutant lines of the wheat cultivar Anahuac

The behavior of 17 gamma irradiation mutant lines derived from the aluminum sensitive wheat cultivar `Anahuac' was compared with two sensitive and three tolerant cultivars in nutritent solutions containing seven Al<sup>3+</sup> concentrations (0; 0.5; 1; 2; 4; 6 and10 mg/liter), at a temperature of 25 <sup>°</sup>C and 4.0 pH. Tolerance was measured by the continued growth of the primary roots in a solution without aluminum after 48 hours in a solution containing a known concentration of aluminum. 14 mutant lines were as tolerant to the presence of 10 mg/liter of Al<sup>3+</sup> in the treatment solutions as were the tolerant `BH-1146', `IAC-60' and `IAC-24' cultivars. Two mutant lines were tolerant and one was sensitive to the presence of 1 mg/liter of Al³⁺, while the cultivars `Siete Cerros' and `Anahuac' were sensitive to 1 and 0.5 mg/liter Al³⁺ in the solutions, respectively. F₂ seedlings, obtained from cross among one sensitive and twelve tolerant mutant lines to the sensitive cultivars (`Siete Cerros' or `Anahuac') and the tolerant cultivars (`BH-1146' or `IAC-24') were assessed for tolerance to 2 mg/liter Al³⁺ in nutritient solutions. The twelve tolerant mutant lines and the tolerant `IAC-60' and `IAC-24' cultivars differed from the sensitive `Siete Cerros' or `Anahuac' cultivars by one pair of dominant alleles. The results indicated that tolerance in the induced mutants was due to a single pair of dominant alleles and that these alleles expressed the same tolerance as `BH-1146' and `IAC-24' cultivars. This revised version was published online in July 2006 with corrections to the Cover Date.