Inheritance of aluminum tolerance in wheat hybrid populations

Seedlings originated from hybrid populations, in F-2 generation, from 26 cr osses between tolerant wheat cultivars (BH-1146, IAC-227, IAC-24, IAC-60, C -3, IAC-5, IAC-ls and IAC-21) and sensitive cultivars (Anahuac 75, IAC-287, IAC-289, Siete Cerros and Veery "S") to aluminum toxicity and from 18 cros ses between tolerant cultivars (BH-1146, IAC-227, IAC-24, IAC-60, C-3, IAC- 5, IAC-21, C-17, IAC-74 and IAC-18) were evaluated for tolerance to 3 mg/L of Al3+, using nutrient solutions. It was considered tolerant the plant tha t was able to show root regrowth of the central primary root in the complet e nutrient solution after a treatment of 48 hours in solution containing 3 mg/L of Al3+. The evaluation of the seedlings from the F-2 populations orig inated from the tolerant and sensitive crosses showed that the tolerance to Al3+ toxicity was dominant and in 24 of the crosses the tolerant cultivars differed from the sensitive by one pair of genes. No difference was observ ed between the tolerant cultivars in relation to the pair of genes for the tolerance. Each one of these cultivars could be used as tolerance source in a crossing program, where this trait would be desired.