Acid soils containing high levels of aluminum (Al) are known to severely li
mit plant growth on over 1.6 billion hectares worldwide. In the United Stat
es, a gradual decline in the pH of many soils both in the Great Plains as w
ell as the Southeast, has caused many soils to become high in levels of fre
e Al. This worldwide condition encouraged the analysis of wheat (Triticum a
estivum L. em Thell.), triticale (X Triticosecale Wittmack), and rye ( Seca
le cereale L.) germplasm from one of the major acid soil regions of the wor
ld (Brazil) in order to evaluate and compare the genetic potential of Al ge
nes for cereal improvement. The objectives were to compare Al-tolerance lev
els in wheats, triticales, and ryes by measuring root elongation responses
in Al-containing hydroponic nutrient solutions. Root elongation was impaire
d for all species grown in 1 mg/L concentrations of Al. Rye had the longest
root regrowth and Al-sensitive wheats had the shortest root regrowth. The
triticales containing a 2D(2R) substitution developed in the mid-1970s had
the poorest root regrowth of all triticale types. The newly developed advan
ced triticale lines (AABBRR) yet to be released for commercial production s
howed the highest degree of Al tolerance of all the triticale types and app
roached or exceeded the levels observed in rye. This indicated that progres
s is being made in improving Al-tolerance of triticale in Brazil. Of all th
e old and new wheat varieties showing the highest degree of Al-tolerance, n
one of them were better than 'BH 1146' a variety that is at least 50 years
old. This indicated that over the past 50 years, although Brazilian wheat b
reeders have made yield improvements in wheat production, they have not imp
roved Al-tolerance. Rye showed a higher degree of Al-tolerance than the oth
er cereals when tested in 1 mg/L of Al, but as expected, some variation was
noted.