|Baier, A - CNPT-EMBRAPA, BRAZIL|
|Somers, D - UNIV OF MISSOURI|
Submitted to: Low Soil pH Meeting
Publication Type: Abstract Only
Publication Acceptance Date: August 10, 1998
Publication Date: N/A
Technical Abstract: Acid soils containing high levels of aluminum (Al) are well known to severly limit plant growth on over 250 million hectares in Brazil. The analysis of wheat (Triticum aestivum L. em Thell.), triticale (X Triticosecale Wittmack), and rye (Secale cereale L.) germplasm from Brazil was done to evaluate and compare the genetic potential of Al genes for varietial improvement. The objectives were to compare the Al-tolerance levels in wheats, triticales, and ryes by measuring root elongation repsonses in Al-containing hydroponic nutrient solutions. Rye had the longest root regrowth and Al-sensitive wheats had the shortest root regrowth. The previously licenses triticale varieties from the mid-1970s had the poorest root regrowth of all triticales, while those licensed in the late 1980s showed root regrowth similar to that of wheat. The newly developed advanced triticale lines yet to be released for commercial production showed the highest degree of tolerance of all the triticales, thus indicating that not only has progress been made in improving triticale yield potential in Brazil, but that progress has been made in improving Al-tolerance. However, of all the wheat varieties showing the highest degree of Al-tolerance, none of them was significantly better than BH1146 - a variety that is over 50 years old. This indicates that Brazilian wheat breeders have improved yield potential in wheat, but not Al-tolerance. In contrast, rye showed the highest degree of Al- tolerance; but variation was noted for each of the different growth parameters. The implications of these results in relation to wheat and triticale breeding and the expression of rye in a wheat background are discussed.