|Rodriguez Milla, Manuel - UNIV OF MISSOURI|
|Miftahudin, - UNIV OF MISSOURI|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 1, 2003
Publication Date: May 27, 2003
Citation: Rodriguez Milla, M.A., Miftahudin, Gustafson, J.P. 2003. Aluminum tolerance in cereals. In: Proceedings of "In the Wake of the Double Helix: From the Green Revolution to the Gene Revolution" symposium, May 27-31, 2003, Bologna, Italy. p. 39. Technical Abstract: Aluminum is present in acid soils, which are known to limit plant growth on approximately 46% (about 2.5 billion hectares) of all arable land. Screening a collection of wheats in hydroponic solutions containing aluminum showed that no progress has been made in the last 50 years in increasing wheat tolerance to aluminum. The impact of this is that there are probably no more genes available in the existing wheat primary gene pool for increasing wheat's tolerance to aluminum and, if increased tolerance is needed, we will have to search related species gene pools. The present study was designed to map the location of the gene(s) controlling aluminum tolerance in wheat and rye, and establish molecular markers flanking the gene(s). The polymorphism rates in wheat for the markers used were extremely low, as confirmed by the physical mapping of AFLPs, making any map-based cloning very difficult, therefore we initiated a mapping project in rye. Genetics of aluminum tolerance in rye was characterized by identifying Alt3 locus controlling Al tolerance in a rye. Five AFLP markers and two sequence tagged site (STS) markers were tightly linked to the Al gene. The STS markers, developed from rice were used to construct a high resolution map of the Alt3 gene region. The results showed that the Alt3 gene was located in a 0.1 cM region between an AFLP and RFLP marker. Primers developed from one of the markers amplified rye genomic DNA which was used as a probe for a root gene expression time-course study under Al stress. The results showed that the gene was expressed only under Al stress on Al-tolerant roots, but not on Al-sensitive roots.