Plant, Animal & Microbe Genomes X Conference

January 12-16, 2002
Town & Country Convention Center
San Diego, CA

Workshop: Abiotic Stress
            

MOLECULAR, GENETIC, AND PHYSIOLOGICAL INVESTIGATIONS OF PLANT ALUMINUM TOLERANCE MECHANISMS

¹ U.S. Plant, Soil and Nutrition Laboratory, USDA-ARS, Cornell University, Ithaca, NY 14853

² Plant Science Research Unit, USDA-ARS, 411 Borlaug Hall, University of Minnesota, St. Paul, MN 55108

³ Institute for Plant Genomics and Biotechnology, and Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843

Acid soils comprise up to 50% of the world's potentially arable lands, and are a major limitation to worldwide crop production. On these acid soils, aluminum (Al) toxicity is the primary factor reducing crop yields, primarily via Al inhibition of root growth. Significant inter- and intraspecific variation in plant Al tolerance exists; this variation has been exploited for many years by plant breeders to generate crops with increased Al tolerance. Additionally, over the past 10 years, there has been considerable basic research using Al tolerant and sensitive genotypes to begin to elucidate the molecular, genetic, and physiological basis for Al tolerance. Fundamental research from a number of labs has identified an important mechanism of crop Al tolerance based on Al activated release of Al detoxifying organic acids from the root tip, which is the primary site of Al toxicity. In this talk, research findings from our laboratories based on an interdisciplinary approach integrating molecular, genomic, and physiological investigations of plant Al tolerance will be presented. These findings are helping us to better understand Al tolerance mechanisms in plants and ultimately, to isolate major Al tolerance genes that can then be used to generate crops better suited for agricultural production on acid soils.