association and linkage analysis of aluminum tolerance genes in maize协会,在玉米耐铝基因的连锁分析.pdf

Association and Linkage Analysis of Aluminum Tolerance Genes in Maize Allison M. Krill1,2, Matias Kirst3,4, Leon V. Kochian1,5, Edward S. Buckler1,2,3, Owen A. Hoekenga1,2* 1 United States Department of Agriculture-Agricultural Research Service, Robert W. Holley Center for Agriculture and Health, Ithaca, New York, United States of America, 2 Cornell University, Department of Plant Breeding and Genetics, Ithaca, New York, United States of America, 3 Institute for Genomic Diversity, Cornell University, Ithaca, New York, United States of America, 4 University of Florida, School of Forest Resources and Conservation, Gainesville, Florida, United States of America, 5 Cornell University, Department of Plant Biology, Ithaca, New York, United States of America Abstract Background: Aluminum (Al) toxicity is a major worldwide constraint to crop productivity on acidic soils. Al becomes soluble at low pH, inhibiting root growth and severely reducing yields. Maize is an important staple food and commodity crop in acidic soil regions, especially in South America and Africa where these soils are very common. Al exclusion and intracellular tolerance have been suggested as two important mechanisms for Al tolerance in maize, but little is known about the underlying genetics. Methodology: An association panel of 282 diverse maize inbred lines and three F2 linkage populations with approximately 200 individuals each were used to study genetic variation in this complex trait. Al tolerance was measured as net root growth in nutrient solution under Al stress, which exhibited a wide range of variation between lines. Comparative and physiological genomics-based approaches were used to select 21 candidate genes for evaluation by association analysis. Conclusions: Six candidate genes had significant results from association analysis, but only fou