Linking microarray data to QTLs highlights new genes related to Al tolerance in maize.

The presence of aluminum (Al) is one of the main factors limiting crop yield in Brazil and worldwide. Plant responses to Al are complex, and the use of techniques such as microarrays can facilitate their comprehension. In a previous work, we evaluated the transcriptome of two maize lines, Cat100-6 and S1587-17, after growing the plants for 1 or 3 days in acid soil (pH 4.1) or alkaline soil with Ca(OH)₂ (pH 5.5), and we identified genes that likely contribute to Al tolerance. The mapping of these genes to the chromosomes allowed the identification of the genes that are localized in maize QTLs previously reported in the literature as associated with the tolerant phenotype. We were able to map genes encoding proteins possibly involved with acid soil tolerance, such as the ones encoding an RNA binding protein, a protease inhibitor, replication factors, xyloglucan endotransglycosylase and cyclins, inside QTLs known to be important for the Al-tolerant phenotype.