Genetic parameters and QTL for tolerance to flooded soils in maize
Sérgio Delmar dos Anjos e Silva, Maria Jane Cruz de Melo Sereno, Cláudia Fernanda Lemons e Silva, Antonio Costa de Oliveira, and José Fernandes Barbosa Neto
Flooding tolerance is important for maize in southern Brazil. Polypeptides involved in glycolysis and fermentation are generally tolerance-related. Objective of this work was to associate markers for tolerance to flooding in maize. One hundred and seventeen F3 families were phenotyped for shoot (SDM) and root (RDM) dry matter and 74 were selectively genotyped with 44 microsatellite markers. A single marker analysis was performed to detect QTL. Analysis of variance indicated the presence of significant genetic variability for both traits. Three markers were associated to SDM and two to RDM. For SDM the loci involved were glutamine synthetase (chromosome 5, R2=0.16), zein (chromosome 4, R2=0.15), and triosephosphate isomerase (chromosome 3, R2=0.14). For RDM, zein (chromosome 4, R2=0.11) and triosephosphate isomerase (chromosome 3, R2=0.11) were associated. Multiple loci analysis indicated R2=0.32 for SDM and R2=0.19 for RDM, indicating that a fraction of the genetic variation present in F2 was explained by the analyzed markers.