QTL for agronomic traits in maize production

The utilization of molecular markers and genomics platforms offers unprecedented opportunities to discover, select, and clone the quantitative trait loci (QTL) that govern grain yield and other agronomic traits in maize. The dissection of the genetic basis of quantitative traits into their single components provides direct access to valuable genetic diversity for the morpho-physiological features that in maize regulate yield potential per se and the adaptative response to abiotic and biotic constraints. This in turn, enables us to utilize marker-assisted selection for enhancing maize performance and/or producing isogenic lines at target QTL to be cloned. This chapter summarizes the main result on the large number of studies that have described QTL for grain yield and other agronomic traits in maize. The availability of the sequence of the entire genome coupled with other genomics platforms will acelerate QTL discovery and cloning while facilitating a more effective exploitation of the allelic richness present at key QTL.