Mapping and validation of the quantitative trait loci for leaf stay-green-associated parameters in maize

Functional stay-green is generally regarded as a desirable trait of varieties in major crops including maize. In this study, we used an F-3:4 recombinant inbred line population with 165 lines from a cross between a stay-green inbred line (Zheng58) and a model inbred line (B73) using 211 polymorphic simple sequence repeat markers to map quantitative trait loci for three stay-green-associated parameters, chlorophyll content, photosystem II photochemical efficiency and stay-green area, at maturity stage, detected a total of 23 quantitative trait loci (QTL) on nine chromosomes. Single QTL explained 3.7-13.5% of the phenotypic variance. Additionally, we validated some important stay-green QTL using a heterogeneous inbred family approach and found that the stay-green-associated parameters were significantly correlated with the plant yield. This study may contribute to a better insight into the regulatory mechanism behind leaf stay-green in maize and a novel development of elite maize varieties with delayed leaf senescence through molecular marker-assisted selection.