Requirements for success in marker-assisted breeding for drought-prone environments

Abstract

The challenge that commercial breeders have in improving the yield of crops in drought-prone environments is to produce cultivars that capture more of the water supply for use in transpiration; exchange transpired water for CO 2 more effectively in producing biomass; and convert more of the biomass into grain. Many traits affect these requirements, and assume greater or lesser importance depending on the severity and timing of a drought. Although hundreds of QTLs have been found that are associated with improved yield during drought, few have been converted into markers useful to breeders owing to the difficulty of understanding the phenotype in realistic environments. The few markers that are in use target disease resistance and morphological or ecophysiological traits known to affect the water economy of a crop. Faster progress in developing markers useful to breeders will come with the evidently increasing interaction between breeding programs and marker laboratories © 2007 Springer.