Marker-assisted selection: new tools and strategies

Abstract

The development of molecular genetics and associated technology has facilitated a quantum leap in our understanding of the underlying genetics of the traits sought through plant breeding. The usefulness of DNA markers for germplasm characterization, and of marker-assisted selection—the manipulation through DNA markers of genomic regions that are involved in the expression of traits of interest—for single-gene transfer, has been well demonstrated. However, when several genomic regions must be manipulated, marker-assisted selection has turned out to be less useful. The efficient and effective application of marker-assisted selection for polygenic trait improvement certainly needs new technology but, more importantly, it requires the development of innovative strategies that bypass the conceptual bottlenecks imposed by current approaches