Marker assisted selection in crop plants

Abstract

Genetic mapping of major genes and quantitative traits loci (QTLs) for many important agricultural traits is increasing the integration of biotechnology with the conventional breeding process. Exploitation of the information derived from the map position of traits with agronomical importance and of the linked molecular markers, can be achieved through marker assisted selection (MAS) of the traits during the breeding process. However, empirical applications of this procedure have shown that the success of MAS depends upon several factors, including the genetic base of the trait, the degree of the association between the molecular marker and the target gene, the number of individuals that can be analyzed and the genetic background in which the target gene has to be transferred. MAS for simply inherited traits is gaining increasing importance in breeding programs, allowing an acceleration of the breeding process. Traits related to disease resistance to pathogens and to the quality of some crop products are offering some important examples of a possible routinary application of MAS. For more complex traits, like yield and abiotic stress tolerance, a number of constraints have determined severe limitations on an efficient utilization of MAS in plant breeding, even if there are a few successful applications in improving quantitative traits. Recent advances in genotyping technologies together with comparative and functional genomic approaches are providing useful tools for the selection of genotypes with superior agronomical performancies.

Whole-Genome Mapping of Agronomic and Metabolic Traits to Identify Novel Quantitative Trait Loci in Bread Wheat Grown in a Water-Limited Environment

“…Drought stress, which has been identified as the most devastating abiotic constraint on crop productivity (Francia et al, 2005;Reynolds et al, 2005), causes substantial perturbations in plant metabolism (Bowne et al, 2011(Bowne et al, , 2012. Previous QTL studies of agronomic traits in wheat have lacked information on the biochemical pathways underlying those traits and their responses to drought.…”

Strategies for Improving Water Productivity and Quality of Agricultural Crops in an Era of Climate Change

“…Plant tolerance to abiotic stress is mediated by complex traits that are sustained by multiple genetic factors with large QTLs-by-environment interactions. Due to these features, the practical application of marker-assisted selection for stress-related QTLs has proven difficult (Francia et al, 2005). The development of molecular marker technologies will help to identify a particular chromosomal location for genes regulating specific traits.…”

LOW ASSOCIATION OF Bph17 ALLELE IN LANDRACES AND IMPROVED VARIETIES OF RICE RESISTANT TO BROWN PLANTHOPPER

“…The success of MAS such as Bph17 marker depends on several factors, including genetic base of trait, degree of association between molecular marker and target gene, number of individuals analyzed, and genetic background of the target gene to be transferred (Francia et al 2005;Wang et al 2008). DNA markers such as Bph17 need to be evaluated for identifying BPH biotypes.…”