QTL and association mapping for plant abiotic stress tolerance: trait characterization and introgression for crop improvement

Abstract

Nutrient deficiencies, toxicities, cold, drought, and heat stress are widespread problems in agriculture areas. In order to survive and produce under highly variable environments, plants have developed multiple strategies and mechanisms of tolerance. The majority of traits associated with abiotic stress tolerance in plants are quantitative with complex phenotype and genetic control. Although quantitative genetics approaches are best suited to discover new genes, the success of such approaches depends largely on the complexity of the trait. Quantitative trait loci (QTL) detection is the observation of a significant relationship or genetic linkage between the alleles at a specific locus or genomic region and the variation in a quantitative trait. The identified QTL may not show similar effects in high-yielding varieties and this may limit their use in crop improvement. Ideally, the effect of a QTL should be measured in several populations prior introgression.