Complex G × E Interactions and QTL Clusters Govern End-Use Quality Traits in Hexaploid Wheat

Abstract

Evaluation of wheat end-use quality in terms of loaf volume (LV) requires enormous time and labor inputs. Hence, many studies have attempted to use grain, flour and dough properties to predict LV. Many quantitative trait loci (QTL) underlying these traits have also been identified to facilitate breeding. However, correlations between such predictive tests and LV as well as their QTLs could be influenced by the environment. In this chapter, we review recent literature on the correlations and G × E interaction (GEI) of the bread making quality traits grain protein content (GPC), sodium dodecyl sulphate sedimentation volume (SV), dough rheological traits (DRT) and LV. We briefly discuss our results from the evaluation of a hexaploid wheat recombinant inbred line population for GPC, SV, LV and nine DRT by mixograph analysis in six year-location environments in India, which revealed that correlations between DRT and LV were not stable across environments. In addition, GEI measured in terms of principal components using Additive main effects and multiplicative interaction model showed up to 47 % contribution to the total variation of the traits, which was reflected in the location-specificity of QTLs expressed in single as well as multiple environments. Even though 16 QTL clusters for four to seven traits were identified, only one of them involved LV. The strong influence of the environment on complex interrelationships between DRT and the other end-use quality traits suggested that during breeding for wheat end-use quality, marker-based selection of these traits would be more efficient if specific agro-climatic zones are targeted separately.