Genetic characterisation of dough rheological properties in a wheat doubled haploid population: additive genetic effects and epistatic interactions

Abstract

Doubled haploid lines (n = 160) from a cross between wheat cultivars 'Cranbrook' (high dough extensibility) and 'Halberd' (low dough extensibility) were grown at three Australian locations. The parents differ at all high- and low-molecular-weight glutenin loci. Dough rheological parameters were measured using small-scale testing procedures, and quantitative trait locus (QTL) mapping procedures were carried out using an existing well-saturated genetic linkage map for this cross. Genetic parameters were estimated using three software packages: QTLCartographer, Epistat and Genstat. Results indicated that environmental factors are a major determinant of dough extensibility across the three trial sites, whereas genotypic factors are the major determinants of dough strength. Composite interval mapping analysis across the 21 linkage groups revealed that as expected, the main additive QTLs for dough rheological properties are located at the high- and low-molecular-weight glutenin loci. A new QTL on chromosome 5A for M-extensibility (a mixograph-estimated measure of extensibility) was detected. Analysis of epistatic interactions revealed that there were significant conditional epistatic interactions related with the additive effects of glutenin loci on dough rheological properties. Therefore, the additive genetic effects of glutenins on dough rheological properties are conditional upon the genetic background of the wheat line. The molecular basis of the interactions with the glutenin loci may be via proteins that modify or alter the gluten protein matrix or variations in the expression level of the glutenin genes. Reverse-phase high performance liquid chromatography analysis of the molar number of individual glutenin subunits across the population showed that certain conditional epistases resulted in increased expression of the affected glutenin. The epistatic interactions detected in this study provide a possible explanation of the variable genetic effects of some glutenins on quality attributes in different genetic backgrounds and provide essential information for the accurate prediction of glutenin related variance in marker-assisted wheat breeding.

Estimation of epistasis in doubled haploid barley populations considering interactions between all possible marker pairs

“…Epistasis as an important genetic basis of complex phenotypes has also been revealed in several recent QTL mapping studies Yu et al 1997;Ma et al 2005;Liu et al 2011;Rahman et al 2011;Borràs-Gelonch et al 2012;Krajewski et al 2012). However, marker-based analyses for estimation of QTL effects usually assume the absence of epistasis among QTLs (Lander and Botstein 1989;Jansen 1993;Zeng 1994;Bocianowski and Krajewski 2009;Rovaris et al 2011).…”

Detection of quantitative trait loci for paste viscosity characteristics based on the doubled haploid progeny from a cross between two Chinese wheat varieties

“…However, this approach usually leaves out many QTL that may have no additive effects, but influence the trait only through epistatic interactions or QTL )environment interactions (QEs) (Ma et al 2005(Ma et al , 2007Rebetzke et al 2007). Additive QTL, epistatic QTL, and QEs were detected using twoloci analyses in both the populations (Kulwal et al 2005).…”

A Novel Chimeric Low-Molecular-Weight Glutenin Subunit Gene From the Wild Relatives of Wheat Aegilops kotschyi and Ae. juvenalis: Evolution at the Glu-3 Loci

“…T HE wheat storage proteins named glutenin and gliadins are the major storage proteins in wheat endosperm and are the main determinants for breadmaking quality (Payne et al 1987;Ma et al 2005). These proteins are heterogeneous in composition and exist in at least 50 individual components separable by electrophoretic techniques .…”