Identification and validation of quantitative trait loci for grain protein concentration in adapted Canadian durum wheat populations

Abstract

Grain protein concentration (GPC) is one of the most important factors influencing pasta-making quality. Durum wheat (Triticum turgidum L. var durum) cultivars with high GPC produce pasta with increased tolerance to overcooking and greater cooked firmness. However, the large environmental effect on expression of GPC and the negative correlation with grain yield have slowed genetic improvement of this important trait. Understanding the genetics and identification of molecular markers associated with high GPC would aid durum wheat breeders in trait selection at earlier generations. The objectives of this study were to identify and validate molecular markers associated with quantitative trait loci (QTL) for elevated GPC in durum wheat. A genetic map was constructed using SSR and DArT markers in an F(1)-derived doubled haploid (DH) population derived from the cross DT695 x Strongfield. The GPC data were collected from replicated trials grown in six Canadian environments from 2002 to 2005. QTL associated with variation for GPC were identified on the group 1, 2, and 7 chromosomes and on 5B and 6B, but only QGpc.usw-B3 on 2B and QGpc.usw-A3 on 7A were expressed consistently in four and six environments, respectively. Positive alleles for GPC at these loci were contributed by the high-GPC parent Strongfield. The QGpc.usw-A3 QTL was validated in a second DH population, and depending on environment, selection for the Strongfield allele at barc108 resulted in +0.4% to +1.0% increase in GPC, with little effect on yield in most environments. Given the consistent expression pattern in multiple populations and environments, barc108 could be useful for marker-assisted selection for high GPC.

A major QTL for resistance to soil-borne cereal mosaic virus derived from an old Italian durum wheat cultivar

“…Neodur are expected to be found when sequence-specific markers will be developed from the sequence of the DArT markers positioned at the peak of the QTL. The scarcity of PCR-based molecular markers in the region where the major QTL for resistance was identified in the present study is a common feature of a number of linkage maps that have been developed in both bread and durum wheat (Huynh et al 2008;Mantovani et al 2008;Suprayogi et al 2009;Genc et al 2010); therefore, although not optimal, the Xbcd348 and Xgwm1128 markers identified in the present study represent a useful panel for the prediction of resistance/susceptibility to SBCMV in durum wheat.…”

QTL detection for wheat kernel size and quality and the responses of these traits to low nitrogen stress

“…A comparison of wheat grain yield and yield component selection has shown that selection for kernel weight could result in an increase in grain yield (Alexander et al 1984). However, an increase in yield often results in a decrease in kernel quality parameters, such as a lower grain protein content (GPC), because of a dilution effect (Suprayogi et al 2009). Notably, previous studies have shown that quantitative trait loci (QTLs) for yield are not always negatively correlated with quality (Sourdille et al 2003;Huang et al 2006;Kunert et al 2007;Echeverry-Solarte et al 2015).…”

“…GPC, particularly glutenin and gliadin content is controlled by a complex genetic system and is strongly affected by the environment. It is an important factor for pasta-making and baking quality and is strongly correlated with WGC, DT, ABS, and ZEL (Zanetti et al 2001;Nelson et al 2006;Suprayogi et al 2009;Li et al 2011). KH, one of the most important determinants of milling yield, has profound effects on the milling, baking and enduse quality of bread wheat ).…”

“…KH, one of the most important determinants of milling yield, has profound effects on the milling, baking and enduse quality of bread wheat ). Numerous studies have identified an association between high-and lowmolecular-weight (HMW/LMW) glutenin loci (Glu-A1, Glu-B1, and Glu-D1/Glu-A3, , and wheat quality, and these loci are located on the long/short arms of the homoeologous group 1 chromosomes (Perretant et al 2000;Sourdille et al 2003;Kuchel et al 2006;Li et al 2009;Mann et al 2009;Suprayogi et al 2009;Sun et al 2010;Reif et al 2011;Echeverry-Solarte et al 2015). In addition, the Ha locus on chromosome 5DS and the Gpc-B1 locus on chromosome 6BS have also been reported to exhibit strong correlations with processing and end-use quality (Sourdille et al 1996(Sourdille et al , 2003Perretant et al 2000;Campbell et al 2001;Igrejas et al 2002;Turner et al 2004;Nelson et al 2006;Kunert et al 2007;Li et al 2009;Sun et al 2010).…”

“…An adequate quantity of nitrogen (N) and an appropriate time of application can improve yield and quality; however, the use of N fertilizer leads to an increased cost as well as environmental consequences, such as groundwater pollution due to nitrate leaching (Laperche et al 2007(Laperche et al , 2008Suprayogi et al 2009;Cui et al 2014a). Wheat varieties that maintain a high yield and quality under moderate or even severe N deficiency can be adapted for use in low-input management systems.…”