Detection and verification of malting quality QTLs using wild barley introgression lines

Abstract

A malting quality quantitative trait locus (QTL) study was conducted using a set of 39 wild barley introgression lines (hereafter abbreviated with S42ILs). Each S42IL harbors a single marker-defined chromosomal segment from the wild barley accession ‘ISR 42-8’ (Hordeum vulgare ssp. spontaneum) within the genetic background of the elite spring barley cultivar ‘Scarlett’ (Hordeum vulgare ssp. vulgare). The aim of the study was (1) to verify genetic effects previously identified in the advanced backcross population S42, (2) to detect new QTLs, and (3) to identify S42ILs exhibiting multiple QTL effects. For this, grain samples from field tests in three different environments were subjected to micro malting. Subsequently, a line × phenotype association study was performed with the S42ILs in order to localize putative QTL effects. A QTL was accepted if the trait value of a particular S42IL was significantly (P < 0.05) different from the recurrent parent as a control, either across all tested environments or in a particular environment. For eight malting quality traits, altogether 40 QTLs were localized, among which 35 QTLs (87.5%) were stable across all environments. Six QTLs (15.0%) revealed a trait improving wild barley effect. Out of 36 QTLs detected in a previous advanced backcross QTL study with the parent BC2DH population S42, 18 QTLs (50.0%) could be verified with the S42IL set. For the quality parameters α-amylase activity and Hartong 45°C, all QTLs assessed in population S42 were verified by S42ILs. In addition, eight new QTL effects and 17 QTLs affecting two newly investigated traits were localized. Two QTL clusters harboring simultaneous effects on eight and six traits, respectively, were mapped to chromosomes 1H and 4H. In future, fine-mapping of these QTL regions will be conducted in order to shed further light on the genetic basis of the most interesting QTLs.

Genetic regulation of growth and nutrient content under phosphorus deficiency in the wild barley introgression library S42IL

“…First ILs in barley were introduced by Schmalenbach, Körber, and Pillen (). These authors analysed and detected wild barley QTLs of the introgression library S42IL controlling yield‐related traits, malting quality, flowering time and resistance against pathogens (Schmalenbach, Leon, & Pillen, ; Schmalenbach & Pillen, ; Schmalenbach et al., ; Wang et al., ). Later on, the barley ILs were also used to detect QTLs for drought tolerance (Honsdorf, March, Berger, Tester, & Pillen, ; Honsdorf, March, Hecht, Eglinton, & Pillen, ) and nitrogen stress tolerance, which were studied in greenhouses (Schnaithmann & Pillen, ) and in hydroculture (Hoffmann, Maurer, & Pillen, ).…”

Mapping Agronomic Traits in a Wild Barley Advanced Backcross–Nested Association Mapping Population

“…Furthermore, if beneficial alleles are identified, these alleles are already partially introgressed into an adapted background. This technique has been used by barley researchers to identify beneficial alleles from wild barley sources for many traits of interest including yield and agronomic traits (Li et al, 2005; Von Korff et al, 2006; Gyenis et al, 2007; Eshghi et al, 2013), malting quality (Von Korff et al, 2008; Schmalenbach and Pillen, 2009; March et al, 2012), disease resistance (Von Korff et al, 2005; Yun et al, 2006; Li et al, 2006), abiotic stress tolerance (Saal et al, 2011; Hoffmann et al, 2012; Schnaithmann and Pillen, 2013; Kalladan et al, 2013), and root traits (Naz et al, 2014).…”

Barley

“…hordei L.) and leaf rust ( Puccinia hordei L.) (Schmalenbach et al 2008 ). In addition, QTLs were verifi ed in these ILs affecting malting quality parameters (Schmalenbach and Pillen 2009 ). It was validated that wild barley alleles at the chromosome 1H QTL reduced overall malting quality, whereas wild barley alleles at the chromosome 4H QTL improved the malting quality parameters compared to the control genotype Scarlett (March et al 2012 ).…”