Identification of QTLs controlling grain protein concentration using a high-density SNP and SSR linkage map in barley (Hordeum vulgare L.)

Abstract

BackgroundGrain protein concentration (GPC) is a major determinant of quality in barley (Hordeum vulgare L.). Breeding barley cultivars with high GPC has practical value for feed and food properties. The aim of the present study was to identify quantitative trait loci (QTLs) for GPC that could be detected under multiple environments.ResultsA population of 190 recombinant inbred lines (RILs) deriving from a cross between Chinese landrace ZGMLEL with high GPC (> 20%) and Australian cultivar Schooner was used for linkage and QTL analyses. The genetic linkage map spanned 2353.48 cM in length with an average locus interval of 2.33 cM. GPC was evaluated under six environments for the RIL population and the two parental lines. In total, six environmentally stable QTLs for GPC were detected on chromosomes 2H (1), 4H (1), 6H (1), and 7H (3) and the increasing alleles were derived from ZGMLEL. Notably, the three QTLs on chromosome 7H (QGpc.ZiSc-7H.1, QGpc.ZiSc-7H.2, and QGpc.ZiSc-7H.3) that linked in coupling phase were firstly identified. Moreover, the genetic effects of stable QTLs on chromosomes 2H, 6H and 7H were validated using near isogenic lines (NILs).ConclusionsCollectively, the identified QTLs expanded our knowledge about the genetic basis of GPC in barley and could be selected to develop cultivars with high grain protein concentration.Electronic supplementary materialThe online version of this article (doi:10.1186/s12870-017-1067-6) contains supplementary material, which is available to authorized users.

Dissection of two quantitative trait loci with pleiotropic effects on plant height and spike length linked in coupling phase on the short arm of chromosome 2D of common wheat (Triticum aestivum L.)

“…Neighbouring QTL that are linked in coupling phase are commonly observed in primary QTL analysis (Fan et al 2017; Wu et al 2015). To date, many studies have tried to dissect QTL in coupling phase using NILs or residual heterozygous lines and found that coupling QTL were partially attributed to tightly linked independent QTL (Chemayek et al 2017; Shen et al 2011).…”

Cisgenic overexpression of cytosolic glutamine synthetase improves nitrogen utilization efficiency in barley and prevents grain protein decline under elevated CO2

“…This may be the case even though down‐regulation of GS1 expression under CO 2 enrichment has been reported for different TaGS1 isogenes in wheat (Buchner et al ., ; Vicente et al ., , ), possibly reflecting a decrease in NH 4 + (El Omari et al ., ; Funayama et al ., ; Goodall et al ., ; Guan et al ., ; Konishi et al ., ). The results for the cisgenic lines corroborate the importance of GS1 in maintaining grain protein concentration, as has also been highlighted through identification of QTLs in barley (Fan et al ., ) and via a positive correlation between GS activity and grain protein content in wheat cultivars (Nigro et al ., ; Zhang et al ., ). Considering the fact that extra N supply cannot offset the decline in grain protein concentration of wheat plants growing in an elevated CO 2 environment (Tausz et al ., ; Walker et al ., ), overexpression of HvGS1‐1 may thus provide a means to prevent declining grain protein concentration under elevated atmospheric CO 2 .…”

Construction of a high-density genetic map: genotyping by sequencing (GBS) to map purple seed coat color (Psc) in hulless barley

“…The quality of genetic maps, however, can significantly affect the accuracy of gene mapping. This increases the density of markers distributed around the entire genome, which can improve the resolution of genetic maps [ 31 – 33 ]. SSR, one of the traditional gene mapping methods, was used in hulless barley, but the number of SSR markers is limited.…”