Characterization of the sdw1 semi-dwarf gene in barley

Abstract

BackgroundThe dwarfing gene sdw1 has been widely used throughout the world to develop commercial barley varieties. There are at least four different alleles at the sdw1 locus.ResultsMutations in the gibberellin 20-oxidase gene (HvGA20ox2) resulted in multiple alleles at the sdw1 locus. The sdw1.d allele from Diamant is due to a 7-bp deletion in exon 1, while the sdw1.c allele from Abed Denso has 1-bp deletion and a 4-bp insertion in the 5’ untranslated region. The sdw1.a allele from Jotun resulted from a total deletion of the HvGA20ox2 gene. The structural changes result in lower gene expression in sdw1.d and lack of expression in sdw1.a. There are three HvGA20ox genes in the barley genome. The partial or total loss of function of the HvGA20ox2 gene could be compensated by enhanced expression of its homolog HvGA20ox1and HvGA20ox3. A diagnostic molecular marker was developed to differentiate between the wild-type, sdw1.d and sdw1.a alleles and another molecular marker for differentiation of sdw1.c and sdw1.a. The markers were further tested in 197 barley varieties, out of which 28 had the sdw1.d allele and two varieties the sdw1.a allele. To date, the sdw1.d and sdw1.a alleles have only been detected in the modern barley varieties and lines.ConclusionsThe results provided further proof that the gibberellin 20-oxidase gene (HvGA20ox2) is the functional gene of the barley sdw1 mutants. Different deletions resulted in different functional alleles for different breeding purposes. Truncated protein could maintain partial function. Partial or total loss of function of the HvGA20ox2 gene could be compensated by enhanced expression of its homolog HvGA20ox1 and HvGA20ox3. Electronic supplementary materialThe online version of this article (doi:10.1186/s12870-016-0964-4) contains supplementary material, which is available to authorized users.

A connected half‐sib family training population for genomic prediction in barley

“…The MTA for height on 3H may be linked to the sdw1 locus, a commonly used semidwarfing gene in European malting barley. This locus encodes a gibberellin 20‐oxidase‐2 gene ( HvGA20ox2 ) and has been cloned (Xu et al., 2017). The marker identified on 3H lies within 0.58 Mb of HvGA20ox2 (634,077,598–63,4081,600 bp).…”

Novel loci and a role for nitric oxide for seed dormancy and preharvest sprouting in barley

“…Furthermore, the HvGA2ox4 and HvGA20ox3 genes were significantly associated with dormancy, located on 1H and 3H, respectively. HvGA20ox genes are best known for their effects on PH; mutations are found in dwarf and semidwarf phenotypes (Xu et al, ), and HvGA20ox genes apparently also strongly influence dormancy release. A strong relationship between PH and dormancy was not found.…”

“…HvGA20ox genes are best known for their effects on PH; mutations are found in dwarf and semidwarf phenotypes (Xu et al, 2017), and…”

Genetics of barley tiller and leaf development

“…In ideotype breeding, it is necessary also to consider the correlations among different traits, often resulting from pleiotropy, epistasis or linkage of the underlying loci, and compensatory physiological and developmental mechanisms (Chandler and Harding ; Rebolledo et al ). As a successful example, Green Revolution cultivars, with their reduced plant stature, showed an increase in grain yield performance in intensive agriculture compared with traditional cultivars, and this was mainly due to the improved lodging resistance and enhanced nitrogen use efficiency (Gooding et al ; Xu et al ). In the following sections, we focus on the target traits already discussed, overviewing how the optimization of these traits can improve crop performance and yield (Zhu et al ; Mathan et al ; Wang et al ).…”