Abstract
Dormancy allows wild barley grains to survive dry summers in the Near East. After domestication, barley was selected for shorter dormancy periods. Here we isolate the major seed dormancy gene qsd1 from wild barley, which encodes an alanine aminotransferase (AlaAT). The seed dormancy gene is expressed specifically in the embryo. The AlaAT isoenzymes encoded by the long and short dormancy alleles differ in a single amino acid residue. The reduced dormancy allele Qsd1 evolved from barleys that were first domesticated in the southern Levant and had the long dormancy qsd1 allele that can be traced back to wild barleys. The reduced dormancy mutation likely contributed to the enhanced performance of barley in industrial applications such as beer and whisky production, which involve controlled germination. In contrast, the long dormancy allele might be used to control pre-harvest sprouting in higher rainfall areas to enhance global adaptation of barley.
Highlights
Dormancy allows wild barley grains to survive dry summers in the Near East
We show that a single amino acid substitution in this enzyme reduces the dormancy period of mature barley grain
For the initial mapbased cloning of Qsd[1], we identified a genetic substitution line carrying the long dormancy qsd[1] allele of H602, together with Haruna Nijo’s short dormancy alleles for the other three QTLs13,14
Summary
Dormancy allows wild barley grains to survive dry summers in the Near East. We isolate the major seed dormancy gene qsd[1] from wild barley, which encodes an alanine aminotransferase (AlaAT). The AlaAT isoenzymes encoded by the long and short dormancy alleles differ in a single amino acid residue. The reduced dormancy allele Qsd[1] evolved from barleys that were first domesticated in the southern Levant and had the long dormancy qsd[1] allele that can be traced back to wild barleys. The wild barley’s long dormancy means that, initially, the grain will not germinate in response to transient moisture availability and will survive hot, dry summers. We have identified a gene that defines a major dormancy trait in wild ancestral forms of barley and show that it encodes alanine aminotransferase, which has not previously been linked with dormancy in plants. Our data suggest that the qsd[1] gene for long dormancy appears to be a mutable gene that is used for adaptation to different environments and this is consistent with the large variation in qsd[1] sequence that exists in nature
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
