Regulation of dormancy in barley by blue light and after-ripening : effects on abscisic acid and gibberellin metabolism

Gubler, Frank , Hughes, Trijntje, Waterhouse, Peter M., & Jacobsen, John (2008) Regulation of dormancy in barley by blue light and after-ripening : effects on abscisic acid and gibberellin metabolism. Plant Physiology, 147(2), pp. 886-896.

View at publisher (open access)


White light strongly promotes dormancy in freshly harvested cereal grains, whereas dark and after-ripening have the opposite effect. We have analyzed the interaction of light and after-ripening on abscisic acid (ABA) and gibberellin (GA) metabolism genes and dormancy in barley (Hordeum vulgare ‘Betzes’). Analysis of gene expression in imbibed barley grains shows that different ABA metabolism genes are targeted by white light and after-ripening. Of the genes examined, white light promotes the expression of an ABA biosynthetic gene, HvNCED1, in embryos. Consistent with this result, enzyme-linked immunosorbent assays show that dormant grains imbibed under white light have higher embryo ABA content than grains imbibed in the dark. After-ripening has no effect on expression of ABA biosynthesis genes, but promotes expression of an ABA catabolism gene (HvABA8′OH1), a GA biosynthetic gene (HvGA3ox2), and a GA catabolic gene (HvGA2ox3) following imbibition. Blue light mimics the effects of white light on germination, ABA levels, and expression of GA and ABA metabolism genes. Red and far-red light have no effect on germination, ABA levels, or HvNCED1. RNA interference experiments in transgenic barley plants support a role of HvABA8′OH1 in dormancy release. Reduced HvABA8′OH1 expression in transgenic HvABA8′OH1 RNAi grains results in higher levels of ABA and increased dormancy compared to nontransgenic grains.

Impact and interest:

92 citations in Scopus
Search Google Scholar™
82 citations in Web of Science®

Citation counts are sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

ID Code: 65869
Item Type: Journal Article
Refereed: Yes
DOI: 10.​1104/pp.107.115469
ISSN: 0032-0889
Subjects: Australian and New Zealand Standard Research Classification > BIOLOGICAL SCIENCES (060000) > PLANT BIOLOGY (060700)
Divisions: Current > Schools > School of Earth, Environmental & Biological Sciences
Current > QUT Faculties and Divisions > Science & Engineering Faculty
Copyright Owner: Copyright 2008 American Society of Plant Biologists
Deposited On: 08 Jan 2014 06:33
Last Modified: 21 Dec 2016 06:25

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page