Abstract
Five cold temperature germinating (ctg) mutants, completing germination at 10°C faster than wild type, have been recovered from activation-tagged populations of Arabidopsis thaliana. Three (ctg10-D, 41-D, and 144-D) were tagged and segregated 3:1 for BASTA resistance in the F2 when crossed with wild type. None of the tagged ctg mutants was disturbed in sensitivity to abscisic acid or glucose but all were less sensitive to GA4+7 and osmoticum. The other two mutants (ctg156 and ctg225) were recessive, BASTA sensitive, and exhibited a transparent testa (tt) phenotype. They were more sensitive to abscisic acid, paclobutrazol, and GA4+7 than wild type but had similar sensitivity to osmoticum. Dimethylaminocinnamaldehyde staining of seeds from the two tt mutants, compared with stained seeds from the publicly available if lines 1-10, suggested that ctg156 was a new allele of tt1, while ctg225 was similar to tt7-1. However, reciprocal crosses determined that ctg156 was not allelic to tt1 while ctg225 was a new allele of tt7. When the gene was sequenced from ctg225 it was missing 10 bp in the second exon, resulting in the incorporation of two spurious amino acids (G282E and D283A) followed by a stop. The screen successfully recovered mutants completing germination faster than wild type at 10°C.
Original language | English |
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Pages (from-to) | 2059-2069 |
Number of pages | 11 |
Journal | Journal of Experimental Botany |
Volume | 56 |
Issue number | 418 |
DOIs | |
State | Published - Aug 2005 |
Bibliographical note
Funding Information:This research was supported by a pilot project and a full research grant to ABD from the Kentucky Tobacco Research and Development Center. The mutant screen is part of a project conducted by Mr Louai Salaita performed in partial fulfillment of the requirements for the Undergraduate Agricultural Biotechnology Program, University of Kentucky, Lexington, KY, 40546-0312, USA. The activation-tagged lines, transparent testa mutants, tt1 to tt10, and the Columbia WT were all acquired from The Arabidopsis Biological Resource Center, The Ohio State University, Columbus, OH, USA. Dr Robert Geneve and Mr Manjul Dutt developed the software to run the flatbed scanner. Dr Sharyn Perry kindly permitted the use of her dissecting scope, digital camera, computer, and paclobutrazol. Thanks to Dr Hiro Nonogaki, Oregon State University, for making available some unpublished research findings. An anonymous reviewer provided many suggestions for the improvement of this manuscript. This article (04-11-152) is published with the approval of the Director of the Kentucky Agricultural Experiment Station and has benefited from comments by members of the University of Kentucky, Seed Biology Program.
Keywords
- Activation tag
- Mean germination time
- Seed germination
- Transparent testa
ASJC Scopus subject areas
- Physiology
- Plant Science