Cold-induced Changes in Gene Expression During Dormancy Breakage in Seeds of Douglas Fir (Pseudotsuga menziesii)

1993

S. 120-123

27 Lit. Ang.

Unselbständiges Werk

200050818

The effects of cold, moist treatment (stratification) on dormancy break and associated changes in gene expression were determined for seeds of Douglas fir (Pseudotsuga menziesii). At a germination temperatur of 20 Grad C between 93-95% of the seed population failed to germinate after 42 days. A high percentage of germination (up to 73%) at 20 Grad C only occurred if seeds were first pre-treated at 4 Grad C. RNA was extracted from moist seeds maintained at either 4 Grad C, 15 Grad C or 20 Grad C, and the RNA translated in vitro. The labelled translation products were analysed by two- dimensional gel electrophoresis followed by fluorography. In cold-treated seeds, transcripts encoding abundant translation products appeared after 7 days and reached a maximum level after 14 days. Although these translation products could also be observed on translation of RNA from seeds maintained at 15 Grad C and 20 Grad C (but not immediately following imbibition), the transcript levels in these seeds were increased substantially.