Fast rejoining processes in Nigella damascena chromosomes revealed by fractionated 60Co γ-ray exposures
| Autor: | J. Moutschen, R. Thakare, J. Gilot-Delhalle |
|---|---|
| Rok vydání: | 1973 |
| Předmět: |
biology
Chemistry Radiochemistry Potassium cyanide chemistry.chemical_element Plant Science biology.organism_classification Oxygen Toxicology chemistry.chemical_compound Dinitrophenol Cupferron Sodium azide Chelation Cobalt-60 Nigella damascena Agronomy and Crop Science Ecology Evolution Behavior and Systematics |
| Zdroj: | Radiation Botany. 13:229-242 |
| ISSN: | 0033-7560 |
| DOI: | 10.1016/s0033-7560(73)80030-4 |
| Popis: | Dry seeds of Nigella damascena were irradiated by 60Co γ-rays with fractionated exposures (2 × 4 krads), separated by time-intervals ranging from 2 to 3 min with increments of 10 sec. At time-intervals longer than 2 min 10 sec, the frequency of chromosome aberrations was found to be considerably decreased. These fast rejoining processes were oxygen dependent, being suppressed under anoxic conditions. Similarly, respiratory inhibitors: potassium cyanide (1 × 104M), sodium azide (1 × 104M) and dinitrophenol (1 × 105M) suppress the decrease. To test the hypothesis that ionic bonds can be involved in fast rejoining processes, seeds were treated respectively with three chelating agents (at 1 × 104M) before irradiation. Dipyridyl (DP) was found to suppress the decrease whereas diethyldithiocarbamate (DIECA) or cupferron (CUPF) produced a reversion at exactly the same tune-interval. The action of chelating agents was proved to be oxygen dependent. It was also demonstrated that all kinds of aberrations of the chromosome class i.e. breaks, minutes, dicentrics or rings were involved in the processes. |
| Databáze: | OpenAIRE |
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