The effect of tetracyclines on mitosis's pathology in the cells of root meristem Allium cepa L.

The effect of tetracyclines (tetracycline and doxycycline) on genetic apparatus damage in the cells of root meristem Allium cepa L. in the first metaphase after processing and after finishing the recovery period is investigated. Research methods: Allium test, cytogenetic analysis, statistical analysis. The experiment was conducted on a batch of the Stuttgarten variety which is genetically unstable as the result of micronucleus test. It's indicated that the reaction of the tested material to the effect of tetracyclines depends on the concentration and duration of antibiotics. Aneugenic type aberrations such as mitosis, chromatic agglutination up to the formation of clots were prevailing in the cycling cells. An increase in the proportion of PM (chromatic agglutination, various bridges), the result of which is nucleus pycnosis and cell death was indicated for this genotype after the recovery period. It's observed that after the recovery period there is a significant increase of cells with mitosis under the influence of tetracycline in the concentration of 20.0 mg/l, on exposure of 23 and 48 hours. The negative influence of tetracycline in the concentration of 100.0 mg/l was investigated, PM value reached 64.2%; the decrease of cells with PM wasn't observed after the recovery period. In both cases cells with mitosis and chromatic agglutination were dominating. Doxycycline effect in the concentration of 20.0 and 100.0 mg/l caused the doubling of PM in comparison with control. After the recovery period a number of cells regardless of experienced concentration grew due to the increased number of cells with mitosis and chromatic agglutination. It's necessary to mention different effects of meristematic cells of onion roots under the action of structural isomer which are tetracycline and doxycycline. It's worth mentioning that the increase in concentration of bacteriostatic antibiotic (tetracycline and doxycycline) is necessary for maximum inactivation on the one hand. On the other hand, negative processes increase in the cells of eukaryotic organisms during the passage of the cell cycle, particularly, mitosis.