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Phytotoxicity of colloidal solutions of metal-containing nanoparticles (Ag, Cu, Fe, Zn, Mn) has been investigated using a standard Allium cepa (L.) test system. Toxicity of experimental solutions at the organism level was evaluated in terms of biomass growth of onion roots, and cytotoxicity was estimated by the mitotic index of root meristem cells. The colloidal solutions of metal nanoparticles inhibited the growth of Allium cepa (L.) roots due to their ability to penetrate into cells and interact with their components, and thus to inhibit mitosis. According to our results cytotoxicity of test solutions decreases in the following order: Cu > or = Zn > Ag > or = Fe. Solution of Mn-containing nanoparticles revealed physiological activity according to root growth reaction.

Chlorophenols are precursors to more dangerous toxicants dioxanes and are characterized wiht mutagenic and carcinogenic properties. Mutagenicity and cytotoxicity of chemical substances can be studied using methods of plant biological testing under the influence of different pollutants. Genotoxic and cytotoxic effects of pentachlorophenol and 3-chlorophenol solutions in root meristem cells of Allium fistulosum (L.) were investigated. Dose-dependent inhibition of onion seed germination under the influence of 5-chlorophenol and 3-chlorophenol solutions in different concentrations was revealed. Pentachlorophenol showed significantly greater dose-dependent toxic effect on seed germination than 3-chlorophenol.

The antimutagenic activities of the oils obtained from leaves and fruits of Fagus orientalis have been shown in experiments with spontaneous and mutagen- and ageing-induced variability. The aberrations of chromosomes in the meristematic cells of the Allium cepa L., Vicia faba L., Triticum aestivum L., and marrow cells of Vistar rats as well as Arabidopsis thaliana gene mutations have been mobilized as experimental tests.

The widespread use of the herbicides for weed control and crop productivity in modern agriculture exert a threat on economically important crops by way of cytological damage to the cells of the crop plant or side effects, if any, induced by the herbicides. In the present communication, author describes the effects of 2,4-D and Isoproturon on chromosomal morphology in mitotic cells of Triticum aestivum L. The wheat seedlings were treated with range of concentrations (50-1200 ppm) of 2,4-D and Isoproturon for 72 h at room temperature. In the mitotic cells, twelve distinct chromosome structure abnormalities were observed over control. The observed irregularities were stickiness, c-mitosis, multipolar chromosomes with or without spindles, fragments and bridges, lagging chromosomes, unequal distribution of chromosomes, over contracted chromosomes, unoriented chromosomes, star shaped arrangement of the chromosomes, increased cell size and failure of cell plate formation. The abnormalities like stickiness, fragments, bridges, lagging or dysjunction, unequal distribution and over contracted chromosomes meet frequently.

It was shown that sodium humate in a range of concentration of 50-1000 mg/l reduces a level of clastogenic effects induced with dioxidin (20 mg/l), a prooxidant mutagene. The greatest effect was observed at concentration of 300 mg/l. Direct doze-effect dependence under the influence of sodium humate was not revealed. Possible antioxydative and desmutagenic mechanisms of sodium humate protective action are discussed.

Intracellular distribution of assimilated 2,4,6-trinitrotoluene (TNT) in callus cells, flower buds and leaves of intact Yucca gloriosa L. plants using electron microscope radioautography. The radiotracer was detected in vacuoles, plastids, mitochondrion, endoplasmic reticulum and cytoplasm. It was found that in dedifferentiated callus cells TNT was incorporated in the vacuoles in greater quantities in comparison with the cells of intact plant. Correspondingly the ultrastructural integrity of the dedifferentiated cells is less damaged.

The influence of different concentrations of cadmium and potassium on the levels of mutagenic and cytotoxic effects induced by thallium-232 in Allium cepa root meristem has been studied. The combined action of 232Th (0.8 microM) with cadmium in non-toxic (0.009 microM) and toxic (5 microM) concentrations resulted in sinergetic increase of the frequency of aberrant cells in Allium cepa root meristem. Decrease of the mutagenic effect to the additive level and antagonism with respect to the cytotoxic one was observed only at the certain concentrations of 232Th (0.8 microM) and Cd (0.09 microM) and the time of impact 30 h. In contrast to the heavy metal cadmium the essential for plants potassium at all studied concentrations (0.008, 6, 13 mM) decreased the number of cytogenetic aberrations in control experiments and under the effect of 232Th. The maximum protective effect of potassium was detected at the concentration 13 mM.

The influence of dioxidin in different concentrations (10-100 mg/l) on the cytogenetic parameters of Allium cepa L. has been studied. The mutagenic effect of dioxidin was shown within all the range of the studied concentrations. The curve "dose-effect" has been determined for the concentrations of 10, 20, 30, 40, 50, and 100 mg/l. The peak of the mutagenic effect and significant reduction of the mitotic index were revealed at the concentration of 100 mg/l. It was shown that the mutagenic efficiency of the dioxidin statistically correlated with reduction of the mitotic activities.

Study of total mutagenic effects of liquid fluorine-organic waste products of monomer FC-141 manufacture has been carried out. Induction of gene mutations according to the mechanism of pair base replacement and shift of reading frame and induction of chromosomal aberrations, in particular deletions and translocations, has been shown. Expediency of use of natural sorbents for mutageneity removal from fluorine-organic waste products was investigated. Zeolites and glauconites appeared to be the most effective ones.

The average number of aberrations per aberrant cell was concluded to carry out information on chromosome instability peculiarities induced by different mutagens as it was shown in our previous work. The purpose of the current study was to present comparative analysis of intercellular distribution of number of aberrations and their theoretical approximations. Distribution of numbers of aberrations per cell in Allium cepa L. and Allium fistulosum L. root tip cells induced by different mutagenic factors (gamma-irradiation, thiotepa, formaldehyde and seed aging) have been studied. The results were approximated to theoretical Poisson, geometric and negative binomial distributions. The intercellular distribution of aberrations did not correspond to any of the used theoretical distributions when A. cepa seeds were gamma-irradiated. There was some, but not regular, accordance with theoretical distributions when chemical mutagens thiotepa in A. cepa and formaldehyde in A. fistulosum and seed aging in both species were evaluated. During seed aging frequency of aberrant cells increased more quickly in A. fistulosum in comparison with A. cepa.

The reaction of pea (Pisum sativum L.) seedlings on the test--action (gamma-radiation) depending on a phase of seedling reaction on modifying action of cadmium ions was investigated. The existence of correlation between growth rate of the seedling main root and proliferative activity of root apex meristem and the type of radiomodificating effect was established. Radioprotective (radioadaptation) effect was observed at the 5 Gy dose irradiation of the seedlings at the final moment of hypercompensatory phase of the growth reaction on the action of 0.625 MkM CdSO4.

The short-time (30 hours) and chronic (30 days) 232Th and Cd combined effects on Tradescantia and Allium cepa plants were investigated. The 232Th ion concentration was equal to 0.18 mg/l and Cd ion--to 60 mg/l. The early response of both somatic and generative plant cells on Th and Cd combined action was shown to appear in synergic increase of cytogenetic damage frequency. The level of genotoxic and cytotoxic long-term effects turned out to be lower than of the additive one both under the chronic as under the short-time action. These similar in result responses occur on different biological organization levels: in the case of short-time action the effects observed are detected by the intracellular compensatory processes, and in the case of chronic action by the mass death of the most damaged buds in the inflorescence.

The results of comparative analysis of cytogenetic effects of various chemical and physical factors on meristemic cells of field pea (Pisum sativum L.) are presented. Cytogenetic effects of aluminum, cadmium and selenium compounds as well as X-ray irradiation were studied. Cytogenetic indices were investigated for different doses of the above factors and peculiarities of their influence on the ratio of mitotic phases were analyzed. The increasing in the proportion of cells at the specific mitotic stage was revealed. There were anaphase stage for aluminum chloride, prophase stage for cadmium chloride, meta- and anaphase stages for sodium selenate, and telophase stage for X-rays. Investigated chemical elements may be ranged according to their ability to induce the aberrant anaphase frequency in the row: Se (from 3.75 x 10(-6) M) > A1 (from 3.86 x 10(-5) M) > Cd (from 8.44 x 10(-5) M). Maximal experimental dose of X-ray irradiation (9.03 x 10(-3) C/kg) induces the frequency of chromosome aberration similar to those induced by maximal experimental doses of aluminum and selenium (3.86 x 10(-4) M and 8.34 x 10(-6) M).

Comparative analysis of the influence of the salts of Cd, Pb, Ni, Al, Cu and Zn at concentrations 10(-6)-10(-3) M on cytogenetic parameters of Allium cepa apical meristem cells was carried out. It was shown that these metal compounds could induce both the clastogenic and the aneugenic effects (including mitosis and cytokinesis disturbances). Based on ability to cause the chromosome aberrations the metal salts were arranged in such row of genotoxicity: ZnSO4 > Pb(CH3COO)2 > Al(NO3)3 approximately NiSO4 > CdCl2 > CuSO4. The investigated compounds of cadmium, lead, nickel and aluminum were found to be more effective aneugens than clastogens. According to our data NiSO4 had the strongest antimitotic activity (it increased the percentage of chromosome lagging of, multipolar anaphases, C-mitoses in 69.6 times, compared to the control). The ability of other metal salts to induce such abnormalities decreased in the range: CdCl2 > Al(NO3)3 > Pb(CH3COO)2 > CuSO4 > ZnSO4. Increasing of binuclear cells on the slides was revealed after treatment by all tested substances, however Ni sulfate was found as the strongest inducer of cytokinesis abnormalities. Presented results allowed to suggest that cytoskeleton could be a cell target for salts of some metals (especially for NiSO4).

The effects of different concentrations (10(-6)-10(-3) M) of salts of six metals (cadmium, lead, nickel, aluminum, copper, and zinc) on the root growth of onion (Allium cepa L.) seedling and cell division, chromosome and nucleus morphology in root tip cells were studied. The obtained results showed that tested compounds inhibit the root growth, reduce the mitotic activity of meristem cells and cause the chromosome and nucleus irregularities. On the basis of these data two rows of metal salt toxicity were proposed--for effective concentrations (EC50) of toxic action: CuSO4 > CdCl2 > NiSO4 > Pb(CH3COO)2 > Al(NO3)3 > ZnSO4, and for sublethal and lethal effects of investigated substances: CuSO4 > Pb(CH3COO)2 > CdCl2 > ZnSO4 > NiSO4 > Al(NO3)3.