Analysis of Soil Genotoxicity in the City of Ivano-Frankivsk using Nicotiana tabacum Su/+ plants

Soil contamination is the result of rapid urbanization. Since plants are used as food and feed, it is important to analyze the effect of soil contaminants on plant growth. Moreover, plants can also be used to detect genotoxic effects of potential mutagens. Here, we analyzed whether Nicotiana tabacum Su/+ plants that are heterozygous for the Sulfur gene can be used for biomonitoring of potential soil pollution. Leaves of these plants are pale green with occasional appearance of dark green spots. It was previously suggested that the appearance of these spots is the result of DNA damage at the Sulfur locus. Plants were germinated and grown on soil taken from five different areas of one of the Ukrainian cities, Ivano-Frankivsk. The areas were designated as clean (Plot #1 and Plot #2) and contaminated (Plot #3, 4 and 5). We analyzed the dynamics of stem elongation and changes in crown diameter. The analysis showed that plants grown on soil from Plot#5 had the slowest dynamics of both stem and crown growth. The dynamics of stem growth was statistically similar among other four samples. In contrast, the dynamics of crown growth was significantly slower in plants grown on soil from Plot#3 and #1, as compared to Plot#4 and #2. The analysis of spot appearance showed that the highest number of spots and the largest total area of spots were observed in plants from Plot#3. Analysis of index of mutation intensity (IMI) that reflects the percentage of leaf area occupied by mutation spots showed the lowest IMI in plants grown on soil from Plot#1 and 2 and the highest in plants from Plot #3, 4 and 5.