Abstract
Seed germination is widely used as a model to explore toxicity of various harmful chemicals in plants. High concentration of fluoride in water can be harmful for the plant kingdom at all stages of development. Seeds of Tritium aestivum L (wheat) were sown in Petri dishes and exposed to five different concentrations of sodium fluoride (20, 40, 60, 80, and 100 ppm) for two weeks. Seeds grown with distilled water were used as controls for comparison. Germination data for the seedlings was recorded and seedlings were harvested on 15th day after sowing. Freshly prepared extract of seedlings was examined for various biochemical assays (total protein, glutathione (GSH), glutathione 5-transferase activity, and lipid peroxide) and by Fourier transform infrared spectroscopy (FT-IR) analysis. We found a gradual decrease in seed germination parameters as the concentration of sodium fluoride (NaF) increased. All measured biochemical parameters were also effected in dose dependent manner. The total protein level was slightly increased with 20, 40, and 60 ppm of NaF. However, with 80 and 100 ppm of NaF there was a slight decrease as compared to control. Both GSH and GST levels were decreased with increased concentration of NaF while lipid peroxide was increased with 20 ppm of NaF treatment but showed a slight decrease when treated with higher concentrations of NaF. Overall maximum effect was shown by highest NaF level (100 ppm) and moderate tolerance was observed up to 40 ppm. FT-IR profiles revealed some changes in functional groups of proteins, lipids, and carbohydrates with NaF treatments. Future studies on crop tolerance for plants irrigated with groundwater with high fluoride levels are recommended.