Cytogenetic effects of Fulvic acid on Allium cepa L. root tip meristem cells

Fulvic acid is a class of compounds of humic substances and is found in a significant proportion of the substances in the environment. It has been used for many years in industry, agriculture, and complementary medicine. In this study, cytogenetic effects of fulvic acid purified from Mugla Milas Husamlar leonardite (TURKEY) on Allium cepa root tip meristem cells were investigated using the Allium test. For this purpose, 10 mg/ml stock solution of fulvic acid was prepared by dissolving in citric acid and it was diluted with distilled water to 10, 20, 40, 80 and 100 mu g/mL concentrations. Onion bulbs were exposed to these concentrations of the fulvic acid for macroscopic and microscopic analysis. Tap water was used as a negative control, 40 mu g/mL citric acid was used as solvent control (fulvic acid solvent), and 0.02M Ethyl methane sulfonate (EMS) (a mutagenic, teratogenic, and possibly carcinogenic organic compound) was used as a positive control. There has been statistically significant stimulation of root growth depending on fulvic acid concentration in comparison with the control groups (p<0.05). Furthermore, in fulvic acid treatment groups, breaks, stickiness and polar deviations appeared at very low rates, and total chromosome aberration ratios were insignificant compared to the control groups. These results suggest that fulvic acid does not have cytotoxic and genotoxic effects on A. cepa.