Effect of Fluoride on anatomical structure of vegetative organs in Phaseolus vulgaris L

Fluoride is a toxic solution for the nature and enters environment from different sources. Aluminum industry is the most important source of fluoride which empties to the nature as sodium fluoride, hydrogen fluoride, gas components of fluoride and fluoride particles causing damaging effects on plants, animals and the humans. In this research, toxic effect of sodium fluoride as a nature pollutant has been examined on bean Phaseolus vulgaris. At first, bean seeds were exposed to different concentrations of sodium fluoride (0.2, 0.5, 1 and 2 mg/100 cc water) while three other treatments put aside because of high toxicity of the solution and anti-germinative effects in these concentrations. In the second stage, we applied new solutions with concentrations of 0.5, 0.8 and 1.2 mg/l sodium fluoride for germination and tilling the seeds, and just watered the controls. In vegetative phase, damaging effects of NaF during daily irrigation were observed as necrosis, chlorosis and wounds on leaf blade, early senescence and plants fading. Increase in root and shoot length and decrease in generation rate and root ramification also could be attributed to NaF. Delay in transition of shoot apex from vegetation phase to generation phase was another observed effect of fluoride treatment.