G. RENUGA
Abstract
A plant grow tic promoting bacterium. P7codonionos ant ryinoso that contained high levels of hasty metals was isolated from sod collected tannery effluent seepage near Dindigul 01. The bacterium was resistant to the toxic effects of various metals such as Cr", Ph', lig, Zn and Cd. Lycoperstrunt tuitlentom seeds inoculated with this bacterium and then grown undm genotobiotic condition in the presence of high concentration of potassium chromate were partially protected against chromium toxicity. to addition, protection by the bacterium against chromium toxicity was evident in pot experiments with tomato seeds and tomato seedling. The presence of P. ono 1st.had no measurable influence on the amount of chromium accumulated per milligram (dry weigh 0 of either roots or shoots of tomato plant, Therefore, the bacterial plant growth prompting effect in the presence of chromium was probably not attributable to the reduction of chromium uptake by seedlings, Rather, it may reflect the ability of the bacterium to lower the level of stress ethylene induced by the chromium. Regardless of the precise mechanism used by the bacterium to protect plants, the experiments with plant seedlings reported here suggest that certain bactena may eventually find a use in the development of phytoremediation strategies. In this regard, heavy mends may be removed from polluted suit either by increasing the metal accumulating abkl increasing the metal accumulating ability uf plants or by increasing the amount of plail re,utts reveal that the deleterious effects of chromium taken up from the environment on some might involve the u of plant growth promoting bacteria and also were able to and growth of plants.