Organic Soil Amendments: Potential Source for Heavy Metal Accumulation

Effects of heavy metals on plants result in growth inhibition, structure damage, a decline of physiological and biochemical activities as well as of the function of plants. The effects and bioavailability of heavy metals depend on many factors, such as environmental conditions, pH, and species of element, organic substances of the media and fertilization, plant species. But, there are also studies on plant resistance mechanisms to protect plants against the toxic effects of heavy metals. The microorganisms act in synergism with the plants for effective phytoremediation. This synergistic relationship promotes the exchange of water and nutrients established between plant roots and specialized soil microorganisms thus, enhancing the plant growth. The application of microorganisms in phytoremediation helps to improve plant growth and survival rate. The microbial activity in the contaminated site acts as an indicator for the plant growth and bioremediation. So an attempt were made on the toxic effects of chromium in paddy plants growth and yield and thereby mitigating its toxicity by using microbial inoculants especially Azospirillum.