EFFECTS OF ROOT EXUDATES OF VETIVER ON PHYSICOCHEMICAL PROPERTIES AND FRACTIONATION OF HEAVY METALS IN TANNERY EFFLUENT CONTAMINATED SOILP. Bhavani, K. Suganya, K. Sara Parwin Banu, A. Ramalakshmi and L. NalinaAbstract A range of organic substances, referred to as root exudates can be released by plant roots either actively or passively which are the notable source for microbial growth in the root zone and also involved in nutrient cycling and mineralisation of organics thus they could possibly influence the degradation of contaminants in the rhizosphere. The key components of the root exudates of vetiver are total carbohydrates, reducing sugars, total phenolics, flavonoids, total alkaloids, organic acids and total proteins. The organic acids are found in significantly higher amount under heavy metal stress conditions. On addition of this root exudates manually for a period of 60 days yielded in alteration in the physico-chemical properties of the soil and fractionation of chromium and lead â the representative contamiants present in the experimental soil which was collected from the tannery effluent polluted areas of Vellore, Tamil Nadu. The pH and organic carbon content in the soil is increased while the electrical conductivity got decreased. The root exudates application possibly increased the bioavailability of the heavy metals besides reducing the residual form which paves the way for easier remediation of such metals since their availability got increased. The positive effect of root exudates of vetiver provided a new idea to remediate the contaminated soils. |