Phyto-Tolerance Degradation of Hydrocarbons and Accumulation of Heavy Metals by of Cajanus cajan (Pigeon Pea) in Petroleum-Oily-Sludge-Contaminated Soil

A pot experiment was conducted to measure the phyto-tolerance and accumulation of heavy metals in petroleum oily sludge POS by Cajanus cajan (pigeon pea) on soils treated with five different concentrations (1%, 2%, 3%, 4%, 5% w/w) POS. The response plant varied significantly from untreated control among various treatments. growth C. slightly (but not significantly) influenced soil; at relatively lower (1 3%) greater than treatments higher (4 5%). significant interaction observed relative rates (RGRs) cajan, which increased low decrease concentrations. metal content roots as were increase show that concentration all accordingly. Cu showed highest an 1.9 6.8 mg/kg followed Pb, Zn, Ni, Mn, Cr, least-accumulated. Heavy analysis tissues indicated a considerable Cu, Cr root stem plant, negligible detected leaves, suggesting translocation factor but indicating is resistant metals. As search for more eco-friendly sustainable remediating green continues, shows great potential reclaiming POS-contaminated soil due above properties including resistance toxic sludge. These findings will provide solutions polluted their subsequent re-vegetation.