RESUMO
In the present study physiological, biochemical and growth characteristics of a leafy vegetable palak (Beta vulgaris L. var All green H1) grown in suburban areas irrigated by wastewater were compared with those irrigated by ground water. Continuous use of wastewater for irrigation led to the enrichment of micronutrients including heavy metals in the soil. Wastewater irrigation favorably affected the physiological, biochemical and growth characteristics of plants, but biomass and yield did not differ significantly between the sites. Uptake and translocation ratio of heavy metals were higher in plants grown at wastewater irrigated site. Mn showed maximum uptake followed by Zn, Cu, Pb, Ni Cr and Cd. Plants produced more secondary metabolites and antioxidants to tolerate against the negative impact of heavy metals at wastewater irrigated sites. Plants produced more metabolites to compensate the toxicity of metals in the area and thus did not enhance the yield and biomass potential. The study suggests that plants growing in wastewater irrigated area have potentially developed the defense strategy to combat against heavy metal toxicity.