Effect of Sewage Sludge and Fertilizers Application on Accumulation of Heavy Metals and Yield of Rice (Oryza sativa L.) in an Inceptisol of Varanasi

Abstract

A greenhouse study was conducted during July to October 2009 to find out the effect of conjoint applicationof sewage sludge and fertilizers on yield and heavy metals accumulation in rice. Five doses of sewagesludge as 0, 10, 20, 30 and 40 t ha-1 were applied along with five levels of recommended dose of fertilizer(RDF as 0, 25, 50, 75 and 100%). Results of this study showed a significant increase in test weight andgrain and straw yield. However, the values for harvest index were non-significant for different doses ofsewage sludge. About 33 and 46% increase in grain yield was observed over control in the treatmentswhere 100% RDF without sludge and 40 t ha-1 sewage sludge without RDF was applied, respectively.Highest grain yield was recorded in the treatment where 40 t ha-1 sewage sludge was applied along with100% RDF. Application of sewage sludge along with fertilizers also increased Ni, Cr, Cd and Pb content inrice straw and grain. It was about 7, 5, 5 and 10 times increase in Cd, Cr, Ni and Pb content, respectively inrice grain and about 7, 3, 7 and 2 times increase in rice straw over their control.