Ameliorative Effects of Poultry Manure on Cadmium Toxicity to Maize (Zea Mays)

Abstract

Plant uptake is one of the major pathways by which cadmium (Cd) in the soil enters the human food chain. This study was conducted to investigate the effects of poultry manure on cadmium uptake by maize. A pot experiment was conducted for nine weeks using soil samples amended with constant quantity of poultry manure (5 tons per hectare) and cadmium was applied at 0, 10, 20, 50 and 100 mg Cd kg^-1. Each rate was applied to the soils with and without poultry manure amendment. Results showed that the addition of poultry manure (PM) to the Cd polluted soil increased the height of maize particularly at 8 and 9 weeks after planting. The increment in maize shoot dry weight due PM addition were by 59 %, 19.25 % and 11.92 % at 50 mg Cd kg^-1, 20 mg Cd kg^-1 and 10 mg Cd kg^-1 respectively. The study also showed that maize grown in soil polluted with 100 mg Cd kg^-1, 50 mg Cd kg^-1 and 20 mg Cd kg^-1, but amended with PM at 5 t ha^-1 resulted in 10.43 %, 32.72 % and 125.94 % reduction in Cd uptake. There was also positive and significant correlation between maize Cd uptake and K uptake (r = 0.48 p < 0.01) and residual Cd in soil (r = 0.42 p < 0.01).