Heavy Metal Accumulation in Cockscomb (Celosia Argentea Linn) Grown in Soil Amended With Chicken Manure

Abstract

Heavy metals such as Cadmium (Cd), Copper (Cu) and Manganese (Mn) in chicken manure can contaminate soil and bioaccumulate in edible tissues of plant to cause food chain contamination. This study investigated the influence of chicken manure on heavy metal load of soil and accumulation in tissues of Celosia argentea. Air-dried chicken manure from battery cages (conventional chicken manure-CCM) and free range birds (local chicken manure-LCM) were used for the pot culture. Chicken manure was applied as amendment at the rate of 0, 4, 6, 8 and 10 t ha-1 in 5 kg soil. Treatments were replicated trice in a Completely Randomized Design. Results showed that soil metal pollution increased with rates of amendment. Metal pollution indices; contamination factor, degree of contamination, elemental pollution index, pollution load index and total contamination factor were significantly (p < 0.001) higher in soil amended with CCM than LCM. Bioaccumulation coefficients (BAC), bioaccumulation factor (BAF) and transfer factor (TF) of metals were higher in tissues of celosia grown with CCM than LCM. Furthermore, above 4 t ha-1, growth and yield were not significantly influenced by amendment rates. Mobility of metals from soil to tissues of celosia increased in the order Cu > Mn > Cd. Chicken manure above 4 t ha-1 potent health risks of Cu exposure to consumers of celosia.