Accumulation of potentially toxic elements in cockscomb (Celosia argentea Linn) grown in soil amended with chicken manure

Chicken manure soil amendment is an integral part of crop production that supplies nutrients for optimum crop growth but increases potentially toxic element (PTE) contaminants in soil and harvested crop. This study investigated the influence of two sources of chicken manure amendments on PTE load of soil and its bioaccumulation in cockscomb (Celosia argentea Linn). Contamination factor (CF), degree of contamination (DC), elemental pollution index (EPI) and pollution load index (PLI) were used to assess soil PTE load, while phytoextraction potential of cockscomb was evaluated using bioconcentration factor (BCF), bioaccumulation coefficient (BAC) and translocation factor (TF). Thirty potted soil, 5 kg each were amended with either commercial chicken manure (CCM) or free-range chicken manure (FCM) at rates of 4 (11.39 g), 6 (17.08 g), 8 (22.77 g), and 10 (28.46 g) t ha−1, and compared with no amendment. Treatments were replicated thrice in a completely randomized design. PTE concentrations were determined in plant and soil after harvesting at 6 weeks following standard procedures. Results show that soil pollution by PTE increased with amendments and were higher (p ≤ 0.05) in soil amended with CCM compared to FCM. CF and PLI enhanced effective cation exchange capacity by 92.7%. Root to shoot translocation of PTE was restricted by amendments. Bioaccumulation coefficient, BCF and TF were higher in cockscomb grown with CCM. Phytoextraction of copper (Cu) was higher than manganese (Mn). Potential risks of Cu and Mn accumulation are eminent in edible shoot of cockscomb above 6 t ha−1 of the amendments.