Experimental Procedure: Plastic pots 20 cm diameter and height were filled with 2kg of 2mm sieved dry soil
The soils were artificially polluted using potassium dichromate (K2Cr2O7) and biochar produced from maize stalk was
applied at the rates of 0, 5t/ha and 10t/ha. According to Abdul [18], applications of chromium up to 5ppm had nominal effect on plants, while there was no plant survival beyond 40 ppm. Therefore, Cr levels selected for this study were 0(control), 10ppm and 20ppm. The pots were then arranged in complete randomized design and replicated three times. Four lettuce (Lactuca sativa) seeds were sown in each pot and after germination only one plant was retained in each pot until flowering.
The plants procedure of SAS 9.2. Means separation was done using least significant difference (LSD) after the treatments were found significant at P