Comparative analysis of heavy metals concentration in soil and vegetable (Solanum lycopersicum) collected from two sampling sites (Farmland and Dumpsite) and the effect on plant DNA

Abstract

One of the most popular crops with a unique role in human diets especially in Nigeria is Solanum Lycopersicum. The study investigated the levels of heavy metals (cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb)and zinc(Zn) and nutrients(nitrogen (N), phosphorus(P) and potassium(K) in the leaf, stem and root of Solanum lycopersicum and soil collected from dumpsite (in Ojota) and Farmland (in Badagry) in Lagos, Nigeria and their effects on S. lycopersicum using DNA analysis. The results recorded in mg/100g showed that only the value of Zn in stem of S. lycopersicum from farmland (77.671 ± 2.193) was significantly higher than that of dumpsite (72.169 ± 1.656) while Zn in the root S. lycopersicum from farmland (66.556 ± 0.613) was significantly lower than that of dumpsite (71.760±2.699). The values of K in the stem and root, P in the leaf, and N in the stem and root were higher in samples from farmland, while samples from dumpsite had higher value of N in leaf, P in stem and root and K in leaf. Only, Zn in the soil was significantly higher (p<0.05) at dumpsite than farmland. The values of N, P and K in soil from dumpsite were higher (p<0.05) than that from farmland. The DNA bands of the Solanum lycopersicum from control site and dumpsite site have no alteration. In conclusion, all the metal levels did not exceed World Health Organization limits and thus S. lycopersicum is safe for human consumption.