Remediative Abilities Of Cowpea (Vigna Unguiculata), Bambara Groundnut (Vigna Subterranean) And Maize (Zea Mays) On Soils Polluted With Lead And Zinc

ABSTRACT Accessions Tvu 3788 and IT 99K-377-1, Tvsu 102 and Tvsu 1685 and ACR.91SUWANI-SRC1 and DMR-LSRW of Cowpea (Vigna unguiculata), Bambara groundnut (Vigna subterranean) and Maize (Zea mays) respectively were subjected to lead (Pb) and zinc (Zn) treatment and screened for their ability to tolerate these metals. Accessions Tvu 3788, Tvsu 102 and ACR.91SUWANI-SRC1 of cowpea, bambara groundnut and maize respectively were chosen and used for the experiment. The toxic effects of lead and zinc on the growth and development and biochemical activities of the three crop plants were carried out. The genotoxic effect of the heavy metals (Pb) and (Zn) on cowpea, bambara groundnut and the maize crop was investigated. The potential of cowpea, bambara groundnut and maize in the remediation of lead and zinc from polluted soils as well as the effects of Ethylenediamine tetra acetic acid (EDTA) and farmyard manure on the remediative abilities of the crop plants were also investigated. The genetic variability for lead and zinc tolerance by the crop plants were also determined. Fresh and dry weights of plants were obtained using a weighing balance and by oven-drying. The chlorophyll content was determined by spectrophotometry. Genotoxicity was determined by chromosomal squash technique with lactic acetic orcein stain. The amount of metals contained in plants’ tissues was determined by Atomic Absorption spectrophotometry. RAPD-PCR analysis for determining genetic variation of plants was also carried out. One-way ANOVA and student’s t-test using Microcal origin 5.0 software procedures were carried out on the morphological and biochemical parameters. A statistically significant difference (P