HYPERACCUMULATIVE POTENTIAL AND DNA PROFILING OF EICHHORNIA CRASSIPES FOR TOXICANTS IN SELECTED POLLUTED WATER BODIES

Hyperaccumulator plants are herbaceous or woody plants that can tolerate and accumulate high concentrations of heavy metals without any visible symptoms of damage. In this study, hyperaccumulative ability of Eichhornia crassipes for pollutants was evaluated. The study also aimed to determine whether pollution can negatively impact the genetic makeup of the plant. Water hyacinth samples were collected from National Horticultural Research Institute (NIHORT) and University of Ibadan (UI) in Oyo State and the Ogun River at Kara cattle market, Ojodu-Berger, Lagos State, in the months of April and June of 2021. Pollution status for the water samples collected was determined after analysing physicochemical parameters and calculating the water quality index (WQI). Heavy metal and Organochlorine pesticide analyses were done using ICP-OES and GC-MS respectively. Phylogenetic analysis was done using the Geneious prime software. Water quality indices revealed that water samples from NIHORT were the most polluted followed by Berger then UI. Accumulation of metals by the plants was in the order of Zn >Fe >Cd >Hg >Mn >Cr >Cu >Pb >Ni >As. The study revealed that the concentrations of some OCPs such as Isodrin, Endrin aldehyde and Endrin ketone were detected across the three sampling locations and were higher in the plant than in the water samples. Five OCP components namely a-Chlordane, p,p'-DDD, cis-Nonachlor, Endosulphan sulphate and beta.lindane were not detected at all. The molecular analysis produced a phylogenetic tree with three clusters and one outlier, this suggests a monophyletic origin of the plant collected. The phylogenetic analysis showed that there was no difference in the genetic profile of the plant across the sampling location. This study revealed that Eichhornia crassipes despite being a menace in the aquatic environment is useful as a phytoremediator plant in water bodies polluted with heavy metals and OCPs