ABSTRACT

This study examined the effects of used lubricating oil-polluted soil on the morphology, anatomy, growth and development of chrysopogon zizanioides and Andropogon tectorum. Top soil excavated from mechanic workshops in Ekwulobia, Aguata Local Government Area, Anambra State was used as polluted soil while soil from a farmland, l00m away was used as the control . 5kg of each were put in perforated cylindrical plastic buckets 20cm in diameter and 21cm height. Root and shoot stocks (tillers) of C.zizanioides and A. tectorum were pruned to uniform sizes of 6cm and 10cm respectively. The experimental design was completely randomized, two treatments with 10 replicates. Growth parameters were measured at 4 weeks interval for 12 weeks. Anatomical studies on the epidermis, lamina, stems and roots of the two plants were carried out using standard methods. Heavy metal analysis of the polluted and unpolluted soils and plant tissues were determined. Student t-test statistics was used for data analysis. Heavy metals such as Fe, Pb, Zn, cu etc were found in polluted, unpolluted soil and plant tissues. However, the concentrations were lower in unpolluted soils and plant tissues. Result of growth studies show that used lubricating oil- polluted soil has no significant effect on the clump size and clump height of (.zizanioides, but have significant effect on the number of tillers, leaf breadth and total bioinass (P<0.05). For A. Ieclorun the polluted soil has significant effect on all the parameters measured (P<0.05). Morphological and anatomical abberrations were observed for plants grown in polluted soil. These defects included chlorosis, reduction in plant clump size and height, number of tillers, leaf breadth size and total biomass. Anatomically, there was epidermal, cortical and vascular bundles disorganization and maceration, distortion of shape of epidermal, cortical and parenchyma cells, reduced stomata! index, larger and narrower intercellular air spaces of the cortex etc. These effects no doubt affected the physiology of the plants.