ABSTRACT:The effect of crude oil contaminated soil on the growth of seashore Paspalum ( Paspalum vaginatum .) seedlings was investigated. Plants were grown in soil containing different concentrations: 0%, 0.5%, 1.0%, 2.0% and 3% (w/w) of Abura crude petroleum oil. Growth parameter such as shoot number, shoot length, leaf area and biomass accumulation were evaluated. The results showed that crude oil imposed physiological stress in the seedlings. There was a dose response decline in all the growth attributes examined. There was also a significant difference in plant growth with respect to time of crude oil application. At the highest applied concentration(3 % [w/w]), plants grown in soil previously contaminated with petroleum oil showed about 50 % reduction in biomass accumulation when compared with the uncontaminated control whereas established plants post -treated with crude petroleum oil showed a 30% reduction. There was no mortality at any of the crude oil concentrations to which to plant was exposed. The experiment demonstrated the potential of using Paspalum vaginatum for phytoremediation. @ JASEM

Variations in 25 populations of Luffa aegyptiaca L. in southwestern Nigeria and their possible causes were studied. The variations were most pronounced in the leaf, especially in texture, invagination, area, and dry weight. Shoot and fruit dry weights also showed considerable variation. While mean seed dry weight showed remarkable constancy in the populations studied, mean seed number per fruit varied greatly.Populations growing in acid soil with low nutrient content had deep leaf invaginations, small leaf areas per shoot, and small leaf, shoot, and fruit dry weights, while populations growing in neutral or basic soils with high nutrient content had shallow leaf invaginations, large leaf area per shoot, and large leaf, shoot, and fruit dry weights.When seeds from a population with deep leaf invagination and small leaf area were grown in soil from the site of a population with shallow leaf invagination and large leaf area, the resulting plants developed the characteristics of the second population. The reciprocal procedure gave a similar result. The variations in soil were thought to be responsible for the variation noted in leaf morphology, size, and weight and for variation in shoot and fruit dry weights. Light was partially responsible for the variations in the leaf colour and in the prominence of leaf veins.

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Pot experiments were carried out to evaluate the effects of simulated acid rain (pH 5.6 (control), 5.0, 4.0, 3.0, and 2.0) exposures on Capsicum annuum L. All pH levels with the exception of the control adversely affected all growth parameters (plant height, number of leaves, fresh and dry weight of leaves, root, stem and fruits, stem girth) of the plant. Leaf area and fruit production were also impacted. Nutritional analysis of the leaves revealed a decline with increasing acidity levels. Simulated acid rain induced morphological changes such chlorosis, necrosis, early leaf senescence, leaf abscission and death. The reduction in growth parameters were concentration dependent. The most negative effects of simulated acid rain on the plant growth parameters and nutrient content analysis were observed in pH 2.0 treatment.