Metal Concentration in Plant Tissues of Ricinus communis L. (Castor Oil) Grown In Soil Contaminated With Spent Lubricating Oil

Castor oil plant seeds ( Ricinus communis L.) were grown in spent lubricating oil (SLO) contaminated soil at concentrations of 1-6% (w/w, oil/soil). Plant height and stem girth were depressed by spent lubricating oil at concentrations of 2% (w/w) and above. One percent (1%) spent lubricating oil in soil promoted growth of plants when compared with control. Fresh and dry weights of R. communis plants grown in 1% oil treatment were significantly more than that of control. Spent lubricating oil in soil depressed pH. From the values obtained for metal concentrations in leaves, stems and roots, the concentrations of manganese and nickel were highest in the leaves. At 2% SLO and above, lead concentration was highest in the leaves too. Accumulation of the metals by plant parts were not concentration dependent. Specifically metal accumulation in R. communis, in the present study showed that Mn , Ni and Pb were mostly accumulated in the leaves; while V was highest in roots

Growth Response of Ricinus communis L (Castor Oil) in Spent Lubricating Oil Polluted Soil

The growth response of castor oil plant, Ricinus communis , in spent lubricating oil (SLO) was investigated using 1-6% w/w SLO and a control. The result showed that highest percent germination of approximately 92, was obtained in control and the least in 5% w/w. The early germination obtained in this study was significant when considered in the light of reported delay and depression of germination by spent lubricating oil in Capsicum annum , Lycopersicon esculentum , Solanum melongena and S. incanum. For parameters like plant height, stem girth, leaf area, fresh and dry weights, and root length, the mean values obtained were higher for 1% w/w than control. There was stimulation of growth at 1% w/w spent lubricating oil in soil. Plants in higher concentration (2 - 6% w/w) exhibited depression in growth. Plants grown in 1% w/w spent lubricating oil in soil flowered earlier than those grown in control. A difference of eight (8) days was observed. @JASE

Growth Response of Ricinus communis L (Castor Oil) in Spent Lubricating Oil Polluted Soil

The growth response of castor oil plant, Ricinus communis , in spent lubricating oil (SLO) was investigated using 1-6% w/w SLO and a control. The result showed that highest percent germination of approximately 92, was obtained in control and the least in 5% w/w. The early germination obtained in this study was significant when considered in the light of reported delay and depression of germination by spent lubricating oil in Capsicum annum , Lycopersicon esculentum , Solanum melongena and S. incanum. For parameters like plant height, stem girth, leaf area, fresh and dry weights, and root length, the mean values obtained were higher for 1% w/w than control. There was stimulation of growth at 1% w/w spent lubricating oil in soil. Plants in higher concentration (2 - 6% w/w) exhibited depression in growth. Plants grown in 1% w/w spent lubricating oil in soil flowered earlier than those grown in control. A difference of eight (8) days was observed. @JASE

Sodium Azide Priming Enhances Waterlogging Stress Tolerance in Okra (Abelmoschus esculentus L.)

Waterlogging stress adversely affects crop growth and yield worldwide. Effect of sodium azide priming on waterlogging stress tolerance of okra plants was investigated. The study was conducted as a field experiment using two weeks old plants grown from 0%, 0.02%, and 0.05% sodium azide (NaN3)-treated seeds. The waterlogging conditions applied were categorized into control, one week, and two weeks. Different growth and reproductive parameters were investigated. Activity and expression of antioxidant enzymes, root anatomy, and soil chemical analysis were also studied. Results showed that sodium azide priming inhibited germination. The germination percentages recorded were 92.50, 85.00, and 65.00 for 0%, 0.02%, and 0.05% NaN3-treated seeds, respectively, nine days after planting. Waterlogging conditions depressed plant height ten weeks after planting. Under waterlogging conditions, NaN3 promoted plant height and number of leaves formed. NaN3 also supported the survival of plants and formation of adventitious roots under waterlogging conditions. Waterlogging conditions negatively affected the redox potential, organic C, N, and P concentrations in the soil but enhanced Soil pH, Fe, Mn, Zn, and SO4. Under waterlogging conditions, NaN3 increased the average number of flower buds, flowers, and fruits produced in comparison to control. Moreover, NaN3 highly stimulated the development of aerenchyma which in turn enhanced the survival of okra plants under waterlogging conditions. NaN3 priming also enhanced the activities and gene expression level of antioxidant enzymes (ascorbate peroxidase, APX; catalase, CAT) under waterlogging conditions. In conclusion, this study demonstrated that NaN3 priming could improve waterlogging stress tolerance in okra