Effects of Nickel Salt Concentrations on Germination and Development of Grevillea exul var. rubiginosa

Abstract

Endemic plant species have been considered as one of the best means of ecological restoration of exploited mine sites in New Caledonia. These plants have the adaptability characteristics that allow them to thrive on serpentine soils. This study has investigated the physiological effects of nickel concentrations at different developmental stages on Grevillea exul var. rubiginosa an endemic New Caledonian species. The first two stages of a plant life cycle germination and post germination under controlled conditions were studied. The experiment involved Petri dish germination and growth of seeds and seedlings respectively particularly root development and length in different salts of nickel (acetate, chloride and sulphate) with 0­500 ppm concentrations. Decrease in both studied parameters: germination rates and root lengths were observed with increasing concentrations of nickel solutions supplied to seeds. A minimum concentration of 5 ppm of nickel in the medium had a positive effect on germination rate as well as root length. Results suggest that it is the concentration of nickel used in the present investigation to test the germination rate and root elongation in Grevillea exul var. rubiginosa which are essential for experimental work in the field rather than the form (salt) of nickel. These results will be help-full in re-vegetation efforts of nickel mining sites in New Caledonia.