Biological Materials: Alyssum lesbiacum 4

by Kat Smart

Description of Image: Metal-contaminated soils and water pose a major environmental and human health problem, which may be partially solved by the use of green plants to remove pollutants from the environment. This emerging technology is known as phytoremediation. Its development has been driven by the prohibitively high cost of present soil remediation methods. A more cost-effective plant-based approach to remediation takes advantage of the remarkable ability of a particular species of plant, known as metal hyperaccumulators, to acquire extraordinary concentrations (5% to 3% dry biomass) of certain metals in their stems and leaves without any signs of toxicity to the plant. This project is concerned with using high resolution analysis techniques to investigate the metal ion distribution in the nickel hyperaccumulating plant Alyssum lesbiacum. A considerable fraction of the nickel accumulates in the peripheral cells of the shoot, and nickel may reach very high concentrations in the epidermal hairs, know as trichomes, which are beautiful unicellular stellate structures that cover the surface of species such as Alyssum lesbiacum and give the shoot surface a silvery-whitish appearance. The image shows a scanning electron microscope photograph of the surface of Alyssum lesbiacum prepared in this project for analysis by the sputtering of a thin layer of gold.