Chlorinated solvents are common contaminants in soil and water. Under anaerobic conditions microbes are capable of transforming chlorinated solvents into Ethylene which would result in a remediation of the contaminated area. In order to use natural attenuation as a remediation method evidence of continuous degradation is required. Furthermore, the degradation must occur at a sufficient rate and continuous monitoring of the site is needed until the demanded levels are achieved. A field study was performed on the basis of data from a dry-cleaning facility contaminated mainly by perchloroEthylene.

This study has focused on testing the following two hypotheses:? Pest resistant plants have higher levels and/or several different kinds of secondary metabolites. ? Induced defensive systems in resistant plants are activated more rapidly than those of susceptible plants. As a background for the test of the hypotheses a short literature study was performed concerning plant defensive mechanisms in Arabidopsis thaliana.