Abstract
This paper describes an efficient evaluation system of Arabidopsis mutants for defense responses. Young A. thaliana seedlings were analyzed for the induction of reactive oxygen species (ROS) as well as defense gene expression by chitin oligosaccharide elicitor in microtiter plates. Combined with the analysis of ROS in microtiter plates, the system enabled to evaluate thousands of mutant plants within a couple of weeks. Pharmacological studies could be applied and provided information about the molecular machinery involved in the defense responses. Experiments with the dissected organs showed that the roots were responsible for most ROS generation while the gene activation was observed in all the organs. An example of the successful application of this system for the screening of Arabidopsis muntats is also presented. Thus, the system provides a promising approach to screen, or evaluate, novel mutants for a confined defense signaling cascade downstream of a specific elicitor.
