Abstract
To establish an efficient, high-throughput screening/evaluation method for mutants for defense signaling in A. thaliana, we first studied the ROS generation induced by chitin oligosaccharide elicitor in Arabidopsis. By using 96-well microtiter plates and young seedlings, we could analyze the ROS generation quite efficiently on a single plant base and also recover the plants for further cultivation and analyses. Chitin oligosaccharide elicitors induced ROS generation in a size and dose dependent manner as similar to those observed in cultured rice cells. Interestingly, ROS generation was mostly confined in the roots of the seedlings, whereas the expression of typical defense genes were observed in both roots and leaves of the chitin-treated seedlings. Pharamacological studies indicated the involvement of protein phosphorylation and NADPH-oxidase in the ROS generation. The advantage of the experimental system for dissecting plant defence signaling and screening of new mutants for chitin responsiveness will be discussed.
