Submitted to: Physiological and Molecular Plant Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/18/2009
Publication Date: 7/1/2009
Citation: Baker, C.J., Whitaker, B.D., Mock, N.M., Rice, C., Roberts, D.P., Deahl, K.L., Ueng, P.P., Aver'Yanov, A.A. 2009. Differential induction of redox sensitive extracellular phenolic amides in potato. Physiological and Molecular Plant Pathology. 73:109-115. Interpretive Summary: Plant diseases cause major losses to farmers each year. Better understanding of the biochemical basis for plant resistance to disease will lead to improved strategies to improve plant health and reduce losses. In this paper we report the identity of several bioactive chemicals that were produced by potato plant cells soon after they were inoculated with a disease-causing organism (pathogen). These chemical regulators may determine whether the potato will be resistant or susceptible. By being aware of and being able to quantify these chemical regulators we will improve our understanding of how plants and pathogens interact and we can attempt to improve plant disease resistance. This information will be of use to plant scientists who are devising new strategies to improve disease resistance in plants.
Technical Abstract: This study focuses on the differential induction of extracellular phenolic amides that accumulate in potato cell suspensions during the first few hours of the interaction between these plant cells and bacterial pathogens or pathogen-related elicitors. Using suspension cells of Solanum tuberosum we identified 4 hydroxycinnamic acid amides that accumulate in the extracellular environment. Treatment of the suspension cells with pathovars of the plant pathogens Pseudomonas syringae or Ralstonia solanacearum or with pathogen-related extracts resulted in the increased elicitation of extracellular phenolics. The composition of the elicited phenolics differed for each treatment. Some of the phenolic amides were sensitive to oxidative stress; when suspension cells were treated with bacterial strains or elicitors that triggered an oxidative burst, the phenolics were oxidized and depleted for the duration of the burst. Other critical parameters that affected the qualitative and quantitative makeup of these phenolics were plant cell age and density.