This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Journal of Experimental Botany, Vol. 58, No. 4, pp. 797–806, 2007 Imaging Stress Responses in Plants Special Issue doi:10.1093/jxb/erl208 Advance Access publication 30 November, 2006 SPECIAL ISSUE PAPER Visualization of dynamics of plant–pathogen interaction by novel combination of chlorophyll ﬂuorescence imaging and statistical analysis: differential effects of virulent and avirulent strains of P. syringae and of oxylipins on A. thaliana Susanne Berger 1, *, Zuzana Benediktyova ´ 2,3, * ,† , Karel Matous ˇ 2,3 , Katharina Bonfig 1 , Martin J. Mueller 1 , Ladislav Nedbal 2,3 and Thomas Roitsch 1 1 Julius-von-Sachs-Institute of Biosciences, Department of Pharmaceutical Biology, Julius-von-Sachs-Platz 2, D-97082 Wu¨rzburg, Germany 2 Institute of Systems Biology and Ecology, Academy of Sciences of the Czech Republic 3 Institute of Physical Biology, University of S. Bohemia, Za´mek 136, 37333 Nove´ Hrady, Czech Republic Received 7 May 2006; Accepted 20 September 2006 Abstract Pathogen infection leads to defence induction as well as to changes in carbohydrate metabolism of plants. Salicylic acid and oxylipins are involved in the induction of defence, but it is not known if these signalling molecules also mediate changes in carbohydrate me- tabolism. In this study, the effect of application of salicylic acid and the oxylipins 12-oxo-phytodienoic acid (OPDA) and jasmonic acid on photosynthesis was investigated by kinetic chlorophyll ﬂuorescence imag- ing and compared with the effects of infection by virulent and avirulent strains of Pseudomonas syringae . Both pathogen strains and OPDA caused a similar change in ﬂuorescence parameters of leaves of Arabi- dopsis thaliana . The response to OPDA appeared faster compared with that to the pathogens and persisted only for a short time. Infiltration with jasmonic acid or salicylic acid did not lead to a localized and distinct ﬂuorescence response of the plant. To capture the faint early symptoms of the plant response, a novel algo- rithm was applied identifying the unique ﬂuorescence signature—the set of images that, when combined, yield the highest contrast between control and infected leaf segments. Unlike conventional ﬂuorescence parame- ters, this non-biased approach indeed detected the infection as early as 6 h after inoculation with bacteria. It was posssible to identify distinct ﬂuorescence signa- tures characterizing the early and late phases of the infection. Fluorescence signatures of both infection phases were found in leaves infiltrated with OPDA. Key words: Biotic stress, chlorophyll ﬂuorescence, com- binatorial ﬂuorescence imaging, harmonically forced oscilla- tions, jasmonic acid, OPDA, photosynthesis, salicylic acid....
View Full Document
This note was uploaded on 05/28/2010 for the course WE BIOL000000 taught by Professor Laurychaerle during the Spring '10 term at Ghent University.
- Spring '10