Document Detail
Early defence responses of cowpea (Vigna sinensis L.) induced by non-pathogenic rust fungi
Abstract/OtherAbstract :
In cowpea (Vigna s&ensis L.) leaves the pathogenic rust fungus Uromyces vignae and the non-pathogens U. appendiculatus and U. viciae-fabae developed similarly to give rise to more than 80% haustorial mother cells. Whereas U. vignae was able to sporulate, the nonpathogens were stopped either after formation of some haustoria (U. appendiculatus) or immediately after formation of haustorial mother cells (U. viciae-fabae). Approximately 30% of the cells in contact with haustorial mother cells of the two non-pathogens showed autofluorescence and deposition of phloroglucinol/HC1- positive material. The early defence reactions of V. sinensis include induction of phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) and extracellular peroxidase (POD, EC 1.11.1.7) activity as early as 10h and 24h after inoculation, respectively. Probing Western blots with heterologous monospecific anti-PAL serum showed that pathogenesis-induced increases in enzyme activity are the result of de novo synthesis. Native polyacrylamide gel electrophoresis revealed the specific induction of two extracellular acidic POD forms in cowpea inoculated with the non-pathogens. Both PAL and apoplasmic POD activities were highest in U. viciae-fabae-, intermediate in U. appendiculatus- and low in U. vignae-inoculated or talcum-treated control plants. The timing of increasing PAL and extracellular POD activities in relation to deposition of lignin or lignin-like material in mesophyll cell walls indicates the involvement of lignification in the early defence of V. sinensis against biotrophic fungal parasites. Analysis of the substrate specificity of the inducible POD forms, separated and partially purified by chromatofocusing, showed that apoplasmic PODs preferentially oxidize the naturally occurring substrate coniferyl alcohol. These results support the assumption that POD-mediated lignification is involved in the expression of non-host resistance of cowpea to rust fungi.
Authors :
Fink, Werner, Haug, M., Deising, Holger, Mendgen, Kurt
Related Documents :
9781757 - Viability of indigenous soil bacteria assayed by respiratory activity and growth
33368307 - The phagocytic power of connective tissue cells
8783337 - Cell, vol. 115, 333--342, october 31, 2003, copyright 2003 by cell press
8004777 - Automatic layout of domain-specific reconfigurable
6476867 - Simplified module assembly using back-contact crystalline-silicon solar cells
Contributors :
-
Publication Detail :
Publisher :  Universität Konstanz, Fachbereich Biologie. Fachbereich Biologie     Type :  Article     Format :  application/pdf    
Date Detail :
1991
Subject :
Defense response to non-pathogens, Lignification, Non-host resistance, Peroxidase (extracellular), Phenylalanine ammonia-lyase, Rust fungi, Vign, Life sciences
Coverage :
-
Relation :
-
Source :
First publ. in: Planta 185 (1991), pp. 246-254
Copyright Information :
http://creativecommons.org/licenses/by-nc-nd/2.0/de/deed.de
Other Details :
Languages :  eng    
Export Citation :
APA/MLA Format     Download EndNote     Download BibTex

Previous Document:  The haustorial host-parasite interface in rust-infected bean leaves after high-pressure freezing
Next Document:  Rapid site-directed domain scanning mutagenesis of enteropathogenic Escherichia coli espD