| Autor: |
E. Bresson, Jean-Paul Geiger, Jean-François Daniel, Michel Nicole, C. Andary, G.H. Dai, Bernard Boher, Christelle Martinez |
| Rok vydání: |
1996 |
| Předmět: |
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| Zdroj: |
Physiological and Molecular Plant Pathology. 49:285-306 |
| ISSN: |
0885-5765 |
| DOI: |
10.1006/pmpp.1996.0055 |
| Popis: |
Interactions between cotton cotyledons and Xanthomonas campestris pv. malvacearum were examined. During an incompatible interaction, fluorescence microscopy revealed that flavonoid compounds accumulated within 10 h after inoculation. Electron micrographs showed ultrastructural modifications of cells that exhibited an intense fluorescence suggesting the presence of flavonoids. Phenol-like molecules were produced by cells of infection sites and were found in paramural areas within papillae enriched with callose and in host cell walls and middle lamellae. Histochemistry showed that peroxidase activity and terpenoids were detected in the infected resistant plants, 4 and 48 h after inoculation, respectively. In contrast, no changes in the deposits of lignin, suberin, and catechin were seen in either the infected susceptible or resistant lines. We suggest that early flavonoid accumulation is associated with the hypersensitive reaction of cotton cotyledons to X. campestris pv. malvacearum. The activity of wall-bound peroxidases may play a role in the incorporation of flavonoids in cell walls and paramural papillae. O 1996 Academic Press Limited INTRO D UCTlO N Bacterial blight caused by Xanthomonas campestris pv. malvacearum (Smith) -Dye (Xcm) is a widespread and destructive disease of cotton (Gossypium spp.) in ‘almost every - country in the world where this plant grows. Yield losses from severe infection can reach 70 yo during epidemics in Africa. Angular leaf spot, blackarm and bacterial boll rot are names given to the various stages in the syndrome [31]. Considerable variation in resistance to blight occurs in the genus Gossypium [8], but the highest degree of i |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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