GrainGenes Reference Report: PPS-106-1269
Reference
PPS-106-1269
Title
Acquired resistance in barley. The resistance mechanisms induced by 2,6-dichloroisonicotinic acid is a phenocopy of a genetically based mechanism governing race-specific powdery mildew resistance
Journal
Plant Physiology
Year
1994
Volume
106
Pages
1269-1277
Author
Kogel K Beckhove U Dreschers J Munch S Romme Y
Abstract
Treatment of susceptible barley (Hordeum vulgare) seedlings with 2,6-dichloroisonicotinic acid (DCINA) induces disease resistance against the powdery mildew fungus (Erysiphe graminis f sp hordei) A cytological analysis of the interaction reveals the hypersensitive cell collapse in attacked, short epidermal cells, along with the accumulation of fluorescent material in papillae, that appear at the time of fungal arrest The cell-type-specific hypersensitive reaction occurs prior to formation of haustoria, reminiscent of the mechanism identified in genetically resistant barley plants containing the functionally active M/g gene (R Gorg, K Hollricher, P Schulze-Lefert [1993] Plant J 3: 857-866). This observation indicates that the mechanism of DCINA-induced resistance is a phenocopy of the mechanism governed by the Mlg locus. The onset of acquired resistance correlates with high-level transcript accumulation of barley defense-related genes encoding pathogenesis-related protein-1, peroxidase, and chitinase but not beta-1,3-glucanase. Subcellular localization of peroxidase activity shows an increase in enzyme activity in the epidermal cell layer and in the intercellular fluids of barley leaves. Four out of more than 10 identified extracellular isozymes are induced by DCINA. The epidermal cell layer contains a major constitutively formed isozyme, together with two isozymes specifically induced by DCINA. The data support the hypothesis that host cell death and high-level accumulation of defense-related gene transcripts are not only commonly controlled in certain types of race-specific resistance (A. Freialdenhoven, B. Scherag, K. Hollricher, D.B. Collinge, H. Thordal-Christensen, P. Schulze-Lefert [1994] Plant Cell 6: 983-994) but also in acquired resistance, which confers protection to a broad spectrum of different pathogens.
Keyword
3-glucanase
[ Show all 21 ]
GrainGenes is a product of the Agricultural Research Service of the US Department of Agriculture.
GrainGenes Reference Report: PPS-106-1269
|
| ||||||
|
| ||||||
|
| ||||||
|
| ||||||
|
| ||||||
|
| ||||||
|
| ||||||
|
| ||||||
|
|
GrainGenes is a product of the Agricultural Research Service of the US Department of Agriculture. | |||