Journal article

Publication year: 1994

Pages: 1269-1277

Journal: Plant Physiology

Volume number: 106

Issue number: 4

ISSN: 0032-0889

eISSN: 1532-2548

DOI Link: https://doi.org/10.1104/pp.106.4.1269

Publisher: Oxford University Press

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 Mlg 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.

Harvard Citation style: Kogel, K., Beckhove, U., Dreschers, J., Munch, S. and Romme, Y. (1994) Acquired Resistance in Barley (The Resistance Mechanism Induced by 2,6-Dichloroisonicotinic Acid Is a Phenocopy of a Genetically Based Mechanism Governing Race-Specific Powdery Mildew Resistance), Plant Physiology, 106(4), pp. 1269-1277. https://doi.org/10.1104/pp.106.4.1269

APA Citation style: Kogel, K., Beckhove, U., Dreschers, J., Munch, S., & Romme, Y. (1994). Acquired Resistance in Barley (The Resistance Mechanism Induced by 2,6-Dichloroisonicotinic Acid Is a Phenocopy of a Genetically Based Mechanism Governing Race-Specific Powdery Mildew Resistance). Plant Physiology. 106(4), 1269-1277. https://doi.org/10.1104/pp.106.4.1269