Proteinaceous Metabolites from Pyrenophora teres Contribute to Symptom Development of Barley Net Blotch

• Published in: Phytopathology Vol. 97; no. 8; pp. 907 - 915
• Main Authors: Sarpeleh, A, Wallwork, H, Catcheside, D.E.A, Tate, M.E, Able, A.J
• Format: Journal Article
• Language: English
• Published: St. Paul, MN American Phytopathological Society 01.08.2007
• Subjects: barley; Biological and medical sciences; chlorosis; cultivars; Fundamental and applied biological sciences. Psychology; fungal diseases of plants; Fungal plant pathogens; genetic variation; Hordeum vulgare; leaves; metabolites; necrosis; pathogenesis-related proteins; pathogenicity; Phytopathology. Animal pests. Plant and forest protection; phytotoxins; plant pathogenic fungi; protein metabolism; Pyrenophora teres; Pyrenophora teres f. sp. maculata; Pyrenophora teres f. sp. teres; signs and symptoms (plants); Disease development; Monocotyledones; Plant pathology; Hordeum vulgare; Microbiology; Plant pathogen; Enzyme; Metabolite; Pyrenophora teres; Cereal crop; Protein; Fungi; Peptidases; Gramineae; Angiospermae; Hydrolases; Ascomycetes; Spermatophyta; Oxidoreductases; Lesion; Glycine dehydrogenase (decarboxylating); Thallophyta; Cultivar
• ISSN: 0031-949X; 1943-7684
• DOI: 10.1094/PHYTO-97-8-0907

Pyrenophora teres, the causal agent of net blotch of barley (Hordeum vulgare L.), induces a combination of necrosis and extensive chlorosis in susceptible barley cultivars. Cell-free filtrates from both net and spot forms of P. teres; P. teres f. sp. teres, and P. teres f. sp. maculata were found to contain phytotoxic low molecular weight compounds (LMWCs) and proteinaceous metabolites which appear to be responsible for different components of the symptoms induced by the two forms of the pathogen in a susceptible cultivar of barley (cv. Sloop). Proteins induced only brown necrotic spots or lesions similar to those induced by the pathogens 72 h after inoculation. In contrast, LMWCs induced general chlorosis seen 240 h after inoculation but not the localized necrosis. Neither hydrolyzed or heat- or protease-treated proteinaceous metabolites induced the symptoms. This is the first report of the involvement of proteins produced by P. teres in symptom development during net blotch disease of barley.