Spot blotch is a disease of barley caused by Cochliobolus sativus. The disease is found everywhere that barley is grown, but only causes significant yield losses in warm, humid climates.[1][2]
Infections appear as dark, chocolate-colored blotches. The spots merge, eventually forming irregular necrotic patches on the leaves. Leaf spots may be surrounded by a zone of yellow leaf tissue of varying width. Spot may also appear on the leaf sheaths, necks and heads of the plant. Heavily infected leaves dry up completely, and infections on the flag leaf during kernel filling are the most serious.
Disease cycleedit
The fungus overwinters in barley straw and stubble, in the soil, or on the seed. Spores are produced on barley debris in the spring and are dispersed by wind and rain. Barley seedlings may become infected from inoculum on the seed or in the soil.
Temperatures above 20°C and moist humid conditions within the crop canopy favour spot blotch development. Conducive weather conditions may favour successive production of new spores and lesions leading to rapid disease development during the growing season.
Yield lossedit
The disease may be particularly damaging in the Upper Midwest of the United States. Yield losses of 10-30% may be occur when weather conditions are conducive to disease development.[1]
Managementedit
The disease is managed by using resistant varieties, clean seed, seed treatments, foliar fungicide and rotation to non-cereal crops.
External linksedit
Extension publicationsedit
Spot blotch (Canada: Alberta) 2015-03-27 at the Wayback Machine
^ ab Mathre, D.E. (1997). Compendium of barley diseases. American Phytopathological Society. pp. 120 pp. ISBN0-89054-180-9.
^ Martens, J.W.; W.L. Seaman; T.G. Atkinson (1984). Diseases of field crops in Canada. Canadian Phytopathological Society. pp. 160 pp. ISBN0-9691627-0-7.
February 15, 2024
spot, blotch, barley, spot, blotch, disease, barley, caused, cochliobolus, sativus, disease, found, everywhere, that, barley, grown, only, causes, significant, yield, losses, warm, humid, climates, spot, blotchcausal, agentscochliobolus, sativushostsbarleyeppo. Spot blotch is a disease of barley caused by Cochliobolus sativus The disease is found everywhere that barley is grown but only causes significant yield losses in warm humid climates 1 2 Spot blotchCausal agentsCochliobolus sativusHostsBarleyEPPO CodeCOCHSA Contents 1 Symptoms 2 Disease cycle 3 Yield loss 4 Management 5 External links 5 1 Extension publications 6 ReferencesSymptoms editInfections appear as dark chocolate colored blotches The spots merge eventually forming irregular necrotic patches on the leaves Leaf spots may be surrounded by a zone of yellow leaf tissue of varying width Spot may also appear on the leaf sheaths necks and heads of the plant Heavily infected leaves dry up completely and infections on the flag leaf during kernel filling are the most serious Disease cycle editThe fungus overwinters in barley straw and stubble in the soil or on the seed Spores are produced on barley debris in the spring and are dispersed by wind and rain Barley seedlings may become infected from inoculum on the seed or in the soil Temperatures above 20 C and moist humid conditions within the crop canopy favour spot blotch development Conducive weather conditions may favour successive production of new spores and lesions leading to rapid disease development during the growing season Yield loss editThe disease may be particularly damaging in the Upper Midwest of the United States Yield losses of 10 30 may be occur when weather conditions are conducive to disease development 1 Management editThe disease is managed by using resistant varieties clean seed seed treatments foliar fungicide and rotation to non cereal crops External links editExtension publications edit Spot blotch Canada Alberta Archived 2015 03 27 at the Wayback Machine Spot blotch Denmark Spot blotch US North Dakota Spot blotch US Oregon permanent dead link References edit a b Mathre D E 1997 Compendium of barley diseases American Phytopathological Society pp 120 pp ISBN 0 89054 180 9 Martens J W W L Seaman T G Atkinson 1984 Diseases of field crops in Canada Canadian Phytopathological Society pp 160 pp ISBN 0 9691627 0 7 Retrieved from https en wikipedia org w index php title Spot blotch barley amp oldid 1178728740, wikipedia, wiki, book, books, library,
