. Fig. 32.—Net blotch of barley. The outstanding characteristic of net blotch is a netted appearance in the spots, due to uneven distribution of brown color. yellow edges, and the leaf tissue surrounding them is often some- what yellowish. Streaks caused by this disease can be distin- guished from those of the stripe disease, since the former are much shorter and the leaf tissue does not split or shred along them. At harvest the straw of diseased plants is dull brown and weak. Infected kernels bear dark spots at the base. Life History.—The net blotch fungus produces both winter and summer spor
. Fig. 32.—Net blotch of barley. The outstanding characteristic of net blotch is a netted appearance in the spots, due to uneven distribution of brown color. yellow edges, and the leaf tissue surrounding them is often some- what yellowish. Streaks caused by this disease can be distin- guished from those of the stripe disease, since the former are much shorter and the leaf tissue does not split or shred along them. At harvest the straw of diseased plants is dull brown and weak. Infected kernels bear dark spots at the base. Life History.—The net blotch fungus produces both winter and summer spores. The summer spores are borne in abundance on the surface of leaf spots, where they may be seen as a grayish powder. Scattered by wind, water and other means, they infect leaves and plants. Successive crops of spores are formed during the growing season. Those spores falling upon the chaff may germinate and infect the grain. Once the fungus gets into the hull, it remains dormant throughout the season but renews its growth when the seed is sown. This results in direct infection of the seedling and the formation of spots on seedling leaves. The winter spores are produced in very small, dark, flattened.
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Keywords: ., bookcentury1900, bookcolle, bookpublisherurbana, booksubjectgrain
