. Diseases of economic plants. Plant diseases. FOBAGE CROPS 391 a faint reddish brown tinge. After the leaves have fallen the stem dies and becomes covered with a light pink coat- ing of the spores of the wilt fungus. The spread of the disease is more gradual and less conspicuous in the early part of the season, but after the peas begin to set fruit they succumb rapidly, and a jfield that in July ma\^ promise a fine crop may be entirely dead before September without hav- ing matured a pod. ' The disease usually appears in spots, like the cotton wilt, and these diseased areas spread until they
. Diseases of economic plants. Plant diseases. FOBAGE CROPS 391 a faint reddish brown tinge. After the leaves have fallen the stem dies and becomes covered with a light pink coat- ing of the spores of the wilt fungus. The spread of the disease is more gradual and less conspicuous in the early part of the season, but after the peas begin to set fruit they succumb rapidly, and a jfield that in July ma\^ promise a fine crop may be entirely dead before September without hav- ing matured a pod. ' The disease usually appears in spots, like the cotton wilt, and these diseased areas spread until they may cover a whole field. In moderate cases, or where the varieties planted are less subject to the disease, only the weaker plants are killed, while the rest are dwarfed and their yield reduced. Careful examination of the roots shows that many of the small lateral roots are dead, small roots marking the points of infection. Fig. 168. This tufting of the rootlets is similar to that produced on cotton by the cotton wilt fungus. In all cases the veins of the stem are brown, and the dis-. FiG. 168. — Roots of diseased cowpea at left; healthy roots on the right. After Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Stevens, Frank Lincoln, 1871-1934; Hall, John Galentine, 1870-. New York, Macmillan
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Keywords: ., bookauthorstevensf, bookcentury1900, bookdecade1910, bookyear1910
