. Carnegie Institution of Washington publication. cobb's disease op sugar-cane. 23 tip on the other side. The midrib is bright green the whole length. The needle-punctures were made about a foot from the leaf-sheath. Secondary signs are visible on three of the upper leaves of this plant as long yellowish stripes, interrupted in one of the leaves. In places on one leaf the stripe is dead and reddish-brown for a distance of 8 inches and a breadth of one-sixteenth to one-eighth inch. On another there is a marginal dead stripe 2 feet long. (3) Leaf j a is dead entirely from the tip down for a dist
. Carnegie Institution of Washington publication. cobb's disease op sugar-cane. 23 tip on the other side. The midrib is bright green the whole length. The needle-punctures were made about a foot from the leaf-sheath. Secondary signs are visible on three of the upper leaves of this plant as long yellowish stripes, interrupted in one of the leaves. In places on one leaf the stripe is dead and reddish-brown for a distance of 8 inches and a breadth of one-sixteenth to one-eighth inch. On another there is a marginal dead stripe 2 feet long. (3) Leaf j a is dead entirely from the tip down for a distance of 3 feet, and the rest of the way it is dead on the margins, but the midrib is green. It was pricked about 18 inches from the top of the leaf-sheath. The leaf-sheath itself is about a foot long. Leaf 3 b is dead at the tip and down for a distance of 3 feet and the midrib is dead a foot farther down, but the margins are green. In the lowest foot both midrib and margins seem to be normal. There are no secondary signs on this plant, which is 6 feet tall and bears 13 leaves. (4) Leaf 4 a is dead from the apex down a distance of about 3 feet, while for an additional 2 feet it is dead on the margins but green in the midrib. Punctures made about 9 inches from leaf-sheath. Leaf-sheath is about 9 inches long. Leaf 4 b is dead from the apex down a distance of about 4 feet. A foot farther down it joins the stem. The lowest foot of the leaf is dead on both margins but green in the midrib. The plant itself is about 5 feet high and shows conspicuous secondary signs; 18 inches from the ground the diameter of the stem, including the leaf-sheaths, is about half an inch. It bears 12 leaves. Two of the upper leaves are dead almost all the way down and two more show brown striping on one side. The upper two are flabby. Plant brought in and photographed. It is the larger of the two of this date. Bad. vaseularum was plated from the stem of this plant. A white gas-forming organism was also obta
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Keywords: ., bookauthorcarnegie, bookcentury1900, bookdecade1910, bookyear1914
