Diseases and decays of Connecticut Diseases and decays of Connecticut tobacco diseasesdecaysof00ande Year: 1940 100 Connecticut Experiment Station Bulletin 432 This is a rapid wet rot, causing all the plants in the patch to fall to the ground in a water-soaked, dark green, slimy decay, leaving the spot quite bare. On drying out, the ground is covered with a brown crust of the bleached leaves (Figure 5), Unlike the Rhizoctonia disease, this is not characterized by definite dark brown lesions on the stalk of the plant. The stalk becomes soft and watery and the bud rots out. The writer has been
Diseases and decays of Connecticut Diseases and decays of Connecticut tobacco diseasesdecaysof00ande Year: 1940 100 Connecticut Experiment Station Bulletin 432 This is a rapid wet rot, causing all the plants in the patch to fall to the ground in a water-soaked, dark green, slimy decay, leaving the spot quite bare. On drying out, the ground is covered with a brown crust of the bleached leaves (Figure 5), Unlike the Rhizoctonia disease, this is not characterized by definite dark brown lesions on the stalk of the plant. The stalk becomes soft and watery and the bud rots out. The writer has been unable to determine whether infection starts in the stalk or in the bud. A very characteristic symptom is the manner in which the light brown rot runs up the petiole into the lower part of the leaf, discoloring it in a fan- shaped area corresponding to the base of the leaf (Figure 16). Blackleg. In all cases observed here, blackleg first becomes evident when the plants are several inches tall and about ready for transplanting to the field. We have never seen it on younger plants. The first evidence of trouble which the grower notices is that patches of plants in his bed look wilted and dark in color with the least drying on a warm day or when the Figure 5. A bedrot spot caused by the fungus Pythium aphanidermatum. sash are removed. Soon afterwards the plants collapse in a wet rot and the decaying leaves and stalks sink to a flat black crust over the surface of the ground. Under moist conditions the affected patches spread rapidly in a centrifugal diiection until they may be several feet in diameter and, in the worst cases, entire beds are destroyed. A closer examination of the individual plants shows that the bases of the stalks are first attacked by a soft, slimy, dark, wet rot which advances up to the bases of the leaves. These droop and become dark green and ' watersoaked as they collapse. As they come into contact with other leaves, the rot spreads from leaf to leaf, ru
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