. Diseases of cultivated plants and trees. Plant diseases; Plants -- Wounds and injuries; Plants, Protection of; Trees -- Diseases and pests. 90 DISEASES OF CULTIVATED PLANTS Seedling cabbage disease {Olpidiurti brassicae, Dang.) often causes devastation in beds of seedling cabbages; the injury comes from the gardener's point of view under the category of ' damping off.' The tender cells of the young stem are attacked by the fungus, soon the plant droops, falls down, and dies. Sporangia, solitary or several in each cell of the host, the long slender tube from which the zoospores escape often p
. Diseases of cultivated plants and trees. Plant diseases; Plants -- Wounds and injuries; Plants, Protection of; Trees -- Diseases and pests. 90 DISEASES OF CULTIVATED PLANTS Seedling cabbage disease {Olpidiurti brassicae, Dang.) often causes devastation in beds of seedling cabbages; the injury comes from the gardener's point of view under the category of ' damping off.' The tender cells of the young stem are attacked by the fungus, soon the plant droops, falls down, and dies. Sporangia, solitary or several in each cell of the host, the long slender tube from which the zoospores escape often passes through a layer of four or five cells to reach the surface of the host-plant. Zoospores i-ciliate, globose. Resting-spores tinged yellow, Fig. 17.—Olpldiuni brassicae. i, zoosporangia in cells of cabbage leaf; 2, zoospores; 3, resting- spores. All highly mag. From a scientific standpoint this fungus should be recog- nised from the similar effects produced by Pythium de barya- ?tum (Hesse), although the practical preventive measures apply equally to both pests. Plenty of sunlight, and absence of excess of moisture in soil and air are the only practical remedies. Where the disease has shown itself is an indication that the locality is too damp. Woronin, Pringsh. Jahrb. (1878), p. 557. Olpidium hmnae (Schrot.). This parasite is met with in the epidermal cells of the duckweed {Levina minor). Zoosporangia globose, with a long beak, 18-20 /x diam., resting-spores globose, almost colourless, 12-20 /'. 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 Massee, George, 1850-1917. New York : Macmillan
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Keywords: ., bookpublishernewyorkmacmillan, booksubjectplantdis, bookyear1910
