. Diseases of cultivated plants and trees. Plant diseases; Plants -- Wounds and injuries; Plants, Protection of; Trees -- Diseases and pests. 158 DISEASES OF CULTIVATED PLANTS is somewhat erratic in its appearance, and during certain seasons it covers both surfaces of the leaves of gooseberries with a delicate greyish-white mildew. Less frequently the fruit is also attacked. When the mycelium is well established on the leaf, it becomes covered with a mass of conidia, giving to it a mealy appearance. The ascigerous condition is usually produced in abundance later in the. KiG. ^o.—Microsphaera ^
. Diseases of cultivated plants and trees. Plant diseases; Plants -- Wounds and injuries; Plants, Protection of; Trees -- Diseases and pests. 158 DISEASES OF CULTIVATED PLANTS is somewhat erratic in its appearance, and during certain seasons it covers both surfaces of the leaves of gooseberries with a delicate greyish-white mildew. Less frequently the fruit is also attacked. When the mycelium is well established on the leaf, it becomes covered with a mass of conidia, giving to it a mealy appearance. The ascigerous condition is usually produced in abundance later in the. KiG. ^o.—Microsphaera ^rossuluriac. i, gooseberry leaf with patches of mildew ; 2, a perithccium with its appi-nd- ages; 3, tip of an appendage ; 4 and 5, asci containing sjiorcs. Fig. I nat. size ; the remainder highly mag. season, and is readily recognised under the microscope by the elaborate tips of the appendages. Mycelium delicate, greyish-white on both surfaces of the leaf; perithecia usually in small, scattered groups, dark brown, appendages once or twice as long as diameter of j)eridium, 4-6 times forked at the tip; asci 3-10, ovate, containing 3-6 spores of variable size, 20-30 x 12-15 /*• As a rule this jmrasite cannot be considered as injurious. Spraying with potassium sulphide is effective if commenced when the leaves are 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
