Fungi and fungicides; a practical manual, concerning the fungous diseases of cultivated plants and the means of preventing their ravages . allerthan healthy ones, and have a generally unhealthy ap-pearance, later turning yellow, then brown. The canesfinally become blackened and die. The mycelium, or vegetative portion, of the rasp-berry anthracnose consists of slender, microscopic threadswhich penetrate between the cells of the plant, andabsorb their nourishment; the cells thus robbed becomefirst discolored, and then they shrivel and dry up, thetissues finally becoming dead. Toward the center
Fungi and fungicides; a practical manual, concerning the fungous diseases of cultivated plants and the means of preventing their ravages . allerthan healthy ones, and have a generally unhealthy ap-pearance, later turning yellow, then brown. The canesfinally become blackened and die. The mycelium, or vegetative portion, of the rasp-berry anthracnose consists of slender, microscopic threadswhich penetrate between the cells of the plant, andabsorb their nourishment; the cells thus robbed becomefirst discolored, and then they shrivel and dry up, thetissues finally becoming dead. Toward the center ofthis dying tissue the mycelium threads unite to form amass of slender club-shaped bodies {lasidia), whichpush outward on the thin bark cuticle, or skin, untilthe latter is ruptured. On the end of each of theseclub-shaped bodies there is produced a single spore(conidiiim). Both the club-shaped bodies and the sporesare at first enveloped in a yellowish, gelatinous covering,which, however, is soluble in water, so that during thefirst rainfall it dissolves and the spores escape. Theshajoe of the spores is represented in Plate XI; they. PLATE XI. AMUKAOJSOSIS OF KASPBEKRY. 100 FUKGI AND FUi^GICIDES are carried to new places on the plant during rains, andthere they germinate and start the disease anew. Manyof them are probably blown from i^lant to plant andfield to field by the wind, and thus the disease is of these spores are the so-called summer spores(conidia); no true winter spores have yet been is supposed that the mycelium is i^erennial, carryingthe fungus through the winter. Treatment.—Raspberry foliage is yery sensitive tothe corrosive action of fungicides, so that care in treat-ment is necessary. The most successful results in pre-venting this disease, as yet obtained, are those reportedby Mr. W. J. Green, of the Ohio Experiment Station,who used a dilute Bordeaux mixture. His directionsare as follows : ^^The first application should be madeearly in th
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectpathoge, bookyear1896
