Fungi and fungicides; a practical manual, concerning the fungous diseases of cultivated plants and the means of preventing their ravages . most destructive of these mal-lidics. It is closely related to thedowny mildew of the potato, andproduces *gray, slightly violet,patches (i a velvety texture, uponthe under side of the leaves, whilefrom the upper side they liave apale yellow shade, due to the lossof the green color.* If a crosssection of the leaf be made throughone of these patches, and ii minutejiiece placed under the microscopeon a glass slide, the fungus Vv-illbe seen to have a structure
Fungi and fungicides; a practical manual, concerning the fungous diseases of cultivated plants and the means of preventing their ravages . most destructive of these mal-lidics. It is closely related to thedowny mildew of the potato, andproduces *gray, slightly violet,patches (i a velvety texture, uponthe under side of the leaves, whilefrom the upper side they liave apale yellow shade, due to the lossof the green color.* If a crosssection of the leaf be made throughone of these patches, and ii minutejiiece placed under the microscopeon a glass slide, the fungus Vv-illbe seen to have a structure similarto Fig. 75, which represents onthe lower part the cells of the leafhaving the mycelium of the fun-2:us runnins: between some ofthem, sending here and theresuckers into the cells them-selves to absorb their contents,and pushing out through the FIG 75. SPIJfACH IMIXBEW. , ,, . ^ ^ « +Uo -Pvnifinrr Section of leaf showiui^nivceii- brcathmg porc, tt, the truiting MagJifieJr^• stalk, i, which bears the spores, c. At d one of the spores is shown, more magnified. These spores are scattered to other plaiits, where they germinate. THE SPIXACH AT^^THRACNOSE 177 by sending out slender tubes, wliich may enter the leavesthrough the breathing pores. The Spinach Anthracnose Colletotrichum spinacece This is, perhaps, the most destructive of the spin-ach diseases, as it grows rapidly, and, in consequence,soon spreads over many plants. ^^The first indicationof its presence, writes Dr. Halsted, is an indescriba-ble moist appearance of the usually circular affected part; followed by the appearanceof minute brown pustules, while atthe same time a gray color developsand the diseased area becomes anthracnose is shown in , where an affected leaf, muchreduced in size, is seen, with someportions killed by the fungus. Noparticular part of the leaf is firstattacked, and, therefore, no twoleaves appeiir alike. In some casesthe largest leaves will be diseased,in other plants only th
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectpathoge, bookyear1896
