Annual report of the Board of Control of the New York Agricultural Experiment Station . The ascospores are subelliptical,colorless, one-celled and measure 11 to 15by 4 to 6 ju. Between the asci are slender,Fig. 8. —Perithecial septate, sterile threads known as of C. viticola. The fact that this stage of the fungus hasnever been found in the State althoughdiligent search has been made for it, both before and since theappearance of Dr. Shears paper, makes it reasonably certain thatthe perithecial stage of the fungus plays no important role in thedissemination or perpetuation
Annual report of the Board of Control of the New York Agricultural Experiment Station . The ascospores are subelliptical,colorless, one-celled and measure 11 to 15by 4 to 6 ju. Between the asci are slender,Fig. 8. —Perithecial septate, sterile threads known as of C. viticola. The fact that this stage of the fungus hasnever been found in the State althoughdiligent search has been made for it, both before and since theappearance of Dr. Shears paper, makes it reasonably certain thatthe perithecial stage of the fungus plays no important role in thedissemination or perpetuation of the fungus with us. Pycnidia.— This stage of the fungus is very abundant. It com-monly occurs in the bark of the previous season or of two seasonsprevious. Fig. 9 (Plate VIII). The young pycnidium forms imme-diately underneath the layer of cork of the last annual ring of YZ (Plate IX). As it increases in size it lifts up this cork layerand the larger portion of the pycnidium is to be found on the the berry the stroma develops in the hypodermal parenchyma. New York Agricultural Experiment Station. 259 immediately beneath the epidermis and distorted parenchyma cells arefrequently included in it. With the enlargement of the pycnidiumthe underlying cortical tissue is compressed somewhat, giving in-creased area within the collapsing berry and the epidermis andcuticle are lifted so that the pycnidium breaks through and de-velops on the outside to approximately the same extent that itdoes inside. Fig. 11 (Plate IX). The pycnidia on the woody partsare to be found in greatest abundance in early spring. After theJune rains only the base of the pycnidium remains and later thecavity in the tissue occupied by #the pycnidium is the only visibleevidence of this stage. Canes which are severely infected the previous season often developgreat quantities of the pycnidia, while occasionally pycnidia aredeveloped on the current seasons growth. In a vineyard wherelightnin
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectagriculture, bookyear
