. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 262 FUNGOUS DISEASES OF PLANTS The fungus. The life history of the fungus has been con- siderably studied, and it is probable that some spore stages which have been described are not at any rate common stages in the life cycle. In general, two spore-producing stages may be found, the conidial and the ascigerous stages. The conidial stage has been described as Ramularia Tulasnei. This appears in early summer, as a rule, or so soon as the pale centers of the spots have been developed
. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 262 FUNGOUS DISEASES OF PLANTS The fungus. The life history of the fungus has been con- siderably studied, and it is probable that some spore stages which have been described are not at any rate common stages in the life cycle. In general, two spore-producing stages may be found, the conidial and the ascigerous stages. The conidial stage has been described as Ramularia Tulasnei. This appears in early summer, as a rule, or so soon as the pale centers of the spots have been developed. Small, tuberculate stromatic masses are produced upon the mycelium beneath the epidermis, and from these arise a small group of simple hyphse, which rupture the. Fig. 114. Leaf Spot of Strawberry epidermis and produce conidia which may become one or several times septate. The conidia, according to Dudley, measure 20- 40 x 3-5^ (Fig. 115, a). The ascigerous stage is not so commonly found and is in no case developed until late summer. A membranous perithecium, characteristic of this family, is then produced within the leaf, al- though at maturity a considerable part of the perithecium may be exposed. Relatively few asci are developed, the asci containing invariably eight hyaline, uniseptate spores with acute tips (Fig. 115). It would appear that the spores are not ordinarily mature until late winter, or at least not ejected until that time. Moreover,. 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 Duggar, Benjamin M. (Benjamin Minge), 1872-1956. Boston ; New York : Ginn
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