. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 363 The seciospores are borne in secia which rest in orange or yellow spots often strongly thickened. Pycnia abound. The aecium with its thick peridium is erumpent and projects to some distance above the host surface, this character giving rise to the separate form- genus, Roestelia. The peridial margin which may be lacerate or fimbriate is used in specific characteriza- tion. The spores are borne and function as in ordinary secia. They bear several germ pores. jEciospores germi- nate at once and
. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 363 The seciospores are borne in secia which rest in orange or yellow spots often strongly thickened. Pycnia abound. The aecium with its thick peridium is erumpent and projects to some distance above the host surface, this character giving rise to the separate form- genus, Roestelia. The peridial margin which may be lacerate or fimbriate is used in specific characteriza- tion. The spores are borne and function as in ordinary secia. They bear several germ pores. jEciospores germi- nate at once and if they fall upon suitable coniferous hosts bring about infection. The mycelium penetrating the leaf or branch often induces large hypertrophy. In spring in moist weather the telio- spores are found in spore masses com- j r .1 Fig. 264.—Gymnosporangium teliospores. a, G. cla- posed OI tne spores, variseforme; 6, G. globosum; c, G. macropus; d, G. which are usually iiidus-avis; e. G. nelsoni;/, G. clavipes. After King. orange or yellow, and of their long gelatinous pedicels. Each cell usually bears several germ pores near the septum through one of which the tube emerges. The teliospores germinate immediately in sJiu by typical 4-celled promycelia and four basidiospores are produced on each 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 Stevens, Frank Lincoln, 1871-1934. New York : Macmillan
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectfungi, bookyear1913
