. Diseases of plants induced by cryptogamuc parasites; introduction to the study of pathogenic fungi, slime-fungi, bacteria, and algae. English ed. by William G. Smith. Plant diseases; Parasitic plants. GYMXOSPORANGIUM. 387 may be as long as 10 and are bent like a horn (Fig. 219). A similar case is described by Barclay^ in which the peridia of aecidia on Rhamnus dahurica were very long if produced in dry weather, but short if in moist The aecidiospores are shed during the early part of June, and germinate at once on the bariv of young juniper-twigs; the mycelium growing thence
. Diseases of plants induced by cryptogamuc parasites; introduction to the study of pathogenic fungi, slime-fungi, bacteria, and algae. English ed. by William G. Smith. Plant diseases; Parasitic plants. GYMXOSPORANGIUM. 387 may be as long as 10 and are bent like a horn (Fig. 219). A similar case is described by Barclay^ in which the peridia of aecidia on Rhamnus dahurica were very long if produced in dry weather, but short if in moist The aecidiospores are shed during the early part of June, and germinate at once on the bariv of young juniper-twigs; the mycelium growing thence into the spurs or branches to spread and hibernate. Teleutospores which germinate on Poraaceae other than species of Crataegus have apparently a normal mycelium, but produce pycnidia only, or aecidia with. Fio. 220.—Cross-section through a swelling caused by GiimnoKjtorangUiui on Juniper-stem ; jxireuchyina with large cells and thin walls is present in abiiorual quantity. (After Woernle.) peridia differing from those on Cndargm. My own experiments on the quince and mountain ash regularly produce pycnidia only. Wakker^ summarizes the anatomical changes induced in deformed shoots of hawthorn as follows: cork, collenchyma, sclerenchyma, and chlorophyll are not formed, ligniticution of the cells of medullary rays no longer takes place, and there are few intercellular spaces. Interfascicular cambium is not formed, while activity of the intrafascicular cambium is suspended at an early period, so that the vessels remain incompletely <leveloped. Tlie epidermis is irregularly formed and liable t<» rupture. All parenchymatous cells iiiidcrgo enlargement in a radial dirt-cliDii. Starch is stored up in large (piantity, and the fMrmatidii of calcium oxalate is diniiiiishi'd. '"Oil tlie life-history of Pitrrluia roroiin/d rtir. /(///in/'/j <!'.<," Trans, /.ininaii Sor., Loudon, 1891. proljiiMy the of the long nuridia olituiiied hy royrit-sth
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectparasit, bookyear1897
