. Diseases of plants induced by cryptogamic parasites; introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae. Plant diseases; Parasitic plants; Fungi. SPHACELOTHECA. 805 period, and produce three-celled promycelia with elongated ovoid conidia, which sprout indefinitely. In nutritive solutions two or three promycelia may be produced. Schizonella.^ The spores are produced in series on the reproductive hyphae. At first two-chambered by means of a cross-septum, they later separate into two loosely-joined cells and form twin-spores; each half germinates like an Ustilago-
. Diseases of plants induced by cryptogamic parasites; introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae. Plant diseases; Parasitic plants; Fungi. SPHACELOTHECA. 805 period, and produce three-celled promycelia with elongated ovoid conidia, which sprout indefinitely. In nutritive solutions two or three promycelia may be produced. Schizonella.^ The spores are produced in series on the reproductive hyphae. At first two-chambered by means of a cross-septum, they later separate into two loosely-joined cells and form twin-spores; each half germinates like an Ustilago-spove. Schizonella melanogramma (D. C.) ( America). A species found on leaves of various species of Carex. The spores, when mature, escape by short fissures in the upper epidermis of the host; they are black and coupled in pairs by a short connection. They germinate in water and produce a promycelium of three or four cells from which conidia are given off. In nutritive solution the promycelia produce conidia, which fall off' and sprout yeast-like for a time. Tolyposporium. The sporogenous hyphae form tangled masses, and produce their spores firmly bound together in balls. The single spores are large, somewhat angular or spherical, and each germinates like a spore of Ustilago. Tolysporium junci (Schroet.) causes the formation of gall-like outgrowths on the ovaries, fiower-stalks, and haulms of Juncus hufonius and J. capitatus. In these the spores are developed and escape as spore-balls. The spores, after a prolonged rest, germinate in water and produce four-celled promycelia, from which ovoid or spindle-shaped conidia are given off. In nutritive solutions many of the cells in each spore-ball germinate and produce promycelia, at first four-celled, later further divided by new septa; the conidia sprout and grow on till they reach the air, where aerial •conidia are Fig. 165.—Tolyposporium junci. Spore-mass. One spore has germinated and given off an eight-celled pro
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Keywords: ., bookcentury1800, bookdecade1890, bookpublisherl, booksubjectfungi
