. Diseases of plants induced by cryptogamic parasites; introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae. Plant diseases; Parasitic plants; Fungi. 120 FHYCOMYCKTES. tufts, iuul tt)nii a white bonier round the brown parts of the leaf; they are monopodially branched and produce terminal sporangia (gonidia), which are easily detached. The sporangia on germination either pro- duce a varying number of zoospores, or germinate directly like conidia to form a mycelium capable of pro- ducing new conidia. The potato-disease is distin- guished from Phyto])htliora omnivora
. Diseases of plants induced by cryptogamic parasites; introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae. Plant diseases; Parasitic plants; Fungi. 120 FHYCOMYCKTES. tufts, iuul tt)nii a white bonier round the brown parts of the leaf; they are monopodially branched and produce terminal sporangia (gonidia), which are easily detached. The sporangia on germination either pro- duce a varying number of zoospores, or germinate directly like conidia to form a mycelium capable of pro- ducing new conidia. The potato-disease is distin- guished from Phyto])htliora omnivora in the absence of sexual reproduction by oospores.^ It is generally assumed that the mycelium hibernates in potato-tubers, from which the fungus recommences to spread in spring. Boehm,- however, contests this, and holds the hibernation of the fungus to be quite unknown, and that from the tubers of Fio. of a Beech-seedling with swarm- a disCaSCd plant, either a spores a, h ; the germ-tubes from tliese penetrate ^ between adjacent epidermal cells ; c, sporangium with health V plant Or llOUC at zoospores already germinating inside it, d, f\ e, -a J r , germ-tube which has penetrated directly into an all reSultS epidermal cell; jr, germ-tube which, after growing <!Aiter*R"Hanr V ''^"' '''^'' '''^'''" ""^'^^ "^ '^'^^*""*â '^'''^ Phjituplitliom potato- disease is quite distinct from {(i) the potato-blight or wet-rot which, according to Boehm, is the result of closing up of the lenticels, with a consequent stoppage of respiration; {h) bacteriosis, which will be considered amongst the bacterial diseases of plants. Lagerheim^ has pointed out that Solanum murimtiim much cultivated in Ecuador on account of its edible fruit, has been for many years subject to attack from Fhi/tophthora in/cstam; the fruits sicken and rot off before ripening. The. rhis is a well-known point of controversy, for an intei-esting discussion of ;h we would r
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Keywords: ., bookcentury1800, bookdecade1890, bookpublisherl, booksubjectfungi
