It was not till De Bary (1866) made known the true nature of parasitic Fungi, based on his researches between 1853-1863, that the vast domain of epidemic diseases of plants was opened up to fruitful investigation, and such modern treatises as those of Frank (1880 and L895), Sorauer (1886), Kirchner (1890), were gradually made possible.
AUTH0RITne5.General and Historical.Berkeley, Vegetable Pathology, Gardeners Chronicle (1854) p. 4; Plowright, British Uredineae and Ustilagineae (1889); Erik,sson and Henning, Die Getreideroste (Stockholm, 1896); De Bary, Comparative Morph.
Bary chelidae (Barychelus, Plagiobothrus).
(After de Bary.) In A several cells of the epidermis plants.
De Bary and others, while more recently, as cytology (q.v.), the intimate study of the cell and its contents has attracted considerable attention.
In 1865 De Bary suggested the possibility that such lichens as Collema, Ephebe, &c., arose as a result of the attack of parasitic Ascomycetes upon the algae, Nostoc, Chroococcus, &c. In 1867 the observations of Famintzin and Baranetzky showed that the gonidia, in certain cases, were able to live outside the lichen-thallus, and in the case of Physcia, Evernia and Cladonia were able to form zoospores.
In illustration of the very different estimates that have been made, however, may be mentioned that of De Bary in 1872 of 150,000 species, and that of Cooke in 1895 of 40,000, and Massee in 1899 of over 50,000 species, the fact being that no sufficient data are as yet to hand for any accurate census.
(After De Bary.) more or less branched (Peronospora) or coiled (Protomyces)haustorium.
Bary.) (X 400.) undergoes segmentation into more or less numerous globular masses, each of which secretes an enveloping cell-wall and becomes a spore (endospore), and branched systems of sporangia may arise as before (Thamnidium).
De Bary brought forward very strong evidence for the origin of the ascocarp in Sphaerotheca and Erysiphe by a sexual process, but Harper in 1895 was the first to prove conclusively, by the observation of the nuclear fusion, that there was a definite fertilization in Sphaerotheca Humuli by the fusion of a male (antheridial) nucleus with a female, ascogonial (oogonial) nucleus.
(After De Bary.) A, Small portion of mycelium D, The perithecium.
(After De Bary.) its characters.
(After De Bary.) B, Part of vertical section through leaf of Berberis From Strasburger's Lehrbuch der Botanik, by permission of Gustav Fischer.
Teil (1892 onwards); Zopf, Die Pilze (Breslau, 1890); De Bary, Comparative Morphology of Fungi, &c. (Oxford, 1887); von Tafel, Vergleichende Morphologie der Pilze (Jena, 1892); Brefeld, Ureters.
In 1876, however, Cohn had seen the spores germinate, and Koch, Brefeld, Pratzmowski, van Tieghem, de Bary and others confirmed the discovery in various species.
In the hands of Brefeld, BurdonSanderson, de Bary, Tyndall, Roberts, Lister and others, the various links in the chain of evidence grew stronger and stronger, and every case adduced as one of " spontaneous generation " fell to the ground when examined.
(After de Bary.) a, a chain of motile rodlets still growing and dividing (bacilli).
(After de Bary.) Two of the long filaments (B, fig.
(After de Bary.) "1, fragments of filaments with ripe spores; 2-5, successive stages in the germination of the spores, the remains of the spore attached to the germinal rodlets.
These forms are termed by Fischer Metatrophic, because they require various kinds of organic materials obtained from the dead remains of other organisms or from the surfaces of their bodies, and can utilize and decompose them in various ways (Polytrophic) or, if monotrophic, are at least unable to work them up. The true parasites - obligate parasites of de Bary - are placed by Fischer in a third biological group, Paratrophic bacteria, to mark the importance of their mode of life in the interior of living organisms where they live and multiply in the blood, juices or tissues.
(After De Bary.) uredospores probably survive the winter in Europe as well as in Australia and give rise to the rust of the following year.