Abstract
THE life-history of Rarnularia onobrychidis is described by S. J. Hughes in a recent paper (Trans. Brit. Mycol. Soc., 32, Pt. 1, 34 ; 1949). This fungus causes a leaf spot of sainfoin: it produces chains of conidia from spring to early autumn, and also makes sclerotia in winter. The latter remain viable for a considerable period, and produce conidia from the neck cells. Pathogenicity of the fungus has been proved by inoculation with conidia ; but no perithecial stage has yet been found. Another leaf spot of sainfoin, caused by Septoria orobina, has also been described by the same author (ibid., pp. 60–62). W. C. Moore mentions three new fungal plant diseases (ibid., pp. 95–99). Zyihia fragarice, which is responsible for a leaf blotch on strawberry, can also produce similar damage on Geum. A downy mildew on Alyssum saxatile was found due to Peronospora galligena. Downy mildew of the vine, Plasmopara viticola, has probably been confused with powdery mildew on the same host ; but several authenticated records in England are now given. A fourth malady, black heart of potato, is non-parasitic ; it may be due to unsatisfactory clamping conditions, though it is possible that the symptoms were induced by high soil temperature while the tubers were still attached to the.parent plant.
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New Plant Diseases. Nature 164, 268 (1949). https://doi.org/10.1038/164268a0
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DOI: https://doi.org/10.1038/164268a0