Abstract
A description is provided for Puccinia chrysanthemi. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Chrysanthemum boreale, C. decaisneanum, C. hortum, C. indicum, C. makinoi, C. pacificum, C. shimotomaii, C. shiwagiku, C. sinense and C. zawadskii. DISEASE: Black rust of cultivated chrysanthemum. Attacks mainly leaves, killing them and causing premature defoliation. Severe foliar infection in certain varieties is accompanied by slight infection of stems and occasionally of the involucre. Affected plants often become stunted and produce few flowers. Heavy damage was caused in Germany during 1926-27 (8: 242). GEOGRAPHICAL DISTRIBUTION: Africa (Congo, Ethiopia, Kenya, Malawi, Mauritius, Morocco, Rhodesia, South Africa, Tanzania, Uganda); Asia (China, India, Israel, Japan, Korea, U.S.S.R.); Australasia and Oceania (Australia, Hawaii, New Zealand, Tasmania); Europe (Azores, Belgium, Bulgaria, Denmark, Finland, France, Germany, Great Britain, Holland, Iceland, Italy, Malta, N. Ireland, Norway, Poland, Portugal, Spain, Sweden, Switzerland, U.S.S.R., Yugoslavia); N. America (Bermuda, Canada, U.S.A.); Central America & W. Indies (Dominican Republic); S. America (Argentina, Chile, Uruguay). (CMI Map 117, Ed. 2, 1964). TRANSMISSION: Teliospores have been reported from Japan, N. America and Sweden; elsewhere the fungus is known in the uredial stage only. It has been shown that urediospores wintered in the open can germinate in the spring (Jacky, Z. Pfl.-Krankh. 10: 132, 1900; Zbl Bakt. II, 10: 369, 1903; 18: 88, 1907). It is believed that urediospores can remain viable through winter on woodwork, glass, fallen leaves or in the soil (Pape, Gartenwelt 32: 623, 1928). No perennial mycelium has been found (Gibson, New Phytol. 3: 188, 1904).