Observations on chytridiaceous parasites of phanerogams
Resting spores of the chytrid parasite of Claytonia virginica or “Spring Beauty”, Physoderma claytonianum var. sparrowii, were overwintered in plastic containers buried at the site of collection near Ann Arbor, Mich., USA. Germination took place in the field in early March. The process was followed in the laboratory and involved dehiscence of an operculum, protrusion of an endosporangium, zoospore formation and discharge. Resting spore zoospores were repeatedly placed in contact with young Claytonia plants but there was no evidence that they ever developed into epibiotic, “ephemeral” sporangia. Rather, in all instances within 36 hours the endobiotic, polycentric thallus was established inside the host. Both observational evidence and the speed with which the endobiotic thallus first appeared pointed to the complete lack of an epibiotic stage in our material.
KeywordsPlastic Container Complete Lack Observational Evidence Zoospore Formation Claytonia Virginica
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- Greene, H. C.: Notes on Wisconsin parasitic fungi. IV. Farlowia 1, 569–581 (1944).Google Scholar
- Karling, J. S.: Unrecorded hosts and species of Physoderma. Bull. Torrey Bot. Club 83, 292–299 (1956).Google Scholar
- Lingappa, Y.: Sexuality in Physoderma pulposum Wallroth. Mycologia (N. Y.) 51, 151–158 (1959).Google Scholar
- McKnight, K. H., and D. L. Mumford: Fungal parasites on some Utah species of Portulacaceae. Utah Acad. Proc. 35, 53–55 (1958).Google Scholar
- Savile, D. B. O., and J. A. Parmelee: Some fungal parasites of Portulacaceae. Mycologia (N. Y.) 48, 573–590 (1956).Google Scholar
- Seymour, A. B.: Host Index of the Fungi of North America. xviii-732 pp., Harvard Univ. Press, Cambridge, Mass., 1929.Google Scholar
- Sparrow, F. K.: Chytridiaceous fungi in relation to disease in flowering plants with special reference to Physoderma. In Report of Proceedings, Third Internat. Congress for Microbiol. New York, 1940. xi-833 pp., New York. pp. 514–516.Google Scholar
- Sparrow, F. K.: Observations on chytridiaceous parasites of phanerogams. III. Physoderma claytoniana and an associated parasite. Amer. J. Bot. 34, 325–329 (1947).Google Scholar
- Sparrow, F. K.: Observations on chytridiaceous parasites of phanerogams. VII. A Physoderma on Lycopus americanus. Amer. J. Bot. 44, 661–665 (1957).Google Scholar
- Sparrow, F. K., J. E. Griffin and R. M. Johns: Observations on chytridiaceous parasites of phanerogams. XI. A Physoderma on Agropyron repens. Amer. J. Bot. (in Press).Google Scholar