Two newhalophytophthora species,H. tartarea andH. masteri, from intertidal decomposing leaves in saltmarsh and mangrove regions
- 35 Downloads
Two new pythiaceous fungi were obtained from decaying leaves submerged in saltmarsh environments of the east coast of the U.S.A., or fringing mangroves in the Bahama Islands, and are described here asHalophytophthora tartarea andH. masteri. The two species have superficially similar zoosporangia whose dehiscence tubes have ragged-looking apices. However, differences in fine structures and development of the dehiscence tube and plug, characteristics of the dehiscence plugs, and presence or absence of vesicles clearly distinguish the two species.Halophytophthora masteri is the only species ofHalophytophthora that has a zoospore release mechanism involving both an extruded plug and a vesicle. Cultural properties concerning growth and asexual reproduction at various salinities and temperatures are also different between the two, probably reflecting adaptation to their respective habitats. Though zoospore release inH. masteri occurs spontaneously from mature zoosporangia, it is remarkably enhanced inH. tartarea and alsoH. masteri by mildly dehydrating mature zoosporangia followed by rewetting with seawater, which suggests a possible relation between the asexual reproduction of these oomycetes and the tidal rhythm in their natural habitats.
Key WordsHalophytophthora masteri Halophytophthora tartarea mangrove oomycetes saltmarsh
Unable to display preview. Download preview PDF.
- Anastasiou, C. J. and Churchland, L. M. 1969. Fungi on decaying leaves in marine habitats. Can. J. Bot.47: 251–257.Google Scholar
- Fell, J. W. and Master, I. M. 1975. Phycomycetes (Phytophthora spp. nov. andPythium sp. nov.) associated with decaying mangrove (Rhizophora mangle) leaves. Can. J. Bot.53: 2908–2922.Google Scholar
- Gerrettson-Cornell, L. and Simpson, J. 1984. Three new marinePhytophthora species from New South Wales. Mycotaxon19: 453–470.Google Scholar
- Ho, H. H., Chang, H. S. and Hsieh, S. Y. 1991.Halophytophthora kandeliae, a new marine fungus from Taiwan. Mycologia83: 419–424.Google Scholar
- Ho, H. H., Nakagiri, A. and Newell, S. Y. 1992. A new species ofHalophytophthora from Atlantic and Pacific subtropical islands. Mycologia84: 548–554.Google Scholar
- Nakagiri, A. 1993. Growth and reproduction ofHalophytophthora species. Trans. Mycol. Soc. Japan34: 87–99.Google Scholar
- Newell, S. Y. 1992. Autumn distribution of marine Pythiaceae across a mangrove-saltmarsh boundary. Can. J. Bot.70: 1912–1916.Google Scholar
- Newell, S. Y. and Fell, J. W. 1994. Parallel testing of media for measuring frequencies of occurrence forHalophytophthora spp. (Oomycota) from decomposing mangrove leaves. Can. J. Microbiol.40: 250–256.Google Scholar
- Pegg, K. G. and Alcorn, J. L. 1982.Phytophthora operculata sp. nov., a new marine fungus. Mycotaxon16: 99–102.Google Scholar
- Stamps, D. J., Waterhouse, G. M., Newhook, F. J. and Hall, G. S. 1990. Revised tabular key to the species ofPhytophthora. Mycol. Pap.162: 1–28.Google Scholar