Abstract
In the present paper fine structure of antheridium and oogonium ofPhytophthora macrospora (Sacc.)S. Ito etI. Tanaka, the downy mildew fungus of rice plants was discussed.
Before the fertilization some nuclei and a large number of mitochondria were scattered in the cytoplasm of the antheridium. Many lipid granules were observed in the peripheral region, but vacuoles did not appear at this stage of antheridium. Many mitochondria were associated in the neighborhood of the fertilization pore. The wall at the pore was very thin, but the wall surrounding the pore was slightly swollen towards the inside.
In the oogonium, many nuclei, mitochondria and cytoplasmic matrix were observed at the peripheral part. A large number of lipid granules was found in the oogonium, but they were more numerous in the peripheral region. The vacuoles developed as the oogonium matured. They were enveloped by tonoplast and contained vacuolar matrix. Many electron dense granules were in contact with the tonoplast or free in the vacuoles, and they were larger in the central part. As stated above, wall at the fertilization pore was thin. However, the oogonial wall surrounding the pore swelled protruding into the oogonium. An electron-dense layer was recognized between the antheridial and oogonial wall, and the walls of both the organs were closely in contact with each other.
Similar content being viewed by others
References
Akai, S. &Fukutomi, M. (1964) Taxonomic position of the pathogen of the downy mildew in rice plants.Special Res. Rep. on Dis. and Insect Forcasting. No. 17:112–125.
Akai, S., Fukutomi, M., Ishida, N. &Kunoh, H. (1967) An anatomical approach to the mechanism of fungal infection in plants. The Dynamic Role of Molecular Constituents in Plant-Parasite Interaction (Mirocha, C. J. &Uritani, I. (ed.)). p. 1–20.
Bracker, C. E. (1967) Ultrastructure of fungi.Ann. Rev. Phytopathol. 5:343–374.
Chapman, J. A. &Vujičič, R. (1965) The fine structure of sporangia ofPhytophthora erythroseptica Pethyb.J. gen. Microbiol. 41:275–282.
Colhoun, J. (1966) The biflagellate zoospore of aquatic Phycomycetes with particular reference toPhytophthora spp. In the Fungus Spore,Proc. Symp. Colston Res. Soc., 18th, Bristol, England, 1966:85–92 (Madelin, M. F., ed., Butterworths. London).
Ehrlich, M. A. &Ehrlich, H. G. (1965) Ultrastructure ofPhytophthora infestans.Phytopathology 55:1056 (Abstr.).
Ehrlich, M. A. &Ehrlich, H. G. (1966) Ultrastructure of the hyphae and haustoria ofPhytophthora infestans and hyphae ofP. parasitica.Canad. J. Bot. 44:1495–1503.
Ferris, V. R. (1954) Note on the flagellation ofPhytophthora infestans (Mont.)deBary.Science 120:71–72.
Fukutomi, M. &Akai, S. (1966a) Fine structure of the zoospores, cystospores and germ tubes ofSclerophthora macrospora.Trans. Mycol. Soc. Japan 7:199–202.
Fukutomi, M. &Akai, S. (1966b) Fine structure of abnormal chloroplasts in the leaves of rice plants affected by the downy mildew fungus.Ann. Phytopathol. Soc. Japan 32:66–67. (Abstr.)
Fukutomi, M. &Akai, S. (1966c) Fine structure of fungal hyphae and leaf tissues affected by the downy mildew fungus in rice plants.Ann. Phytopathol. Soc. Japan 32:66–67. (Abstr.)
Fukutomi, M., Akai, S. &Shiraishi, M. (1967) Fine structure of cell membranes in the downy mildew fungus and rice plants.Ann. Phytopathol. Soc. Japan 33:72 (Abstr.).
Fukutomi, M., Akai, S. &Shiraishi, M. (1969) Ultrastructure of antheridium and oogonium of the downy mildew fungus of rice plants.Forsch. Gebiet Pflanzenkrankh (Shokubutsu Byogai Kenkyu,) Kyoto 7(8):79–80.
Fukutomi, M., Shiraishi, M. &Akai, S. (1968) Ultrastructural observation of antheridia and oogonia of the downy mildew fungus in rice plants.Ann. Phytopathol. Soc. Japan 34:177–178 (Abstr.).
Ho, H. H., Zachariah, K. &Hickman, C. J. (1968) The ultrastructure of zoospores ofPhytophthora megasperma var. sojae.Canad. J. Bot. 46:37–41.
Hohl, H. R. &Hamamoto, S. T. (1967) Ultrastructural changes during zoospore formation inPhytophthora parasitica.Amer. J. Bot. 54:1131–1139.
Hohl, H. R., Hamamoto, S. T. &Uehara, M. (1966) Cell membrane formation during cleavage inPhytophthora. Bact. Proc. 1966: G74.
Kole, A. P. (1965) Flagella. Ainsworth et al. (ed.):The fungi 1:77–93.
McDonough, E. S. (1953) Studies on the downy mildew of rice plant. A cytological study of the development of the oospore ofSclerospora macrospora (Sacc.).Trans. Wis. Acad. Sci., Arts and Letters 38:211–218.
Miles, L. E. &Epps, J. M. (1942) The downy mildew disease of oats caused bySclerospora macrospora.Phytopathol. 32:867–878.
Stevens, F. L. (1899) The compound oosphere ofAlbugo Bliti.Bot. Gaz. 28:149–176.
Tanaka, I. (1940)Phytophthora macrospora (Sacc.)S. Ito etI. Tanaka on wheat plant.Ann. Phytopathol. Soc. Japan 10:127–138.
Tasugi, H. (1953) Studies on the downy mildew of rice plant.Bull. Nat. Inst. Agricult. Sci. Series C(2):1–48.
Thirumalachar, M. J., Shaw, C. G. &Narasimhan, M. J. (1953) The sporangial phase of the downy mildew onEleusine coracana with a discussion of the identity ofSclerospora macrospora Sacc.Bull. Torry Bot. Club. 80:299–307.
Ullstrup, A. J. (1952) Observations on crazy top of corn.Phytopathology 42:675–680.
Wager, H. (1896) On the structure and reproduction ofCystopus candidus.Ann. Bot. 10:295–342.
Whitehead, M. D. (1958) Pathology and pathological histology of downy mildew,Sclerophthora macrospora, on six graminicolous hosts.Phytopathology 48:485–493.
Author information
Authors and Affiliations
Additional information
Contribution No. 252.
Rights and permissions
About this article
Cite this article
Fukutomi, M., Akai, S. & Shiraishi, M. Fine structure of antheridia and oogonia of Phytophthora macrospora, the downy mildew fungus of rice plants. Mycopathologia et Mycologia Applicata 43, 249–258 (1971). https://doi.org/10.1007/BF02051744
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02051744