Pathogenicity-Related Compounds Produced by Blast Fungus

  • Tetsu Tsurushima
  • Hitoshi Nakayashiki
  • Yukio Tosa
  • Shigeyuki Mayama


For over a hundred years, it has been discussed whether or not Pyricularia isolates on rice (Oryza sativa) and on crabgrass (Digitaria sanguinalis) belong to the same species, Pyricularia grisea (teleomorph, Magnaporthe grisea). We thought that pyrichalasin H, isolated from a Digitaria isolate, could be used as a marker of the chemotaxonomy of Pyricularia isolates. Pyrichalasin H was only detected in culture filtrates of Pyricularia isolates to infect Digitaria plants among 72 isolates from 20 species of gramineous plants. There was a correlation between pyrichalasin H production and the ability of Pyricularia isolates to infect Digitaria. Pre-treatment of leaf sheaths of crabgrass with pyrichalasin H led to penetration and colonization by nonhost isolates. Thus, we propose that pyrichalasin H may be responsible for the specific pathogenicity of Pyricularia isolates on the Digitaria genus. This result also supports the concept that isolates from rice and other cereals should be referred to as Magnaporthe oryzae and isolates from Digitaria shouldbe referred to as M. grisea. The blast fungus produces necrotic lesions on its original host plant. These lesions might be formed by phytotoxins of blast fungus. Some necrosis-inducing factors have been isolated from Pyricularia isolates. However, their toxins have not been compared to their quantities in cultures of Pyricularia isolates and their activity on host plants. We searched for the necrosis-inducing factor from a Triticum isolate pathogenic on wheat (Triticum aestivum). Pyriculol and epipyriculol were detected as the main necrosis-inducing factors.


Crabgrass Necrosis Pathogenicity-related compound Pyrichalasin H Pyriculol 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Barr, M. E. (1977). Magnaporthe, Telimenella, and Hyponectria (Physosporellaceae). Mycologia, 69, 952–966.CrossRefGoogle Scholar
  2. Cavara, F. (1891). Fungi Longobardiae exsiccati sive mycetum specimina in Longobardia collecta, exsiccata et speciebus novis vel criticis, iconibus illustrata. Pugillus l no. 49 (Cited in Padwick GW. 1950 p. 18).Google Scholar
  3. Couch, B. C. & Kohn, L. M. (2002). A multilocus gene genealogy concordant with host preference indicates segregation of a new species, Magnaporthe oryzae, from M. grisea. Mycologia, 94, 683–693.CrossRefGoogle Scholar
  4. Hebert, T. T. (1971). The perfect stage of Pyricularia grisea. Phytopathology, 61, 83–87.CrossRefGoogle Scholar
  5. Iwasaki, S., Muro, H., Nozoe, S., Okuda, S. & Sato, Z. (1972). Isolation of 3, 4-dihydro-3, 4, 8- trihydroxy-1(2H)-naphtalenone and tenuazonic acid from Pyricularia oryzae Cavara. Tetrahedron Lett., 1, 13–16.CrossRefGoogle Scholar
  6. Iwasaki, S., Nozoe, S., Okuda, S., Sato, Z. & Kozaka, T. (1969). Isolation and structural elucidation of a phytotoxic substance produced by Pyricularia oryzae Cavara. Tetrahedron Lett., 45,3977–3980.CrossRefGoogle Scholar
  7. Kato, H., Yamamoto, M., Yamaguchi-Ozaki, T., Kadouchi, H., Iwamoto, Y., Nakayashiki, H., Tosa, Y., Mayama, S. & Mori, N. (2000). Pathogenicity, mating ability and DNA restriction fragment length polymorphisms of Pyricularia populations isolated from Gramineae, Bambusideae and Zingiberaceae plants. J. Gen. Plant Pathol., 66, 30–47.CrossRefGoogle Scholar
  8. Kim, J. C., Min, J. Y., Kim, H. T., Cho, K. Y. & Yu, S. H. (1998). Pyricuol, a new phytotoxin from Magnaporthe grisea. Biosci. Biotecnol. Biochem., 62, 173–174.CrossRefGoogle Scholar
  9. Kohmoto, K. & Otani, H. (1991). Host recognition by toxigenic plant pathogens. Experientia, 47, 755–764.PubMedCrossRefGoogle Scholar
  10. Kono, Y., Sekido, S., Yamaguchi, I., Kondo, H., Suzuki, Y., Neto, G. C., Sakurai, A. & Yaegashi, H. (1991). Structures of two novel pyriculol-related compounds and identification of naturally produced epipyriculol from Pyricularia oryzae. Agric. Biol. Chem., 55, 2785–2791.Google Scholar
  11. Nukina, M. (1987). Pyrichalasin H, a new phytotoxic metabolite belonging to the cytochalasans from Pyricularia grisea (Cooke) Saccardo. Agric. Biol. Chem., 51, 2625–2628.Google Scholar
  12. Nukina, M. (1998). On the phylogenetic correlations of phytotoxins and related metabolites among blast disease fungi. In K. Kohmoto & O. C. Yoder (Eds.), Molecular Genetics of Host-Specific Toxins in Plant Disease, (pp. 165–166), Kluwer Academic Publishers, Dordrecht.Google Scholar
  13. Nukina, M. & Namai, T. (1991). Productivity of Pyrichalasin H, a phytotoxic metabolite, from different isolates of Pyricularia grisea and from other isolates of Pyricularia spp. Agric Biol. Chem., 55, 1899–1900.Google Scholar
  14. Nukina, M., Sassa, T., Ikeda, M., Umezawa, T. & Tasaki, T. (1981). Pyriculariol, a new phytotoxic metabolite of Pyricularia oryzae Cavara. Agric. Biol. Chem., 45, 2161–2162.Google Scholar
  15. Rossman, A. Y., Howard, R. J. & Valent, B. (1990). Pyricularia grisea, the correct name for the rice blast disease fungus. Mycologia, 82, 509–512.CrossRefGoogle Scholar
  16. Saccardo, P. A. (1880) Fungorum extra-europaeorum Pugillus. Michelia, 2, 136–149.Google Scholar
  17. Tsurushima, T., Don, L. D., Kawashima, K., Murakami, J., Nakayashiki, H., Tosa, Y. & Mayama, S. (2005). Pyrichalasin H production and pathogenicity of Digitaria-specific isolates of Pyricularia grisea. Mol. Plant Pathol., 6, 605–613.CrossRefGoogle Scholar
  18. Walton, J. D. (1996). Host-selective toxins: agents of compatibility. Plant Cell, 8, 1723–1733.PubMedCrossRefGoogle Scholar
  19. Yaegashi, H. & Udagawa, S. (1978). The taxonomical identity of the perfect state of Pyricularia grisea and its allies. Can. J. Bot., 56, 180–183.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • Tetsu Tsurushima
    • 1
  • Hitoshi Nakayashiki
  • Yukio Tosa
  • Shigeyuki Mayama
  1. 1.Faculty of Business, Hannan UniversityMatsubaraJapan

Personalised recommendations