Phakopsora apoda (Uredinales) from Ascension Island

Phakopsora apoda (Uredinales) from Ascension Island

Notes and brief articles 19° the latter the smooth, 0-1 septate conidia are distinctly tapered towards the apices rather than obtuse. One of the aut...

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Notes and brief articles

19°

the latter the smooth, 0-1 septate conidia are distinctly tapered towards the apices rather than obtuse. One of the authors (M.D.M.) expresses his appreciation to Shri H. K. Choudhury, Principal & Head of Research, S.F.S. College-cum-Research Centre, Burnihat, Assam for providing facilities .

REFERENCES

PETRAK, F. (1953). Colletogloeum n. gen ., eine neue Melanconieen-Gattung. Sydowia 7, 367-369. SUTTON, B. C. (1964). Coe1omycetes III. Annellolacinia gen. nov., Aristastoma, Phacocytostroma, Seimatosporium, etc. Mycological Papers 97,1-42. SUTTON, B. C. (1980). The Coelomycetes. Kew:

CommonwealthMycological Institute.

PHAKOPSORA APODA (UREDINALES) FROM ASCENSION ISLAND H. B . GJAERUM

Norwegian Plant Protection Institute, P.O. Box 70, N 1432 As-NLH, Norway AND R. W. G. DENNIS

Herbarium, Royal Botanic Gardens, Kew, Surrey, TW9 3AE, England Two sterile grass collections made by Mr Q. Cronk on Ascension Island and sent to the Herbarium, Royal Botanic Gardens, Kew have been studied. Microscopical examination indicated that the two specimens were infected by the same fungus . Only uredinia occurred, but spores and paraphyses showed that the fungus belonged to either Phakopsora Diet. or Physopella Arth. In 1979, R. W. G. Dennis collected a rustinfected grass from Opua, New Zealand, kindly identified by the late Dr C. E. Hubbard as Pennisetum clandestinum Hochst. The rust was identified as Phakopsora apoda (Har. & Pat.) Mains, recently reported from New Zealand by Dingley (1977) on the same host. This rust showed great similarity to that from Ascension Island, and so did the host plants, both in the hairy ligules and leaves. Pennisetum clandestinum is a widespread weed, not uncommon on Green Mountain in Ascension. Careful examination of a specimen (K) from this locality revealed a few uredinial sori of the same rust fungus. Description of the fungus: Uredinia with incurved paraphyses, wall thickened dorsally and apically, hyaline to yellowish, Urediniospores 18-28 (-32) x 14-20 (-23) 11m (NZ specimen 1827 x 14-19 lim ), ellipsoid, wall about 1 pm thick,

Trans. Br. mycol. Soc. 78 (1), (1982).

hyaline becoming yellowish, densely echinulate, with several scattered germ-pores. Specimens examined: Green Mountain, above 450 m, 1974, L. Brown; Green Mountain, farm roadside above Red Lion, 700 m, 30 Oct. 1976; below Coronation Peak piggeries, 15 Nov. 1976, Q. Cronk. In addition to the New Zealand record mentioned above the rust species has been reported on Pennisetum spp . from Sudan, Ethiopia, Kenya, Uganda, Tanzania, Mozambique, Malawi and Chad (type locality), Nigeria, Ghana and S. Africa. It is also known from Australia and India. To our knowledge no rust fungus has previously been reported from the Ascension Island, and no doubt this one was introduced with the host . We are indebted to Mr Q. Cronk for sending us these specimens, to the late Dr C. E. Hubbard, Kew, for identification of the New Zealand grass, and to Dr G. B. Cummins, University of Arizona, Tucson, U.S.A., for verifying our identification as far as this was possible. REFERENCE

J. U.

(1977). Additions to the rust fungi of New Zealand. VI. New Zealand Joumal of Bot any 15,29-37·

DINGLEY,

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