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New Zealand Journal of Botany abstractB97050 Received 17 July 1997; accepted 24 November 1997
Rust fungi of New Zealand--An introduction, and list of recorded speciesE. H. C. MCKENZIE
Herbarium PDD
Abstract An overview of the rust fungi (Basidiomycota,
Teliomycetes, Uredinales) is presented as an introduction towards a new rust
mycoflora for New Zealand. All species recorded from New Zealand are listed,
together with details on their host plants, a reference to the first New
Zealand record of each unique rust/host combination, and a separate
alphabetical list of host plants and the rust fungi which parasitise them. New
Zealand has a depauperate rust flora consisting of 234 recorded species, of
which 54% are native. Of 22 genera recorded from New Zealand only five genera
(Hamaspora, Kuehneola, Phragmidium, Puccinia,
Uromyces) and three form genera (Aecidium, Caeoma,
Uredo) contain native species. Only five genera (Phragmidium,
Melampsora, Puccinia, Uromyces, Uromycladium) and two
form genera (Aecidium, Uredo) are represented by more than two
species. Melampsora contains mainly adventive species; approximately
half of the Phragmidium, Puccinia, and Uromyces species
and all the Uromycladium species are adventive. Some 95% of the
Uredo species and all the Aecidium species are native. Only eight
native rusts have spread to exotic hosts; Uredo puawhananga commonly
infects some exotic, cultivated Clematis species, while Puccinia
lagenophorae is sometimes troublesome on cultivars of Bellis
perennis. None of the 17 exotic rusts infecting native plants is of
economic or conservation concern.The widespread rusts in New Zealand are often
adventive species. Only 5% of adventive rusts are confined to the South Island,
but 30% are confined to the North Island. This inequity probably reflects the
warmer conditions in the north, and the fact that adventive species are often
of tropical origin. Of the native species, 34% occur only in the South Island
and just 14% are restricted to the North Island. Since 1945, on average, more
than one new adventive rust has been found per year. Most of them are of
northern temperate origin, but often considered to be introduced from Australia
by trans-Tasman airflows. |