Handbook Part 2 - International Mycological Association

PS5-575-0841
Comparisons between the rust flora of Tibetan East Himalaya and the rust floras of India, Nepal and
Pakistan
J.Y. Zhuang
Institute of Microbiology, Academia Sinica, Beijing, China
The rust flora of Tibetan East Himalaya is characterized by the predominance of eastern Asian species. One hundred
twenty-nine species, amounting to 55.4% of the total known species in the region, are in common with the rust species
of Japan.
Tibetan East Himalaya adjoins Indian subcontinent and geologically is situated at the suture line connecting Indian
plate with Eurasian plate. The penetration of Indian-Malaysian floristic component to the Tibetan Himalaya is
unavoidable. The southern slope of East Himalaya has a climate effected deeply by the monsoon from Indian Ocean
and an abundant rainfall and a rich vegetation presenting sight of tropical rain forest are suitable for survival of rust
fungi from India. Seventy-four rust species, amounting to 31.8% of the total known species in Tibetan East Himalaya,
are in common with the rust species of India. It is worth mentioning that the primeval forest in the south to Medog
adjacent to India is still inadequately explored. The Indian rust flora is exceedingly luxuriant, containing a number of
phylogenetically primitive monotypic and small genera such as Arthuria, Chrysocelis, Hiratsukamyces, Masseeëlla,
Phragmidiella, etc. which are still not known in Tibetan East Himalaya. The distribution of their host plants suggests that
they are probably present in the tropical forest of the region and yet await the collectors.
Situated in Central Himalaya, Nepal is relatively similar to East Himalaya in forest vegetation. Comparison between the
rust flora of Tibetan East Himalaya and that of Napalese Himalaya shows some similarities. There are 61 species in
common, amounting to 26.2% of Tibetan East Himalayan total. The abundance of East Asian species suggests that the
Nepalese rust flora is a continuation of the East Himalayan rust flora.
Pakistan is of generally typical climate of subtropical steppe and desert. The Himalayas, Karakoram Mts. and Pamir
Plateau occupy the northern part of the country. The rust flora is quite different from that of the other parts of Himalaya.
There are about 200 known species belonging to some 20 genera. Only 36 rust species in Tibetan East Himalaya,
amounting to 15.5% of the total, are in common with the rusts of Pakistan. The tropical genera commonly found in East
Himalaya such as Gerwasia, Hamaspora, Maravalia and Ravenelia are rare or not found in the vast areas of Pakistan
inland. The connexion between the rust flora of Tibetan East Himalaya and that of Pakistan seems very weak.
PS5-576-0861
Metabolic and molecular biodiversity – evidence from a survey of New Caldedonian Fungi and New
Zealand Xylariaceae
M Stadler 1, JM Seng 3, S Buchet 2, HG Wetzstein 4
1 InterMed Discovery GmbH, BioMedizinZentrum, 44227 Dortmund, Germany, 2 BIOtransfer, 41 rue Emile Zola, -, 93100
Montreuil, France, 3 Laboratoire de Phytopathologie Moléculaire, Université de Paris-Sud , centre d’Orsay, Institut de
Biotechnologie des Plantes ( IBP ), 91405 Orsay Cedex, France, 4 Bayer HealthCare AG, Div. Animal Health, Research
& Development, 51368 Leverkusen, Germany
Much work has been dedicated to fungal biodiversity inventories, using traditional morphology, and meanwhile even
molecular approaches. The “innovative potential” of tropical fungi with respect to the discovery of novel secondary
metabolites and other innovative products for application in the Biotech industry was advertised repeatedly. However,
most of the lead compounds ever derived from fungi have been originally discovered from temperate species! There
are only few exceptions, such as nodulisporic acid from a group of pantropically distributed endophytes [1]. We have
attempted to correlate molecular and morphological data on species abundance vs. diversity of secondary
metabolite production in fungi from tropical and temperate climates and wish to present results of two different
projects.
a) A study on the xylariaceous genus Hypoxylon based on HPLC profiling [2] revealed an essentially redundant
secondary metabolism in many of their species, independent from differences in molecular and morphological traits.
In contrast, several apparently rare or endemic Hypoxylon spp. from New Zealand and the temperate Northern
hemisphere were found to contain unprecedented metabolites. Most of the New Zealand fungi studied that produce
specific metabolites were found from islands or other isolated areas.
b) During a survey of New Caledonian fungi from different habitats, carried out by a combination of molecular and
chemical methodology (comparison of ITS nrDNA and dereplication by HPLC profiling), we found that about 35 % of
the isolates contained several metabolites whose spectral data did not match with the entries of commercial
secondary metabolite databases, and with a proprietary HPLC-MS library. The ITS nrDNA and HPLC data correlated
very well; groups of strains with redundant DNA sequences generally showed similar HPLC profiles. It was occasionally
even possible to predict metabolite production by the molecular data and chemotaxonomic information. Some
strains from public collections whose sequences were retrieved from GenBank by BLAST searches showed similar HPLC
profiles as the wild type isolates.
=> Attaining quality assurance by molecular phylogeny appears ideal to identify redundancies prior to screening,
especially if and when microscopic/cultural characters do not allow for an effective morphological dereplication.
[1] J. Polishook et al. (2001) Mycologia 93: 1125–1137.
[2] V. Hellwig et al. (2005) Mycol Progr 4: 39–54.
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