Book of Abstracts (PDF) - International Mycological Association

IMC7 Monday August 12th Lectures
phylogeny using genera in the Halosphaeriaceae as
examples of initial concepts and current perceptions.
54 - Mangrove mycology in South East Asia: Who,
what...and what else ?
T.K. Tan
Department of Biological Sciences, National University of
Singapore, Science Drive 4, Singapore 117543, Singapore.
- E-mail: dbstantk@nus.edu.sg
One of the earliest records of marine fungi in south east
Asia was that of Jones (1968), who reported Lulworthia
floridana and Halosphaeria quadric-cornuta on drift wood
collected in Singapore. Interest in marine mycology in the
region was nurtured at IMC3 in Tokyo in 1983. As
mangrove swamps constitute the extensive and
characteristic coastal vegetation in this part of the world,
subsequent post-IMC3 works focused primarily on the
marine fungi in mangrove habitats. The first few papers
were that of Gacutan and Uyenco (1983; Philippines),
Kohlmeyer (1984, Thailand), Tan (1985, Singapore and
Malaysia), Koch (1986, Thailand), and Jones and Tan
(1987, Malaysia). Since then, intense interest and studies
have yielded a wealth of information on the biodiversity of
mangrove fungi in the region, with more than 100 new
species and genera described. Apart from biodiversity, the
proximity and accessibility of mangroves facilitated
ecological studies undertaken to account for the observed
occurrence, abundance and distribution of these fungal
species. These included studies on fungal succession,
vertical distribution, substrate specificity, and to a lesser
extent, fungal interactions. Molecular taxonomy has also
been studied in the last few years. Three IMCs later, how
do we take stock of the progress in mangrove mycology ?
There is certainly scope for further work on biodiversity
and ecology. The question is: how can studies on mangrove
fungi create a greater impact on life ?.
55 - Diversity and phylogeny of Halophytophthora
(Oomycetes)
A. Nakagiri
Institute for Fermentation, Osaka, 17-85, Juso-honmachi
2-chome, Yodogawa-ku, Osaka 532-8686, Japan. - E-mail:
nakagiri-akira@ifo.or.jp
Halophytophthora species are straminopilous oomycetes
inhabiting marine and brackish water environments as a
first colonizer on the submerged fallen leaves. Fourteen
species and two varieties have been described so far mainly
from mangrove environments. They show wide variation in
ecology and characters of asexual reproduction. For the
purpose of investigating the phylogenetic relationship with
other straminopiles and clarifying the species level
taxonomy of this diverse group, 18S rDNA, D1D2 region
of 28S rDNA and ITS1-5.8S rDNA-ITS2 were sequenced
in 58 strains of Halophytophthora species and analyzed
phylogenetically with other related oomycetes. The
analyses revealed 1) the most species of Halophytophthora
nested in the Peronosporomycetidae clade, but H. spinosa
positioned apart from the main group but close to
Sapromyces (Rhipidiomycetidae), which suggests at least
removing H. spinosa to other (new) genus, 2) the
Phytophthora-Peronospora clade nested within the main
group of Halophytophthora as a sister group of H. vesicula
complex, which includes H. vesicula and other
morphologically similar species, 3) the species in the main
group of Halophytophthora formed several clades, each of
which corresponds to its specific character of asexual
reproduction, 4) looking at the phylogenetic relationship
between Phytophthora and Halophytophthora, the tree
showed that the terrestrial or freshwater parasites might
have evolved from the marine or brackish water saprobes.
56 - Thai lignicolous aquatic fungi: From river to the
sea
S. Sivichai * , J. Sakayaroj & I. Chatamala
BIOTEC-Mycology Laboratory, National Center for
Genetic Engineering and Biotechnology, National Science
and Technology Development Agency, 113 Pahonyothin
Rd., Klong 1, Klong Luang, Pathumthani 12120, Thailand.
Over the past 10 years our knowledge of Thai aquatic fungi
has increased dramatically and with the description of
many new taxa. The only previous records were those of
Tubaki et al. (1983) on Ingoldian fungi. Although the
major focus has been on their ecology, recent studies
examines their molecular phylogeny, especially genera not
assigned to an order or family for example Bathyascus,
Torpedospora (Ascomycetes), Dendryphiella and
Sigmoidea (anamorphic fungi). Currently some 600 higher
aquatic fungi have been recorded for Thailand.
57 - Marine fungi: A time to redefine?
E.B.G. Jones
BIOTEC, 113 Pahonyothin Road, Klong 1, Klong Luang,
Pathumthani 12120, Thailand. - E-mail:
bhgareth@yahoo.com
Many workers have tried to characterize physiologically
and ecologically what is a marine fungi? Over 1,000 fungi
have been recorded from marine habitats and they appear
to be well adapted for life in this environment. However,
some species have also been recovered from freshwater
habitats and this raises the issue of how we define this
unique group. Recently, molecular studies have
demonstrated that members of the Halosphaeriales
originated from a terrestrial ancestor, rather than evolution
from ancestral marine taxa. Similarly, a number of marine
bitunicate ascomycetes have been shown to group with the
terrestrial Pleosporales. It is therefore time to reconsider
Book of Abstracts 19