Book of Abstracts (PDF) - International Mycological Association

IMC7 Main Congress Theme II: SYSTEMATICS, PHYLOGENY AND EVOLUTION Posters
619 - Coevolution between fungus-growing termites and
Termitomyces fungi
D.K. Aanen 1* , P. Eggleton 2 , C. Rouland 3 , T. Guldberg-
Froslev 4 , S. Rosendahl 4 & J.J. Boomsma 1
1 Zoological Institute, University of Copenhagen,
universitetsparken 15, 2100 Copenhagen, Denmark. - 2 The
Natural History Museum, Cromwell Road, London, U.K. -
3 Laboratoire décophysiology des invertebrates, University
of Paris XII, Val de Marne 61, avenue du General Charles
de Gaulle, 94010 Creteil Cedex, France. - 4 Botanical
Institute, University of Copenhagen, Oster Frarimagsgade
2D, DK-1353 Copenhagen, Denmark. - E-mail:
dkaanen@zi.ku.dk
Termites of the exclusively Old World subfamily
Macrotermitinae live in an obligate symbiosis with fungi of
the genus Termitomyces (Basidiomycotina). Here we
present phylogenies of both partners in this symbiosis
(estimated using Bayesian analyses of DNA sequences).
Our sample consists of 43 colonies of termites and their
fungi (belonging to 32 termite species, covering 9 of the 11
genera) from three African and three Asian localities.
Fungal sequences were obtained using comb material,
basidiocarps and termite gut contents (using Termitomyces
specific primers). For information on the taxonomic
affiliation of the Termitomyces symbionts we also obtained
DNA sequences from herbarium specimens of seven
relatively well defined species. We show that the symbiosis
has a single African origin and that secondary
domestications of other fungi or reversals to a free-living
state have not occurred. Host switching at low taxonomic
levels is common and single termite species can have
different symbionts. This is consistent with fungal
reproduction, independent of termite reproduction
(horizontal transmission), which is inferred to be the
ancestral transmission mode. Specificity increases towards
the higher taxonomic levels and the four main clades of
fungus-growing termites are generally associated with
specific clades of fungi. The inferred patterns of coevolution
challenge the hypothesis that vertical
transmission is a prerequisite for maintaining advanced
mutualistic symbiosis.
620 - Species delimitation in the Puccinia striiformis
complex
M. Abbasi 1 , S.B. Goodwin 2* , M.S. Scholler 3 & Gh.A.
Hedjaroude 4
1 Plant Pests & Diseases Research Institute, Botany
Department, Tehran, Iran. - 2 USDA-ARS / Purdue
University, Department of Botany and Plant Pathology,
1155 Lilly Hall, West Lafayette, IN 47907-1155, U.S.A. -
3 Purdue University, Arthur and Kriebel Herbaria, 1155
Lilly Hall, West Lafayette, IN 47907-1155, U.S.A. -
4 Tehran University, Plant Protection Department, College
of Agriculture, Karaj, Iran. - E-mail:
sgoodwin@purdue.edu
188
Book of Abstracts
Puccinia striiformis (Uredinales), the cause of yellow rust
or stripe rust, is a species forming uredinia and telia on
various species of Poaceae. It is assumed to be
heteroecious, but the aecial host is not known. Currently,
two varieties, P. striiformis var. striiformis and P.
striiformis var. dactylidis are accepted by most authors. We
sequenced the variable internal transcribed spacer (ITS
1+2) region and the more conservative 5.8S gene of the
ribosomal DNA and found considerable differences among
specimens on Triticum (Triticae), Dactylis glomerata
(Poae) and Poa pratensis (Poae). These results correspond
with a previous isozyme phenotype study and also with
analyses of morphological features. Based on these
differences we suggest a three-species system including P.
striiformis on numerous hosts (mainly on Triticeae), P.
pseudostriiformis sp. nov. on Poa pratensis (Poae), and P.
striiformioides nom. et stat. nov. on Dactylis glomerata
(Poae).
621 - Nomenclatural and taxonomic status of some taxa
in Russula sect. Xerampelinae
S. Adamcík & P. Lizon *
Institute of Botany, Dúbravská 14, SK-842 23 Bratislava,
Slovakia. - E-mail: botupali@savba.sk
Numerous validly published names in agarics have not
been accepted by current authors. Due to short and
insuficient original descriptions and missing type
specimens their identity is doubtful. We have studied
members of Russula sect. Xerampelinae with greenish
pileipes those taxonomic delimitation and nomenclature are
confusing. Only three taxa in that group are clearly
delimited: Russula clavipes Velen., R. cicatricata Romagn.
ex Bon and R. schaefferi Kärcher. R. schaefferi differs in
having narrow terminal cels of generative hyphae in
pileipes and spores with long spines. R. clavipes and R.
cicatricata have terminal cells of generative hyphae in the
center of the pileipes inflated. Illustrations are available for
lectotypification (even Latin diagnoses are missing) of
Russula elaeodes and R. fuscoochracea R. Schulz. Later
name is superfluous (homonym of R. fuscoochracea
Velen.) but R. elaeodes seems to represent a distict taxon.
No type specimen was designated for R. barlae, R. fusca,
R. ochracea and R. olivascens and original descriptions
lack characters typical for the section. Another names, such
as R. citrinocincta, R. cookeiana and R. duportii need also
clarification. Complexe knowledge of the members of
Russula sect. Xerampelinae and consequent rejection of
several names are the only way how to stabilize the
nomenclature and the taxonomy of this section.