Book of Abstracts (PDF) - International Mycological Association

IMC7 Main Congress Theme III: PATHOGENS AND NUISANCES, FOOD AND MEDICINE Posters
stimulated fungi growth and polysaccharides production.
The best polysaccharide producers, I. levis and T.
mesenterica, were cultivated in BioFlo Fermentor 2000
(New Brunswick, USA). In this case yield of crude proteinpolysaccharide
products reached 23 and 27 g l -1 ,
respectively. Data on the dynamic of fungi growth in
fermentor indicate that in the culture of T. mesenterica
biosynthesis of polysaccharide parallels to fungus biomass
growth, while in the case of I. levis polysaccharide
synthesis mainly occurs in the later logarithmic phase of
growth.
916 - Mechanism of wilting in oak mortality in Japan
caused by Raffaelea quericivori
T. Yamada 1* , M. Yamato 2 , D. Sakaue 1 & K. Suzuki 2
1 Experimental Station at Tanashi, The University Forests,
The University of Tokyo, Midori-cho 1-1-8, Nishitokyo,
Tokyo 188-0002, Japan. - 2 Graduate School of Agricultural
and Life Sciences, The University of Tokyo, Yayoi 1-1-1,
Bunkyo-ku, Tokyo 113-8657, Japan. - E-mail:
yamari@uf.a.u-tokyo.ac.jp
Mass mortality of oaks (mainly Quercus serrata and Q.
crispula) has been appeared along the Japan Sea since
1980's. Blockage of xylem sap ascent induced by infection
of a fungus Raffaelea quericivori, which is vectored by
ambrosia beetle Platypus quercivorus, is considered to
have close relationship with this mortality of oaks. Lower
stems of Q. serrata and Q. crispula seedlings were
inoculated with R. quercivori. Dye treatment revealed that
blockage of sap-flow occurred only around the inoculation
points. Symptoms during wilting after the R. quercivori
inoculation and those after cutting of lower stem were
similar. Further, supplying water into stem lengths cut from
upper half of the seedlings just after the appearance of
wilting also delayed the further development of wilting in
both of them. Water conductivity in the stem was measured
with a high pressure flowmeter (HPFM) after the fungus
inoculation onto Q. crispula seedlings, which survived
after the inoculation. A parameter of chlorophyll
fluorescence, Fv/Fm, decreased slightly in several
seedlings. Conductivity was not changed in the upper part
of the seedlings, though conductivity aroud the inoculation
points was conspicuously reduced in fungus-inoculated
seedlings, especially ones with lowered Fv/Fm. Our results
suggested that upper part of the seedlings was not directly
affected by the fungal inoculation, and that wilt was
induced by the blockage of sap ascent around the
inoculation point.
917 - Penicillium fungi from Picea glehnii seeds protect
the seedlings from damping-off
K. Yamaji * , Y. Fukushi, Y. Hashidoko & S. Tahara
Department of Applied Bioscience, Faculty of Agriculture,
University of Hokkaido, Kita-ku, Sapporo, 060-8589,
Japan. - E-mail: Keiko.Yamaji@joensuu.fi
276
Book of Abstracts
We have postulated that germinating seeds and seedlings of
Picea glehnii might be protected from pathogens by seedepiphytic
fungi that produce antimicrobial compounds. We
screened seed-epiphytic microorganisms that produced
antibiotics against pathogenic Pythium vexans by the agaron-paper
method. Of the 149 isolates, 13 fungi showed
high antifungal activities and they were identified as
Penicillium fungi. Three isolates (P. cyaneum, P.
damascenum, and P. implicatum) showed high antifungal
activity and they produced patulin, citrinin, palitantin and
frequentin, respectively. In the co-inoculation test of three
Penicillium species and P. vexans to P. glehnii seedlings,
the number of surviving seedlings which were inoculated
with P. vexans 5 days after pre-inoculation with P.
damascenum increased compared with those inoculated
with P. vexans alone. Dense mycelial growth of P.
damascenum was observed microscopically around the
roots of the inoculated seedlings. Furthermore, the
antifungal and phytotoxic compound citrinin produced by
P. damascenum was detected as a component released
around the roots of the normally growing fungusinoculated
seedlings. We proposed two possible
mechanisms for the protection of P. glehnii seedlings by P.
damascenum from P. vexans; first, chemical protection by
an antibiotic agent, citrinin produced by P. damascenum,
and second, the occupation of the space around the P.
glehnii roots by the P. damascenum mycelia.
918 - Growth inhibition for wood decaying fungi by
lichen mycobionts
Y. Yamamoto 1* , M. Komine 1 , K. Hara 1 , S. Doi 2 & K.
Takahashi 3
1
Akita Prefectural University, 241-7, Kaidobata-nishi,
2
Shimoshinjo-nakano, Akita, Akita, Japan. - Akita
Prefectural University, 11-1, Kaieizaka, Noshiro, Akita,
Japan. - 3 Meiji College of Pharmacy, 2-522-1, Noshio,
Kiyose, Tokyo, Japan. - E-mail: yyamamoto@akitapu.ac.jp
About 400 strains of lichen-derived cultures induced
natural thalli and spores are maintained in our laboratory
and we previously indicated that they showed several
biological activities. In natural conditions, lichens may
oppose mushroom on the bark. Screening of growth
inhibition of two wood decaying fungi, Trametes
versicolor (L. ex Fr.) Pilat and Fomitopsis palustris (Berk.
et Curt.) Gilbn & Ryv. in 46 strains of lichen mycobionts
cultured. Two cell-aggregates of each mycobiont strain
were placed oppositely on agar-plates of malt-yeast extract
medium, glucose peptone medium and potato dextrose
medium in a Petri dish and pre-incubated at 20C in the
dark. After a month, one agar block of malt-yeast extract
medium on which a wood decaying fungus grew was
inoculated in the center of the agar-plate on which its
mycobiont grew and maintained at 20C in the dark. After a
week, inhibitory effect on growth of a fungus by lichen
mycobionts was judged from the extent of its inhibition
circle. Three mycobionts of Acarospora fuscata, Arthonia
cinnabarina and Ramalina exilis inhibited the growth of
both fungi. The growth of T. versicolor was inhibited by
mycobionts of Stereocaulon sorediiferum and Dibaeis