BEN # 259

Adolf Ceska aceska at victoria.tc.ca
Tue Oct 24 04:52:46 EST 2000


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BBBBB    EEEEE    NN N N             BOTANICAL
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No. 259                              October 24, 2000

aceska at victoria.tc.ca                Victoria, B.C.
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 Dr. A. Ceska, P.O.Box 8546, Victoria, B.C. Canada V8W 3S2
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_PTEROSPORA  ANDROMEDEA_: MORPHOLOGICAL AND MOLECULAR ASSESSMENT
   OF MYCORRHIZAE FROM PLANTS GROWING  IN  A  CONIFEROUS  FOREST
   ECOSYSTEM IN CENTRAL BRITISH COLUMBIA
From: Catherall J.M., H.B. Massicotte, B.W. Young,
   L.E. Tackaberry, & K.N. Egger
   c/o Jen Catherall <cather0 at hotmail.com>

[This  is  a  summary  from  a  poster presented at the Canadian
Botanical Association Annual Meeting in London, Ontario, in June
2000. The poster that I produced received  the  Ian  and  Sylvia
Taylor Award for best student poster. This project is part of my
undergraduate  thesis project that is still underway and will be
completed in June 2001. - Jen Catherall,  University of Northern
British Columbia, Prince George, BC, Canada V2N 4Z9]

_Pterospora andromedea_ Nutt.  (pinedrops;  Ericaceae,  Monotro-
poideae) is a curiously impressive epiparasitic species that has
attracted  numerous ecological and morphological investigations.
This achlorophyllous species, the only member of its genus,  has
a  complex  mode  of  nutrition,  receiving  photosynthates from
neighbouring trees via shared fungi.

To explore the  mycorrhizal  associations  within  its  northern
range,  plants  were  sampled from 4 sub-boreal forest locations
near Prince George, BC. Site-associated  trees  varied  but  in-
cluded  _Pinus  contorta_,  _Picea_  spp., and _Populus tremulo-
ides_. A minimum of 5 root clusters per location were  collected
over  10  weeks  (June  to  August,  1999).  Both  epigeous  and
hypogeous  sporocarps  of  the  _Suillus_-_Boletus_-_Rhizopogon_
group  found  within  close  vicinity of the sampled plants were
also collected.

Mycorrhizae were assessed morphologically (light microscopy) and
by molecular analysis (PCR-RFLP and DNA sequencing). All methods
showed that individual  root  clusters  (often  several  hundred
tips)  consisted  of  fungal  monocultures. Only one fungal mor-
photype  was  characterized  for  all  tips;  this   mycorrhizae
produced  a white mantle (sometimes mauve to darker blue), short
bristle-like verrucose cystidia, no clamps, and rhizomorphs.

The three restriction endonucleases (AluI, HinfI and RsaI)  used
to  cleave the PCR product for RFLP analysis showed no variation
between the fragment patterns for the samples. DNA sequencing of
the 5' end of the 28S region of the ribosomal RNA  gene  of  the
_Pterospora  andromedea_ and _Pinus contorta_ root tips, as well
as the hypogeous sporocarp, resulted in a highly similar partial
sequence alignment. Submission of the fungal sequences  to  Gen-
Bank  suggests  that  these  fungi  closely resemble _Rhizopogon
subcaerulescens_ (I.D. #AF071534).

These data are still being analysed but early results  from  the
investigation  support  findings  by  Cullings  et  al.  (1996).
_Pterospora andromedea_ appears to be uniquely specialized  with
the  _Rhizopogon  subcaerulescens_ group across widely disparate
regions of North America, including  its  northern  range.  This
study  also  provides  increased  evidence into the probable ec-
tomycorrhizal linkage between  _Pterospora  andromedea_,  _Pinus
contorta_  and  _Rhizopogon  subcaerulescens_.  The  mycorrhizal
specialization exhibited by _Pterospora andromedea_ may directly
impact the ability of this mycoheterotrophic plant to link  with
its  autotrophic host(s) and ultimately its survival in changing
forest ecosystems.

Reference:

Cullings, K. W., T.M. Szaro, & T.D. Bruns.  1996.  Evolution  of
   extreme  specialization  within  a lineage of ectomycorrhizal
   epiparasites. Nature 379(6560): 63-67.


PROTECTION OF WETLANDS IN CANADA
From: Clay Rubec [Clay.Rubec at ec.gc.ca]

Wetlands in Canada are managed very differently  than  in  other
developed  nations,  particularly  in  the  United States. While
American experience has been strongly oriented  to  a  regulated
permitting  system  and protection based on litigation, Canadian
federal and provincial management to date has a strong focus  on
voluntary,  non-regulatory  action  supported by policy based on
sound scientific advice.  The  Government  of  Canada  and  four
provinces  (Alberta,  Saskatchewan,  Manitoba  and Ontario) have
adopted  wetland  management  policies  articulating  goals  and
strategies  for  cooperation and stewardship. This is not to say
regulatory actions are also not in use, in  Ontario  and  Prince
Edward  Island  for example provincial law regulates the use and
development in and around wetlands.

In all provinces and territories  in  Canada  a  wide  range  of
wetland  conservation  programs  and  other regulatory tools are
also in place that assist in protecting wetlands and encouraging
an overall no net loss perspective. These are  summarized  in  a
recent  publication  entitled "_Wetlands and Government_" avail-
able  from  the  North  American  Wetland  Conservation  Council
(Canada),  Suite  200,  1750 Courtwood Cres., Ottawa, ON K2C 2B5
(e-mail: nawcc at igs.ca) or on line at http://www.cws-scf.ec.gc.ca
- see publications section of this Environment Canada web site).

Why this voluntary-policy approach? Experience  in  Canada  sug-
gests  organizations  feel there are circumstances where a regu-
lated system is appropriate as no other options exist.  In  some
geographic  areas  (e.g.,  the  Fraser Lowland and southeast On-
tario) too many wetlands are degraded and too  few  options  for
voluntary  action  exist. However, in much of Canada a voluntary
stewardship approach offering landowner incentives  and  support
may  be  more  effective.  Despite over 20 years of costly, time
consuming litigation and regulation across the USA, wetlands are
still being lost. Canadians have benefitted from  watching  this
USA experience and seek a better more successful approach here.

A  major  difference also lies in the constitutional authorities
across the USA versus Canada. In the USA, the federal government
may regulate all wetlands over  a  minimum  size  using  federal
water  course protection legislation and other mechanisms. Small
wetlands and  those  not  associated  with  federally  regulated
waters  are under state authority in most cases. Such is not the
case in Canada, where most  wetlands  as  a  provincial  natural
resource  are  owned  and managed under provincial jurisdiction.
Only wetlands on federal lands, and in the Northern  Territories
generally  lie  under  direct  federal  management.  The federal
government has laid out its commitments for wetlands through the
Federal Policy on Wetland Conservation since 1991 and the  Guide
for Federal Land Managers under this Policy (1996).

Contact:  Clayton  Rubec, A/Chief Habitat Conservation, Environ-
   ment Canada, Ottawa, ON K1A 0H3.


BOOK REVIEW: BRYOPHYTE BIOLOGY
From: Wilf Schofield [wilfs at interchange.ubc.ca]

Shaw, A. Jonathan &  Bernard  Goffinet  [eds.]  2000.  Bryophyte
   Biology.  x+476  p.,  Cambridge  University Press, Cambridge.
   ISBN 0-521-66097-1 [hard cover] Price: US$100.00, ISBN 0-521-
   66794-1 [soft cover] Price: US$35.95.

   Available from:
   Cambridge University Press
   The Edinburgh Bldg., Cambridge CB2 2RU, United Kingdom
   http://www.cup.cam.ac.uk
   40 West 20th Street, New York, NY 10011-4211, USA
   http://www.cup.org

This book presents a valuable summary of  current  knowledge  of
selected  aspects  of  bryophyte  biology.  It  is  an essential
reference for  bryologists  and  invaluable  to  those  pursuing
specialized  topics  in  the  biology  of bryophytes. Few of the
contributors have attempted to write for a novice; most articles
are dense with specialized terminology. A  glossary  would  have
helped all readers immeasurably.

The contributions include articles on anatomy , development, and
classification of hornworts (Renzaglia & Vaughn), morphology and
classification   of   the  Marchantiophyta  (Crandall-Stotler  &
Stotler), morphology and classification of the  mosses  (Buck  &
Goffinet),   origin   and   phylogenetic  relationships  of  the
bryophytes (Goffinet), chemical  constituents  and  biochemistry
(Mues),  molecular  genetic studies of moss species (Cove), con-
trol of morphogenesis in bryophytes (Christianson),  physiologi-
cal  ecology  (Proctor),  mineral nutrition, substratum ecology,
and  pollution  (Bates),  peatlands:  ecosystems  dominated   by
bryophytes (Vitt), role of bryophyte-dominated ecosystems in the
global carbon  budget (O'Neil),  population  ecology, population
genetics,  and  microevolution  (Shaw),  and  bryogeography  and
conservation of bryophytes (Tan & Pocs).

Illustrations   are   few  and  reproduction  of  half-tones  is
generally poor,  often  resulting  in  grey  blurred  images.The
illustration  of  _Polytrichum  piliferum_,  for  example, is so
blurred that it is impossible  to  determine  the  species,  and
acrocarpy  is  not clearly represented because attachment of the
sporophytes is obscure; the illustrations  for  pleurocarpy  are
highly successful.

It  is  disappointing to see, yet again the terms haplolepideous
and diplolepideous used when it is apparent  that  haplolepidous
and diplolepidous are meant.

In  summary, this book contains extremely useful articles on the
current status of selected topics in bryology.  It  is  probable
that  the  classification systems are premature, based on inade-
quate data; these systems will be vastly altered when those data
become available. Still, they represent useful summaries.  As  a
reference  book for students who have had education in fundamen-
tal bryology, it will be highly useful, but for  beginning  stu-
dents, it is far too specialized.

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