BEN # 205

Adolf Ceska aceska at VICTORIA.TC.CA
Fri Oct 16 03:46:33 EST 1998


                                                   
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No. 205                              October 16, 1998

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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IN VITRO FERTILIZATION OF CONIFERS:
   HOW TO BYPASS SEXUAL BARRIERS IN BREEDING
From: Patrick von Aderkas <pvonader at uvvm.uvic.ca>

Drs. Danny Fernando, John Owens and Patrick von Aderkas (Univer-
sity of Victoria) are happy to announce the first conifer embryo
produced  by  in  vitro  fertilization.  This  work,  which  was
recently reported  in  Theoretical  and  Applied  Genetics  (see
below),  was  the culmination of three years of work testing and
refining conditions in the search for the best way to grow  male
and  female  structures  of Douglas fir in Petri dishes. The as-
sisted conception was brought about when germinated pollen  tube
penetrated  the  eggs,  and released gametes, one of which fused
with the egg nucleus. Early stages  of  embryo  development  oc-
curred  in  vitro.  The  proof of these events was provided in a
series of sections of plastic-embedded material. We have yet  to
produce a tree, but the prospect of consummating sexual union in
vitro  offers  intriguing possibilities, especially in regard to
hybridization.

This was borne out by a subsequent study, to be published in TAG
(in press) by Nicole Dumont-BeBoux and coworkers in which it was
shown that there is no barrier to delivery  of  gametes  between
any  of the genera of the Pinaceae attempted. These included: i)
Sitka spruce into either noble  hybrid  larch,  Douglas  fir  or
western  white pine; ii) western white pine into Douglas fir; or
iii) western larch into western white pine. Pollen tube penetra-
tion occurred in all crosses and was  verified  by  histological
study.  Gamete  delivery occurred in the spruce/larch cross. The
conclusion from our work is that prezygotic sexual  barriers  to
reproduction do not exist in vitro. In vitro fertilization could
be  used  to  cross  species  that are not currently possible to
cross by conventional  breeding  methods.  It  also  provides  a
method  to  study  the  processes  of  pollen attraction, gamete
delivery and fertilization  in  controlled  environments.  Even-
tually,  we  should  be able to elucidate some of the underlying
mechanisms in gymnosperm reproduction.

Fernando, D.D., J.N. Owens, & P. von  Aderkas.  1998.  In  vitro
   fertilization   from  co-cultured  pollen  tubes  and  female
   gametophytes  of   Douglas   fir   (Pseudotsuga   menziesii).
   Theoretical and Applied Genetics 96: 1057-1063.

Dumont-BeBoux,  N.D.,  M.  Weber,  Y.  Ma, & P. von Aderkas. (in
   press).  In  vitro  pollen-megagametophyte  interactions   of
   conifers.  Theoretical and Applied Genetics 96: [accepted May
   1998]

   Dr. Patrick von Aderkas
   Graduate Centre for Forest Biology
   University of Victoria
   Victoria BC Canada V8W 3N5
   pvonader at uvvm.uvic.ca
   telephone: 1 250 721 8925
   FAX: 1 250 721 7120


ECOLOGICAL RESTORATION OF WETLANDS
From: Summary of Bruelisauer & Kloetzli (1998)

The article defines current technical terms used in the field of
restoration ecology and reviews restoration efforts in  restora-
tion of wetlands:

The  main  steps  in  restoring  species-rich  oligotrophic  wet
meadows on formerly fertilized grassland or arable land are  the
removal  of  excessive  nutrients, the correction of water table
and the re-introduction of species.

Restoration of ombrogenous bog depends  on  the  successful  re-
establishment  of  suitable  hydrological  conditions which will
often give rise to a spontaneous recolonization by  typical  bog
species;  details  of the artificial re-introduction of Sphagnum
species are also given.

In restoring riverine  ecosystems,  for  example  by  recreating
meanders,  apart  from  controlling flood hazards, consideration
will have to be given primarily to a variable design but  conse-
quences  on  the sediment transport should be carefully studied.
Vegetation can in most cases  be  left  to  natural  succession,
whereas  providing  unhindered  up- and downstream migration and
resting places for animals is an important issue.

The paper cites about 130 references related to this topic.

Bruelisauer, A. & F. Kloetzli. 1998.  Notes  on  the  ecological
   restoration  of  fen  meadows,  ombrogenous  bogs and rivers:
   definitions, techniques, problems. Bulletin of the Geobotani-
   cal Institute ETH (1998), 64: 47-61.  ["ue'  stands  for  "u"
   with an umlaut, the same with "oe"]

Dr. Alfred Bruelisauer studied at the University of British
Columbia with Dr. Garry  Bradfield.  His e-mail address is
alfred.bruelisauer at bd-pla.sg.ch


DR. CHRIS PIELOU'S FRESH LOOK AT WATER - BOOK REVIEW
From: Adolf Ceska <aceska at victoria.tc.ca>

Pielou,  C.E.  1998.  Fresh  Water. University of Chicago Press,
   Chicago.  275  p.  ISBN  0-226-66815-0  [hard  cover]  Price:
   US$24.00
   
   Ordering  information:  The University of Chicago Press, 5801
   South Ellis Avenue, Chicago, IL  60637  -  Fax:  773-702-9756
   http://www.press.uchicago.edu/

I  first  met Dr. Pielou in Victoria the mid 1970's when she was
invited to participate in a conference on mathematics  in  biol-
ogy. I vividly remember her lecture. Early in the morning before
the  lecture,  Chris Pielou went to the beach and picked several
species of seaweeds that she used in her  lecture.  Mathematical
applications  become  real  and  we,  the audience, were able to
relate abstract topics with  biological  objects.  We  all  were
impressed  how  clearly Dr. Pielou could communicate complex and
complicated ideas.

Dr. Pielou's demonstrates this quality in her recent book "Fresh
Water." In twelve chapters, Chris Pielou follows the water cycle
and all its stages. Rivers, lakes, underground and  soil  water,
water  in  plants,  frozen water, and water in wetlands, are all
subjects covered in Dr. Pielou's book. The book is an  excellent
synthesis  of  physical  geography,  soil  science, climatology,
hydrology, hydrobiology, plant physiology, and all other  fields
that relate to water.

The book describes "natural history" of water. It provides a key
to  the  understanding of many processes and features around us.
Dr. Pielou's writing style is  clear  and  captivating  and  the
"Prologue"  is a literary masterpiece in its own merit. The book
has plenty of unobstructive  footnotes  and  numerous  reference
citations. The book contains all, or almost all, what each of us
should  know  about water. Get the book and read it! You will be
glad you did.


HERBARIUM TYPE SPECIMENS IN THE NETHERLANDS ON A WEB SITE
From: Peter van Welzen <welzen at rulrhb.leidenuniv.nl>
        abbrev. from TAXACOM <taxacom at cmsa.berkeley.edu>

The database, funded by the Netherlands Science Foundation (NWO)
and produced with  the  package  BRAHMS  (Denis  Filer,  Oxford,
England),  combines  all  known type specimens of the four Dutch
herbaria: Amsterdam (AMD), Leiden (L), Utrecht (U), and Wagenin-
gen (WAG). This type of cooperation among herbaria is unique, as
is the fact that digital  images  are  available  of  most  type
specimens.  The  database  presently  holds  40,000  records and
30,000 images.

Visit HTTP://RULRHB.LEIDENUNIV.NL (or http://132.229.92.132/)

This netsite, produced by the Expert Centre for Taxonomic  Iden-
tification, ETI, Amsterdam, opens with a menu. The first choice,
'search the database', provides a form from which very versatile
queries  can  be  made. Plant names can be used as key words, as
well as geography, vernacular names, collectors, etc.  The  hits
are  presented in a spread sheet, arranged alphabetically by the
accepted name; basionyms are shown in the  right  hand  columns.
Double  clicking  on  a name will provide full label details and
show a photo of the type specimen(s).  Double  clicking  on  the
photo will provide an enlarged image on your screen.

The  main  menu also provides an option to order a CD-ROM of the
complete  database  (with  only   thumb-nail   images   of   the
specimens).  It  is also possible to order CD-ROMs with a subset
of the database and with high resolution photos.

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