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BEN # 205
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No. 205 October 16, 1998
aceska@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@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@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@bd-pla.sg.ch
DR. CHRIS PIELOU'S FRESH LOOK AT WATER - BOOK REVIEW
From: Adolf Ceska <aceska@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@rulrhb.leidenuniv.nl>
abbrev. from TAXACOM <taxacom@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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Submissions, subscriptions, etc.: aceska@victoria.tc.ca
BEN is archived at http://www.ou.edu/cas/botany-micro/ben/
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