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The AgBiotech Bulletin - Volume 1, Issue 5 (July 1993)
Published by Ag-West Biotech Inc.

1993 Crucifer Workshop Special Edition


Code: NL93013
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Presentations at the 8th International Crucifer Genetic Workshop
in Saskatoon cover a carefully selected range of issues which
affect the future of cruciferous crops such as canola, mustard,
broccoli, cauliflower and cabbage.

As a major source of oil, canola attracts the majority of
attention at the gathering. Four hundred scientists have come
together for this session.  They are all involved with crop
research which will have major influence on world health industry
and economics. Dr. Wilf Keller, workshop organizer and head of
Brassica Biotechnology for the Plant Biotechnology Institute of
the National Research Council says "The genetic work that
is being carried out today will shape the crops of the future in
a way that we have never seen before.  Many of the men and women
who are responsible for these breeding and biotechnological
advances are at this workshop.  The exchange of ideas and
knowledge possible at the meeting will help move us forward."


Extraordinary Potential in Cruciferous Plants

Canola dominates the stage at the Workshop. Dr. Keith Downey,
former head of the Oilseeds Section, at the Saskatoon Research
Station of Agriculture Canada summarizes the reasons for canola's
high profile in his presentation.

The Brassica oilseeds continue to increase in importance as a
source of high quality, nutritionally desirable edible oil and
high protein animal feed supplement.  In addition, it is rapidly
gaining favor as a suitable bio-diesel source and remains the
most promising plant group to meet the rapidly growing demand for
domestic edible oil in Asia and the Indian sub-continent.  Thanks
to advances in plant breeding techniques, including gene mapping,
and the application of biotechnologies to these responsive
plants, the horizon for the Brassica oilseeds is expanding in 
almost  every direction. Rapid advances are being made in oil
modifications for the edible and industrial market, enhanced
nutritional value of the meal, increased oil content, herbicide,
disease and insect resistance, pollen control systems and
molecular farming.  However, to reach those horizons and beyond
will require education of the producer and careful cultivation
and preparation of domestic and foreign customers.

Dr. Maurice Moloney says that plants could be a good inexpensive
source of proteins of high unit value. There are four technical
hurdles which need to be overcome if protein production for
plants is to be economically viable.  These challenges include:

*    the level of expression of recombinant protein
*    the location of the protein within the plant
*    the ability of the recombinant proteins to maintain its
     integrity
*    the ease of extraction and processing of the protein


He's investigating the possibility of using a unique class of
seed specific proteins called oleosins.  Properties of these
oleosins seem to have potential to overcome the four areas of
protein production concern.

Dr. Michael Dickson from Cornell University is enthusiastic about
the prospects for vegetable crucifer breeding particularly as
they become more popular among consumers in the western world.

The high nutritional value and anticarcinogenic beneficial
effects of cruciferous vegetables attract wide interest. 

Dr. Dickson is exploring hybrid systems for crops such as
broccoli, cabbage and cauliflower.  Genetic engineering
techniques are also being investigated for the control of disease
and insects. This may lead to a reduction in the use of chemicals
for pest control.

The vegetable breeding programs will benefit from the rapidly
expanding programs on oil seed crucifers.  The rate of change
will also depend on  how fast seed companies can incorporate
insect  resistance.

Nutritionally we may be able to add improved anticarcinogenic
factors and improve the nutritional level of such factors as
vitamin C as is now done in Germany, but also vitamin A and other
beneficial factors.


Symposium Trends

Molecular Characterisation of the Crucifer Genome

Extensive research into the use of molecular marker technology
is being conducted by a number of organizations. Once techniques
are refined so that critical plant characteristics can be linked
to particular parts of the chromosome, breeders and other
scientists will be able to use the information to develop
improved crops.  Researchers from the University of California,
the University of Wisconsin and Agriculture Canada report
industry advances in structure analysis and mapping.

Industry specialists from Intermountain Canola (IMC) and
Agrigenetics report that they are using molecular markers as
tools in their napus and rapa breeding programs.  Although the
approach is used sparingly in industry and only where there is
strong evidence that it will be the most effective and economical
tool for the job, fingerprinting technology has become part of
the industry science.

Companies are using the 'marker' technology to expedite the
development of rapeseed cultivators through: 

*    mapping of phenotypic traits
*    marker assisted selection
*    selection for desired genotype
*    reduction of linkage drag
*    genotypic fingerprinting of cultures

Intermountain researchers have identified molecular markers as
a major advantage in the development of fatty acid phenotypes
like low linolenic acid.

Dr. Robert Reiter, a molecular biologist with IMC says that the
primary focus on his organization is the development of healthier
oils.  "We are working to produce an oil from canola which does
not require hydrogenation." 

Although IMC has been most active in breeding and oil chemistry
research, developments are moving rapidly toward agbiotechnology
work. Dr. Reiter comments that biotechnology helps to expand the
portfolio of crucifer crops and will lead to improved nutritional
characteristics, better processing capabilities and reduced
production costs.


Strategies for Hybrid Seed Production in Cruciferous Crops

For many crop scientists, hybrid seed development is the ultimate
research challenge as they strive to find the most appropriate
male sterile system.  There has been no single method developed
which offers all of the answers to the complex challenge but
some organizations are working with very promising techniques. 
Plant Genetic Systems for example, has developed a 'pollen'
ablation system which is useful in both vegetable and oilseed
Brassica species.

Dr. Parker reports that the PGS team has created recombinant
genes that provide a tight control of male fertility when
they are expressed in transgenic plants.  The research results
indicate that genetically engineered male sterility and restorer
genes are widely applicable in Brassica species and should
facilitate the seed production of commercial hybrids.


Fatty Acid Modification in Oilseed Brassicas

The traditional markets for canola and rapeseed oil are expanding
in both edible oil and industrial uses.

According to presentations from researchers at the University of
Manitoba, the Saskatoon Agriculture Canada research station,
Pioneer Hi-Bred, the Plant Biotechnology Institute and Calgene,
the major emphasis in fatty acid research is on modification to
produce high erucic, low linolenic and high oleic acid oils.  It
appears that work on high lauric and high-stearate oil could
become commercial reality.

Calgene has progeny with high stearate acid content in field
tests in Canada, U.S. and Scotland.

Agriculture Canada has gene sources for the development of high
erucic industrial oil form as well as two species which have high
erucic acid and low glucosinolate content in the meal.

Pioneer Hi-Bred has developed a high oleic acid canola which is
currently being tested.

Dr. David Taylor of the NRC-Plant Biotechnology Institute says
that his group is working to genetically modify B. napus to
produce ultra high erucic rapeseed oils which can be used as
high-temperature lubricants and as inputs in nylon, industrial
coatings and plastic films. They are using a gene from meadowfoam
which can increase the production of erucic acid in B. napus.


Seed Quality Improvement in Oilseed Brassicas

Researchers continue to investigate the biosynthetic
pathways of glucosinolates.

The NRC-Plant Biotechnology Institute is working on yellow seeded
forms of canola which will have higher yields of high quality,
high oil seeds.  To support this goal Dr. G. Rakow reports that
researchers are working to identify glucosinolate-free forms of
B. rapa. In order to optimize the use of rapeseed as a food
commodity researchers and breeders are working to eliminate or
reduce undesirable traits.

Dr. H. Sorensen of the Royal Veterinary and Agriculture
University of Denmark reports that research into glucosinolate
biosynthesis and inheritance of glucosinolates in B. napus
continues. There is indication that specific genes have been
identified with glucosinolate content in B. napus seed.

Additional material by other presenters explored the expression
of:  modified proteins in canola meals, modification of phenolic
ester metabolism in crucifers and moderation of carbon allocation
to storage compounds in seeds.


Diseases in Crucifers

The NRC-Plant Biotechnology Institute (PBI) is employing
molecular marker technology to generate a better understanding
of canola diseases. Dr. David Taylor reports that his team has
developed a diagnostic test for seeds contaminated with blackleg. 
The test is faster and more simple than traditional methods.

In addition to this diagnostic development PBI researchers are
working with a novel chemical signal, phomalide, which is
released by blackleg fungus and the activities it seems to
engender.

Work is being done at the University of Toronto to identify and
analyze the mode of action of sclerotinia. The research group
will use the work to develop sclerotinia resistance in canola.

The Zeneca Seeds research team is assessing the potential of
introducing gene coding for an oxalate degrading trait in crop
species in order to confer resistance of oxalate producing
pathogens such as sclerotinia. Early findings indicate that the
process has positive results.

Phytogenetic analysis being carried out at the Saskatoon Research
Station of Agriculture Canada indicates that Alternaria brassica,
A. brassicicola and A. raphani (alternaria species) are closely
related and that the genus Alternaria is closely related to the
genus Pleospora.

Dr. R. Rimmer of the University of Manitoba notes that the
Brassica/Albugo (White Rust) host pathogen system provides a
model for studies into the genetic physiology molecular biology
and evaluation of host/parasite interactions.  A method has been
developed to explore resistance using this system.  A number of
studies are in progress.

Other presenters from University of Wisconsin - Madison, CPRO -
DLO in the Netherlands, the Asian Vegetable Research and
Development Centre in Taiwan and Nivot in Japan are researching
resistance in crucifer vegetables.  New approaches to genetic
analysis incorporating molecular markers and  classic
quantitative studies are allowing researchers to make significant
headway.  There are still challenges to be solved in identifying
and accessing sources for resistance qualities.

Insect Pests in Crucifers

Insect pests such as fleabeetles, diamond back moths, and  Bertha
army worms rank high among the threats to canola crop production. 
Research is being carried out on a variety of genetically
engineered techniques of insect control. The Winnipeg Research
Station of Agriculture Canada and Agrigenetics Research of the
U.S. are both investigating the use of Bacillus thuringiensis
(Bt) as a control measure in canola.

Agrigenetics is currently producing transformed rapeseed plants
with rebuilt genes targeted to various insect pests.

In addition, Dr. R. Broadway of Cornell University reports that
there are investigations underway which look at wax deposit on
leaves and characteristics of the chemical makeup of leaves which
affect insect feeding patterns.


Pest & Stress Interactions

A collaborative study between the Universite de Montreal and
University  of Laval is exploring the relationship between the
leaf chemistry of certain types of transgenic canola plants and
insect feeding behavior.  An additional finding in this study
indicates that certain transformed plants have reduced levels of
glucosinolate. This may eventually increase the value of canola
meal.

Dr. Susan Martin with the U.S. DA-ARS reports that research is
underway to explore biocontrol strategies for parasitic
nematodes.  Some metabolites in crucifer plants have been shown
to have potential to control nematodes.  A variety of studies
are being conducted to investigate this phenomenon more fully.

Dr. J. Singh of the Agriculture Canada Plant Research Centre
reports recent work in the identification and characterization
of freezing tolerance in B. napus.

A collaboration study by researchers from the University of
Alberta, the University of British Columbia and the Agriculture
Canada Plant Research Centre is focusing on alleviating the green
seed problem created by frost through the use of anti-sense RNA
technology.


Germ Plasm Development

Brassica crops display enormous diversity and are a source of
vegetables, fodder, condiments and oil.  An understanding of the
genetic potential of the wild relatives of this crop species is
critical for efficient long-term breeding programs.  Various
members of the wild types of brassica contain traits, such as
disease and insect resistance, which might be of value to
cultivated brassicas. Dr. S. Warwick reports that an Agriculture
Canada team is working to identify these characteristics.

Dr. R. Mithen reports that the John Innes Institute in the UK is
investigating the potentially valuable properties of wild
species.  He suggests that in addition to providing traits such
as disease resistance the broadening of the genetic base through
the introduction of wild material could be beneficial.

Dr. M. McFerson of the USDA located at Cornell University says
his team is exploring the use of molecular level diagnostics to
help characterize genetic identity, structure and relatedness in
germplasm accessions of common brassica species.  Ultimately such
an approach would greatly enhance conservation activities in
genetic resource collections of crucifers and other crops.

Dr. B. Roy at the University of California reports that genetic
diversity can be of value in preventing disease but that is not
the only influence which affects the severity of disease.  Other
factors such as host density and proximity to sources of
innoculum may overwhelm the role of genetic variation in limiting
disease.


Herbicide Tolerant Brassica

Weed control is an important aspect of canola production.  In
recent years there has been a great deal of research activity in
the area of herbicide tolerant canola.

Government, universities and industry have all been active in
seeking specific tolerance solutions.

Dr. M. Oelck with Hoechst, Canada outlines special steps in the
breeding process which facilitated the rapid developments in 
transformation of microspore derived embryos.

Monsanto reports that current lines of Roundup (TM) tolerant
canola exhibit no damage at extended use rates and stages, and
only slight maturity delay at twice the intended use rate.

Field testing of transgenic plants has been carried out since
1988.  In 1993 application for 485 trials have been approved. 
An Agriculture Canada presentation highlights the regulatory
protocol for field evaluation of transgenic plants for herbicide
tolerant plants.



For additional information or correspondence contact:
Dr. Murray McLaughlin, President
Ag-West Biotech Inc.
222 - 111 Research Drive
Saskatoon, Saskatchewan
Canada   S7N 3R2
phone:  (306) 975-1939
fax:    (306) 975-1966


The AgBiotech Bulletin
is published by
Westcross House Publications
#201 - 617 8th Street East
Saskatoon, Sk.   Canada  S7H 0R1

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