Download Genetic improvement of grapevine: WHY?

Genetic improvement of
grapevine: WHY ?
Melané A Vivier
Institute for Wine Biotechnology
Stellenbosch University
Why am I here trying to answer
this question?
Because we, together with a large international
community, supported by numerous industries and
other funding agencies, are trying to ask and
answer scientific questions regarding the most
important fruit crop of the world, namely Vitis
vinifera (grapevine)
We focus on understanding the genetic potential of the
species, using molecular and cellular biology tools
We have developed (bio)technologies that can lead to
genetically improved grapevines, aligned with industry
needs
We have applied for an experimental field trial with transgenic
grapes, which sparked much debate
Media reports
SA Scientists seek go-ahead for
field trials of GM grapes (Cape
Times)
Protests at Stellenbosch transgenic
grapevine experiment (Grape news)
Genetically
modified wine on
the cards (Cape
Times)
Wingerdinstituut se GM proef sal ‘n
eerste wees (Die Burger)
Frankenfoods’ from a
madman’s lab. Gene grapes
no barrel of fun (Son)
So, are we interested in “contaminating” the
environment, creating “weedy” grapevines or
causing harm to wine-drinking customers, or
the wine-industry in general?
•
•
•
•
Aims of the programme
To know more about grapevine and how it
“works”……
To find solutions to support environmentally
friendly production…..less pesticides 
To find solutions to the impact of the changing
climate…..stress-tolerance 
To find novel ways to improve quality and
wholesomeness
Towards environmentally friendly
production and stress tolerance…..
A grape gene (Vvpgip), present in multiple copies protects against fungal
pathogens
A grape gene (VvNCED), protects against water stress
The process involved to generate a transgenic
grapevine and the evaluations needed
Somatic embrogenesis
Cryopreservation
Genetic transformation
Regeneration
Photographs obtained from the work of Dr. Khrishnan Vasanth, IWBT
The process and evaluations
(a)
GRAPEVINE
TISSUE CULTURE
Globular
Heart stage
Isolation of
anther
filaments
Embryogenic
callus line
Torpedo
Induction of
somatic
embryogensis
1-2 Years
Grapevine flower
Cotyledonary
Somatic embryos : target material for grapevine transformation/regeneration
(b)
GRAPEVINE
TRANSFORMATION
Agrobacterium-mediated or biolistic bombardment of somatic embryo cultures
Selection of transformants
1-2 Years
Regeneration of putative transgenic plantlets
Hardening-off of plantlets
(c)
EVALUATION
OF TRANSGENICS
Confirmation of transformations (PCR, Southern, Northern analysis)
Evaluation of stable expression
Greenhouse trials
Fieldtrials
Evaluation for stable expression, phenotype, ampelography,
viticultural analysis, analysis of fruit and/or wine produced
depending of industry targeted.
5-8 Years
The specifics about the contained
experimental vineyard
• Why did we apply?
– To obtain a mature, fruit-bearing GMO vineyard for scientific
purposes
• What would it contain and where will it be?
– Grapevine plants with inserted reporter and antibiotic genes (the
latter as selectable marker) alongside non-transgenic grapevines
– The transgenic material will be grafted on non-transgenic
rootstocks on the Welgevallen experimental farm of Stellenbosch
University
• Objectives?
– To assess the reporter gene activity over several seasons and to
assess the agronomical performance of the transgenic material
alongside conventional grapevines
The experimental vineyard
• On Welgevallen experimental farm
• 930 m2, fenced, restricted admission
• 238 US Vit 8-7 (NON-TRANSGENIC)
Rootstocks planted – 100 used for first
trial
• Virus-free (molecular analyses)
• Trellis and irrigation systems for
Chardonnay and Sultana established
• Structure for super fine netting to cover
trial
• Normal viticultural practices
Transgenic grapevine plants
• 100 plants in first round trial
– 6 Lines Chardonnay, 6 lines
Sultana, 4 controls of each
– 5 plants of each line
• Random block design
• Monitoring: at least five seasons
• Management plan included
Public notification
• Public notification with details of proposed field
trial:
– IWBT and DVO staff and students
– SU Research Development
• SU management
• Ethical committee
–
–
–
–
IWBT Website
SU Bulletin
Winetech and DFPT – to industry role players
Local media:
• Eikestadnuus
• Die Burger
• Cape Argus
• The wording of the notification was not optimal…..
Reaction to public
notification
• 2 Official objections within allowed period (Biowatch
and African Centre for Biosafety); 1 Subsequent
objection from Biowatch
• Several email messages from the public
• Replies to all official objections, a further press
release in collaboration with SA Wine Industry and
significant e-mail correspondence
• Interviews with the media:
–
–
–
–
Newspapers
Electronic journals / newsletters
Magazines
Radio stations (SABC)
Not factual reporting in all cases!
General concerns
General aspects:
1.
2.
3.
General anti-GMO
Environmental contamination / Biosafety
Antibiotic Resistance Genes: nptII
Wine-industry specific aspects:
1.
2.
Activities done without support of SA wine
industry
Impact of the possible commercialisation of GM
grapevine and wine
Understanding the specifics about Vitis
will clarify many misconceptions
• Grapevines are not
indigenous to South
Africa
– The first Vitis
species arrived with
the settlers!
• Grapevines have no
close relatives in South
Africa, meaning that
there is no plant
species with which it
could interbreed
Misconceptions………
Pollen flow and seed dispersal
• Domesticated grapevine
flowers are functionally
bisexual and largely selfpollinated
• Grapevine is not planted
from seed; it is vegetatively
propagated
– In SA certified plant
material is strictly
controlled in the supply
chain
Misconceptions……….
Seed dispersal and seedling volunteers
• Grapevines are planted in “manicured” vineyards which are
intensively worked
• Seedling volunteers are scarce, very visible and routinely
removed through normal viticultural practices
Understanding the specifics about Vitis
will clarify many misconceptions
• The concept of “true-to-typeness” (in viticultural
terms)……
– In the wine industry, the varietal names and characteristics are
important marketing attributes
– The viticultural performance, as well as the varietal characteristics
in the vineyard and in the resulting wine are important factors to
consider
– This has a direct impact on the prospect of GMO vines and wines
and therefore needs to be assessed rigorously
• Scientific advances provides the possibility to also perform
genetic and transcriptomic profiles of GMO vines in comparison
with non-transgenic vines
General concerns
Environmental contamination
•
Possible release of transgenes into the environment
–Pollination of grapevine: largely by self-pollination, no wild
relatives of grapevine in SA, no related plant species to hybridise
• Flowers in the trial will be covered with bags
–Seed dispersal: Seedlings do not normally survive in
uncultivated habitats; Volunteer seedlings controlled by routine
viticultural practices.
• The trial site will be covered with a superfine net and fruit
will be bagged
–Soil contamination: The transgenic plants will be grafted on
non-transgenic rootstocks, frequency of horizontal gene transfer
from plants to microorganisms very low under normal
circumstances, transgenes already present in very large
amounts in environment, transgenes do not give competitive
advantage.
• Rigorous management of fallen leaves and other plant
material; Environmental impact monitored
Perspectives
The challenge is perhaps to strike a balance
between strict control and monitoring of
GMO materials and their release, while not
hampering the progress of science
Thank you