In these GM oilseed rape plants a the new acyl-[ACP] thiosterase is
expressed that specifically catalyses the synthesis of the medium
chain fatty acids myristic and palmitic acids. These fatty acids
occur naturally in other plant oils used for human consumption
(e.g. coconut oil).
The modified oilseed rape plants were selected using the nptII-gene
product NPT. Hence the plants must be considered to be resistant
against antibiotics like neomycin and kanamycin.
In view of the proposed measures to minimise dispersal through
pollen or seed, the spread of the GM oilseed rape plants beyond the
trial area is not to be expected.
Summer oilseed rape is an annual, winter oilseed rape a perennial
plant. Following the generative phase the plant dies off; new
plants can only emerge from the seeds produced. If they become
buried deep in the soil and enter secondary dormancy, rape seeds
can persist in the ground for over 20 years.
Studies have shown that alterations in the fatty acid composition
of the storage lipids of the seeds can affect seed persistence in
oilseed rape. At the present time there are no experimental data
available on whether the myristic acid produced in the GM oilseed
rape plant seeds proposed for release affects the capacity of the
seeds to persist. However, the applicant assumes that under the
conditions found at the release site the GM seeds are disadvantaged
in comparison to normal oilseed rape seeds, since the seeds of the
transgenic lines contain 30 - 40% saturated fatty acids, whereas
oil from conventional oilseed rape plants contains approximately
90% unsaturated fatty acids. Saturated fatty acids have a
significantly higher melting point than unsaturated fatty acids and
are mobilised more slowly in our climate conditions due to the
relatively low germination temperatures.
The persistence of seeds from the GM oilseed rape and from
potentially occurring oilseed rape hybrids can be minimized by
taking appropriate measures after every harvest to ensure that any
seeds released are brought to germination during the same
vegetation period and any plants emerging from these seeds are
subsequently destroyed. These measures are planned for the proposed
experimental release.
During preparation of the soil for future planned agricultural use,
seeds from oilseed rape or oilseed rape hybrids that remain in the
soil despite completion of the above measures are brought close to
the soil surface where they can germinate. The resulting plants
will be identified and destroyed, either within the crop rotation
monitoring planned by the applicant or during the cultivation gap
(spanning a number of years) and post-trial monitoring required by
provision II.10. If GM oilseed rape plants or oil-seed rape hybrids
continue to appear during the final post-trial monitoring year, the
respective monitoring period will be extended by a further year .
The cultivation gap requirement ensures that any potential regrowth
of oilseed rape plants and oilseed rape hybrids can be identified.
The potential emergence of individual GM oilseed rape seedlings or
hybrids on or outside the release site after the end of the
post-trial monitoring period does not pose a risk with regard to
pollen transfer to other plants or long-term establishment.
Outside cultivated sites oilseed rape is only found as a weed in or
near areas where the crop is grown, e.g. on waysides and other
ruderal sites. Oilseed rape is not capable of establishing in
natural, intact plant communities. These GM oilseed rape plants are
not expected to develop modified plant socio-logical traits as a
result of the introduction of the ClFatB4 gene nor are they
expected to populate other biotopes.
Therefore, even in the event of the emergence of individual GM
oilseed rape seedlings and the possi-ble transfer of pollen to
non-GM plants, no long-term, sustainable spread of the GM oilseed
rape is expected. The temporal and spatial limitation of the
release is thus guaranteed.
Oilseed rape stocks are about two thirds self-pollinating and one
third cross-pollinating. The oilseed rape pollen is dispersed by
insects (particularly bees) and by wind. To minimise undesirable
foreign pollination in agricultural seed production, seed
legislation calls for isolation distances of 100 m for certified
seed and 200m for basic seed. A minimum separation distance to
neighbouring oilseed rape fields is set down in provision II.7. of
the decision on this application. However, it should be assumed
that to a limited extent oilseed rape pollen may be carried beyond
the isolation distance.
Pollination of individual flowers of non-GM oilseed rape would
result in the temporary appearance of isolated oilseed rape plants,
the seeds of which would exhibit an altered fatty acid profile.
This is not expected to pose a risk to the environment or to
agriculture. During extraction of the rapeseed oil from any seeds
that might emerge from the pollination of individual oilseed rape
flowers with pollen from the GM oilseed rape plants, the enzyme
acyl-[ACP] thioesterase would be separated from the oil along with
the rest of the proteins. The proteins would remain in the pressing
residue, the so-called "press cake", which is used in animal feed.
Myristic acid, the newly expressed fatty acid, and palmitic acid,
which occur in higher proportions in the seeds of these oilseed
rape plants, are already found in exist-ing products, some of which
are used for human consumption. Therefore, the potential
consumption of rapeseed oil with a higher myristic and plamitic
acid content or products made therefrom does not pose a threat to
human health.
Swede (Brassica napus var. napobrassica) belongs to the same
species as oilseed rape. It can be assumed that oilseed rape and
sweed are cross-compatible.
Swede is a biennial plant which develops a tuberous hypocotyl in
the first year, but only flowers in the second year. When
cultivated for sale and consumption the plants are harvested in the
first year. The possibility of fertilisation with pollen from GM
oilseed rape is given when swede is brought to flowering for the
purpose of harvesting seeds (e.g. for the cultivator's own
requirements). Although they belong to the same species, swede and
oilseed rape differ significantly in terms of morphology (oilseed
rape does not develop a tuberous hypocotyl). It can be assumed that
hybrids resulting from the pollination of swede by oilseed rape
pollen would be markedly different in appearance from swede. Since
untyp-ical plants would not be cultivated for the further
propagation of swede, GM hybrids are not expected to be consumed or
used for further seed production.
Several species in the Brassicaceae family are closely related to
oilseed rape; these are potentail crossing partners. Oilseed rape
(Brassica napus) is a hybrid of wild turnip (Brassica rapa) and
wild cabbage (Brassica oleracea) and is therefore, in principle,
cross-compatible with these species - with the following
limitations.
Experimental hybrids of Brassica napus and B. oleracea were
generated by extracting embryos from the ovules and regenerating
these to plants on culture media (embryo rescue). However to date
the spontaneous development of such hybrids under field conditions
has not been observed.
Winter turnip rape (Brassica rapa ssp. oleifera) is cultivated as a
crop plant for oil production and as a catch crop. Outside of
cultivated areas it is also found growing wild on sites influenced
by human ac-tivity (ruderal sites, waysides, field edges). Hybrids
of B. napus x B. rapa appear sporadically in oil-seed rape fields
if fertilisation with pollen from B. rapa took place when the
oilseed rape seeds were propagated.
With regard to the possible consequences of pollination of
individual flowers of non-GM winter turnip rape plants, the above
statements on oilseed rape apply correspondingly. In addition, the
fertility of primary hybrids of B. rapa and B. napus is generally
limited. They are anorthoploid and are character-ised by a marked
reduction in the function of the gametes resulting from irregular
meiotic chromosome distribution. The progeny of such gametes are
aneuploid; they are generally of low vigour and also display low
fertility.
Other Brassicacae, such as leaf mustard (Brassica juncea), black
mustard (Brassica nigra), white mustard (Sinapis alba), wild
mustard (Sinapis arvensis), species of common radish (Raphanus
sati-vus), wild radish (Raphanus raphanistrum) and shortpod mustard
(Hirschfeldia incana) are potential crossing partners for oilseed
rape. Because of the low chromosomal homology between these plant
species and oilseed rape, the above statements on Brassica rapa and
Brassica oleracea apply to an even greater extent to hybrids of
these plants and oilseed rape. Amphidiploid hybrids obtained by
ex-perimental crossing of oilseed rape with related Brassicacae
species represent the only exception. These hybrids, which probably
arise from unreduced gametes of the parent plants, exhibit only
slightly reduced pollen fertility. Even if isolated cases of
hybridisation between the GM plants and these spe-cies of
Brassicacae were to occur, it is highly unlikely that the genetic
material transferred to the GM plants would spread to into wild
plant populations.
With regard to all theoretically possible hybrids between the GM
plants and non-GM crop plants or wild plants, the ClFatB4 gene
would not cause the development of altered plant sociological
character-istics in these hybrids.
The genetically modified oilseed rape referred to in the proposed
field trial is not intended for use in foodstuffs or animal
feed.
The field trial aims at validating the expected effect of the
genetic modificaion under field conditions.
Field trial, not for human consumption or for feed purposes
An English summary of the notification including the risk
assessment of the notifier is available at the EU WebSNIF
internet-page of Joint Research Centre under notification number
B/DE/02/147 (see below)
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