So that we can always offer our customers the best young plants, we have opted for our own in-house quality assurance. Our quality assurance is fundamentally a multi-level
system that covers all stages of micropropagation: starting with the first plant material,
which we get from a (new) variety, then to the starting material up to the actual
micropropagation and also beyond that to the finished young plant, which bears fruit
This article is intended to refer exclusively to the internal quality of the plant material.
We will write a separate article about the quality assurance of the actual young plant.
A new variety comes to our company
As mentioned at the beginning, we start our quality assurance before the actual
micropropagation. With the first material, which we obtain from a variety or selection,
we attach great importance to already tested material that is virus-free. This material is
usually provided by the breeders. If no tested material is available, we also rely on
untested material and then perform the appropriate tests ourselves. As soon as we get
plant material of new varieties/selections, this material is planted out or potted in our
variety testing garden.
Our variety testing garden
Picture: Variety testing garden at our location in Strullendorf
In our variety testing garden there are all of the varieties that are being propagated, the
new breeding selections that are in the test/trial phase, but also varieties that are now
no longer being propagated. We then have all these plants produce fruits, so that we
can look at and judge the fruits. This is because our requirement is that we want to see a
fruit at least once before the beginning of the micropropagation in order to determine
the value of a variety or selection. The fruits are looked at from a pomological point of
view and described to check whether a variety has really bred true. At the same time,
the inner quality of the fruits is also checked, whether it may have deformed fruits or,
more importantly in the case of the raspberries, if they have crumbly fruits. If
undesirable plants are discovered, they will be destroyed immediately. Of course, the
flavour of the fruits of a variety is evaluated because that matters with our varieties; the
taste has to be convincing. Also, in the variety testing garden, even before the plants
start to flower, the first testing for viral diseases is carried out because some viruses are
transmissible via pollen.
If everything is fine with this pomological inspection, the micropropagation will begin at
the beginning of the next growing season. In addition to the fruits and the state of
health, of course, the growth character of a variety or selection is examined and the
general plant health is also evaluated. This is because it does not help if the best-tasting
variety is marketed, but the plants have little chance of survival in the home garden.
The starting material and the actual beginning of micropropagation
The material for the start of micropropagation is obtained in different ways depending
on the genus. Either it is obtained directly from the examined plants from the variety
testing garden or from plants that are situated in a weather protected location during
the vegetation period, so that there are fewer infections when they come into the
laboratory. A very common method is also the formation of so-called "sister plants", in
which these plants are obtained either by cuttings, root cuttings or rooted runners.
Depending on the genus, material for the micropropagation of the respective sister
plants is usually obtained two years in a row before they are renewed. This ensures that
always the pomologically checked material is propagated.
Again, immediately before the micropropagation, a virus test for relevant viruses is
again performed. This is done so that we can ensure that only healthy plant material is
used for propagation.
In addition, the dual control principle applies when harvesting the sister plants. This
ensures that the later young plants can be traced back through all propagation steps to
a single plant in the variety testing garden.
Picture: plants during micro-propagation in a climate-room
Another important element of our quality assurance takes place directly in the
laboratory during micropropagation. Thus, the plant material used for micropropagation
is renewed in regular cycles. Each material is only used in the laboratory for a certain
amount of time or for a certain number of propagation steps before it is renewed. In
this way we prevent the alteration of the propagation material by too many propagation
steps. We also work extremely cautiously with plant hormones to prevent mutations and
other changes in the plant.
The finished young plant
Picture: sellable young plant after successful propagation
Even after successful establishment of the micropropagated young plants and after
commercial propagation, there is still a final stage of quality assurance. Young plants are
taken from the inventory on a random basis. These are potted and then allowed to bear
fruit in the variety testing garden. Thus, even after successful propagation, we still have
the opportunity to check the young plants for varietal identity and pomological quality.
Ultimately, we want to know for sure that what we put into the propagation system at
the beginning also comes out.
Click here for more information
Would you like more information, an individual consultation or information about
Click here for the complete 2019 catalogue, which can be downloaded.
If you have specific questions, please do not hesitate to contact our customer service,
where you can also spontaneously place an order.
And of course we are always there for you via telephone.
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