see e.g. Huitenga:

ZAADVASTHEID, trueness-to-type; zie ook RAS- ECHTHEID.
ZAADVEREDELAAR, plant breeder.
ZAADVEREDELING, plant breeding; seed im­ provement.
ZAADVEREDELINGSBEDRIJF, plant breeding station (farm, establishment).
ZAADVERMEERDERING, seeds multiplication.
ZAADVERMEERDERINGSBEDRIJF, seeds multiplication farm.
ZAADVERSPREIDING, dispersal of seeds, seed dispersal.

– Huitenga, T.: Nederlands-Engels Woordenboek voor Landbouwwetenschappen (Numij Leiden).

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Note added at 25 mins (2017-04-12 21:51:27 GMT)
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see also: https://www.google.co.uk/search?rlz=1C1CHBF_en-GBGB733GB733&... (Google search for: "seed multiplication" "zaadvermeerdering")

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Note added at 27 mins (2017-04-12 21:53:33 GMT)
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Nog eens 6 miljoen EUR wordt vastgelegd in contracten met de Voedsel- en Landbouworganisatie voor een programma voor zaadvermeerdering, dat in samenwerking met de regering ten uitvoer zal worden gelegd.

=

An additional EUR 6 million is being contracted with the Food and Agriculture Organisation for a Seed Multiplication Programme to be implemented with the government.

src: CELEX General, financial and institutional matters.tmx

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Note added at 29 mins (2017-04-12 21:54:46 GMT)
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"Seed multiplication

Farmers are encouraged to take up seed production by being provided with seeds for this specific purpose. Most often, these seeds are sourced from the community seed bank. Interested farmers then multiply these seeds to return to the bank, which distributes them to members outside the community or village, with profits from the endeavour being used to expand the seed bank.

Seeds produced are also sold through the farmers’ society of Janadhanya, which works in collaboration with community seed banks and farmers to further develop farmer initiatives within an area.

Seed multiplication is important in that it helps enrich the biodiversity of a local area by making available many indigenous seed varieties to farmers who hitherto had no access to the seeds. It is also an income generating scheme where individual farmers are compensated for their efforts in seed production."

(http://www.greenconserve.com/content/seed-multiplication )

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Note added at 33 mins (2017-04-12 21:58:58 GMT)
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– Huitenga, T.: Nederlands-Engels Woordenboek voor Landbouwwetenschappen (Numij Leiden):

VERMEERDERAAR:
(v. rassen) multiplier;
propagator;
//the// farmer who multiplies the seeds //of-//.

VERMEERDEREN:
increase;
augment;
(v. zaaizaad en pootgoed) multiply;
zich - , increase;
grow;
(v. dier, plant) multiply;
zij - zich snel, they multiply rapidly.

VERMEERDERING:
increase;
augmentation;
(v. zaaizaad en pootgoed) multiplication;
goedgekeurde (erkende) - , approved m.;
- door, (ook) grown from //stolons, tubers//.

VERMEERDERINGSBEDRIJF:
multiplication farm

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– Huitenga, T.: Nederlands-Engels Supplement voor Landbouw- en Milieuwetenschappen (Numij, 1996):

: VERMEERDERAAR,
- van jonge hennen, pullet grower

: VERMEERDERING,
- met zaad of knollen, seminal propagation;
vegetatieve vegetative propagation

: VERMEERDERINGSBEDRUF, multiplying farm

: VERMEERDERINGSKAS, propagating house