Quality control
Before any seed is packed it is subjected to intensive quality tests. These tests are carried out by Rijk Zwaan in its own glasshouses and laboratory. The tests focus in particular on establishing germination rate/vigour, varietal trueness/varietal purity and the absence of any disease.
Germination
The quality of seed is determined largely by the way in which it germinates. A grower wants all seeds he has bought to germinate: all at the same time and all at the same rate.
Whether this is possible depends on germination energy, germination speed and germination vigour of the seed. Rijk Zwaan sows samples of all batches and records their germination behaviour. If germination energy, germination speed and germination vigour do not come up to expectations, the batch is rejected.
Causes of bad germination could be:
- the seeds are dormant
- the seeds are still immature
- the seeds have come from a bad production
Dormancy and immaturity may well be overcome and the batch may still be sold. Badly produced seed is destroyed immediately, however, and all efforts – from growing to final testing – will have been for nothing.
Varietal trueness and varietal purity
A customer must know that the seed he buys is seed of the variety he wants and that this applies to the whole batch. Rijk Zwaan sows a sample of each batch before selling it. This is tested for varietal trueness and varietal purity by means of a ‘grow-out’ or with molecular markers.
Seed pathology
During seed production, a crop can contract a disease. Some diseases can survive in or on seed. These infected seeds make them a source of infection which can cause a lot of damage. That is why Rijk Zwaan always checks each batch of seed on the possible presence of fungi, bacteria, viruses and nematodes. To this end, Rijk Zwaan has at its disposal numerous testing methods.