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Health: Plant diagnosis

Diagnosis

Do you have a problem with your plants but have no idea what it is? The Diagnostics team can examine it for symptomatic material. They will produce a diagnosis based on your sample. As an international industry, new plant diseases are a regular occurrence in the horticulture sector. A plant that doesn’t grow disrupts the crop, and this impacts on your production and sales. Our Research & Development team works closely with specialists from the Netherlands and abroad.

Procedure

A diagnostic test determines which plant disease you are dealing with. There may also be a technical cultivation problem. Tests for frequently requested diagnoses such as TSWV, INSV, PepMV, CyMV and ORSV are always available. We also have a range of other tests available which enable us to produce a good diagnosis.

Take a sample or send an entire plant to our laboratory in Roelofarendsveen. We will start our investigation more or less as soon as we receive it. You will then receive your diagnosis result by email as soon as possible.

Requirements for submission

Instructions for taking samples

  • Take samples from a spot where the new symptoms are visible. It is often not possible to run laboratory tests on plants that have died off completely.
  • Take a sample before any pesticides/crop protection agents are applied. Pesticides can destroy or mask the symptoms caused by pathogens and interfere with the laboratory tests.
  • If the symptoms are unclear, send us the entire plant.
  • Where symptoms are unclear, or in the case of a rare plant, please also send us part of a healthy specimen. Pack the healthy sample separately and indicate on the label that it is healthy material.
  • If it is impossible to send a sample immediately, keep it cool. Never place samples in direct sunlight.

Instructions for packaging samples

  • Make sure leaves and flowers are not contaminated by any soil or growing media accompanying the samples. Enclose the roots in a separate bag with an elastic band around the stem.
  • Wrap the whole plant in paper to prevent it from drying out and rotting. The paper regulates moisture levels in the plastic bag. Use dry paper.
  • Affix a sticker with sample information on the packaging.
  • Do not use sample information stickers to seal the package.
  • Wrap the entire plant in plastic to prevent the spread of diseases.
  • Affix the order form in an envelope to the outside of the packaging.
  • Keep in mind that parcel delivery services may handle boxes roughly. Boxes should therefore be well filled.

Instructions for completing the order form

  • Enter the correct name and address on the order form.
  • Provide as much information as possible about the sample; this helps us produce a diagnosis more quickly.
  • If you have any digital photos of the material, you can email them to us.

Shipping address for samples for diagnosis:

Naktuinbouw
Diagnostics Team
Sotaweg 22
2371 AA Roelofarendsveen, NL

Fee
In our Price list Laboratories 2024 you will find details of the fees for the various tests we can perform for you in a range of areas.

Frequently asked questions (FAQ)

Samples can be sent by PostNL to:

Testing Laboratory
Attn. Laboratories Administration
P.O. Box 40
2370 AA Roelofarendsveen, NL

Diagnostics
Naktuinbouw
Attn: Diagnostics
Sotaweg 22
2371 AA Roelofarendsveen, NL

Variety Tracer
Naktuinbouw
Attn: Variety Tracer
P.O. Box 40
2370 AA Roelofarendsveen

When sending the samples with a courier service, or in case of large quantities of samples (e.g. on a pallet), please use the visiting address:

Testing Laboratory
Naktuinbouw
Attn: Laboratory Administration
Sotaweg 22
2371 GD Roelofarendsveen

Diagnostics
Naktuinbouw
Attn: Diagnostics
Sotaweg 22
2371 GD Roelofarendsveen

Variety Tracer
Naktuinbouw
Attn: Variety Tracer
Sotaweg 22
2371 GD Roelofarendsveen

Samples can be received between 8:00-17:30, from Mondays to Fridays.

Bioassays
Samples may be sent to:

Naktuinbouw
Tienrayseweg 9a
5961 NK Horst

  • Take samples from a spot where the new symptoms are visible. It is often not possible to run laboratory tests on plants that have died off completely.
  • Take a sample before any pesticides/crop protection agents are applied. Pesticides can destroy or mask the symptoms caused by pathogens and interfere with the laboratory tests.
  • If the symptoms are unclear, send us the entire plant.
  • Where symptoms are unclear, or in the case of a rare plant, please also send us part of a healthy specimen. Pack the healthy sample separately and indicate on the label that it is healthy material.
  • If it is impossible to send a sample immediately, keep it cool. Never place samples in direct sunlight.

A submission form downloaded from the website. Samples submitted from outside the EU must be accompanied by a phytosanitary certificate or DOIV.

You can find this form on the website. There are three different types:

A phytosanitary certificate is sometimes required for samples submitted from outside the EU. If it is not possible to request a phytosanitary certificate, you can request a special, accompanying letter (DOIV) on the website.

We advise you to send plant samples (perishable material) without symptoms on Mondays or Tuesdays. Plant samples with symptoms can be sent from Mondays to Thursdays. This will avoid samples being left in the post over the weekends and not being stored in the correct conditions. Samples sent on these days will also arrive in time for testing.

Seed samples can be sent every day of the week.

A registration form must be filled in first so we can enter the necessary company details in our system. 

It is also important to send an order form with the samples. This form is also on our website.