Monitoring throughout all production steps

To qualify for certification, the seedlings must comply with the rules and standards applicable to French production. The seedling production is subject to official inspections at all production steps.

Certification steps

Certification is carried out by:

  • Soil analysis before planting
  • Seedling inspections
  • Progeny controls
  • Post-harvest batch controls.

All these control operations lead to inspection reports and computer records.

At the end of this long process, the certification procedure ends with the tamper-proof sealing of the seedling package and the official label. The label guarantees control and provides information on the characteristics of the seedling batches. This allows them to move freely within the European Union. It also provides a tracking system that will help track the history of the product should a problem arise.

Quality controlled production

Inspections and information collection are carried out by the Official Quality and Control Department (SOCFrance) at all steps of potato seedling production: inspection admission, crop registration, plot inspection, batch inspection and finally certification.

Production rule prerequisites

  • Inspection admission: Authorization to produce for professional operators who distribute or place certified potato seedlings on the market. This authorization is granted by SOCFrance, after a technical investigation on the skills, the specific equipment level for the production of potato seedlings and the organization to ensure tracking.
  • Declaration of any production crop to SOCFrance. The crop declaration includes all the information about the production of certified seedlings: area, location, producer identity, batch number of mother plants, etc.
  • Plot free of quarantine organisms: Systematic soil analysis before planting to verify the absence of cyst nematodes (Globodera rostochiensis and Globodera pallida).
  • Isolation: Isolation must be identified between the different plant productions and must be at least 10 m away from any other potato crop
  • Minimum rotation of 4 years (3 years without potato).

Crop inspection

On behalf of SOCFrance, the inspectors carry out thorough checks on each seedling production plot, from sprouting to foliage damage.

For each production class, they check the compliance of the crops with sanitary and varietal standards.

They record all the results of their inspection on an inspection form with all the identification elements of the crop: visit dates, ratings for each criterion, classification, etc.

Applicable standards (% of seedlings affected)

Seedling categoryPre-basic seedlingsBasic seedlingsCertified seedlings
French classesPBTCPBSSEEAB
Varietal purity
(% impurity)
Rhizoctonia (Rhizoctonia solani)055551010
Non-rising or stunted seedlings07777710
PSTVd Viroid0000000
Virus TSWV0000000
Candidatus Phytoplasma solani (Stolbur)0000000
Candidatus Liberibacter solanacearum0000000
Epitrix cucumeris, Epitrix similaris, Epitrix subcrinita et Epitrix tuberisAbsence
Quarantine pests (such as Clavibacter sepedonicus, Ralstonia solanacearum, Synchytrium endobioticum, etc.):No tolerance allowed

Progeny controls (preculture)

Shortly before harvesting, representative samples of tubers produced in each plot are taken for several tests, mainly to determine the amount of viruses and to check for the absence of quarantine bacteria (Clavibacter sepedonicus, Ralstonia solanacearum).

For this purpose, lab analyses are carried out and the tubers are also germinated in a greenhouse for pre-cultivation, of which the resulting young seedlings will be visually analyzed by inspectors.

This step allows the final classification of the crops.

Applicable standards (% of seedlings)

Seedling categoriesPre-basic seedlingsBasic seedlingsCertified seedlings
French classesPBTCPBSSEEAB
Varietal purity000.
Viruses (PVY, PVX, PVM, PVS, PVA, PLRV)00.50.512510
Non-viral leaf deformities1122255

Batch controls

Each batch can only come from a crop that has been accepted through growing inspections and progeny control.

Each batch is visually inspected by an inspector for compliance with sanitary standards and tuber presentation. Should there be any doubt regarding pest identification, tests may be requested.

The inspection results are reported on a digital inspection form and will determine the final class of the seedlings to be certified.

Maximum contents in percentage of tuber weight

Pre-basic seedlingsCertified basic seedlings
French classesPBTCPBS, SE, E, A, B
1) External defects (deformed and injured tubers)033
2) Wilted tubers (including silver scurf symptoms)00.51
3) Dry and wet rots00.20.2
4) Common scabies*055
5) Powdery scabies00.20.2
6) Rhizoctonia**055
Total tolerance for items 1 to 656
Soil and foreign bodies111
Viruses inducing superficial tubercular necrosis00.10.1
Pest attacks (slugs, moles, flea beetles): Tubers with more than 10 holes or 3 holes of 5 mm or more in depth are counted044
Damage caused by cooling accidents022
Candidatus Liberibacter solanacearum000
Ditylenchus destructor000
Tomato spotted wilt virus (TSWV)000
Doryphore (Leptinotarsa decemlineata)Free tubers
Quarantine pests (such as Clavibacter sepedonicus, Ralstonia solanacearum, Synchytrium endobioticum, Meloidogyne chitwoodi and M. fallax, etc):No tolerance

*: tubers affected on a surface greater than one third

**: tubers affected on a surface greater than 10%

Batch certification and labelling

Once the checks have proved that all the regulatory conditions have been met, the potato seedling batches can be certified in the category and class that match the number of reproduction generations and the quality grade defined.

Certification is achieved by issuing and attaching an official label to each potato seedling package.

Each certified batch is recorded on a computer with all the related information (batch number, quantity, number of packages, number of labels attached, variety, size, etc.). This data ensures perfect tracking of the production history and the analyses carried out.

To go further...

The certification label, guarantees the seedling's quality


Learn about the certification framework and objectives


Discover how the industry works