Certified Seed Potatoes - Requirements & Definitions |
Prepared Pursuant to M.S. 21.112
Summary of Certification Requirements
- All potatoes planted within a farming operation must be approved for certification and entered for inspection.
- All equipment and storage facilities within the farming operation must be used only for certified seed potatoes.
- Each seed field must undergo at least two inspections during the growing season.
- Storage facilities and equipment used for grading and handling seed potatoes must be cleaned, sanitized and inspected at least once a year.
- No bacterial ring rot may be found on the farming operation to qualify for Generation, Primary Foundation or Foundation status.
- The zero tolerance for bacterial ring rot means that no observed amount is allowed during inspection. The discovery of a single plant in the field or a single tuber in storage infected with bacterial ring rot shall cause rejection of the field or lot. The absence of a finding shall not be construed to mean that the field or lot inspected is free from the disease or disease causing agent.
- Certification requirements are not complete on any lot of seed potatoes until it has been properly graded, identified with official tags or official bulk certificates, and has passed official grade inspection.
- Final grading inspection and tagging is under the supervision of Federal-State inspectors and a certificate of inspection must accompany each shipment.
Winter Test
In order to help determine if any late season spread of certain virus diseases has occurred, all fields of Generation, Primary Foundation and Foundation class seed are sampled at harvest for additional testing during the winter. Minnesota's winter test standards require that there be no more than one half of one percent of any or all virus diseases, and no spindle tuber or chemical damage detected in the sample.
Limited Generation Certified Seeds
Limited Generation certified seed potatoes must originate from pathogen tested in vitro plantlets and may be replanted for certification only a limited number of years. The classification of a Limited Generation seed lot changes each year that it is in the field, going sequentially from Generation 1 through Generation 6.
Classification Sequence:
Year in Field |
Seed Class |
Requirements |
|
Pre-Nuclear |
Greenhouse produced from pathogen tested stock |
First |
Generation 1 |
Field Grown Source is PN Virus tested, Winter tested |
Second |
Generation 2 |
Seed Source is G1. Winter tested |
Third |
Generation 3 |
Seed Source is G2. Winter tested |
Fourth |
Generation 4 |
Seed Source is G3. Winter tested |
Fifth |
Generation 5 |
Seed Source is G4. Winter tested |
Sixth |
Generation 6 |
Seed Source is G5. Winter tested |
Disease Tolerances
|
Generation |
|
1 & 2 |
3 |
4 |
5 & 6 |
Severe Mosaic |
0.50% |
0.50% |
0.50% |
0.50% |
Leafroll |
0.50% |
0.50% |
0.50% |
0.50% |
Total; of above |
0.50% |
0.50% |
0.50% |
0.50% |
Other viruses |
0.50% |
0.50% |
0.50% |
0.50% |
Varietal Mixture |
0.00% |
0.00% |
0.10% |
0.20% |
Bacterial Ring Rot |
0.00% |
0.00% |
0.00% |
0.00% |
Spindle Tuber |
0.00% |
0.00% |
0.00% |
0.00% |
Conventional Certified Seed
Conventional certified seed potatoes are initiated by clonal selection and the tuber unit technique on a primary foundation seed farm. Seed produced from a tuber unit plot is classified as Primary Foundation 1. The following year, Primary Foundation 1 seed is planted to produce Primary Foundation 2 seed. The seed then leaves the primary foundation farm and goes to a foundation seed farm where it is increased as Foundation class seed. Seed lots not meeting Primary Foundation or Foundation requirements are classified as Certified.
Disease tolerances:
|
Primary Foundation |
Foundation |
Certified |
Severe Mosaic |
0.50% |
0.50% |
1.00% |
Leafroll |
0.50% |
0.50% |
1.00% |
Total; of above |
0.50% |
0.50% |
1.00% |
Other viruses |
0.50% |
0.50% |
0.50% |
Varietal Mixture |
0.00% |
0.10% |
0.20% |
Bacterial Ring Rot |
0.00% |
0.00% |
0.00% |
Spindle Tuber |
0.00% |
0.00% |
0.00% |
Grade Requirements
The BLUE tag is issued on lots that have met all field and storage inspection requirements as well as standards higher than the U.S. No. 1 Seed Grade for size, condition and physical defects.
The YELLOW tag is issued on lots that have met the same certification requirements as blue tag, however, there is a higher grade tolerance for certain physical defects and mechanical injury.
The WHITE tag is issued on lots meeting the same certification requirements as yellow tag, except that grade is according to agreement between buyer and seller as to size and certain defects.
Seed Lot Classification
Seed lot classifications shown in this directory are based only on field inspection results. Final classification is contingent upon a tuber sample being submitted and passing the winter test.
Key to Abbreviations and Terms
Lot = A field designation assigned by the grower for identification and record keeping purposes.
* = Indicates a field was tested for Potato Virus X and showed no more than 3% infection.
PN = |
Pre-Nuclear |
G1 = |
Generation 1 |
G2 = |
Generation 2 |
G3 = |
Generation 3 |
G4 = |
Generation 4 |
G5 = |
Generation 5 |
G6 = |
Generation 6 |
FG = |
Field Generation |
FY = |
Years in Field |
PF1 = |
Primary Foundation 1 |
PF2 = |
Primary Foundation 2 |
F1 = |
Foundation 1 |
F2 = |
Foundation 2 |
C = |
Certified |
CPB = |
Colorado Potato Beetle |
PLRV = |
Potato Leafroll Virus |
PVY = |
Potato Virus Y |
A variety may be protected by the Plant Variety Protection (PVP) Act. Buyers should validate the status of the variety from the vendors and variety owner.
Disclaimer
A certification does not represent a warranty of any kind, expressed or implied, including merchantability, as to the quality of the crop produced from the certified seed potatoes. A certification represents only that the seed potatoes were produced, graded, sacked or placed in bulk, and inspected in accordance with Minnesota Rules Parts 1555.6720 to 1555.6950.
Notice
Beginning with the 2011 seed potato crop, Minnesota has changed the seed class designation on the Limited Generation System. These classes of certified seed potatoes in Minnesota are now designated by the true age of the seed. The first year of field production is now referred to as Generation 1 (G1), the second year of field production is now referred to as Generations 2 (G2) and so on down the line through Generations 6 (G6). So now, when you buy certified seed potatoes from Minnesota, you can be assured you are getting the true age of the seed. Please refer to the Limited Generation Chart in this directory.
Line Selections / Varietal Strains
The Minnesota Department of Agriculture Seed Potato Program certification confirms that each lot of potatoes in this directory have met the standards or requirements of State law, including but not limited to variety name and presence or absence of disease. This directory may also include line selection/varietal strains of certain identifiable varieties. This is indicated as “source documented as”. Although the certification tag may designate variety, strain or line selection names, that information is derived solely from the documentation supplied by the applicant for certification. Individual seed growers may have developed, or obtained from another source, lines/strains that possess yield, maturity, vine or tuber characteristics that may be different from the variety as originally described and named. A line/strain cannot usually be distinguished from the parent potato variety by conventional certification methods or by laboratory testing means. The seed grower is responsible for informing the seed buyer about line/strain existence and characteristics. Seed buyers should ask seed sellers about lines/strains that may be included among the seed lots listed.
MDA Contact
Nick Milanowski
Supervisor
651-201-6076
Potato Program
312 Fourth Avenue NE
East Grand Forks, MN 56721-2444
218-773-4956 | Fax 218-773-4959
Perry Paschke - Plant Industry Inspector II
Michael Bothum - Plant Industry Inspector II
Jim Horton - Plant Industry Inspector II
Eric Byre - Plant Industry Inspector II
Jeff Miller – Seed Potato Specialist
Jackie Anderson – Office & Administrative Specialist |