Potato Science Lecture 9
Seed certification principles, agencies,
and regulations.
Potato Science Lecture 7
Seed certification principles, agencies,
and regulations.
Seed Certification
 Purpose and principles
Agencies
Regulations
History of Certification
1900 - Dutch and Germans recognized
chronic diseases and initiated roguing
.
1912 - U.S. Quarantine Act passed
1913 to 1922 - Certification agencies
organized in 22 states
Purpose of Certification
“…to maintain and make available to the
public high quality seeds of superior crop
varieties so grown and distributed as to
preserve genetic identity and purity.”
ICIA Rules of Certification
NOTE!
“Certification” is NOT a guarantee that
no problems will occur. It indicates that
the crop has met the rules of the
certification agency.
XII. Disclaimer Representation and Limitation of Remedy and
Liability
A. Since the use of certified seed potatoes is beyond the control of
the grower, the seller, the inspector, the Idaho Federal-State
Inspection Service and the Idaho Crop Improvement Association,
Inc. Make NO representation of any kind, expressed or implied,
including merchantability, fitness for a particular purpose,
quality or freedom from disease, is made concerning certified
seed potatoes which extends beyond the description set forth.
Certified Seed Potatoes
Not a Guarantee, but…
 Produced under strict guidelines
 Many inspections
 Not commercial production
 Seed is more expensive to produce
 Seed is more risky
“Limited Generation”
 Lab derived, disease-free stocks
 Increased a “limited” # of years
 G6 last generation allowed (ID)
 Most is G3 with G2 < and G4>
Inspections
 2 summer field inspections
Storage inspections
 Winter grow-out in CA
 Shipping point inspections
Why Inspect ?
 Disease (virus, BRR, others)
 Variety mixes
 Herbicide damage/carryover
 Seed lot identity
 Other?
The Idaho Crop Improvement Association, Inc. inspector and Idaho
Federal-State inspector are given authority to refuse to tag and seal
any seed potatoes for any condition or situation that may bring
certification into disfavor or make an accurate inspection
impossible.
IDAHO CROP IMPROVEMENT ASSOCIATION, INC.
RULES OF CERTIFICATION
for
SEED POTATOES IN IDAHO
PART I - GENERAL INFORMATION
http://www.idahocrop.com/StandardDocs/97Potato-R&R07.pdf
Certification Procedures
Considered to be a voluntary program
(majority consent)
Each state agency published regulations
approved by grower advisory committees
Certification is issued for potato lots that
meet regulations
Certification Procedures
Certification based on a series of inspections
Certification can be withheld only upon
failure to meet regulations
Most states now use a limited generation
program
Certification Agencies
State agencies are independent
May be sponsored by grower groups,
agriculture departments, universities, or
other organizations
Regulations, terminology, and
tolerances differ by state
Certification Terms
Certification - attaching of the official
certification tag
Certified seed - potatoes that have met
Idaho Rules of Certification and met
grade requirements
Generation - a classification scheme
based on years of field production
Certification Terms
Limited-generation seed - seed
originating from a pathogen free source
and grown for a maximum number of
years (7) in the field
Seed lot - seed potatoes from a field(s)
entered for certification on a single
application
Certification Terms
Disqualification - removal of eligibility for
certification status
Downgrading - changing generation status
due to failure to meet tolerances
Recertifying – registering and growing for
another season in the seed program
Roguing - removal or destruction of
diseased or undesirable plants from a lot
Certification Terms
Tolerance - maximum amount of a
certification factor allowed
Zero tolerance factor - none of the
factor allowed in a seed lot (ring rot, RK
nematode, CRS)
Shipping point inspection - inspection of
tubers after grading but prior to
shipping
Tolerances have been established for :
Potato Virus Y
Potato Leaf Roll
“PLRV”
Potato Leaf Roll
“Net necrosis”
PVY
Tuber necrotic ringspot
“PTNRD”
Zero tolerance disease :
Bacterial Ring Rot
“BRR”
Variable? tolerance disease :
Bacterial Soft Rot/
Blackleg
Disease of note:
Potato late blight
Certification Procedures
Identity preserved lot entered by grower
Five inspections conducted
Two summer field inspections
storage inspection
winter test inspection
shipping point inspection
Certification tag attached
Certification Procedures
Eligibility
Seed farm eligibility
 all seed entered
Seed stock eligibility
 limited generation clause
 previous certification
 no BRR on production farm
 out-of-state seed meet state tolerances
Certification Procedures
First Field Inspection
Land Requirements
 No RK nematode, CRS, Rhizomania
 No uncert potatoes or BRR year before
Isolation Requirements
 20 feet from uncertified
 6 feet from other certified
Certification Procedures
First Field Inspection
Meet field tolerances for
Varietal mix
PVY and mosaic
Leafroll
Blackleg
Total virus
Samples taken for PVX tests
Certification Procedures
Second Field Inspection
Meet field tolerances for
Varietal mix
PVY and mosaic
Leafroll
Blackleg
Total virus
Certification Procedures
Storage Inspection
Eligibility maintenance
Absence of sprout inhibitors
Absence of other problem potatoes
Lot identity maintained
Lot separation
Certification Procedures
Winter Test Inspection
California Winter Test
ELISA testing
Seed Seminar Program Report:
2013 Winter Test Update
21 January, 2014
Certification Procedures
Shipping Point Inspection
Grade tolerances for rot, size, freezing
injury, scab, defects, mechanical
injury, varietal purity, and foreign
material
Blue Tag - 10% defects, 3% freezing
injury, 1% rot
Also Green Tag, Yellow Tag
XI. Grade Requirements
A. Idaho Certified Blue Tag Seed Potatoes
The blue tag shall be equivalent to U.S. No. 1 seed potato grade with
the following exceptions. There is a 1% tolerance for late blight.
1. Scab - shall not cover more than one-fifth of the surface area.
2. Adhering dirt - a maximum of 50% of the tuber surface may be
covered with caked dirt.
3. Loose dirt and/or foreign material - included in total external
tolerance.
4. Clipping or trimming not allowed.
5. Freshly broken off second growth - shall not be damaged.
6. Wireworm - damaged by waste.
7. Tolerances: For total defects 10%. Three percent (3%) for potatoes
The blue tag shall be equivalent to U.S. No. 1 seed potato grade with
the following exceptions.
B. Idaho Certified Green Tag Seed Potatoes
The green tag grade shall be equivalent to the U.S. No. 2 grade with
the following exceptions. There is a 1% tolerance for late blight.
1. Size - 1 3/8 inches minimum
C. Idaho Certified Yellow Tag Seed Potatoes
The yellow tag grade shall be equivalent to the U.S. No. 2 grade with
the following exceptions. There is a 1% tolerance for late blight.
1. Size - 12 ounces maximum - no minimum size, unless otherwise
specified.
Theory
Practice
Seed Certification is:
A system that provides quality seed
 That will perform for the producer
 Minimal risk – but nothing’s perfect
 Achievable by seed producers
 Process is dynamic
 Rules can be changed
Seed Certification Costs
Quality seed isn’t cheap!
 Currently costs 25.40 / acre
 Locked in for a few years
 Will need to be increased?
 When?
 How much more?
Case History
PVY in Idaho 1990-2011
PVY vs Certification in Idaho
Solution arrived at by trial and error
 Recertification tolerances very low %
 Commercial seed = higher tolerances
 1990 >5% PVY = rejection
 1997 >10% = rejection
 2000 >15% = rejection
 2005 no rejection for virus
Certification Procedures
Winter Test Inspection
California Winter Test
ELISA testing
Cert. Recert.
Leafroll
2% 0.8%
PVY
10% 2.0%
?
Rationale
Why eliminate tolerances on cert seed?
 Achievable by seed producers?
 Out-of-state seed meets ID tolerances?
 States don’t control each others rules
 This change leveled the playing field
PVY vs Certification in Idaho
The train wreck of 2007
 2007 frost at winter test site
 Several lots certified with >50% PVY!
 Lots of negative fallout
 ICIA abandoned visual insp for PVY
 100% of the crop is now ELISA tested
Has this change been effective?
PVY in Idaho seed 2007-2013
100
80
27
20
51
60
19
12
19
2007
2008
34
2009
Clean
13
21
37
25
50
54
2012
2013
50
61
20
0
8
40
60
40
16
52
31
2010
Infected
2011
Ineligible
Current and Future
Issues
Idaho Certified Seed Law
Non-certified seed can be used if:
Only one year out of certification
 User must have grown crop himself
User must have stored crop himself
Must be winter tested for PLRV, PVY
and BRR.
Canada/US-Management Plan for Potato
Viruses that Cause Tuber Necrosis
This plan proposes immediate measures to manage the
risks associated with several pests that occur in both
countries, including Potato mop top virus (PMTV), Potato
virus Y (PVY) complex and Tobacco rattle virus (TRV),
through seed potato certification measures. Through
surveys and research, data will be collected and evaluated
to better understand the biology of these viruses and their
vectors, thus enabling the establishment of further control
measures.
Certification Agencies
State agencies are independent
Rules different state to state
Other countries = one unified system
 USA system confusing for them
 Causes problems with exports
 MOU?