Principles of Plant Genetics and Breeding

Seed certification process
There are several key events in the seed certification
process that includes paperwork and fieldwork. The
specifics may vary among countries.
Application for certification
The developer (breeder, agency, company) wishing to
certify a new cultivar must first apply and receive approval
from the appropriate authority in the state. In the USA,
it is the responsibility of each state to establish the specific
protocol for producing each class of seed, as well as the
standards for genetic purity. These local standards, however,
should not be inferior to those set by AOSCA.
To apply for certification, the applicant is required to
supply information including the following: history or
origin of the cultivar, documentation of evaluations
conducted in comparison with other cultivars, a detailed
description of how the classes of seed (breeder, foundation,
registered, certified) will be maintained, the number
of generations that can be grown from the breeder
seed (or number of harvests from one generation in the
case of perennial crops), source of seed for planting, and
cropping history of the land.
Source of seed
The grower must use a seed class such as foundation or
registered seed of an approved cultivar for initiating the
certification process. The seed requirement is that the
starting seed must produce in the next generation a class
of seed that can be verified by a crop certificate (e.g.,
foundation seed to produce registered seed or registered
seed to produce certified seed).
Site selection (land)
A key requirement is that the land should not be a
source of contamination from volunteer plants or noxious
weeds. To this end, the land must not have grown
the crop in the recent (5 years) past (unless the previous
crop was the same cultivar and of a properly certified
class). Both primary and secondary noxious weeds
(especially those whose seeds are hard to separate from
the crop seeds) are intolerable. The site should be
adequately isolated to exclude contamination. This is
especially critical for open-pollinated species.
Management in the field
Once planted, the field must be kept free of weeds. Offtypes
must be rogued out, preferably before they flower.
SEED CERTIFICATION AND COMMERCIAL SEED MULTIPLICATION 445
Field inspection
While growing in the field, the crop is subject to
inspection by authorized personnel from seed certifying
agencies. The inspector looks for the presence of noxious
weeds, seed-borne diseases, and any factors that
might affect the purity of the cultivar.
Harvesting and processing
The equipment for harvesting must be thoroughly
cleaned to avoid mechanical mixtures from occurring.
The harvested seed is cleaned, conditioned, and bagged.
Representative samples are drawn from each lot by
officials from the seed certifying agency. Once determined
to meet or exceed the minimum standards set by
the association (e.g., Crop Improvement Association),
the seed is declared officially certified, and receives the
official tag. The tag indicates the results of seed analysis
(percent germination, inert matter, weed seed, etc.).
Seed testing
The information mandated on a seed tag that accompanies
a certified seed is obtained from laboratory evaluations,
collectively called seed testing. The Federal Seed
Act of 1939 mandated the use of seed tags or labeling.
Seed testing provides the information to meet legal standards,
determines seed quality, and establishes the rate
of sowing for a given stand of seedlings. The USDA is
the source of the procedures for seed testing in the US.
The Association of Official Seed Analysts also publishes
additional seed testing procedures for flowers,
trees, and shrub species. At the international level, the
International Seed Testing Association publishes
international rules for seed testing.
A seed testing lab conducts tests in five primary categories
– germination (viability), purity, vigor, seed health,
and noxious weed seed contamination. The first step in
seed testing is seed sampling. The rules of seed testing
provide guidelines for the proper sample size to be submitted
for seed testing pertaining to a particular species.
Seed testing or seed analysis consists of the following tests:
1 Seed germination test (viability). Seed viability is
determined by conducting the standard germination
test to determine the germination percentage (the
percent of normal seedlings produced by the pure
seed). The common methods of germination tests
are the rolled towel test (seeds rolled in moist paper
towel) or Petri dish test (seeds placed on absorbent