| Regulation of agricultural and horticultural
seed: This page is a direct copy from The Official Seed Testing Station.
Division: The Official Seed Testing Station
Organisation: Department of Agriculture and Food
Address: Abbotstown Laboratory Complex, Snugborough Road, Dublin 15. .
Telephone: (01) 6072575.
Department of Agriculture and Food.
(Text copied from DAF)
All the important agricultural and
horticultural seeds are now subject to official certification
and control requiring official testing for germination and
This is the responsibility of the
Official Seed Testing
Station (O.S.T.S.) of the Department of Agriculture and Food.
Consequently the majority of tests are now carried out for
official seed certification purposes while in the past they were
mainly done for the seed merchants and farmers as an advisory
service. This section outlines the range of tests available for
the OSTS that may be relevant to you
The germination test determines the actual germination
potential of normal seeds within a seed lot which can be used to
compare the quality of different lots and also estimate the
field planting value.
The accurate assessment of germination potential is carried
out by competent seed analysts using specialised germinators and
growth substrates. The aim is to determine the optimum
germination capabilities of the seed under ideal conditions. The
Station analysts are trained to recognise the major causes of
poor seed germination, primarily abnormalities caused by disease
or resulting from drying, mechanical, sprouting or dressing
Germination tests take varying lengths of time to complete;
for example cereals take 12 to 14 days, while some grasses
require 21 days and certain wildflower and tree species up to 6
The germinators used are designed so that the requisite
amounts of heat, air, moisture and light specified by the ISTA
Rules can be accurately controlled. If dormancy is involved the
seed may be pre-chilled, pre-heated or treated with either
giberellic acid or potassium nitrate before the actual
germination test commences. The dormancy breaking treatment used
depends on the species to be tested.
This determines the percentage weight of seeds in the sample
under examination which is true to type and is genuine seed of
the kind named. It does not confirm varietal purity, which can
be only be obtained by growing the seed to maturity.
To determine purity the analyst examines the sample seed by
seed, under magnification where necessary. All normal seeds of
the desired species are segregated from the various impurities,
and weighed to determine the percentage purity of the seed
Impurities in a sample usually consist of
- Weed seeds
- Other crop seeds,
- Inert matter, (e.g. broken grain, soil, scraps).
In the case of grasses, ‘seeds’ which are true to name
but which contain no kernel (caryopsis), or contain only an
undeveloped kernel, are regarded as inert matter and therefore
classed as impurities. The components of the various impurities
are identified in the final report produced by the Station. The
significance of harmful impurities, such as noxious weeds,
should not be overlooked.
While information on the percentage germination is essential
for good establishment of seeds, many growers also require
information on the Thousand Seed Weight of the seed lot when
planning seedling population.
The Thousand Seed Weight test based on ISTA Rules will be
available, upon request, from January 2000.
The official method for testing moisture content is by oven
drying and temperatures and over periods of time specified
according to the I.S.T.A. Rules. The moisture content is
represented as a percentage of the sample weight.
The moisture content of seed can affect storage life and can
also affect germination after chemical treatment.
Instantaneous moisture metres are generally accurate and are
commonly used by seed merchants and growers. It is essential
that they are checked regularly to ensure accuracy. The O.S.T.S.
can, on request, conduct moisture tests on all kinds of seed.
These results can be used to check the calibration of moisture
Samples for moisture tests should be submitted in a strong
plastic bag from which all the air has been removed and then
Other Seed Testing Services
The O.S.T.S. also provides a range of tests in addition to
the above, including tests on the seeds of grass and clover,
peas and beans, linseed, vegetables, trees and wildflowers.
Technical index: The
following link is a real time alphabetical list of technical pages in this
By Category - Technical Pages
Go on choose Design
By Nature for seeds, plants, advice and design.
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Return to Folder/Section: Index - Technical Section. includes the Conservation section, Mulching and advice on certain weeds, phytosanitary.