Agriculture Reference
In-Depth Information
tions) from the submitted sample should be done quickly to avoid exposing the seeds to the ambient air for
more than one minute. The size of each sub-sample is indicated in Table 11.1
Sample Preparation
Grinding and cutting:
Table 11.1 lists species for which grinding or cutting is recommended. Grinding
and cutting is usually necessary for large seeds to ensure uniform drying, or for seeds that have physical
barriers. Grinding for seeds of high oil content is not recommended. Grinding and cutting should be done
before drawing the two replications needed for moisture determination.
Pre-drying:
Pre-drying is necessary for species that require grinding but have moisture contents above
17%. This is achieved by placing seeds overnight in thin layers is an air-oven set at a constant 70°C. Seeds
are then weighed and their moisture content determined.
Oven drying:
The duration and temperature at which each species should be dried are listed in Table
11.1. After the prescribed drying time, samples are removed from the oven, covered immediately and cooled
in a desiccator for approximately 45 minutes and their dry weight determined.
Table 11.1. Air-oven methods for seed moisture testing reported to give results in agreement with
basic reference methods.
Drying
period
Sample
prep
Sample
size (g)
Temp
°C
Reference
method
Species
Common name
H
M
Field crop seeds
Agrostis capillaris
L
.
Colonial bentgrass
Whole
10
130
1
0
Karl Fischer
Avena sativa
L.
Oat
Whole
10
130
23 0
Karl Fischer
Avena sativa
L.
Oat
Ground
5
130
2
0
Karl Fischer
Bothriochloa ischaemum
(L.)
Keng
Yellow bluestem
Whole
1
100
1
0
Karl Fischer
Brassica napus
L. var.
annus
Koch
Annual rape
Whole
10
130
4
0
Karl Fischer
Bromus inermis
Leyse. subsp.
inermis
Smooth brome
Whole
5
130
0
50 Karl Fischer
Carthamus tinctorius
L.
Saflower
Whole
10
130
3
0
Karl Fischer
Dactylis glomerata
L.
Orchardgrass
Whole
3
130
1
30 Karl Fischer
Festuca arundinacea
Schreb.
Tall fescue
Whole
3
130
3
0
Karl Fischer
Festuca rubra
L. subsp
. rubra
Red fescue
Whole
3
130
3
0
Karl Fischer
Glycine max
(L.) Merr.
Soybean
Ground
2-3
130
1
0
Vacuum-100°C
Helianthus annus
L.
Sunlower
Whole
10
130
1
0
Karl Fischer
Hordeum vulgare
L.
Barley
Whole
10
130
20 0
Karl Fischer
Hordeum vulgare
L.
Barley
Ground
5
130
2
0
Vacuum-P
2
O
5
Kummerowia stipulacea
Maxim
Korean lespedeza
Whole
12
100
2
0
Karl Fischer
Lens culinaris
Medic. subsp
.
culinaris
Lentil
Ground
2-3
130
1
0
Vacuum-100°C
Linum usitatissimum
L.
Flax
Whole
10
103
4
0
Karl Fischer
Lolium perenne
L.
Perennial ryegrass
Whole
5
130
3
0
Karl Fischer
