Grain Guide 2016

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26 GRAANGIDS 2016 GRAIN GUIDE
Droëland:
Besproeiing:
2. Maize
2.1 A guideline of 0,28 g/kernel can be used for the average kernel mass of maize where the
seeds can be counted in order to calculate the potential crop.
2.2 When the seeds cannot be counted, 120 g to 180 g per ear, depending on the establishment
and occurrence of multiple ears, can be used.
2.3 First determine the average number of ears per 10 m. When the plants are in the vegetative
stage, factors like the establishment, multiple ears and the sprouting ability of the plants must
be taken into account.
2.4 Determine the average mass in grams per ear.
2.5 The formula below can now be used to calculate the yield.
3. Sunflowers
3.1 Use the following guidelines to determine the average seed mass per head at a young stage
before the seeds on the head can be counted:
3.2 Use the following method to count the seeds per head:
3.2.1 Measure the diameter of the head.
3.2.2 Measure the diameter of the centre seed set if applicable.
3.2.3 Count the number of seeds per 10 cm2 and divide this number by 10 to obtain the number
of seeds per cm 2.
3.2.4 Calculate the productive area as follows:
Diameter of head = 15 cm
Diameter of centre seed set = 5 cm
Total area = 15 x 15 x 0,79 = 177,75 cm2
Unproductive area = 5 x 5 x 0,79 = 19,75 cm2
Productive area = 177,75 cm2 - 9,75 cm2 = 158,00 cm2
Ears or stalks per 3 m x seeds per ear
Row width (m) x 3 x 3 500
= t/ha
Ears or stalks per 3 m x seeds per ear
Row width (m) x 3 x 3 000
= t/ha
E-pos:
Tel: (051) 407-3123
Sel: 082 574 5355
Number of ears per 10 m
1 000
Grams per ear
Row width
x
50 000
40 000
30 000
20 000
10 000
34
41
48
55
62
ESTABLISHMENT/PLANTS/HA GRAMS SEED/HEAD
1.2.2 The number of ears or stalks in the row over a distance of 3 m is counted.
1.2.3 The number of seeds per ear is determined by counting a sample of ears, which includes
small and large ears in proportion. If the seeds cannot yet be counted, a good average count
for the cultivar concerned can be used.
1.2.4 The formula below can be used to calculate the yield where wheat has been planted in
distinguishable rows.
Do your own crop estimate
Continued from the back of the Seed tab
Continued on p. 30