Thousand grain mass
The thousand grain mass (TKM) (or outdated: thousand grain weight (TKG)) is the mass of 1000 grains . The thousand-grain mass is a parameter in seeds , in the seed trade , in plant breeding , in the storage of seeds in crops and in grain mills .
application
In the seed industry
The international rules for seed testing are published by the International Seed Testing Association .
In the seed libraries you can find information on the TKM of
- Industrial plants for technical use such as dye plants
- Food crops , e.g. B. Grain ,
- Useful plants as renewable raw materials such as oil plants ,
- Pharmaceutical plants , e.g. B. St. John's wort and
- Wild plants from biotopes .
In the milling
To determine the thousand grain mass of a batch of grains, random samples are taken and counting devices are used. Grains can be stored with a water content of less than 14%. If grains with a higher moisture content are harvested, special grain drying processes are used, with the drying temperature playing a special role in order not to impair the germination of the grains.
The TKM is a varietal characteristic that is subject to strong fluctuations due to the respective cultivation and weather conditions in the year of production. The higher the TKM, the better the ratio of grain mass and shell proportions - with a higher TKM of grain, the miller can achieve a higher flour yield .
Average thousand grain mass
1000 storable grains weigh in:
| Tobacco : | 0.1 g |
| Teff : | 0.3-0.5 g |
| Amaranth : | 0.5-2 g |
| Clover : | 1-2 g |
| Quinoa : | 1-3 g |
| tomato | 2-3 g |
| Grass : | 2-5 g |
| Rapeseed : | 2-7 g |
| Buckwheat : | 15-30 g |
| Rice : | 15-45 g |
| Oats : | 27-48 g |
| Rye : | 28-50 g |
| Barley : | 35-50 g |
| Triticale : | 40-58 g |
| Wheat : | 40-65 g |
| Corn : | 200-450 g |
| Peas : | 150-500 g |
| Beans : | 150-550 g |
| Sycamore maple : | 800 g |
Calculation of the sowing rate based on the thousand grain mass
The TKM is also required to calculate the amount of seeds to be sown .
Example of sowing winter wheat:
- Target number of plants per m² = 300
- TKM = thousand grain mass in grams = 60
- M = reduced germination capacity in percent = 6
- Seed rate (required amount of seed) ≈ 191 kg / ha
Calculation of the sowing rate taking into account the estimated field emergence loss and the expected number of ears per seed:
Calculation example for sowing winter wheat:
- Target number of plants per m² = 580
- Convenience coefficient = 2.2
- TKM = thousand grain mass in grams = 60
- M = reduced germination capacity in percent = 6
- F = field opening losses in percent = 5
- U = winter losses in percent = 3
See also
Individual evidence
- ↑ Determination of the moisture content of seeds according to LTZ Augustenberg
- ^ Burghard Kirsch: Milling technology, materials science. Composition, study, evaluation and use of grain and grain products . 8th edition. Bayerischer Müllerbund, Munich 2016, ISBN 978-3-9812436-6-6 .
- ↑ a b c Thomas Miedaner, Friedrich Longin: Underestimated Streidearten - Einkorn, Emmer, Dinkel & Co. Agrimedia, 2012, ISBN 978-3-86263-079-0 .
- ↑ Andreas Roloff : Trees of Central Europe: From Aspe to Swiss stone pine. 1st edition. WILEY-VCH Verlag, 2010, ISBN 978-3-527-32825-3 .
- ↑ Seed times and seed strengths (advice from the Chamber of Agriculture North Rhine-Westphalia) (PDF; 85 kB).
Remarks
- ↑ Desired number of plants per m² = target stand density: How many spiked stalks per m² are typical for the site and should therefore be aimed for when harvesting a high yield?
- ↑ Approximation coefficient = How many spiked stalks per overwintered seedling are available on average for harvest?
- ↑ ( M + F + U ) = (reduced germination capacity + field emergence losses + overwintering loss)