Seed harvesting
- The basic rule of harvesting is to allow the seed to mature as long as possible on the plant without the seed or fruit becoming diseased, or overly ripe.
- It is important to harvest a seed crop at the time that will allow both maximum yield and the best quality seed.
The following points should be considered before harvest
– Seed is fully mature
– Weather damage has not started
– Seed can be easily harvested and cleaned
– There will be minimum harvest losses
Early Harvesting
- makes combine harvesting difficult
- relative losses due to threshing and cleaning are greater.
Late Harvesting
- increased weather damage to the seeds
- losses due to shattering of seeds
- lodging of plants in the field.
- Moisture content is a good indication of the optimum time of harvest in most of the seed crops.
- Combine harvester do not operate well above 15% seed moisture.
- For wheat, the optimum moisture content of 15-17% at the time of harvesting
- Maize ears are picked up even at as high as 30-35% moisture content.
Seed Threshing
- After harvest, seeds are threshed to remove the seed from the surrounding plant material.
- A period of air-drying is important before seeds are threshed.
- Plant material should be spread out in thin layers until all plant material is dry; otherwise, mold, decay, and heat from decay will cause damage to the seeds.
- As the plant material dries, seed pods may split open or shed seed.
- Plant material that is ready to be threshed should be brittle.