Sunday, March 29, 2015

Harvesting of paddy

Rice harvest was commonly practiced by hand-labor with sickle prior to 1970s. Rice threshing methods evolved from threshing panicles on a log threshing-stand into stripping on threshing hackle followed by employing tread-thresher in the 1940s.

Timing of harvest is crucial for grain quality and appropriate timing is often compromised because of competing activities or lack of labor for harvesting.

The introduction of combine thresher greatly improved the rice harvesting process including threshing. The combine harvester also improved soil fertility greatly as it simultaneously returned the chopped rice straw into the paddy soil.

Paddy is harvested at average moisture content between 16% and 28%, depending on the harvested method, the rice type and variety, the number of the cutting and the growth location. If left standing in the field, would incur heavy shattering losses that result in low production.

Most paddies deteriorate rapidly after harvesting and require immediate drying. Some new varieties should be dried immediately because they have a sh0rt dormancy period and will geminate within a few days after harvest.

In California, medium-grain rice is normally harvested at 20-26% moisture, second-cutting long-grain rice in Texas at 16-18%.

Drying method of harvested rice progressed from manual drying of un-threshed rice plants such as drying on paddy racks, standing small bundles and spreading on paddy field to the current machine drying methods.
Harvesting of paddy

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