the existing studies of threshing process of combine harvesters adopt the assumption of constant mass, which is contradictory to the phenomenon of separation of grains and short stalks in actual threshing process. therefore, the characteristics of threshing and separation are not accurately described. aiming at this problem, this study established the tangential-longitudinal threshing and separ...

Significant increases in rice production can be obtained in sub-Saharan Africa (SSA) by increasing rice grain yield in existing production systems, expanding rice harvested area, and reducing harvest and postharvest losses. However, availability of labour at critical times is often a major constraint, and this situation is aggravated by the effects of the HIV/AIDS pandemic. Delays during harves...

There are various designs of tools and equipment used for harvesting the crops and threshing it separately. Sickles, hand tools and reapers for grain crops and diggers for tuber crops and rhizomes, operated with different power sources are used. Combine harvesters, both tractor mounted and self-propelled, are being very widely used for different grain crops. Functional requirements and principl...

It is widely believed that hexaploid wheat originated via hybridization of hulled tetraploid emmer with Aegilops tauschii (genomes DD) and that the nascent hexaploid was spelt, from which free-threshing wheat evolved by mutations. To reassess the role of spelt in the evolution of Triticum aestivum, 4 disomic substitution lines of Ae. tauschii chromosome 2D in Chinese Spring wheat were developed...

cumin is an annual plant suitable for dry and semi-dry regions. it is harvested at two stages to prevent seed shedding. first, the cumin bushes are harvested by hand or using a scythe. after drying, the cumin bushes are beaten with a stick or trampled using animals or a small tractor. this harvesting method is time consuming, requires intensive labor and is an incomplete threshing process resul...

Wheat domestication from wild species involved mutations in the Q gene. The q allele (wild wheats) is associated with elongated spikes and hulled grains, whereas the mutant Q allele (domesticated wheats) confers subcompact spikes and free-threshing grains. Previous studies showed that Q encodes an AP2-like transcription factor, but the causal polymorphism of the domestication traits remained un...

Some mechanical and process parameters of a developed millet thresher have been optimized using numerical optimization technique. The machine threshes panicles cleans the grains from straw. speed threshing number pegs attached to drum were investigated, while moisture content was parameter under investigation. Threshing efficiency, cleaning percentage losses used as performance characteristics ...

Combine harvesters are widely used worldwide in harvesting many crops, and they have functions that cover the entire process, such as cutting, threshing, separating, cleaning. The threshing drum is core working device of combine harvester plays an influential role rice efficiency, power requirement, seed loss. In this study, two structures threshers (conical-shaped cylindrical-shaped) were test...