Effect of spraying time defoliator and speed of cotton harvesting machine on quality of cotton fiber

The development of mechanized harvesting as a way to reduce 30% the cost of production could raise the competitiveness of cotton production and maintain in the country. Using defoliator before machine harvesting is necessary to cleaning harvesting and high quality. To evaluate the effect of spraying time of defoliator and speed of cotton harvesting machine on machine performance and quality of cotton fiber, an experiment was carried out in Cotton Research Station of Hashemabad, Gorgan in 2014. The studied factors in this research were included two levels of spraying time of defoliator, two levels of cotton varieties suitable for mechanical harvesting and three levels of forward speed. The experimental design was split split plot in randomized complete block design with three replications and three factors. Results showed that harvesting time and speed did not affect the quality of the fiber. The effect of variety was significant on fiber quality, the importance of choosing the most suitable for mechanized harvesting of leads. Sepid variety in terms of quality index fibers had priority compared to the Golestan, and was suitable for machine harvesting.