Effects of Nighttime Temperature Increase at the Late Growth Stage on the Cotton Fiber Yield and Fiber Strength in Xinjiang

Abstract

Cotton yield and quality depend on genotype and environment interaction.Temperature is one of key factors to influ-ence fiber synthesis at the late growth stage of cotton.In the paper,Using early-maturing cotton varieties as experimental material,increased night temperature was simulated in the field using far-infrared quartz tube set mounted in semi-mobile incubators,rela-tive to normal night temperature treatment(control),to determine the effects of night temperature on the cotton yield and fiber strength at the late growth stage.The results showed that compared to the control,increased night temperature shortened cotton bolling period,the rapid accumulation at age of single boll fiber dry matter came earlier,and the single boll fiber yields signifi-cantly increased in the late growth stage of cotton.Increased night temperature mainly moved up the transformation from soluble sugar to fiber,and the duration was evidently extended,and also the initial time of rapid accumulation of cellulose synthesis came in advance,but the minimum night temperature ≥15.0℃ statistically had no effect on the duration of the rapid accumulation and the maximum accumulation rate before end of cellulose speedy accumulation period.Simultaneously,the fiber strength was af-fected slightly by minimum night temperature ≥14.1℃ during in the cotton fiber development.So the minimum temperature in the nighttime was a major factor associated with soluble sugar transformation and cellulose accumulation.Consequently,dry mat-ter accumulation and fiber yield of single boll were closely associated with the minimum nighttime temperature.