Effects Of Late Sowing And Topping Without Filming On Yield,Fiber Quality And Seed Quality Of Cropping Cotton

Sowing and topping are important for cotton production,quality and efficiency.In 2019 and 2020,Two factors of late sowing and late topping of cotton plants were set up,using Lumianyan28 as the test material in The Yellow River beach of Xinzhuang Village,Langcheng Gang Town,Zhongmou County,Zhengzhou City,Henan Province.The split plot experiment was used with late sowing as main plot andlate topping as the secondary plot,the experiment was repeated for 3 times.The late sowing without covering film treatment was 7,14 and21 days later than the normal sowing date（April 23）with covering film,respectively.And the late topping treatment was 7,14 and 21 days later,than the normal topping（July 20）,respectively.In order to clarify the effects of late sowing and late topping on cotton yield,fiber quality and cottonseed quality,we investigated and determined the part of the agronomic traits of cotton,cotton yield,fiber quality,cottonseed quality and different parts of the cotton plantunder different treatment.This study will provide scientific basis for green and efficient cultivation of simplified cotton.The main research results are as follows:1.From the point of view of cotton fertility process,the cotton fertility process of late sowing has a tendency to accelerate.Compared to normal sowing time,7,14 and21 days late,Five,ten and eight days later,The flowering stages were 3,7 and 9 days late,The flossing period was 3,7 and 10 days late,respectively.The delay of topping had no obvious effect on cotton fertility process.Compared with the normal sowing time and topping time（CK）,the plant height,fruit branch number and the first fruit branch position of cotton were significantly increased,and the dry matter accumulation of stem and bud bell was higher,but there was no significant difference between the dry matter accumulation in leaves and normal sowing time and topping treatment.However,7 days of late sowing had no significant effect on cotton plant height,number of fruit branches first fruit branch position and dry matter accumulation.2.Compared with the CK,the boll forming time of late sowing and late topping cotton was delayed and the space was moved up,and the boll forming number,seed cotton yield,lint yield and-frost flower rate all decreased to varying degrees.The results of two-year ANOVA showed that there was no significant difference in seed cotton yield and CK between 7 days of late sowing and 7 days of normal topping,7days of late sowing and 7 days of late topping,7 days of late sowing and 7 days of late sowing and 7 days of late topping.3.Compared with CK,the average length,fiber uniformity index,spinning uniformity index and yellowness of the upper half of cotton 1-4 fruit branches were not significantly different in the late sowing 7 days.But has a certain effect on fracture specific strength,macron value and reflectivity.Two years average,Treatment of 7days late sowing and 7 days late topping,14 days late sowing and 14 days late topping,21 days late sowing and 21 days late topping,The fiber fracture specific strength of 5-10 fruit branches was 1.33 cN tex^-1、0.16 cN tex^-1 and 1.90 cN tex^-1,respectively 1-4.The values of Macron were 0.63,1.03 and 0.26 lower than those of CK,fiber reflectance of 1-4 fruit branches decreased by 2.01%,2.16% and 3.58%compared with CK,respectively.4.Germination potential difference of cottonseed on 5-10 fruit branches was not significant compared with CK for 7 days late sowing and 14 days late sowing and 7days late sowing.After late sowing and late topping,the content of soluble protein and soluble sugar,germination potential and germination rate decreased,while the content of superoxide dismutase increased,and there was.5.Two years average,The benefit of 7 days of late sowing and 7 days of late topping increased by 154.86 yuan hm^-2,CK than that of the treatment.The economic benefits of 14 days of late sowing and 14 days of late topping,21 days of late sowing and 21 days of late topping were 2333.57 yuan and 3822.42 yuan hm^-2 less than that of CK sowing.To sum up,under the conditions of this experiment,compared with the normal sowing and topping of cotton,the treatment of 7 days late sowing,7 days late sowing and 7 days late sowing had no significant adverse effect on the main agronomic traits of cotton,and the difference of seed cotton yield,lint yield and pre-frost flower rate was not significant.The difference of fiber quality index and cotton seed quality was not significant.And 7 days of late sowing and 7 days of late topping reduce investment,benefit slightly increased,but also reduce plastic film pollution.Therefore,in production,it is suggested that the demonstration cotton should be planted 7 days late and delayed 7 days to hit the top,so as to realize the simplification and green cultivation of cotton.