| Cotton bolls are the foundation of yield and quality.The growth and development of cotton bolls have a great impact on the formation of yield and fiber quality.The increase in cotton yield will inevitably involve the single boll weight of its constituent elements.Previous studies on cotton boll material accumulation and physiological and biochemical comparisons Many,but combined with electron microscopy to observe fiber morphology changes less.This paper mainly compares the differences in cotton boll development and yield-related traits of the main upland cotton varieties cultivated in Alar reclamation area,and uses two chemical topping formulas to treat two of these varieties to determine the material accumulation,photosynthesis,canopy structure,The law of bell formation,the economic traits of single bell and the difference of fiber development morphology,etc.,mainly have the following conclusions:1 Development characteristics of upland cotton bolls(1)The dry matter accumulation of cotton bolls showed that the dry weight of cotton bolls was15-1242>Xinluzhong 70>Xinluzhong 82,the flowering period of No.14>the flowering period of No.7>the flowering period of No.21.The proportion of boll shells in the dynamic distribution of 70 cotton boll material accumulation in Xinlu decreased the fastest,from 65% to 19%,and the fiber rate and seed rate increased the fastest,from 15% to 37% and 18% to 42%,respectively.(2)Scanning electron microscopy observation of fiber development shows that the number of ovule epidermal cells and the number of fiber elongation showed the largest flowering period on the 14 th and the smallest flowering period on the 21st;Xinluzhong 82 at the same flowering stage was more than Xinluzhong 70 and 15-1242 entered the thickening phase of the fiber earlier.At the same time of fiber development,the 14 th flowering period entered the thickening period earlier than the 7th and 21 st flowering periods.(3)Yield and yield traits can be seen that 15-1242 has a smaller clothing size,economic coefficient,number of bolls per plant and yield per plant than Xinluzhong 70 and Xinluzhong 82.The boll weight is larger,the bolliness is strong,the yield per plant is high,and the advantage per plant is obviously stronger than that of Xinluzhong 82 and 15-1242.2 Research on the regulation effect of chemical topping on cotton boll development(1)The characteristic time of boll dry weight,single fiber weight,single seed cotton weight and volume growth performance is that Xinluzhong 82 is earlier than Xinluzhong 70,and the chemical boring material accumulation of cotton bolls is slower than artificial topping in the early stage.Later period is faster than manual topping.(2)The lower leaf area index of chemical topping increased slightly,which increased the effective photosynthetic area;the upper and middle canopy openings both showed an increase,and the lower canopy opening did not change much.The overall canopy opening of Luzhong 70 is more loose,and the canopy structure is more reasonable,which is conducive to the increase of light in the lower part.The net photosynthetic rate of chemical topping treatment was significantly different from that of artificial toppingwithin 30 days after treatment.The intracellular carbon dioxide concentration,stomatal conductance and transpiration rate were higher than that of artificial topping,and there was no significant difference;the upper and middle SPAD values were respectively after treatment The 30-day and 20-day chemical topping treatments are larger than manual topping,and the lower chemical topping of Xinluzhong 82 is lower than manual topping.(3)The chemical topping formula 1(Cashin)promotes the boll formation rate of autumn peach.The economic traits of cotton bolls in the three flowering stages of Xinluzhong 70 all show that chemical topping is stronger than artificial topping.Topping formula two(Wanjiafeng)is better than chemical topping formula one;chemical topping can improve the economic characteristics of single bell of Xinluzhong 82,but formula one treatment reduces the economic characteristics of upper single bell.Under the formula two treatment,the single bell weight and the number of single plant bells increased the most,and the yield per plant was also the highest.The single bell weight of the formula one increased and the single plant bell number decreased.Formulation 1 treatment can increase the fiber strength of the middle and upper parts of Xinluzhong 70 and the average length of the upper half of Xinluzhong 82.(4)Scanning electron microscopy observations at 14 d and 21 d for the development of the upper fibers showed that chemical topping significantly delayed the fiber development of Xinluzhong 82,and the chemical topping formula one at 21 d compared to the formula two The delayed effect on fiber development is stronger.At the same time,chemical topping can also delay the fiber development of Xinluzhong 70 at 21 days. |
PDF Full Text Request