Abstract:

To explore the changes of weight and quality of cotton bolls in the development process, cotton bolls of different stages were selected for analysis. The results show that: under the normal planting mode, the boll weight of upper (7th and above), middle (4th-6th) and lower (1st-3rd) fruiting branches are different, the boll weight in the middle part is the highest, followed by that in the lower part, and that in the upper part is the lowest, with the maximum difference of 1.6 g; during the development process of cotton boll, the weight of seed cotton, boll shell and lint cotton increase the fastest in 40-50 days after anthesis, and could reach the maximum in 70 days after anthesis, while the lint percentage could reach the maximum after 55 days of flowering. Among the fiber quality indexes, except that the short fiber content has a continuous decreasing trend, which is the greatest after 45 to 55 days of flowering, the other indexes present an overall increasing trend during the boll development process. However, the length, uniformity and elongation at break could reach the highest value at 65, 70 and 60 days after anthesis, respectively, with a decreasing trend. In conclusion, cotton bolls development process does not need to be as long as possible, 70 days after flowering, the boll weight, lint, length, strength, uniformity and other indexes will be reduced, which is not conducive to the improvement of cotton quality.

Key words: Xinjiang, Hami, cotton boll development, different stages, fiber quality