The Development Characteristics And Regulation Of Boll And Fiber Quality For High-quality Cotton Cultivars

Three cultivars of high-quality cotton, Kemian No.1, Kemian No. 3 and Kemian No. 4, which were planted widely in the Southern cotton production area of China, were used to study the developmental characteristics and regulation of boll and fiber quality with the conventional fiber quality cultivar Sumian No.15 as the control. The objection of this study was to investigate the adjustable approach and physiological mechanism of improving fiber quality by regulating the boll development, and to provide the theoretical and practical foundation for both the formation of bigger boll and better fiber quality. The main results are as follows:1. The boll development characteristics were different between high-quality cotton and the conventional cotton. In comparison with the control (conventional fiber quality cultivar Sumian No.15), the boll length was longer, the boll volume was bigger and boll weight was higher for high quality cotton, but the boll diameter was similar with the conventional cotton. The boll length increased faster than that of the control within 10 days after anthesis (DAA) for the hybrid Kemian No.3, within both 10 days and 20-30 DAA for conventional cultivar kemian No.4. The boll diameter enhanced slower within 10 DAA, and the growth period was shorter for the high quality. The boll volume increased bigger within 20DAA, especially for 10 to 20 DAA for the high quality cotton. The boll weight bolstered higher within 10 DAA for hybrid Kemian No.3, and before 20DAA for conventional cultivar kemian No.4.2. The fiber development characteristics were different between high-quality cotton and the conventional cotton. In comparison with the control (conventional fiber quality cultivar Sumian No.15), The fiber length was longer, and increased faster after 20 DAA, the length was longer 10 mm than that of the control during 20 to 30 DAA, there was longer development period of fiber length for high quality cotton; The fiber maturity was higher, and increased fastest during 20 to 30 DAA for high quality cotton (during 30 to 40 DAA for the control); the fiber micronaire was lower for high quality cotton, and it increased before 40 DAA, maintained stable after 40 DAA, the fiber micronaire increased with boll development for conventional fiber quality Sumian No.15; the fiber strength was higher for the high quality cotton, and developmental period of the strength was during ripen, it was earlier for the high quality cotton. Genetically, there were significant positive correlation between the fiber length and the boll length, boll diameter, boll size and boll weight (r=0.9628**,0.9604**,0.9999**,0.9494**), negative...