中文摘要：

This experiments were conducted in Nanjing (118°50’, 32°02’) and Xuzhou (117°11’, 34°15’), Jiangsu Province, China, to study the response of fiber quality to the N concentration of the leaf subtending boll in cotton (Gossypium hirsutum L.). Results suggested that the N dilution curve of the leaf subtending boll can accurately indicate the stage-specific plant N status for fiber development. Fiber strength is likely to be the most variable fiber quality index responding to the leaf N variation which is different in cultivars. Fiber length was the most stable index among strength, length, micronaire, and elongation. There existed an optimum leaf N concentration for fiber strength development in each stage. The optimum leaf N regression curve was very close to the N dilution curve in the middle positional fruiting branches under the 240 kg N ha-1 soil N application rate.

英文摘要：

This experiments were conducted in Nanjing （118~50＂E, 32~02＂N） and Xuzhou （117~11 ＂E, 34~15＂N）, Jiangsu Province, China, to study the response of fiber quality to the N concentration of the leaf subtending boll in cotton （Gossypium hirsutum L.）. Results suggested that the N dilution curve of the leaf subtending boll can accurately indicate the stage- specific plant N status for fiber development. Fiber strength is likely to be the most variable fiber quality index responding to the leaf N variation which is different in cultivars. Fiber length was the most stable index among strength, length, micronaire, and elongation. There existed an optimum leaf N concentration for fiber strength development in each stage. The optimum leaf N regression curve was very close to the N dilution curve in the middle positional fruiting branches under the 240 kg N ha-1 soil N application rate.