新疆产棉区高强棉纤维形成的纤维素累积特征及适宜温度

Cellulose Deposition Characteristics of High Strength Cotton Fiber and Optimal Temperature Requirements in Xinjiang Region

【目的】新疆是我国主要产棉区,该区棉花生育后期气温下降快。明确生育后期温度对棉纤维发育的影响,对新疆优质棉生产提供指导。【方法】采用分期播种、整段夜间增温(棉纤维发育期)和阶段夜间增温(开花至纤维素快速累积期起始时间、纤维素快速累积期和纤维素快速累积期终止时间至吐絮)的方式,使棉纤维发育处于不同的温度环境下,研究温度对纤维素累积特征的影响及其相互关系。【结果】结果表明,棉纤维比强度受纤维素快速累积期持续时间(T)、开花至纤维素快速累积期起始时间的平均累积速率(V1)和纤维素最大理论含量(Wm)的显著影响,其中棉纤维比强度与V1呈显著二次曲线关系、与Wm呈极显著线性关系。棉纤维发育期≥15℃有效积温是影响纤维比强度的主要温度因子,在开花至纤维素快速累积期起始时间内二者呈显著负相关关系,在纤维素快速累积期则呈显著正相关关系。自棉花开花至纤维素快速累积期起始时间内,较多的有效积温使纤维素在这段时间的平均累积速率(V1)直线降低,这并不利于纤维比强度的提高。在纤维素快速累积期,≥15℃有效积温的增加显著提高了V1,纤维素快速累积期持续时间(T)随有效积温的增加而显著延长,纤维比强度亦呈增加趋势。若获取≥30 cN/tex的纤维比强度,就需要V1维持在1.32%·d-1—1.76%·d-1,纤维素在铃龄6.7—13.3 d进入快速累积期,快速累积期持续20.2—25.6 d,纤维素累积时间经历39.0—46.9 d;在开花至纤维素快速累积期起始时间内需要≥15℃有效积温5.6℃—96.3℃,在纤维素快速累积期则需要181.5℃—262.3℃。【结论】棉纤维不同发育阶段≥15℃有效积温对V1影响的差异性是造成纤维比强度差异的主要原因,适宜V1有利于形成高强纤维。

【Objective】 Xinjiang region is a major cotton growing-region in northwest China. Temperatures in the region, especially night-time temperatures, drop drastically at the end of the cotton growing season. The objective of research was to explicate the effects of temperatures on fiber development, so as to benefit to cotton production. 【Method】 Three field experiments were conducted by different sowing dates, elevated night-time temperature during entire fiber development（from anthesis to boll opening） and elevated night-time temperature during different stage of fiber development（from anthesis to the onset of rapid cellulose deposition, between the onset and termination of rapid cellulose deposition, and from the termination of rapid cellulose deposition to boll opening）. The effects of temperatures on cellulose deposition were analyzed to explore the temperature conditions for producing high fiber strength. 【Result】 Fiber strength was significantly affected by the duration of rapid cellulose deposition（T）, the average rate of cellulose deposition from anthesis until the onset of rapid cellulose deposition（V1） and the maximum cellulose content（Wm）. Fiber strength was quadratically related to the V1 and was positively correlated with the Wm. Growing degree days was the factor associated with cellulose deposition in cotton fiber. The relationship between both was going to go the other way during the different fiber developing stages. During the early stage of fiber development（anthesis to the onset of rapid cellulose deposition）, growing degree days was significantly and negatively correlated with fiber strength, whereas there was positive relationship between both during the period between the onset and termination of rapid cellulose deposition. During the period from anthesis until the onset of rapid cellulose deposition, the average rate of cellulose deposition decreased as growing degree days increased, which had an unfavorable about fiber strength. During the period of rapid cellulose deposition, growing degree days increased significantly the cellulose deposition rate during from anthesis until the onset of rapid cellulose deposition and the duration time of rapid cellulose deposition, then fiber strength increased. There was a possibility of producing more than 30 cN/tex of fiber strength, when the following conditions were met：（1） the V1 was between 1.32%·d-1 and1.76%·d-1;（2） cellulose deposition entered the onset of rapid cellulose deposition（t1） at 6.7-13.3 days post-anthesis（dpa）;（3） the duration of rapid cellulose deposition（T） was 20.2-25.6 days;（4） the time of cellulose deposition was 39.0-46.9 days, and（5） the growing degree days was 5.6℃-96.3℃ and 181.5℃-262.3℃ during from anthesis until the onset of rapid cellulose deposition and the duration time of rapid cellulose deposition, respectively. 【Conclusion】 Therefore, growing degree days resulted in different effects on fiber strength during the different fiber developing, and the main reason was that growing degree days caused variability effects on the average cellulose rate during the period from anthesis until the onset of rapid cellulose deposition.