两个不同彩色棉纤维品质性状形成特点及生长调节剂调节作用

选择天然棕色棉品种湘彩棉2号和绿色棉品种皖棉39，研究其纤维品质性状形成特点及激素调节作用。结果表明与常规白色陆地棉苏棉9号(对照)相比，2个彩色棉品种的纤维长度均较低，尤其皖棉39显著低于对照，主要是花后10~30 d伸长速率明显下降。两个不同彩色棉品种的纤维比强度、马克隆值和成熟度值均显著低于对照，且主要与各个品质指标形成关键期的增长率较慢有关。两个彩色棉品种10 DPA (days post anthesis)和20 DPA纤维中IAA含量，30 DPA和40 DPA ABA含量均显著低于各自对照。应用20 mg L^-1 GA₃处理棉铃后，湘彩棉2号、皖棉39 20 DPA纤维中IAA含量分别比各自对照提高51.07%、64.33%；吐絮时纤维长度分别比各自对照增加8.13%、13.96%；应用20 mg L^-1 ABA处理棉铃，40 DPA纤维中ABA含量分别比各自对照提高38.96%、24.40%，纤维比强度、马克隆值和成熟度也显著增加，其中又以皖棉39增加幅度较大。说明天然彩色棉纤维内源激素IAA和ABA含量不足影响纤维品质性状的形成，而通过植物生长调节剂应用可调节内源激素含量，改善纤维品质，且调节效应因植物生长调节剂和品种不同而异。

Characteristics of Fiber Quality in Cotton Development and Its Regulation by Hormone in Two Natural Colored-Cotton Cultivars

The brown cotton cultivar Xiangcaimian 2, green cotton cultivar Wanmian 39, and white fiber control cultivar Sumian 9 were used to study the fiber developmental characteristics and the effect of hormones on fiber quality with sampling different stages after anthesis. The results showed that fiber length of the brown and green cotton cultivar was lower than that of control, and that of the green cotton always lower than that of brown cotton. Compared with the control, the fiber strength, fiber micronaire, fiber maturation of natural-colored cotton were lower. The lower fiber length for the green cultivar was due to the less increase during 10 to 30 days post anthesis (DPA), the lower fiber strength, fiber micronaire, fiber maturation of natural-colored cotton were due to the slower growing speed at the pivotal stage. The IAA content at 10 DPA, the ABA content at 30 to 40 DPA in fiber of the two natural-colored cultivars were lower than that of Sumian 9. In comparison with control, in the treatment of applying 20 mg L^-1 GA₃, the IAA content in the fiber of Xiangcaimian 2 and Wanmian 39 at 20 DPA increased by 51.07% and 64.33%, respectively at boll opening stage, and fiber length also enhanced by 8.13% and 13.96%, respectively at boll open stage. The ABA content in fiber in the treatment applying 20 mg L^-1 ABA at 40 DPA increased by 38.96% and 24.40% for Xiangcaimian 2 and Wanmian 39 respectively. The fiber strength, fiber micronaire, fiber maturation also enhanced at the boll opening stage, especially for Wanmian 39. Those results suggest that endogenous hormones affect fiber quality, application of ABA and GA₃ with suitable concentration can increase the content of hormones in the natural-colored cotton fiber and advance the fiber quality, and the effect of different hormones are different.