Lintless mutant is a super-short fiber mutant in upland cotton only 4-8mm in fiber length and also named Ligon cotton controlled by one dominant gene Li1. Fiber ultrastructure of the mutant (Li1) and its wild type (li1) in situ and in vitro was observed under an electron microscope to understand its cytological characteristics during the fiber cell elongation. The results showed that the mutant fiber in situ had thinner cytoplasm, more small vacuoles, less mitochondria, Golgi apparatus and endoplasmic reticula, and there were more starch granules which were free or packed in the amyloplast beside the cell wall than that of wild type. It was indicated that scarcity of functional organelles and disability of transformation from starch to sugar might be associated with the fact that the mutant fiber cell was aborted too early to elongate into normal length. Mutant ovule in some media containing GA3 could produce a kind of huge callus that grew faster than normal ovules. The callus was covered with many white, loose, and semitransparent fiber-like cells that apt to get off from ovule. These fiber-like cells were multicellular fibers generated by cell division and had black dots just like pigment glands in the stem and leaf of cotton. There were lots of micro-tubes beside cytoplasm membrane of the multicellular fiber, which were thought to be primary preparation for second wall deposition of multicellular fiber. It was indicated that GA3 might induce the expression of gene(s) that kept inactive in the field condition and then stimulate the original fiber cell in vitro to undergo division again.

A glutathione S-transferase (GST) gene has been introduced into restorers of cytoplasmic male sterility in upland cotton (Gossypium hirsutum L.) using Agrobacterium-mediated transformation. A transgenic restorer, signed as 'Zheda strong restorer', which has strong restorability to male sterility, was selected from progeny plants of transformants. When compared with an American restorer 'DES-HAF277', the fertility restorability of 'Zheda strong restorer' to male sterility was been enhanced by 25.8% in the percentage of viable pollens of hybrid (sterile line

以白色棉、棕色棉和绿色棉的成熟纤维为材料，用有机溶剂（乙醇、乙醚、二甲苯），酸性、碱性溶液，以及HNO3/乙醇溶液，分别对不同颜色纤维中的色素进行提取. 结果表明，采用HNO3/乙醇溶液消煮法可以将彩色纤维中的色素物质提取出来。HNO3/乙醇的色素提取液在光谱波长为412nm处有一个最大吸收峰；颜色深浅不同的棕色或绿色棉纤维提取液在这一波长处的吸收值差异显著，随着纤维颜色的加深提取液吸收值增大（0.0634～0.9900）；白色纤维的提取液在412nm处的吸收值很小（0.0072），可忽略不计。因此，用HNO3/乙醇法提取棉纤维色素和用分光光度计比色法可以定量比较彩色棉纤维的色泽深浅。在用酸性和碱性处理棕色和绿色棉纤维时，发现纤维颜色的深浅程度随处理溶液酸碱度的变化而变化，而且这种变化是可逆的。纤维中色素含量与纤维素含量存在负相关。

以彩色棉纤维的颜色作为指示性状，在三系杂交棉的制种田，将带有指示性状的棕色棉恢复系或绿色棉恢复系按1:2的比例与白色棉不育系混合种植（混播制种方式），缩短蜜蜂等媒介在不育系棉株与恢复系棉株花朵间的传粉距离，利用天然媒介传粉提高杂交种子产量。试验以常规的条播制种方式为对照，发现混播制种方式可有效地提高不育系的结铃率和降低其棉铃的不孕籽率，制种产量比对照增加14%以上。这种混播制种方式，只要在棉花采收时，分收不同颜色籽棉就可区分杂交与自交的种子，如棕色不育系与白色恢复系的制种田中，棕色纤维种子即为杂交种子，白色纤维种子即为恢复系自交种子。因此，通过培育彩色棉雄性不育系或恢复系，利用其纤维颜色作为指示性状，采用混播制种方式可提高制种产量，在彩色棉杂交种子的生产中是可行的。

棕色和绿色纤维中的色素可用HNO3/乙醇提取，提取液中的色素含量可在412nm波长下根据吸收值的大小进行估计。在开花后15d前后，棕色和绿色纤维中的色素已经形成和积累，并在开花后20d色素含量达到最高值. 棕色纤维颜色发生明显加深的时期是开花后30～35d，棕色纤维的颜色较稳定，在阳光下甚至有加深的趋势。绿色棉纤维在开花后20d时纤维出现绿色，之后随着纤维的发育颜色逐渐加深，但在阳光下易退色。在棕色和绿色纤维中纤维素含量明显低于白色纤维，可能是由色素物质的积累所引起。在开花后15～30d期间，白色纤维细胞的pH值呈快速下降趋势，但棕色和绿色纤维细胞的pH值下降速度比白色纤维细胞明显要慢，在这一时期pH值下降速度的快慢可能与纤维的伸长、次生壁的加厚和色素的形成有关。与白色纤维比较，棕色和绿色纤维品质较差，如：长度偏短，强度偏低，其可能原因本文进行了探讨。