【作者】 张美玲；

【导师】 孙学振； 王振林； 宋宪亮；

【作者基本信息】 山东农业大学 ， 作物栽培学与耕作学， 2013， 博士

【摘要】 彩色棉(Gossypium hirsutum L.)无需染色，绿色环保，具有广阔的发展前景。但是彩色棉纤维品质较差、颜色单调且不稳定，严重影响了彩色棉产品开发及产业化。本研究以不同颜色的棉花品种[棕色棉品种棕絮1号(ZX-1)和新彩棉1号(XC-1)；绿色棉品种陇绿棉2号(G-7)和绿1-4560(4560)；以及普通白色对照品种鲁棉研28(LMY28)]为材料，首先从形态学方面对纤维分化发育、色泽变化及色素沉积分布进行了观察；然后对彩色棉纤维品质形成进行了研究，并围绕彩色棉纤维品质与纤维超分子结构、纤维素含量、糖组分及矿质元素的含量和纤维发育相关酶活性的关系进行了研究；此外从代谢物水平对色素成分进行了系统研究。主要结果如下：1彩色棉纤维发育过程中纤维色泽的形成规律棕色棉ZX-1和XC-1的纤维色泽在开花后35d之前均随纤维的发育逐渐加深，开花后35~40d以及开花后55d~吐絮快速加深。而绿色棉G-7和4560的纤维色泽在开花后25～45d逐渐加深，并于开花后45d达到最大，开花后55d至吐絮变浅。2彩色棉纤维发育过程纤维色素的沉积分布规律在纤维发育过程中，ZX-1与G-7纤维色素的形成时间及在纤维内的沉积部位均存在差异。纤维色素在G-7的形成时间较ZX-1早，且沉积于纤维中腔和次生壁内层，而ZX-1仅沉积在纤维中腔内。3彩色棉纤维品质形成机理的研究3.1彩色棉纤维分化发育规律各供试品种胚珠中部的部分表皮细胞均于开花前1d开始分化；开花后当天，胚珠纤维细胞均有突起；开花后1d，纤维细胞突起增多，体积增大，其中LMY28的纤维细胞已有伸长的态势；开花后3d，纤维细胞均已伸长。除分化程度在各供试材料间差异不显著外，突起数量、发育和伸长程度，均以LMY28最优，ZX-1次之，G-7最差。3.2彩色棉纤维品质的形成各供试品种的纤维长度、3.2mm隔距比强度、成熟度和马克隆值均随棉纤维的发育呈增大的变化趋势。最终棉纤维长度、3.2mm隔距比强度、成熟度及马克隆值均表现为白色棉LMY28>棕色棉ZX-1和XC-1>绿色棉G-7和4560。3.3彩色棉纤维发育过程中超分子结构的动态变化及与纤维品质的关系各供试品种的横向晶粒尺寸均随纤维发育进程不断增大，取向参数逐渐减小(优化)，但不同品种间存在差异。彩色棉纤维的横向晶粒尺寸与3.2mm隔距比强度密切相关(r=0.8962*)，ψ角和φ角与3.2mm隔距比强度、成熟度、马克隆值呈显著负相关(r=0.9382*to0.9023*)，α角与纤维长度极显著负相关(r=0.9731**)。表明彩色棉纤维品质差与纤维发育过程中横向晶粒尺寸初始值和终止值低及取向参数终止值高，进而影响纤维3.2mm隔距比强度、成熟度、马克隆值和纤维长度有关。3.4彩色棉纤维发育过程中纤维素含量与糖组分及矿质元素含量的关系棉纤维发育过程中纤维素含量均呈“S”型曲线变化趋势。开花后25d之后，白色棉品种LMY28的纤维素含量极显著高于彩色棉品种ZX-1和G-7。果糖、葡萄糖、半乳糖、纤维二糖、N、P、K、S和Mg的含量是纤维素沉积必不可少的。表明，葡萄糖既是棉花纤维素生物合成的直接前体，又是纤维素生物合成的关键糖。彩色棉品种可能存在一种特殊机制：原本用于纤维素生物合成的碳水化合物(尤其是葡萄糖)和矿质元素(N、P、K、S和Mg)被用于纤维色素的生物合成和沉积，从而导致了纤维素含量彩色棉显著低于白色棉。3.5彩色棉纤维发育过程中相关酶活性彩色棉棉纤维发育过程中，纤维发育相关酶(蔗糖合成酶、β-1,3-葡聚糖酶、蔗糖酶、吲哚乙酸氧化酶和过氧化物酶)活性较白色棉低，影响了彩色棉纤维素的合成和沉积，进而影响了彩色棉优良纤维品质的形成。此外，棕色棉的磷酸蔗糖合成酶活性较白色棉和绿色棉高，但其纤维素含量较白色棉低，可能其磷酸蔗糖合成酶合成的蔗糖用于了纤维色素的合成，引起了纤维素的合成过程中能量的供应不足，导致彩色棉纤维素含量较白色棉低，进而影响了彩色棉优良纤维品质的形成。4彩色棉纤维色素的成分甲醇80℃索氏提取48h的色素样品，采用HPLC以甲醇:乙酸=98:2(v/v)为流动相进行分离，于285nm波长下检测分离的效果最佳。最后采用LC-MS对棕色棉ZX-1和绿色棉G-7色素甲醇提取液进行分离检测，其中棕色棉ZX-1和绿色棉G-7分别检测出7种和12种化合物，其均为黄酮类化合物。棕色棉ZX-1纤维色素经鉴定出的7种化合物分别为：无色花翠素-3-O-(β-D-吡喃葡萄糖基-(1→4)-α-L-吡喃鼠李糖苷、山奈酚3-(3’’-乙酰基-α-L-呋喃阿拉伯糖苷)-7-鼠李糖苷、芦丁、槲皮素、Piscerythramine、芹菜素-7-(6’’-丁烯酰基糖苷)、Pendulin。绿色棉G-7纤维色素经鉴定出的12种化合物分别为：柳穿鱼黄素-7-芸香糖甙、槲皮素-3-硫酸酯-7-α-阿拉伯吡喃糖苷、表没食子儿茶素-5,3’,5’-三甲基醚-3-O-没食子酸酯、山奈酚3-[6’’-(3-羟基-3-甲基戊二酰基)葡萄糖苷]、鹰嘴豆芽素A-7-O-芸香糖苷、槲皮素3,3’-二甲基醚-4’-异戊酸、异山奈素-7-芸香糖甙、Apigenin7-(2’’-glucosyllactate)、山奈酚-3-(3’’,4’’-双乙酰基葡萄糖苷)、槲皮素-3-木糖苷-7-葡萄糖苷、异鼠李素-3-O-β-D-2’’,3’’,4’’-三乙酰基吡喃葡萄糖苷、Cassiaoccidentalin A。彩色棉纤维色素成分中并不是每种成分都具有天然色泽，其中，棕色棉ZX-1纤维色素的化合物1和化合物5是无色的，其它化合物的颜色呈灰黄至黄色；绿色棉G-7纤维色素的化合物3和化合物5是无色的，其它化合物的颜色呈灰黄至黄色。彩色棉纤维色泽的表现可能依赖于纤维色素成分与纤维细胞中矿质元素的结合以及细胞质pH值的影响。更多还原

【Abstract】 Brown and green are the two most common fiber colors in colored cotton cultivars(Gossypium hirsutum L.). Although there are drawbacks to colored cotton, such as poorquality and the instability of the fiber pigments, colored cotton remains widely popularbecause it is environment-friendly, economical, and beneficial to human health. In order toexplore the formation of fiber pigment and the relationship between fiber pigment and fiberquality and color stability in colored cotton cultivars, the experiments were conducted withdifferent cotton cultivars, including brown cotton cultivars (ZX-1and XC-1), green cottoncultivars (G-7and4560), and white cotton cultivar (LMY28). The regulation of fiberdifferentiation and development and the related metabolism of physiological and biochemical,the dynamic changes of supramolecular structure and fiber color, as well as, the distributionand composition of fiber pigments in fiber development process of colored cotton weresystematic studied by the combining methods of morphology, physiological and biochemicalmeasurements, and metabolomics. The main results were as follows.1Patterns of color formation in different fibers during development of colored cottoncultivarsThe fiber color of brown cultivars gradually deepened before35days post anthesis(DPA), rapidly deepened from35DPA to40DPA, and from55DPA to maturation, whilegreen cultivars gradually deepened from25DPA to45DPA, reached a maxima at45DPA,and then faded from55DPA to maturation.2Regulation of pigment deposition in colored cotton fibers during developmentPigment forming time and depositing position showed significant differences in thefibers development process of ZX-1and G-7’s. That is to say, the pigment formation of G-7isearlier than that of ZX-1, and the pigment of G-7deposited in both lumen and the innersecondary wall, while the pigment of ZX-1only deposited in lumen. 3Mechanism of fiber quality formation in colored cotton cultivars3.1Regulation of differentiation in colored cotton fiberThe central part of the ovule epidermal cells began to differentiate at1DPA. There wereprotuberances of ovule fiber cells at0DPA. The number and volume of protuberancesincreased at1DPA, when the fiber cells of LMY28had the elongated trends. In addition,fiber cells already elongated at3DPA. In summary, LMY28was the best, followed by ZX-1,and G-7was the worst in the degree of differentiation, the number of protuberance, and thelevel of development and elongation.3.2Fiber quality formation of colored cotton cultivarsFiber length,3.2mm gauge strength, fiber maturation and fiber micronaire was increasedwith the development of the cotton fiber. The results showed that the ultimate fiber length,fiber3.2mm gauge tenacity, fiber maturation and fiber micronaire of all cotton cultivarsranked as LMY28> ZX-1and XC-1> G-7and4560.3.3Relationship between super-molecular structure changes and fiber quality in fiberdevelopment process of colored cotton cultivarsThe corresponding crystalline grain size increased constantly and orientation parametersdiminished gradually in fiber development process, but there were differences amongdifferent cultivars. The crystalline grain size had a correlation with3.2mm gauge tenacity (r=0.8962*), as well as, the orientational distribution angle-ψ () a nd spiral angle-φ () had anegative correlation with fiber3.2mm gauge tenacity, fiber maturation and fiber micronaire(r=0.9382*to0.9023*), moreover, the orientational separate angle-α () had a negativecorrelation with fiber length (r=0.9731**). In conclusion, the poor quality of colored cottonfiber is probably in relation to poor fiber3.2mm gauge tenacity, fiber maturation, fibermicronaire, fiber length, resulting from low initial value and termination value of crystallinegrain size and high termination value of orientation parameters in fiber development process.3.4The relationship between cellulose content and the contents of sugars and mineralsduring fiber development in colored cotton cultivarsCellulose contents during fiber development changed along S-shaped curves among thetested cotton cultivars. The cellulose content was significantly higher in the white cottoncultivar LMY28than in the colored cotton cultivars ZX-1and G-7after25DPA. Sugar and mineral contents showed significant changes during fiber development. Fructose, glucose,galactose, cellobiose, nitrogen, phosphorus, potassium, sulfur, and magnesium contents wereessential for cellulose deposition during fiber development. In this study, glucose was shownto be a direct precursor and key sugar in cellulose biosynthesis in cotton cultivars. There maybe a special mechanism in colored cotton cultivars that greater amounts of total carbohydrates,especially glucose, and minerals (nitrogen, phosphorus, potassium, sulfur, and magnesium)were consumed by the biosynthesis and deposition of fiber pigments than in the biosynthesisof cellulose. This finding could explain why the cellulose content was significantly lower inthe colored cotton cultivars than in white cotton.3.5The activity changes for enzymes associated with fiber development in coloredcotton cultivarsThe activity of enzymes associated with fiber development (sucrose synthase, β-1,3-glucanase, invertase, indoleasetic acid oxidase, and peroxidase) in colored cotton cultivarswere less than in white cotton cultivar. Effecting the cellulose biosynthesis and the formationof fiber quality of colored cotton. In addition, the activity of sucrose phosphate synthase incolored cotton cultivars was higher than in white cotton cultivar. As well as, the cellulosecontent of colored cotton was lower than white cotton, may be the sucrose was used for thefiber pigment biosynthesis, causing the short supply of energy in the process of the cellulosebiosynthesis. Resulting in the cellulose content in colored cotton was lower than white cottonand affecting the fiber quality formation in colored cotton.4The fiber pigment composition in colored cottonAccording to the extraction method and the separation and detection of component, wefound the best fiber pigment was extracted48h by Soxhlet extraction of methanol in waterbath at80°C. Fiber pigment in different colored cotton cultivars were separated, identified,and quantified by a high-performance liquid chromatographic method with photodiode arrayand mass spectrometric detection (LCMS). Compound of fiber pigment are flavonoids inbrown cotton ZX-1and green cotton G-7, including7compound and12compound,respectively. Seven compounds were identified by LCMS in brown cotton ZX-1, as follows.Leucodelphinidin3-O-(β-D-glucopyranosyl-(1→4)-α-L-rhamnopyranoside), Kaempferol3-(3’’-acetyl-α-L-arabinofuranoside)-7-rhamnoside, Rutin, Quercetin, Piscerythramine,Apigenin7-(6’’-crotonylglucoside), Pendulin. Twelve compounds including Pectolinarigenin7-rutinoside, Quercetin3-sulfate-7-α-arabinopyranoside, Epigallocatechin5,3’,5’-trimethyl ether3-O-gallate, Kaempferol3-[6’’-(3-hydroxy-3-methylglutaryl) glucoside], Biochanin A7-O-rutinoside, Quercetin3,3’-dimethylether4’-isovalerate, Isokaempferide7-rutinoside, Apigenin7-(2’’-glucosyllactate),Kaempferol3-(3’’,4’’-diacetylglucoside), Quercetin3-xyloside-7-glucoside, Isorhamnetin3-O-β-D-2’’,3’’,4’’-triacetylglucopyranoside, and Cassiaoccidentalin A, were identified by LCMS ingreen cotton G-7. Meanwhile, the compound1and compound5was colorless, the othercompounds were grayish yellow to yellow of pigment composition in brown cotton ZX-1; thecompound3and compound5was colorless, the other compounds were grayish yellow toyellow of pigment composition in green cotton G-7, respectively. That is to say, the fibercolor of colored cotton may depend on the combination fiber pigment composition andminerals, as well as, the cytoplasmic pH value in fiber cells.更多还原