333 resultados para flower-color variation


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The effect of C-12(6+) heavy ions bombardment on mutagenesis in Salvia splendens Ker-Gawl. was studied. Dose-response studies indicated that there was a peak of malformation frequency of S. splendens at 200 Gy. Abnormal leaf mutants of the bileaf, trileaf and tetraleaf conglutination were selected. Meanwhile, a bicolor flower chimera with dark red and fresh red flower was isolated in M1 generation of S. splendens. Random amplified polymorphic DNA (RAPD) analysis demonstrated that DNA variations existed among the wild-type, fresh and dark red flower shoots of the chimera. The dark red flower shoots of the chimera were conserved and cultivated at a large-scale through micropropagation. MS supplemented with 2.0 mg/L BA and 0.3 mg/L NAA was the optimal medium in which the maximum proliferation ratio (5.2-fold) and rooting rate (88%) were achieved after 6 weeks. Our findings provide an important method to improve the ornamental quality of S. splendens.

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基因型变异和表型变异的相互关系问题是尚未解决的生物学基本问题之一,而解决这个问题的一个有效方法是研究基因组中功能相关基因的分子进化和表型效应的相互关系。在本研究中我们利用圆叶牵牛花青素代谢途径(该途径合成了与花色形成有关的色素)来研究表型变异和基因型变异的进化关系,希望探讨两个问题:1、代谢途径上基因多态性在不同位点的表现程度如何? 2、在中国种群中传粉者对花色有无选择? 在对第一个问题的研究中调查了中国圆叶牵牛花青素代谢途径部分结构基因和调控基因的多态性。所研究的结构基因为途径的第一个关键酶基因CHS-D基因和较下游的ANS基因、UF3GT基因,以及调控基因W位点。其次是在温室中进行人工自交以获得所研究基因的纯合体。在对第二个问题的研究中,首先调查了野外圆叶牵牛不同花色的传粉者和传粉几率,其次是分析有色花个体与白花个体中的遗传变异程度。目前的研究结果表明CHS-D位点有3个等位基因,其中在中国的西南部地区发现了1个新的、在已报道的7个等位基因以外的等位基因;较下游的结构酶基因ANS位点存在有5个等位基因(在中国新发现3个等位基因);UF3GT位点目前只发现有2个已报道的等位基因。在中国的圆叶牵牛中,新发现调控基因W位点上一个有功能的等位基因Ipmyb2,它与已报道的等位基因Ipmyb1的差异主要存在于内含子部分,而与发生缺失(1个6bp的缺失和1个19bp的缺失)后无功能的等位基因ipmyb2(该基因造成白花)存在外显子部分的8个碱基的差异。野外传粉观察结果表明,白花个体与有色花个体受到传粉者介导的选择,传粉者偏爱有色花而歧视白花,而且与在美洲不同,在中国圆叶牵牛的主要授粉者为蛾类而不是蜂类,从野外观察统计的结果看蛾类的传粉效率要高于蜂类。以上结果表明:1)花青素代谢途径上酶基因的位点均有一定程度的多态,其中尤以ANS为最高;调控基因ipmyb2的核苷酸缺失造成该基因停止功能,使其纯合子的个体开白色花。2)授粉者所介导的花色表型选择确实在中国种群中发生,有可能进一步增加花色代谢途径上基因位点的遗传变异。

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用生物和非生物因子来进行采后病害的防治,是一个非常有效的方法。诱导抗性作为控制果蔬采后病害的生物技术,已成为该领域的一个研究热点。然而诱导抗性的机制非常复杂,涉及到寄主、病原菌、激发子之间的相互作用关系。本研究主要利用酵母拮抗菌Pichia membranefaciens和SA处理果实,观察其抗性诱导表达和对采后青霉病菌(Penicillium expansum)的抑制作用,并从蛋白质组学水平上对诱导抗性的机理进行了分析。研究结果表明: 1、酵母拮抗菌P. membranefaciens (5 × 107 cells·ml-1)和SA(0.5 mM)处理采后甜樱桃果实,能够明显地降低病害的发病率和病斑直径。酵母菌和SA处理影响到了果实抗氧化酶的活性,同时还改变了POD同工酶谱和甜樱桃果实的总蛋白含量,并诱导了新的蛋白质条带产生。用光学显微镜和扫描电子显微镜技术观察发现,在in vitro条件下P. membranefaciens能够紧密地结合与病原菌的菌丝,而在in vivo条件下这种结合较为松散。 2、借鉴其它模式植物的方法,我们建立了一整套适用于多汁类植物材料的蛋白质组学研究方法。对于芒果,桃,甜樱桃、苹果以及冬枣等果实,都取得了重复性非常好的2-D图谱。我们应用该技术进一步研究了P. membranefaciens (1 × 108 cells·ml-1)以及SA (0.5 mM)处理对桃果实蛋白质组的诱导影响。结果显示,两种激发子处理都能够诱导桃果实产生抗性,从而减轻青霉病引起的腐烂。在诱导处理1 d以后,酵母拮抗菌和SA分别诱导22和16个蛋白的差异表达。质谱鉴定的蛋白属于6大类:代谢,防御反应,转录,能量途径以及细胞结构。有6个蛋白受到两种激发子的共同调控。其中,4种蛋白(包括glutathione peroxidase, polyphenol oxidase precursor, catalase和methionine sulfoxide reductase) 属于抗氧化蛋白,涉及到活性氧代谢。另2个蛋白(Major allergen Pru av 1和peroxidase)是病程相关蛋白,直接参与植物的防御反应。同时一些磷酸化酶和转录因子也受到两种激发子的调节从而参与果实的抗病反应。酶学测定和Northern杂交的结果表明,拮抗菌与SA处理均能影响过氧化氢酶活性及其基因的表达。 3、采前用较高浓度SA (2 mM) 短时间(10s)处理不同成熟期的甜樱桃果实,能够明显降低果实青霉病的病斑直径,并能减轻较低成熟度果实的发病率。在没有接菌的情况下,SA诱导了33个差异表达的蛋白,其中用质谱鉴定出了26个。而在接种病原菌的情况下,SA诱导了19个差异表达的蛋白,并鉴定出了其中的12个。这些蛋白分别涉及到代谢、防御反应、转录、能量途径、信号转导等过程。在没有接种病原菌的情况下,SA处理诱导了Putative DnaJ heat shock protein, PR1-like protein, Peroxidase, Major allergen Pru av 1 (Pru a 1)和Catalase等与抗病有关的蛋白。而在接种病原菌的情况下,诱导了PR1-like protein, Peroxidase和Catalase蛋白的差异表达。通过酶活性测定以及对细胞学定位的研究,我们发现在没有接种病原菌的情况下,POD的活性受到SA的诱导。但是在接种病原菌以后,诱导效果不明显。

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Molluscan shells may display a variety of colors, which formation, inheritance, and evolutionary significance are not Well understood. Here we report a new variant of the Pacific abalone Haliotis discus hannai that displays a novel orange shell coloration (O-type) that is clearly distinguishable from the Wild green-shelled abalone (G-type). Controlled mating experiments between O- and G-type abalones demonstrated apparent Mendelian segregations (1:1 or 3:1) in shell colors in F-2 families, which support the notion that the O- and G-types are under strict genetic control at a single locus With a recessive o (for orange shell) allele and a dominant G (for green shell) allele. Feeding with different diets caused modifications of shell color within each genotype, ranging from orange to yellow for O-type and green to dark-brown for the G-type, without affecting the distinction between genotypes. A previously described bluish-purple (B-type) shell color was found in one of the putative oo X oG crosses, suggesting that the B-type may be it recessive allele belonging to the same locus. The new O-type variant had no effect on the growth of Pacific abalone on the early seed-stage. This Study demonstrates that shell color in Pacific abalone is subject to genetic control as well as dietary modification, and the latter probably offers selective advantages in camouflage and predator avoidance.

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观赏向日葵作为一种新型花卉,具有巨大的市场开发潜力。而花色作为向日葵的重要观赏性状之一,对其的研究却比较少。本文从向日葵花色多样性、花色遗传规律、花色与虫媒传粉的关系及其对向日葵花色遗传的影响做了分析和讨论,利用英国皇家园艺学会比色卡和分光色差仪对向日葵的花色做了归类总结,并且利用高效液相色谱法对向日葵的花青苷成分做了分析研究。 本研究结果表明,彩色向日葵色系可以分为两大类,即黄色系和红色系,其中红色系向日葵的花色变异较小;而黄色系向日葵的花色变异较大,可以再细分为橙黄色和柠檬黄色两个亚类。利用高效液相色谱法测定了39份向日葵舌状花瓣中的花青苷大概有9种(A、B、C、D、E、F、G、H、I),这9种花青苷并不是在所有39份样品中都出现,且红色系向日葵中花青苷的种类较多。花青苷G在红色系和黄色系向日葵中均被检出。对红色向日葵花瓣的花青苷提取液进行多级质谱分析发现,花青苷元类型主要是矢车菊苷元,其糖苷类型主要是和葡萄糖、鼠李糖和/或阿拉伯糖结合;而在纯黄色的向日葵中通过多级质谱分析未检测到这些花青苷,说明矢车菊类花青苷是红色向日葵舌状花红色形成的化学基础。

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为了掌握欧报春各花色遗传规律服务于良种生产,通过对欧报春各色花进行色素吸收光谱和薄层层析分析,进行不同花色杂交研究,分析了欧报春各色花所含色素类型及各花色遗传规律。结果显示欧报春群体含多种花色素,单株也可含有多种花色素,形成多变的粉色、红色及蓝色花。黄色深浅主要由类胡萝卜素含量决定。白色对粉色及黄色为隐性遗传,黄色、粉色为显性遗传并有数量遗传特征,黄色与粉色独立遗传。蓝色为多基因控制的隐性遗传,并具有数量遗传特征。

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By introducing an effective electron injection layer (EIL) material, i.e., lead monoxide (PbO), combined with the optical design in device structure, a high efficiency inverted top-emitting organic light-emitting diode (ITOLED) with saturated and quite stable colors for different viewing angles is demonstrated. The green ITOLED based on 10-(2-benzothiazolyl)-1, 1, 7, 7-tetramethyl-2, 3, 6, 7-tetrahydro-1H, 5H, 11H-[1] benzopyrano [6, 7, 8-ij] quinolizin-11-one exhibits a maximum current efficiency of 33.8 cd/A and a maximum power efficiency of 16.6 lm/W, accompanied by a nearly Lambertian distribution as well as hardly detectable color variation in the 140 forward viewing cone. A detailed analysis on the role mechanism of PbO in electron injection demonstrates that the insertion of the PbO EIL significantly reduces operational voltage, thus greatly improving the device efficiency.

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Melanocortin-1 receptor (MC1R) plays a major role in pigmentation in many species. To investigate if the MC1R gene is associated with coat color in water buffalo, the coding region of MC1R gene of 216 buffalo samples was sequenced, which included 49 black river buffalo (Murrah and Nili-Ravi), 136 swamp buffalo (Dehong, Diandongnan, Dechang, Guizhou, and Xilin) with white and gray body, and 31 hybrid offspring of river buffalo Nili-Ravi (or Murrah) and swamp buffalo. Among the three variation sites found, SNP684 was synonymous, while SNP310 and SNP384 were nonsynonymous, leading to p.S104G and p.I128M changes, respectively. Only Individuals carrying homozygote E-BR/E-BR were black. The genotype and phenotype analysis of the hybrid offspring of black river buffalo and gray swamp buffalo further revealed that the river buffalo type allele E-BR or the allele carrying the amino acid p.104S was important for the full function of MC1R. The in silico functional analysis showed that the amino acid substitutions p.G104S and p.M128I had significant impact on the function of MC1R. Above results indicate that the allele E-BR or the allele carrying the amino acid p.104S was associated with the black coat color in buffalo.

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Plant traits and individual plant biomass allocation of 57 perennial herbaceous species, belonging to three common functional groups (forbs, grasses and sedges) at subalpine (3700 m ASL), alpine (4300 m ASL) and subnival (>= 5000 m ASL) sites were examined to test the hypothesis that at high altitudes, plants reduce the proportion of aboveground parts and allocate more biomass to belowground parts, especially storage organs, as altitude increases, so as to geminate and resist environmental stress. However, results indicate that some divergence in biomass allocation exists among organs. With increasing altitude, the mean fractions of total biomass allocated to aboveground parts decreased. The mean fractions of total biomass allocation to storage organs at the subalpine site (7%+/- 2% S.E.) were distinct from those at the alpine (23%+/- 6%) and subnival (21%+/- 6%) sites, while the proportions of green leaves at all altitudes remained almost constant. At 4300 m and 5000 m, the mean fractions of flower stems decreased by 45% and 41%, respectively, while fine roots increased by 86% and 102%, respectively. Specific leaf areas and leaf areas of forbs and grasses deceased with rising elevation, while sedges showed opposite trends. For all three functional groups, leaf area ratio and leaf area root mass ratio decreased, while fine root biomass increased at higher altitudes. Biomass allocation patterns of alpine plants were characterized by a reduction in aboveground reproductive organs and enlargement of fine roots, while the proportion of leaves remained stable. It was beneficial for high altitude plants to compensate carbon gain and nutrient uptake under low temperature and limited nutrients by stabilizing biomass investment to photosynthetic structures and increasing the absorption surface area of fine roots. In contrast to forbs and grasses that had high mycorrhizal infection, sedges had higher single leaf area and more root fraction, especially fine roots.

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Cowper-Symonds and Johnson-Cook dynamic constitutive relations are used to study the influence of both strain rate effect and temperature variation on the material intrinsic length scale in strain gradient plasticity. The material intrinsic length scale decreases with increasing strain rates, and this length scale increases with temperature.

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The theory of the loading/unloading response ratio (LURR) was applied to the Jiashi earthquake sequence which occurred at the beginning of 1997 in Xinjiang, and found that, before the earthquakes with relatively high magnitudes In the sequence, the ratio showed anomalies of high values. That is to say, the LURR theory can be applied to the short-term earthquake prediction in some cases, especially in the early period after a strong earthquake, such as the forecasts for some strong earthquakes in the Jiashi sequence.

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Turbulent air flows over developing wind waves in the air-sea boundary layer are numerically simulated without considering wave breaking. Influences of wind waves on air flows are considered using a model of significant wave and surface roughness, with a formula proposed for calculating the surface roughness, k - epsilon model is adopted to simulate turbulent flows. The results of the drag coefficient and turbulence characteristics agree well with the observations.

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Under the environment of seawater, durability of concrete materials is one of the chief factors considered in the design of structures. The decrease of durability of structures is induced by the evolution of micro-damage due to the erosion of chlorine and sulfate ions, which is characterized by the reduction of modulus, strength, and toughness of the material. In this paper, the variation of the flexural strength of cement mortar under sulfate erosion is investigated. The results obtained in present work indicate that the erosion time, concentration of sulfate solution, and water-to-cement ratio will significantly affect the flexural strength. Crown Copyright (c) 2008 Published by Elsevier Ltd. All rights reserved.