蜡梅‘美人醉’花色变化过程中生理生化特性研究

该研究以成年乔种蜡梅‘美人醉’[Chimonanthus praecox(L.)Link‘Meirenzui’]5个时期(蕾期、萌动期、初花期、盛花期和末花期)的花瓣内被片为材料,考察开花过程中花瓣色度值、花色素含量、可溶性蛋白含量、可溶性糖含量及其超氧化物歧化酶(SOD)、苯丙氨酸解氨酶(PAL)活性的变化,并探讨各指标之间的相关性,以揭示蜡梅花色变化过程中生理生化指标的变化特征。结果显示:(1)‘美人醉’花瓣的色度值从蕾期到末花期,花瓣红度a^(*)值急剧减小,亮度L^(*)值、黄度b^(*)值和彩度C^(*)值、色相角h°值逐渐增大。(2)在‘美人醉’开花过程中,花瓣类黄酮、花色苷、叶绿素含量逐渐减少,类胡萝卜素含量先增加后减少。(3)‘美人醉’花瓣可溶性蛋白含量在萌动期和盛花期显著下降,而可溶性糖含量在初花期降到最低值。(4)‘美人醉’花瓣PAL活性随着开花进程呈先下降后上升的趋势,而SOD活性先显著上升,后保持平稳。(5)‘美人醉’花瓣色度值与其类黄酮、叶绿素、花色苷、可溶性蛋白含量以及PAL活性均具有显著相关关系。研究表明,蜡梅‘美人醉’花色变化是花色苷、类黄酮、叶绿素共同作用的结果,但花色苷含量的变化起着最直接的作用;花瓣可溶性蛋白、SOD、PAL通过一定的生理代谢途径对花色变化起着间接的影响。     

不同种源黄连木秋季色素含量与叶色参数的关系

该研究以陕西汉中、河南林州、河北涉县和北京中国科学院植物研究所4个种源黄连木(Pistacia chinensis Bunge)的苗木为对象,用分光光度计和色差仪对其叶绿素、类胡萝卜素、花色素苷含量及叶色参数(L*、a*、b*)进行了测定分析,探讨不同种源苗木秋季叶色变化规律及差异,揭示黄连木叶色呈现与叶片色素含量之间的内在关联,为筛选适合城市绿化的优良黄连木种源提供依据。结果表明:(1)在秋季叶片转色期,随着时间的推移,4个种源黄连木叶片的叶绿素、类胡萝卜素和花色素苷含量的比例呈现不同的变化趋势,其中:河北种源的花色素苷含量较高,叶片呈现红色;陕西种源叶绿素含量较高,叶片呈现绿色的时间较长;河南、北京种源处于两者之间。(2)各个种源黄连木的叶色参数a*值(红/绿)均与花色素苷含量呈正相关关系,与叶绿素含量呈负相关关系,且相关系数均达到显著水平(P0.05),各个种源叶色参数L*值(光泽明亮度)也与叶绿素含量间表现出显著或极显著的正相关性。研究发现,河北种源黄连木秋季的叶色最红,陕西种源黄连木叶片呈现绿色的时间最长;色差仪的应用实现了叶色和各色素含量间量化的关系。     

枫香秋季变色期叶色变化及其生理基础

为探究秋季枫叶呈色的关键生理因素,该文以转色期叶色为绿色、黄色和红色的枫香单株为试材,研究了L^*、a^*、b^*值变化与叶片色素、可溶性糖及可溶性蛋白质含量变化的相关性。结果表明:(1)在变色期,3种色彩枫香叶片叶绿素a、叶绿素b、总叶绿素和类胡萝卜素均大量降解,花色素苷不同程度积累。(2)绿色叶单株叶绿素和类胡萝卜素始终保持较高含量,花色素苷含量上升4.2倍,叶片内色素含量比值始终保持稳定; 黄色叶单株叶绿素和类胡萝卜素含量最低,花色素苷含量上升4.4倍,b^*值与叶绿素含量极显著负相关,与类胡萝卜素含量显著负相关,与花色素苷/类胡萝卜素含量比值极显著正相关; 红色叶单株叶绿素和类胡萝卜素含量略高于黄色叶单株,花色素苷含量上升27.2倍,a^*值与叶绿素含量、类胡萝卜素含量极显著负相关,与花色素苷含量显著正相关,与色素含量比值无显著相关性。(3)红色叶单株具有较高的可溶性糖含量和可溶性蛋白质含量。因此,在枫香叶片变色期,保持较高的叶绿素和类胡萝卜素含量,维持色素含量比值稳定使叶片呈现绿色; 叶绿素和类胡萝卜素的大量降解,以及花色素苷/类胡萝卜素含量比值的升高使叶片呈现黄色; 叶绿素的降解和花色素苷的大量合成使叶片呈现红色。     

金叶复叶槭叶片色素与解剖结构

以金叶复叶槭(Acer negundo ‘Aurea’)的金黄叶、复绿叶为试验材料,以复叶槭的绿叶为对照(CK),测定并比较3种叶片类型的叶色参数、色素含量和解剖结构,探究金叶复叶槭叶片的呈色机理,为金叶植物叶色机理的研究及栽培提供理论依据。结果表明：金黄叶叶色参数L^*、a^*、b^*值极显著高于复绿叶和CK(P<0.01),复绿过程中叶色参数均呈下降趋势。金黄叶叶绿素a、叶绿素b、总叶绿素、类胡萝卜素含量极显著低于复绿叶和CK,ω(类胡萝卜素)/ω(总叶绿素)为0.64,极显著高于复绿叶和CK(P<0.01),复绿过程中色素含量均呈上升趋势。3种类型叶片横切面各组织厚度、比值及排列存在差异,金黄叶叶片厚度124.51μm,显著低于CK(P<0.05),栅栏组织厚度31.26μm、栅/海为0.45,均极显著低于复绿叶和CK(P<0.01),栅栏组织和海绵组织排列混乱,而另外2种类型叶栅、海组织排列较为规则有序。金黄叶叶绿体长、宽分别为3.42μm、1.27μm,均极显著小于复绿叶和CK(P<0....     

茶树种质叶片色素含量与叶色参数的关系

为了探究茶树种质资源叶片色素含量与叶色参数之间的关系,以143份黄、白化和紫化叶色特异茶树种质为材料,比较分析各种质叶片叶色参数L*、ɑ*、b*值和花青素、叶绿素、类胡萝卜素含量差异,并通过主成分分析、聚类分析、相关性分析、多元逐步回归分析和通径分析探讨叶片色素含量和叶色参数关系,为叶色特异茶树种质叶片呈色机理及品种选育提供依据。结果表明:(1)紫化茶树种质花青素含量和ɑ*值较高,叶片呈现紫红色;黄化种质类胡萝卜素含量/叶绿素含量比值和b*值较高,叶片呈黄色,白化种质L*值较高,叶片呈白色。在叶色表型性状方面,叶色特异茶树种质大体聚为两大类群,白色系和黄色系聚为一大类,紫色系聚为另一大类。(2)叶色特异茶树种质叶片叶色参数ɑ*值与花青素含量呈极显著正相关,L*值、b*值与花青素和叶绿素含量均呈极显著负相关,且b*值与类胡萝卜素含量呈极显著正相关;花青素、叶绿素对叶片CIEL*ɑ*b*值直接作用较大。总之,ɑ*值可作为描述叶色特异茶树种质叶片紫红色性状的代表性参数,b*值可作为描述叶色特异茶树种质叶片黄色性状的代表性参数。     

不同叶色三叶海棠叶片成色色素分析

三叶海棠秋季叶色丰富,观赏价值良好。该研究以三叶海棠叶色差异明显的绿色、黄色、红色系的叶片为材料,利用紫外—可见分光光度法、高效液相色谱法对色素进行了定性定量检测,并分析了叶色变化的原因。结果表明:三叶海棠叶片中的色素主要有叶绿素、类胡萝卜素和花青苷,其中花青苷主要是矢车菊素半乳糖苷。绿色系叶片中的叶绿素含量与所占比例显著高于红色和黄色系叶片,而花色素苷和类胡萝卜素所占比例均最小;红色系叶片中的花青苷含量高于其它色系的叶片,花青苷所占比例高于叶绿素与类胡萝卜素所占比例;黄色系叶片中类胡萝卜素含量相对较高,花色素苷和叶绿素所占比例位于绿色与红色系之间。该研究结果表明三叶海棠秋季叶色变化最直接的原因是色素含量与比例发生变化;叶片含有的原花青素B1、芦丁、绿原酸等单体酚作为辅色素对叶片成色起到辅助作用;三种色系叶片中的总黄酮含量由高到低依次为红色、黄色、绿色。     

金叶连翘叶片色素含量和解剖结构研究

金叶连翘不同冠层的成熟叶片呈现为不同颜色。以朝鲜连翘深绿色叶为对照,观察金叶连翘冠层上、中、下位叶色,测定其叶片大小和叶绿素a、叶绿素b、总叶绿素及类胡萝卜素含量,同时观察分析叶片横切面解剖结构,旨在阐明叶片色素含量和解剖结构对叶色的影响。研究表明:上层黄色、中层黄绿色、下层浅绿色,黄、黄绿、浅绿色叶总叶绿素含量分别是对照组的0.51%、4.44%和66.47%,均极显著低于对照(P <0.01),但黄绿叶的叶绿素a/b比值显著升高(P <0.05),黄、黄绿叶的总叶绿素/类胡萝卜素比值极显著降低(P <0.01)。黄、黄绿叶的叶绿体发育停滞于单片层时期,类囊体分化程度低,浅绿叶类囊基粒片层肿胀;黄叶细胞器降解,栅栏组织细胞形状难以辨别,黄绿叶上表皮细胞凸起。金叶连翘属于总叶绿素及叶绿素b合成减少型突变体,表现为叶绿素严重缺失,类胡萝卜素相对含量升高;其叶绿体发育停滞,类囊体结构异常,是金叶连翘叶片呈现不同颜色的主要因素,与其叶片解剖显微结构无关。     

南天竹和火焰南天竹叶色表型与色素含量变化研究

目的：探索南天竹和火焰南天竹叶色变化与生理生化指标之间的相关性。方法：以2年生南天竹和火焰南天竹植株为材料，进行叶色表型与色素含量的测定与分析。结果：南天竹叶片在10月至翌年2月表现出不同程度的红色，其余时间则呈现绿色。火焰南天竹叶片大部分时间表现为黄绿色，11月至翌年2月叶色发生变化；南天竹和火焰南天竹在5月至翌年3月叶片中叶绿素的含量变化呈现相同的趋势，6月南天竹叶片中叶绿素含量最高，火焰南天竹叶片中叶绿素含量在3月最高；1月南天竹叶片中类胡萝卜素含量最高，5月含量最低。火焰南天竹叶片中类胡萝卜素含量在3月最高，7月含量最低；11月南天竹叶片中花青素含量最高，而火焰南天竹叶片中花青素含量在2月最高。结论：在南天竹和火焰南天竹叶片发育的初期，外界温度低，诱导叶片大量合成花青素，使其呈现红色。随着环境温度的不断升高，叶片中叶绿素和类胡萝卜素逐步产生并积累到一定含量，叶片颜色由红色转变成绿色。     

叶面喷施水杨酸对3种色系榉树秋季叶片呈色的影响

以秋季转色期叶色表现为红色、黄色、绿色的3种色系榉树叶片为材料,通过不同浓度水杨酸叶面喷施处理,测定并分析其叶片的颜色参数及花青素、叶绿素等色素含量的变化。结果表明:喷施0.5 mmol·L~(-1)水杨酸能促进红色系榉树叶片花青素的合成,加速其叶绿素的降解,加深叶片红色程度;喷施0.5 mmol·L~(-1)水杨酸延长黄色系榉树的绿色期,推迟变色期;喷施1.0 mmol·L~(-1)水杨酸能使黄色、绿色系榉树叶片变黄,提前变色期。     

4种李属彩叶植物色素含量与叶色参数的关系

以4种李属彩叶植物紫叶李、紫叶矮樱、黑杆樱李和美人梅4年生嫁接苗为试材,对其叶绿素、类胡萝卜素、花色素苷含量及叶色参数(L·、a·、b·)进行了测定分析.结果表明:(1)随着季节的变化, 4种李属彩叶植物色素含量表现出基本相似的波动趋势,并以黑杆樱李的花色素苷含量在季节间较为稳定且极显著高于其他3种植物(P＜0.01),而美人梅的叶绿素、类胡萝卜素含量在在季节间较为稳定且显著低于其余植物(P＜0.05); 4种植物中各色素含量比例不尽相同且随着季节而变化,但黑杆樱李的比值较稳定且花色素苷比例始终最高,叶片保持紫红色,而美人梅的各色素比值变化较大,叶片呈现紫红-绿-红的变化过程.(2)4种李属彩叶植物的叶色参数(L·、a·、b·)也随季节发生波动,并以黑杆樱李相对稳定,美人梅的变化幅度较大,而且各树种之间的a·和b·值差异分别达到显著水平(P＜0.05)和极显著水平(P<0.01).(3)4种植物叶片 a·值与叶绿素含量、花色素苷含量均呈显著或极显著的正相关性,而L·值和b·值与叶绿素含量、花色素苷含量、类胡萝卜素含量的相关性因树种而异.研究发现,4种李属彩叶植物的色素含量及其比值随季节发生波动的幅度不尽相同,叶片花色素苷含量比例的高-低-高变化使叶色呈现红-绿-红的过渡;花色素苷含量和叶绿素含量的高低决定着a·值大小,但它们并不是影响L·和b·值的主要因素.     

Systematic significance of mature embryo of bamboos

The mature embryo of seven species belonging to five genera of Indian bamboos is described. In all these the basic pattern of embryo organisation is same: the scutellar and coleoptilar bundles are not separated by an internode, the epiblast is absent, the lower portion of the scutellum and the coleorhiza are separated by a cleft and the margins of embryonic leaves overlap. The features unique to fleshy fruited bamboos are: presence of a massive scutellum, the juxtaposition of plumule and radicle and the occurrence of a bud in the axil of the coleoptile. The fleshy fruit bearing bamboos should be classified into one group, the tribeMelocanneae. Evidence is provided to recognise additional groups in the subfamilyBambusoideae.     

Taxonomic status of the species of the green algal genusNeochloris

Komárek has recently reviewed the various species assigned to the green algal genusNeochloris Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia. Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class.     

Phylogeny of cardinalfishes (Teleostei: Gobiiformes: Apogonidae) and the evolution of visceral bioluminescence

The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.     

Host plants of someRhinanthoideae (Scrophulariaceae) of eastern North America

Twenty three species in 11 genera were examined in the field to determine hosts. OnlyStriga asiatica andSeymeria cassioides have a narrow host range being restricted to grasses and pines, respectively. These are the only species which cause pronounced and sometimes serious host damage. The other species attach to a great diversity of hosts.     

Apoptotic Regulation of Caspase Activity

Intracellular cysteine aspartate-specific proteases (caspases) play both signaling and effector roles in realizing the program of cell death. Caspases function as proteolytic cascades unique for each cell type and signal triggering apoptosis. All parts of the proteolytic cascades are duplicated and controlled by feedback signals. Amplification cycles between pairs of caspases (the third and the sixth, the ninth and the third, the twelfth and the sixth, and others) help multiply the initial apoptotic signal. The presence of physiological inhibitors of apoptosis that directly interact with caspases creates a multilevel regulatory network of apoptosis in cell. The caspase proteolytic cascades are also regulated by sphingolipid secondary messengers, among them ceramide, sphingosine, and their phosphates. Moreover, an association of the caspase signaling with ubiquitin-dependent proteolysis is shown in cells. In particular, the use of extracellular activators and inhibitors of caspases allows irreversible activation of apoptosis in tumor cells or the prevention of apoptosis in cortical neurons under neurodegenerative diseases.     

A molecular phylogeny of Hebeloma species from Europe

In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.     

Analysis of twin of eyeless regulation during early embryogenesis in Drosophila melanogaster

The Drosophila Pax6 homolog twin of eyeless (toy) is so far the first zygotically expressed gene involved in eye morphogenesis in Drosophila. The study of its expression during embryogenesis is therefore informative of the initial events of eye development in Drosophila. We have analyzed how the initial expression domain of toy at cellular blastoderm is regulated. We show that the three maternal patterning systems active in the cephalic region (the anterior, terminal and dorsal-ventral systems) cooperate with zygotically activated gap genes to shape the initial expression domain of toy. Whereas Bicoid, Dorsal and Torso signaling synergistically act as activators, Hunchback, Knirps and Decapentaplegic act as repressors.     

New species of Peruvian Orchidaceae III

Sixteen new species are proposed in the generaAckermania, Dressleria, Epidendrum, Maxillaria, Oncidium, Rodriguezia, Sigmatostalix, andTrigonidium. All new species are illustrated.Maxillaria vittariifolia L. O. Williams is newly recorded for Peru. A key is provided forTrigonidium of Peru.Trigonidium loretoense Schltr. andT. peruvianum Schltr. are lectotypified.     

Interaction of Synthetic Analogues of Natural Chalcones and Flavones with Guanidine

The reaction of chalcones and flavones with guanidine in ethanol results in 2-(2-aminopyrimidinyl-4)-phenols.     

Demographic characteristics of an intertidal bay goby (Lepidogobius lepidus)

Synopsis In a fourteen month study (May 1976 – June 1977) I examined the following characteristics of an intertidal bay goby (Lepidogobius lepidus) in Morro Bay, California, U.S.A.: annual and seasonal patterns of abundance, age composition and growth rates, survivorship and mortality patterns, and the reproductive cycle for female gobies. Fishes were collected with the aid of quinaldine and otoliths and ovaries removed. Age and growth rates were estimated from otolith annuli using a back calculation formula and a Brody-Bertalanffy growth curve. Mortality rates were derived using the methods of Heincke (1913), Robson & Chapman (1960), mean age, and a catch curve (Ricker 1975). A gonad index was used to describe the annual reproductive cycle. Results indicated that abundance fluctuated seasonally and that these fluctuations appeared to be caused by reproductive emigrations. Bay gobies reached an age of 7+ and a standard length of 87 mm. Growth was relatively constant (6 mm yr⁻¹) until age 5, at which point it began to decline. The mean rates of survivorship, mortality, and instantaneous mortality were 0.75, 0.25, and 0.29 respectively. Mortality rates for individual age classes ranged from 0.13 to 0.51 and increased with age. This stock appears to reproduce mainly during the winter.