81 resultados para Lotus-japonicus


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In recent years, bivalve feces and powdered algae have been used as the food sources of holothurians in China. In this study, growth and energy budget for sea cucumber Apostichopus japonicus (Selenka) with initial wet body,veights of 32.5 1.0 g (mean +/- SE, n=45) when fed with five different granule diets containing dried bivalve feces and/or powdered algae in water temperature 13.2-19.8 degrees C and salinity 30-32ppt were quantified in order to investigate how diets influence growth and energy distribution and to find out the proper diet for land-based intensive culture of this species. Results showed that diets affected the food ingestion, feces production, food conversion efficiency and apparent digestive ratios, hence the growth and energy budget. Sea cucumbers fed with dried feces of bivalve showed poorer energy absorption, assimilation and growth than individuals fed with other four diets; this could be because feces-drying process removed much of the benefits. Dried bivalve feces alone, therefore, were not a suitable diet for sea cucumbers in intensive cultivation. The mixed diets of feces and powered algae showed promising results for cultivation of sub-adult Apostichopus japonicus, while animals fed with powdered algae alone, could not obtain the best growth. According to SGR of tested animals, a formula of 75% feces and 25% powdered algae is the best diet for culture of this species. Extruded diets were used in the present experiment to overcome shortcomings of the traditional powdered feeds, however, it seems a conflict exists between drying bivalve feces to form extruded diets and feeding sea cucumbers with fresh feces which contain beneficial bacteria. Compared with other echinoderms, in holothurians the energy deposited in growth is lower and the energy loss in feces accounts for the majority of the ingested energy. Such detailed information could be helpful in further development of more appropriate diets for culture of holothurians. (c) 2006 Elsevier B.V. All rights reserved.

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Suspension aquaculture of filter-feeding bivalves has been developing rapidly in coastal waters in the world, especially in China. Previous studies have demonstrated that dense populations of filter-feeding bivalves in shallow water can produce a large amount of faeces and pseudofaeces (biodeposits) that may lead to negative impacts on the benthic environment. To determine whether the deposit feeder Stichopus (Apostichopus) japonicus Selenka can feed on bivalve biodeposits and whether the sea cucumber can be co-cultured with bivalves in suspended lantern nets, three experiments were conducted, two in tanks in the laboratory and one in the field. In a 3-month flow-through experiment, results showed that sea cucumbers grew well with specific growth rate (SGR) reaching 1.38% d(-1), when cultured in the bottom of tanks (10 m(3) water volume) where scallops were cultured in suspension in lantern nets. Moreover, results of another laboratory experiment demonstrated that sea cucumbers could survive well on bivalve biodeposits, with a feeding rate of 1.82 +/- 0.13 g dry biodeposits ind(-1) d(-1), absorption efficiency of organic matter in biodeposits of 17.2% +/- 5.5%, and average SGR of 1.60% d(-1). Our longer-term field experiments in two coastal bays (Sishili Bay and Jiaozhou Bay, northern China) showed that S. japonicus co-cultured with bivalves also grew well at growth rates (0.09-0.31 g wet weight ind(-1) d(-1)) depending on individual size. The results suggest that bivalve lantern nets can provide a good habitat for sea cucumbers; and the co-culture of bivalve molluscs with sea cucumbers may provide an additional valuable crop with no additional inputs. (c) 2006 Elsevier B.V. All rights reserved.

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Supercritical fluid extraction (SFE) was used to extract homoisoflavonoids from Ophiopogon japonicus (Thunb.) Ker-Gawler. The optimization of parameters was carried out using an orthogonal test L-9 (3)(4) including pressure, temperature, dynamic extraction time and the amount of modifier. The process was then scaled up by 100 times with a preparative SFE system under the optimized conditions of 25 MPa, 55 degrees C, 4.0 h and 25% methanol as a modifier. Then crude extracts were separated and purified by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of n-hexane/ethyl acetate/methanol/ACN/water (1.8:1.0:1.0:1.2:1.0 v/v). There three homoisoflavonoidal compounds including methylophiopogonanone A 6-aldehydo-isoophiopogonone A, and 6-formyl-isoophiopogonanone A, were successfully isolated and purified in one step. The collected fractions were analyzed by HPLC. In each operation, 140 mg crude extracts was separated and yielded 15.3 mg of methylophiopogonanone A (96.9% purity), 4.1 mg of 6-aldehydo-isoophiopogonone A (98.3% purity) and 13.5 mg of 6-formyl-isoophiopogonanone A (97.3% purity) respectively. The chemical structure of the three homoisoflavonoids are identified by means of ESI-MS and NMR analysis.

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Acute peristome edema disease (APED) is a new disease that broke out in cultured sea cucumber along the Shangdong and Liaoning province coasts in China, PR, and has caused a great deal of death in Apostichopus japonicus (Selenka) since 2004. Here we report virus-like particles found in intestine epithelium of sea cucumbers reared in North China. It is the first time that sea cucumbers are reported to be infected by virus. Histological examinations showed that the viral inclusion bodies existed in intestine epithelium cells. Electron microscopic examinations show that the virions were spherical, 80-100 nm in diameter, and composed of a helical nucleocapsid within an envelope with surface projections. Detailed studies on the morphogenesis of these viruses found many characteristics previously described for coronaviruses. Virus particles always congregated, and formed a virus vesicle with an encircling membrane. The most obvious cellular pathologic feature is large granular areas of cytoplasm, relatively devoid of organelles. Tubular structures within virus-containing vesicles, nucleocapsid inclusions, and double-membrane vesicles are also found in the cytopathic cells. No rickettsia, chlamydia, bacteria, or other parasitic organisms were found. (c) 2007 Elsevier Inc. All rights reserved.

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In this study, the intestinal microbiota of kuruma shrimp (Marsupenaeus japonicus) was examined by molecular analysis of the 16S rDNA to identify the dominant intestinal bacteria and to investigate the effects of Bacillus spp. on intestinal microbial diversity. Samples of the intestines of kuruma shrimp fed normal feed and Bacillus spp. amended feed. PCR and denaturing gradient gel electrophoresis (DGGE) analyses were then performed on DNA extracted directly from the guts. Population fingerprints of the predominant organisms were generated by DGGE analysis of the universal V3 16S rDNA amplicons, and distinct bands in the gels were sequenced. The results suggested that the gut of kuruma shrimp was dominated by Vibrio sp. and uncultured gamma proteobacterium. Overall, the results of this study suggest that PCR-DGGE is a possible method of studying the intestinal microbial diversity of shrimp.

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本论文对沿阶草族Ophiopogoneae(Endl.)Kunth的研究历史作了回顾,从染色体、形态学和解剖学角度对此族作了研究,并作了数值分类和分支 系统学分析的尝试,在此基础上探讨了这个族的系统学问题. 1)本论文对此族三属37种123居群的染色体数目、基数及核型不对称性作了研究,其中19种的染色体为首次报道.它们是:P.macrostegiaHance, P.yunnanensis Wang et Tang,P.ophiopogonoides Wang et Tang,O. sarmentosus Wang et Dai,O.tienensis Wang et Tang, O.sylvicola Wang et Tang, O.fooningensis Wang et Dai, O.mairei L6vl.,O.szechuanensis Wang et Tang, O.angustiatus (Wang et Tang) S.C.Chen, O.amblyphyllus Wang et Dai,O.clavatus Wright ex Oliver,O.clivioidesD.M.Zhang et Hong, O.longiscaposus D.M.Zhang et Hong,O.umbraticola Hance,O.fuiD.M.Zhang ntHong,O.zingiberaceus Wang et Dai,O.gangxiensisd.M.Zhang et Hong,O. lo fouense L6vl. 2)在此族中首次报道了2n = 2x = 34的异基数二倍体,同时在O.umbraticola,O.japonicus,O.cLarkei中报道了2n=68的异基数二倍体,过核型和减数分裂等证明异基数是在二倍体水平上形成,并发展成倍性系列的. 3)在此族中首次报道了B染色体的存在,已确证了两种(P.macrostegia和D.tienensis).一种尚需进一步确证(O.Larkei). 4)通过对随体位置的系统研究,发现在此族中随体位置具有分类价值. 5)通过对8个种内多倍体、4个多倍体种的研究,表明多倍体分布于较北、海拔较高的地方,而亚洲热带地区的种,则无多倍体,同时在具异基数种类和核型较不对称种类上亦有这种分布特征;在确定了分布的多度中心的基础上,提出喜马拉雅_横断山脉到川西、川南一带是沿阶草属和山麦冬属的近代分化中心. 6)通过染色体结构和数目几个角度的研究,表明球子草属与其他两属在。染色体水平上已发生很大分化,但其属内的分化则不表现在染色体上.其他二属内部则有基数、倍性和核型不对称方面的分化.综观此族,染色体具有由核 型对称向不对称、由二倍体向多倍体、由种内多倍体向多倍体种,由单一基数向种内异基数几个方向进化的趋势. 7)通过对此族的形态观察和分析,提出茎或根状茎分枝方式是属下分类的重要依据;认为本族植物的花序是由圆锥花序简化而来,但残留着圆锥花序特征;并提出了本族花、茎、叶、根几个方面的形态演化趋势. 8)通过对此族二属21种的子房解剖,发现三属均有半下位子房,因而认为子房半下位作为分属检索性状是不合适的.此外还观察到子房着生位置在种内亦有变异,对这种变异的意义进行了探讨. 9)通过此族三属46种2变种的数值分类处理,表明本族由球子草群和沿阶草一山麦冬群两大类群组成,山麦冬属仅是与沿阶草属一个组(葶花组)并列的分类单元,其内部分化较小,而沿阶草属则较大. 10)通过46个性状计算了山麦冬属和沿阶草属共6个广布的“群内总体相 似度”(IOS),表明山麦冬属3个种种内个体之间、种间个体之间的分化很小,且可能有杂交现象,结合染色体资料和分布特征,认为这个属的发生是个相当晚近的事件. 11)本文从形态和染色体角度,认为沿阶草族是一个自然类群;由分支系 统学分析表明,此族由二个单系类群(球子草属和沿阶草属)组成,沿阶草属含两个单系的组,其中各含3个系,山麦冬属为其中一个系.这一结果与数值 分类结果和染色体资料相符. 12)为避免单一分类方法可能导致的不合理结果,本文以自拟的一种综合分类方法,把谱系、进化、分化诸因素均予考虑,得出一个三维图象,以图象 上相对等径的球作为分类依据,得出的结果与分支系统学和数值分类结果基本一致.因此,山麦冬属作为与沿阶草属等阶的分类地位,应予重新考虑. 13)本文最后对这个族的全面修订提出几点建议. 14)此外,本文还描述了沿阶草属4个新种.

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本文研究了富贵草对模拟光斑的光合响应、银杉对光的适应性以及大叶黄杨叶片内部光能利用梯度三个方面的问题。 1)研制了用于林内光环境调查和研究的光量子计组件。 关键词:光量子计,A/D板 2)以亚热带常绿阔叶林下一种常见的灌木富贵草为研究对象,利用气体交换和叶绿素荧光技术研究了其对模拟光斑的光合响应。在同样辐射通量(非光抑制)的情况下,光合诱导过程中光斑可以提高富贵草对光斑的利用能力(光斑诱导的碳同化量可高出对照48%)。叶绿素荧光测量结果表明:1)光斑与光斑之间的暗期发生了qN弛豫过程;2)暗期之后的光期光化学能量转换效率提高。强光光斑簇可以诱导富贵草光抑制的产生,但程度较连续光低。 关键词:模拟光斑, 叶绿素荧光, 光诱导过程 3)用高效液相色谱(HPLC)和77K低温荧光发射光谱技术来研究快速诱导组分发生的时间内光斑所导致NPQ (qN)降低的生理原因。在非光抑制条件下,光斑造成的NPQ (qN)降低的生理原因包括叶黄素循环的变化及LHCIIs聚集态的变化;此外低温荧光数据还显示光斑导致的PSII/PSI荧光产量比率要高于连续光,说明光斑导致植物对于光的利用增加。以上结果说明模拟光斑诱导了富贵草内囊体膜较低水平的能态。 关键词:模拟光斑,叶黄素,聚集态 4)用气体交换等技术测定了部分银杉幼树的生理生态指标,用鱼眼镜头测定了所测叶片的林冠开度(OP)。研究了沿林冠开度梯度的银杉幼树对光的适应性。银杉幼树在林窗边缘表现出较好的适应性,包括高的ISG(综合地上部分茎生长),高的HG(当年生树高生长速率),较高的LMA(单位叶片面积干物质重),较高的Pns(单位叶片干物质水平的净光合速率),高的单位叶片的碳同化速率,较高的截获光的单位叶片的叶面积等等,可以初步确定银杉属于Gap树种:在所测定的范围内(0. 00139%-0. 0109%)TN(土壤总氮量)明显不如OP对银杉幼树生长的影响大;综合的生态可塑性指标必须考虑具体的实验地情况、选取合适的形态学和生理学的因子、并结合多个相似生长环境下的树种来进行考虑。 关键词:林冠开度,生理生态指标,生态可塑性 5)分析了湖南八面山的银杉的某些光合特性,并比较了极郁闭( OP<4%)情况下银杉当年生叶片与大树顶端枝条(OP>30%)当年生叶片之间光合特性上的差异。极郁闭情况下银杉叶片生长出现黄化现象,但银杉幼苗又不耐强光。银杉幼苗一天的光合动态变化表明,银杉最大光合速率在早晨8:00左右,当光照超过光饱和点时,净光合速率迅速下降,其后略有回升,呈不太典型的双峰模式。气孔关闭与净光合速率的下降有密切的关系。早晨8:00到11:00间叶黄素循环运转,对光合系统起到一定保护作用。 关键词: 银杉,色素分析,光合作用 6)采用一种新方法来测量大叶黄杨叶片内部的绝对光能利用效率梯度的曲线。该方法基于光声光谱的深度分析(Depth-Analysis)理论,并结合了光纤微探测器的叶片光梯度测量结果。日本小檗(Berberis thunbergii DC.)叶片的光声光谱扫描显示了深度分析的精确性。实验结果表明:叶片内部利用光能效率最低处在栅栏组织和海棉组织之间(入射光能的0.026%-660nm红光);越靠近叶片的上表皮和下表皮,趋势显示叶片组织利用光能效率有上升的趋势(分别为0.092%,0.036%)。因此,不同叶肉组织绝对光能利用效率是不同的,该实验结果直接证实了Han &Vogelmann 1999b所提出的假设。 关键词: PA深度分析 叶片内部的光梯度 光化学损失 光吸收梯度

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紫茎泽兰(Eupatorium adenophorum Spreng.)作为重要的外来入侵种之一,已严重破坏了入侵地生态系统的结构与功能,同时使当地农林业生产蒙受巨大的损失。因此,明确紫茎泽兰的竞争策略与扩散潜力,对制定合理的控制措施具有重要意义。 土壤氮素增加常常有助于外来种的入侵,那么降氮能否抵制入侵呢?向土壤中添加碳素,增强微生物对氮素的吸收,从而降低土壤中可被植物吸收的氮素是目前常用的降氮方法。为检验这一假说对入侵种紫茎泽兰的适用性,选取入侵种紫茎泽兰和本地种禾本科雀麦(Bromus japonicus)、菊科鱼眼草(Dichrocephala integrifolia),分别单栽或与紫茎泽兰混栽,向各植物组合中添加碳素(按1650克有机质/平方米计)或氮素(按30克氮素/平方米计),并设立对照进行盆栽实验。在碳素添加条件下,紫茎泽兰地上与地下生物量分别比对照降低了71.9% 和 74.9%,而本地种的生物量却没有受到显著影响。同时,碳素添加导致紫茎泽兰对本地种的竞争强度(RII)明显下降。氮素添加则减弱或逆转了上述碳素的作用。因此,向土壤中添加碳素有助于抵抗氮沉降对外来种入侵的促进作用,特别对抵御那些与氮素有亲和力的入侵种更为有效。在不同氮素条件下,紫茎泽兰对本地种竞争中,资源竞争强度均明显大于化感作用。尽管在紫茎泽兰发育早期化感作用较小,但是,碳素添加使紫茎泽兰可利用氮素减少,激发了化感作用在竞争中占有更大的比例,说明资源竞争与化感是相互结合、共同发挥作用的。 去叶作为模拟采食方法之一,至少可以通过两种方式影响植物竞争。一是去叶对目标种生长产生负面影响,二是邻种去叶有利于目标种生长,进而改变种间竞争关系。基于以上假定,对紫茎泽兰与相邻本地种分别单栽、同种合栽和异种混栽,进行去叶处理。结果恰与假定相悖:在整个生长季内,去叶增加目标株生物量的1.0 – 198.9%。对于入侵种而言,当邻居本地种去叶时,紫茎泽兰能完全弥补竞争产生的负面效应,即它与未去叶的单栽紫茎泽兰生长无显著差异;而紫茎泽兰去叶降低了相邻本地种的生长,加剧了原本由于竞争给对本地种带来的负面影响。因此,去叶效应与邻种的存在与否及邻种的类型均有关。在应用生物控制对目标株采食时,特别是在没有造成严重伤害或致死情况下,可以使本来具有竞争优势的入侵种变得更具强势。竞争与去叶之间存在复杂的相互作用,采食带来的间接效应可能比预想的更为复杂。因此,在生物控制措施实施之前,充分地估计生物控制的间接作用至关重要。 为检验反应—扩散模型(reaction–diffusion model)能否正确模拟紫茎泽兰小尺度扩散速率,本研究调查了四川攀枝花山区5个不同的生境的紫茎泽兰群落。对各样地内紫茎泽兰定位和年龄确定,基于克里金插值法做出其入侵格局的等年线图,通过等年线之间的垂直距离即可得到紫茎泽兰扩散速率的经验值。同时,计算内禀增长率和扩散系数,根据模型计算得到扩散速率的预测值。结果表明:紫茎泽兰扩散速率经验值明显小于模型预测值。因此,尽管反应—扩散模型已在大尺度扩散预测方面得到广泛的应用和验证,但在小尺度上,由于没有借助于复杂的生活史模型和分层模型,单凭反应—扩散模型不足以得到准确的预测。另外,在没有遭受干扰的生境中,可以发现紫茎泽兰扩散早期存在明显的时滞期。倘若这种时滞效应在入侵扩散中是频繁发生的,那么在判定物种是否具有入侵性时,很可能由于物种处于时滞期而被误认为非入侵种。 基于紫茎泽兰入侵至中国60年来所收集到的441已知分布记录和23个环境变量,采用GARP模型对其潜在分布范围做出了预测,并通过Kappa和ROC(receiver–operator characteristic)对预测结果进行检验。结果表明紫茎泽兰目前分布以云贵高原为主体,逐渐向四川盆地东部、山东半岛、东南沿海、台湾沿海以及海南岛等地扩散。冷季降水量、年极端低温和年均最高温对分布影响较大。RDA(Redundancy Analysis)分析结果显示温度和降水是限制紫茎泽兰扩散的重要因素。在过去的20年里,紫茎泽兰已经从温度较高、天气波动较小的亚热带气候逐渐向气候温凉、降水减少的高海拔地区扩散。紫茎泽兰可以适应相对较宽的温度和降水梯度,年均温度在10—22 ˚C,年降水量在800—2000 mm区间均有分布。本研究结果为发展早期预警工作、防止紫茎泽兰在中国进一步入侵提供了科学依据。

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三峡库区一些污染严重的工业企业是当地主要的点源污染源,对周围植物群落产生了巨大危害,而植物是生态系统赖以存在的基础,它的生长发育直接影响到生态系统的结构及其正常功能的实现。本研究按照与点源污染源的距离为梯度,通过在三峡库区兴山县白沙河磷化工厂周围布设了32个植物群落固定样地,并以点源污染无法影响到的植物群落为对照,进行样地的野外群落学调查;在每个样地取不同种植物叶片100克左右和样地0~20cm土壤500克,以石灰滤纸法同步进行大气氟化物的取样。样品带回室内应用氟离子选择电极法,测定大气氟化物含量、植物叶片氟的累积量和土壤水溶性氟的含量。同时在野外调查时使用PAM2100叶绿素荧光仪测定植物最大光化学效率即Fv/Fm的值。通过野外调查试验和相关的室内分析,研究了(1):点源污染对三峡库区陆生植物群落组成和物种多样性的影响;(2):点源污染中的主要污染物对植物及土壤环境的影响;(3):不同物种叶片最大光化学效率Fv/Fm对污染胁迫响应的差异。结果如下: 点源污染对植物群落物种丰富度以及Pielou均匀度指数均有不同程度的影响,对于群落结构相对简单的马尾松林和柏木林的不利影响更为显著。相对于污染区来说,对照区中物种重要值的集中程度有所下降。许多物种的重要值在污染区与对照区有明显的变化。马尾松(Pinus massoniana)、檵木(Loropetalum chinense )、铁仔(Myrsine africana)、卷柏(Selaginella tamariscina )等对照区重要值较污染区为高,黄檀(Dalbergia hupeana )、菱叶海桐(Pittosporum truncatum)、君迁子(Diospyros lotus)等污染区的重要值较对照区为高。群落中有些物种比如柏木(Cupressus funebris)的天然更新也受到污染的影响。 污染区土壤pH值大多低于对照区,但是与离污染源距离的相关性不强。污染区有些物种比如马尾松、柏木等叶片中的全氟含量与大气中氟化物的含量和土壤水溶性氟含量明显正相关。但是另外有些物种氟的累积量受点源污染的影响不显著,比如菱叶海桐、翅柃(Eurya alata)等在污染严重的样地内生存状况仍然很好。 在距离点源污染近的样地内,大多数物种的最大光化学效率Fv/Fm的值显著下降。栓皮栎(Quercus variabilis)、马尾松和柏木等的Fv/Fm值与距污染源的距离呈明显的正相关,都是随着离污染源越来越近而逐渐降低。根据污染区相对对照区Fv/Fm值下降幅度的不同,把植物划分为三种类型:对污染敏感型如柏木、铁仔、檵木等,中等敏感型如油桐(Vernicia fordii)、香叶树(Lindera communis)和不敏感型如山胡椒(Lindera glauca)和 蝴蝶花(Iris japonica)等。

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被子植物成熟的种子一般不合有叶绿素,但是莲(Nelumbo nucifera Gaertn.)的胚芽却具有鲜明的绿色,本文较详细地研究了莲胚芽不同于一般被子植物叶组织的色素和光台系统组成,并通过对莲胚芽成熟发育过程中的叶绿素合成和光合系统发育进行分析,探讨了莲胚芽光合特性形成的原因,最后对莲胚芽在黑暗中萌发能发育并建成光合系统的现象进行了研究,主要的结果如下: 1,莲胚芽不仅含有叶绿素和光合系统,而且其色素和光台系统组成均与莲叶以及其它被子植物的叶组织不同。莲胚芽的Chla/b值约为0.8左右,远远低于正常高等植物的Chla/b值(~3):莲胚芽的色素组成中不含有β-胡萝卜素;莲胚芽的光合系统没有电子传递活性,快速荧光动力学测定结果表明莲胚芽只有较高的固定荧光F。没有可变荧光Fv;原位低温荧光光谱检测表明莲胚芽只在679nm处有一个荧光发射主峰,没有正常的PSII和PSI荧光发射峰(683nm、692nm和730nm);部分变性的叶绿素蛋白复合物凝胶电泳分析结果表明莲胚芽叶绿体类囊体膜上只存在LHCII 一种叶绿素蛋白复合物(其中单体和二聚体形式的LHCII均有发现);Western Blots检测结果表明莲胚芽的LHCII组成比较单一,同时确证了莲胚芽不含有PSI的核心和天线蛋白组分。莲胚芽LHCII和莲叶LHCII在SDS-PAGE图谱上迁移距离相同,但是光谱分析表明二者不仅在Chla、Chlb的相对含量上不同,而且在叶绿素分子与蛋白的结合状态上也存在差异,这些差异主要是由一部分Chla分子造成的,Chlb分子在二者中的结合状态则比较~致。 2,对莲胚芽成熟过程中的光合系统发育进行研究,结果表明这个过程可以分为建成期(0-20天)、稳定期(20-30天)和降解期(30—40天)三个阶段。在建成期和稳定期内,莲胚芽外面的包被物可能不是完全遮光的,所以莲胚芽能感受到环境光信号,其叶绿素合成已经光合系统建成集中在此阶段内进行:在莲’胚芽成熟后期,莲胚芽外面的包被组织开始木质化,光信号无法再穿透它们,莲胚芽的光合系统发育进入降解期,叶绿素合成停止,己建成的光合系统开始降解,到莲胚芽成熟时,除LHCIl外,光合系统其余的叶绿素蛋白复合物都被降解了,所以莲胚芽具有不同于一般祓子植物叶组织的色素和光合系统组成。对莲胚芽的成熟发育过程进行遮光处理,结果发现遮光发育的莲胚芽发生明显黄化,这表明莲胚芽的叶绿素合成也离不开光照,在莲总基因组中检测不到编码DPOR的三个基因的同源序列,确证了莲胚芽不具有在黑暗中合成叶绿素的能力。 3,在黑暗中萌发生长的莲胚芽能够在相当长的时间内保持其叶绿素稳定,特别是Chla的含量在暗生长10天以内基本没有变化;原位低温荧光光谱检测表明暗萌发过程中莲苗有PSII和PSI的荧光发射峰形成,暗生长10天左右的莲苗具有比较明显的光合系统荧光发射峰,但是与自然光照下的发育过程相比,暗萌发莲苗的光合系统荧光发射峰出现较慢,而且PSI的荧光发射相对较弱;暗萌发莲苗在转绿以及冻融过程中的原位低温荧光光谱变化表明莲苗在黑暗中建成的光合系统不完善并且不稳定;对莲胚芽、暗萌发莲苗以及莲叶的叶绿体吸收光谱进行比较,结果显示暗萌发莲苗的叶绿体发育阶段介于莲胚芽和莲叶之间;叶绿素蛋白复合物凝胶电泳分离,SDS-PAGE,Western Blots免疫检测、以及叶绿素荧光诱导动力学结果均确证暗萌发莲苗有光合系统的发育,特别是PSI的出现;对暗萌发莲苗的光化学活性进行分析,结果表明暗中建成的PSII和PSI均具有电子传递活性:但是放氧复合物的发育不完全,对莲胚芽暗萌发过程光合系统建成的原因进行分析,推测叶绿素可能起了至关重要的作用,光对于莲胚芽萌发过程中的光合系统发育来说可能并不是必需的。

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记述了采自中国东部福建省武夷山风景区苔藓中的缓步动物11种,包括:日本棘影熊虫Echiniscus japonicus Morikawa,1951中国东部新纪录种;结痂棘影熊虫Echiniscus scabrospinesus Fontoura,1982中国东部新纪录种;华美假棘影熊虫Pseudechiniscus facettalis Petersen,1951中国东部新纪录种;迟缓小斑熊虫Milnesium tardigradum(Doyère,1840);埃卡门大生熊虫Macrobiotus ari

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记述了采自湖北省西部神农架国家森林公园苔藓中的缓步动物12种,包括:日本棘影熊虫Echiniscus japonicus Morikawa,1951;双粒棘影熊虫Echiniscus bigranulatus Richters,1907中国新纪录种;华美假棘影熊虫Pseudechiniscus facettalis Petersen,1951;于猪假棘影熊虫Pseudechiniscus suillus(Ehrenberg,1853);迟缓小斑熊虫Milnesium tardigradum(Doyère,

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<正> 日本国安永统男先生(Norio Yasunaga, 1981)报道在日本长崎五岛一些养殖场饲养的花鲈 Lateolabrax japonicus发生一种粘孢子虫病,引起严重死亡。他从病鱼脑腔里找到这种病原体的孢囊标本,赠给作者两块,以研究它的形态结构和分类问题。通过对标本的详细观察、研究,认为这种粘孢子虫的孢子,形态结构比较特殊,不仅足以作为独立的属,而且是一新科的代表。

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Enzymatic activities and fatty acid methyl esters (FAMEs) in the sediments of two eutrophic lakes in Wuhan city were investigated. The results showed phosphatase and dehydrogenase activities in the lotus zone and plant floating bed zone were significantly lower than those in other sites, and urease activity was the highest where microorganism agents were put in. Fatty acid group compositions indicated the predominance of aerobic bacteria in the surface sediments in shallow lakes. The ratios of FAMEs specific for bacteria and Gram-positive bacteria exibited significant differences between the two lakes. The results of trans to cis indicated that the microorganisms in Lake Yuehu could adapt themselves to environmental stress better. The enzymatic activities and FAMEs showed differences in different sites, indicating that ecological restoration measures and environmental conditions could affect lake sediment to some extent. But the monitoring, work would be done in series to exactly evaluate the effect of the remediation measures.

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The paper studied two estrogenic pollutants, 4-nonylphenol (NP) and 4-tert-octylphenol (OP) in water, suspended particle (SP) and sediments in urban eutrophic lakes. The concentrations of NP ranged from 1.94 to 32.85 mu g/l, 0.876 to 31.13 mu g/l and 3.54 to 32.43 mu g/g dry weight (dw) in water, suspended particle (SP) and sediments, respectively, and that of OP from 0.027 to 1.44 mu g/l, 0.008 to 1.777 mu g/l and 0.058 to 1.245 mu g/g dw in water, suspended particle (SP) and sediments, respectively. An increasing trend in the concentration was noticed in all matrices close to the sewage inlets, which was found to be the major factor affecting the spatial distribution of alkylphenols (APs) in the lakes. Due to restoration of submerged macrophytes, which might accumulate APs, the contaminations of APs in the Little Moon Lake (LML) and the Little Lotus Lake (LLL) were lower than those in the Big, Moon Lake (BML) and the Bier Lotus Lake (BLL). A reasonable correlation of NP and OP was obtained among water, suspended particle and sediment. The possible environmental stress of APs concentration on aquatic organisms in Wuhan urban lakes was also discussed.