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1.
大眼长蝽的外部形态观察(半翅目:长蝽科)   总被引:2,自引:0,他引:2  
本文扼要记述了半翅目长蝽科的大眼长蝽成虫期的外部形态,希图据此获得对大眼长蝽亚科形态学的进一步认识,为长蝽总科的系统发育研究提供资料。文章还兼对该亚科的泡眼长蝽的部分构造作了记载。  相似文献   

2.
缘蝽科的比较形态学研究Ⅲ(异翅亚目:缘蝽总科)   总被引:2,自引:0,他引:2  
李新正 《动物学研究》1996,17(3):195-202
缘蝽科的比较形态学研究 Ⅲ(异翅亚目:缘蝽总科)李新正(中国科学院海洋研究所青岛266071)15棒缘蝽亚科(Pseudophloeinae)(图68—83)棒缘蝽类包括28个属,除VilgaStal为新世界分布,CeraleptusCosta和颗缘...  相似文献   

3.
缘蝽科的比较形态学研究Ⅰ(异翅亚目:缘蝽总科)   总被引:1,自引:0,他引:1  
本研究叙述了缘蝽科的基本特征以及缘蝽科中22个族或亚科级单元的比较形态学特征,特别是外生殖器的特征描述及其图解多为首次报道。认为瘤缘蝽族、喙缘蝽族、竹缘蝽族、沟缘蝽亚科、达缘蝽族、同缘蝽族、特缘蝽族及美洲各族(或亚科)为单系群;梭缘蝽族(包括唯一属梭缘蝽属)的族级地位成立;缘蝽族各属关系复杂;黛缘蝽族是一个复系类群,各属关系复杂,在头部、阳茎和雄虫生殖腔等方面的构造已呈明显差异,此族似不成立;岗缘蝽族应是一单系群,但Plinachtusbasalis似应独立成属并移出岗缘蝽族;曼缘蝽族、昧缘蝽族及鼻缘蝽族[仅1属1种,该属另外1种SinotngusrubromaculusHsiao被移到类缘蝽属中,即Anacanthocorisrubromaculus(Hsiao)(n.comb,新组合)为单属族,它们的系统学地位有待进一步研究;希缘蝽族(或亚科)身体构造很特异,是较原始的缘蝽类群;棒缘蝽亚科亦为较原始的类群,其中棒缘蝽属群各属组成一单系群,证明Stal(1873)将它们成立棒缘蝽族合理;其余棒缘蝽亚科各属虽在某些外部形态上表现出一定的亲缘关系,但属间特征交叉,且与棒缘蝽族有许多共同特征,若归为一族,则造成  相似文献   

4.
作者在研究内蒙古长蝽科标本时,发现长蝽科2个新种:阿拉善叶缘长蝽Emblethis alashanensissp.nov.,巴氏直缘长蝽Ortholomus batui sp.nov.,1个中国新记录属:弯齿长蝽属Raglius Stal,1872,3个中国新记录种:弯齿长蝽Raglius aboacuminatus(Goeze),蒙毛角长蝽Hyalocoris mongolicus Kerzhner,东方林长蝽Drymus orientalis Kerzhner。模式标本保存于内蒙古师范大学昆虫研究所标本馆。  相似文献   

5.
本文对直腹长蝽族(半翅目:长蝽科:地长蝽亚科)的3个种的若虫进行了首次描述,即东方完缝长蝽Bryanellocoris orientalis Hidaka,长刺棘胸长蝽Primierus longispinus Zheng和短头细颈长蝽Vertomannus brevicollum Zheng,其中前二者为该属若虫的首次记述;本文还通过扫描电镜观察对东方完缝长蝽Bryanellocoris orientalis Hidaka身体背面分布的浅色圆点的细微结构进行了揭示。  相似文献   

6.
中国缘蝽属一新种(半翅目:缘蝽科)   总被引:1,自引:0,他引:1  
刘强  郑乐怡 《昆虫学报》1994,37(4):468-469
中国缘蝽属一新种(半翅目:缘蝽科)刘强,郑乐怡(内蒙古师大生物系,呼和浩特010022)(南开大学生物系,天津300071)本文记载了缘蝽科(Coreidae)的缘蝽属(CoreusFabricius,1794)一新种。模式标本存内蒙古师范大学生物系...  相似文献   

7.
研究欧洲和中国的标本后发现,室翅长蝽科Heterogastridae的小异腹长蝽Heterogaster minimusZou&Zheng,1981是地长蝽科Rhyparochromidae的红足点胸长蝽Acompus rufipes(Wolff,1804)的新异名。文中还提供了红足点胸长蝽Acompus rufipes的整体图和雄性生殖器特征图。  相似文献   

8.
狭盲蝽族二新种记述(半翅目:盲蝽科)唐周怀(陕西省动物研究所,陕西省西安市710032)关键词盲蝽科,狭盲蝽族,新种,分类学,中国狭盲蝽族(StenodeminiChina)隶属盲蝽科(Miridae)盲蝽亚科(Mirinae),该族成员适应在禾本科...  相似文献   

9.
本研究叙述了缘蝽科的基本特征以及缘蝽科中22个族或亚和及单元的比较形态学特征,特别是外生殖器的特征描述其图解多为首次报道。认为瘤缘蝽族、喙缘蝽族、竹缘蝽族、沟缘蝽亚科、达缘蝽族、同缘蝽族、特缘蝽族及美洲各族(或亚科)为单系群;梭缘蝽族(包括唯一属梭缘蝽属)的族级地位成立;缘蝽族各属关系复杂;黛缘蝽族是一个复系类群,各属关系复杂,在头部、阳茎和雄虫生殖腔等方面的构造已呈明显差异,此族似不成立;岗缘蝽  相似文献   

10.
中国狄猎蝽族一新属──杨猎蝽属(半翅目:猎蝽科)彩万志(北京农业大学昆虫学系,北京市海淀区100094)狄猎蝽族是真猎蝽亚科的1个小族;连同本文中的新属,目前该族共知10属,均分布于东洋区;Miller(1954)曾对此族进行过比较详细的厘订。这里所...  相似文献   

11.
Disturbances (pulse, press and ramp) constitute a major force influencing, even determining, the structure and functions of ecological components – populations, communities and ecosystems. The capacity to weather a disturbance without loss is defined as resistance, whereas resilience is the capacity to recover from a disturbance after incurring losses, which may be considerable. This article seeks to resolve differences in the ecological definition of resistance and of resilience and to examine the importance of resilience as applied to ecological restoration. In restoration, interventions are designed and implemented with the aim of strengthening the resilience, that is, the capacity to recover, of degraded systems. In response to restorative measures, degraded systems may have both resistance and negative resilience to remain in the degraded state. The key aim of restoration is to overcome the resistance and negative resilience of the degraded state by strengthening positive resilience, the capacity to recover to the intact undegraded state. Restoration may be hindered by a lack of knowledge of acting disturbances (both past and present), of the previous intact condition and of appropriate interventions to implement. Resilience to a disturbance is determined after the disturbance has ceased. Thus, for current ongoing press and ramp disturbances, resilience can be hard to determine.  相似文献   

12.
'Adapt to endure' has become a necessity in agriculture, but the means to do so remain largely undefined. The aim of this literature review is to analyse how the herd contributes to a livestock farming system's capacity to adapt to a changing world and evolve when the future is uncertain. We identify six categories of elements linked to the herd, called 'sources of flexibility', that are used to manage perturbation. The first three are: using the animal's adaptive capacities, using the diversity of species and breeds and combining the diversity of animal products. The last three are: organising the mobility of animals and livestock farmers, juggling the herd numbers and mastering the balance between productivity and herd survival. These sources of flexibility are described in the literature by studying the different ways in which they are used. For example, the 'juggle herd numbers' source is described by volume, categories of animals, type of transfer, such as births, purchases or gifts, and timing of use, especially linked to the timing of the perturbation. Identified studies also compare or rank sources and analyse the connections between them. The flexibility framework (management science) is used for this analysis according to the levels of organisation of a livestock farming system: a strategic level referring to long-term options and to the capacity to modify the system structure, and an operational level referring to adjustment decisions during the productive cycle, the presence or absence of intervention by the livestock farmer, and the time scales involved. We conclude that the decision to use one or another source (in terms of modalities, alternatives, scheduling and combinations) is made according to the production objectives, the structural means, the type/frequency/intensity of perturbations and the context/environment. Consequently, the flexibility of a livestock farming system cannot be assessed in absolute terms. Enhancing flexibility needs management of all elements and scales involved (and not only the herd), and requires diversity to be organised at different scales.  相似文献   

13.
The purpose of this review is to discuss the impact of nanocarriers administered by pulmonary route to treat and to diagnose respiratory and non respiratory diseases. Indeed, during the past 10 years, the removal of chlorofluorocarbon propellants from industrial and household products intended for the pulmonary route has lead to the developments of new alternative products. Amongst these ones, on one hand, a lot of attention has been focused to improve the bioavailability of marketed drugs intended for respiratory diseases and to develop new concepts for pulmonary administration of drugs and, on the other hand, to use the pulmonary route to administer drugs for systemic diseases. This has led to some marketed products through the last decade. Although the introduction of nanotechnology permitted to step over numerous problems and to improve the bioavailability of drugs, there are, however, unresolved delivery problems to be still addressed. These scientific and industrial innovations and challenges are discussed along this review together with an analysis of the current situation concerning the industrial developments.  相似文献   

14.
Farming is the basis of our civilization yet is more damaging to wild nature than any other sector of human activity. Here, we propose that in order to limit its impact into the future, conservation researchers and practitioners need to address several big topics--about the scale of future demand, about which crops and livestock to study, about whether low-yield or high-yield farming has the potential to be least harmful to nature, about the environmental performance of new and existing farming methods, and about the measures needed to enable promising approaches and techniques to deliver on their potential. Tackling these issues requires conservationists to explore the many consequences that decisions about agriculture have beyond the farm, to think broadly and imaginatively about the scale and scope of what is required to halt biodiversity loss, and to be brave enough to test and when necessary support counterintuitive measures.  相似文献   

15.
施永彬  李钧敏  金则新 《生态学报》2012,32(18):5846-5858
生态基因组学是一个整合生态学、分子遗传学和进化基因组学的新兴交叉学科。生态基因组学将基因组学的研究手段和方法引入生态学领域,通过将群体基因组学、转录组学、蛋白质组学等手段与方法将个体、种群及群落、生态系统不同层次的生态学相互作用整合起来,确定在生态学响应及相互作用中具有重要意义的关键的基因和遗传途径,阐明这些基因及遗传途径变异的程度及其生态和进化后果的特征,从基因水平探索有机体响应天然环境(包括生物与非生物的环境因子)的遗传学机制。生态基因组学的研究对象可以分为模式生物与非模式生物两大类。拟南芥、酿酒酵母等模式生物在生态基因组学领域发挥了重要作用。随着越来越多基因组学技术的开发与完善,越来越多的非模式生物生态基因组学的研究将为生态学的发展提供重要的理论与实践依据。生态基因组学最核心的方法包括寻找序列变异、研究基因差异表达和分析基因功能等方法。生态基因组学已广泛渗透到生态学的相关领域中,将会在生物对环境的响应、物种间的相互作用、进化生态学、全球变化生态学、入侵生态学、群落生态学等研究领域发挥更大的作用。  相似文献   

16.
秸秆还田的效果、问题与对策   总被引:1,自引:0,他引:1       下载免费PDF全文
农作物秸秆还田是改善土壤理化性质、增加微生物和酶活性、促进作物增产的有效措施,也是农作物秸秆资源化利用的一种重要方式,但秸秆还田也可能会导致作物出苗率降低、加重作物病虫害发生、引起土壤重金属等有毒有害物质积累等负面影响。目前秸秆以直接还田为主,亦有少量通过堆沤、垫圈等方式间接还田。秸秆在土壤中的腐解速度及还田效果主要取决于秸秆的化学组成特别是C/N、土壤微生物状况、土壤温度及水分含量等。下一步,必须强化秸秆还田方法、快速腐解条件及制剂、对下季作物病害影响及防控、农机农艺配套、缓解全球变化能力等研究,完善相关技术与方法,促进秸秆还田快速推广应用。  相似文献   

17.
Mediterranean environments are characterised by cool wet winters and hot dry summers. While native vegetation in Mediterranean-climatic zones usually comprises a mixture of perennial and annual plants, agricultural development in the Mediterranean-climatic region of Australia has led to the clearing of the perennial vegetation and its replacement with annual crops and pastures. In the Mediterranean environments of southern Australia this has led to secondary (dryland) salinisation. In order to slow land degradation, perennial trees and pasture species are being reintroduced to increase the productivity of the saline areas. The annual crops and pastures that form the backbone of dryland farming systems in the Mediterranean-climatic zone of Australia are grown during the cool wet winter months on incoming rainfall and mature during spring and early summer as temperatures and rates of evaporation rise and rainfall decreases. Thus, crop and pasture growth is usually curtailed by terminal drought. Where available, supplementary irrigation in spring can lead to significant increases in yield and water use efficiency. In order to sustain production of annual crops in Mediterranean environments, both agronomic and genetic options have been employed. An analysis of the yield increases of wheat in Mediterranean-climatic regions shows that there has generally been an increase in the yields over the past decades, albeit at a lower rate than in more temperate regions. Approximately half of this increase can be attributed to agronomic improvements and half to genetic improvements. The agronomic improvements that have been utilised to sustain the increased yields include earlier planting to more closely match crop growth to rainfall distribution, use of fertilisers to increase early growth, minimum tillage to enable earlier planting and increase plant transpiration at the expense of soil evaporation, rotations to reduce weed control and disease incidence, and use of herbicides, insecticides and fungicides to reduce losses from weeds, insects and disease. Genetic improvements include changing the phenological development to better match the rainfall, increased early vigour, deeper rooting, osmotic adjustment, increased transpiration efficiency and improved assimilate storage and remobilisation. Mediterranean environments that are subjected annually to terminal drought can be both environmentally and economically sustainable, but to maximise plant water use efficiency while maintaining crop productivity requires an understanding of the interaction between genotypes, environment and management.  相似文献   

18.
The increasing availability of large metabolomics datasets enhances the need for computational methodologies that can organize the data in a way that can lead to the inference of meaningful relationships. Knowledge of the metabolic state of a cell and how it responds to various stimuli and extracellular conditions can offer significant insight in the regulatory functions and how to manipulate them. Constraint based methods, such as Flux Balance Analysis (FBA) and Thermodynamics-based flux analysis (TFA), are commonly used to estimate the flow of metabolites through genome-wide metabolic networks, making it possible to identify the ranges of flux values that are consistent with the studied physiological and thermodynamic conditions. However, unless key intracellular fluxes and metabolite concentrations are known, constraint-based models lead to underdetermined problem formulations. This lack of information propagates as uncertainty in the estimation of fluxes and basic reaction properties such as the determination of reaction directionalities. Therefore, knowledge of which metabolites, if measured, would contribute the most to reducing this uncertainty can significantly improve our ability to define the internal state of the cell. In the present work we combine constraint based modeling, Design of Experiments (DoE) and Global Sensitivity Analysis (GSA) into the Thermodynamics-based Metabolite Sensitivity Analysis (TMSA) method. TMSA ranks metabolites comprising a metabolic network based on their ability to constrain the gamut of possible solutions to a limited, thermodynamically consistent set of internal states. TMSA is modular and can be applied to a single reaction, a metabolic pathway or an entire metabolic network. This is, to our knowledge, the first attempt to use metabolic modeling in order to provide a significance ranking of metabolites to guide experimental measurements.  相似文献   

19.
动物生物学是揭示动物生命活动规律的科学。作为生命科学专业本科学生最早接触到的主干课程之一,动物生物学的教学对于学生了解生物学的基本概念和基础知识、构建生命科学的知识体系和思维方式、培养和巩固专业兴趣十分重要。系统回顾和总结了动物生物学研究对生命学科发展的贡献,阐明了动物生物学教学对生命科学人才培养与学科建设的作用,引起广大的生物学教学工作者和管理者对动物生物学教学的重视,促进传统重要基础课程的建设与发展。  相似文献   

20.
Guidance molecules present in both axonal and dendritic growth cones mediate neuronal responses to extracellular cues thereby ensuring correct neurite pathfinding and development of the nervous system. Little is known though about the mechanisms employed by neurons to deliver these receptors, specifically and efficiently, to the extending growth cone. A deeper understanding of this process is crucial if guidance receptors are to be manipulated to promote nervous system repair. Studies in other polarised cells, notably epithelial, have elucidated fundamental routes to the intracellular segregation of molecules mediated by endosomal pathways. Due to their extreme complexity and specialisation, neurons appear to have built upon these generic systems to evolve sophisticated trafficking networks. A striking feature is the axon initial segment which acts like a valve to tightly regulate the flux of molecules both entering and leaving the axon. Once in the growth cone, further controls operate to enhance the retention or rejection, as appropriate, of membrane receptors. We discuss the current state of knowledge regarding the intracellular trafficking of axon guidance receptors and how this relates to their developmental roles. We highlight the various facets still to be properly elucidated and by building on existing data regarding neuronal polarity and intracellular sorting mechanisms suggest ways to fill these gaps.  相似文献   

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