气相色谱在昆虫分类上的研究与应用

<正> 随着新技术、新方法的研究与应用,使昆虫的分类逐步向着更准确地反映昆虫种类特征和系统发生关系的高水平、高层次发展,也使一些疑难的近缘种类的鉴别成为可能。分类学家们把遗传学、生理学、生化学,以及计算机等方面的最新成果应用于昆虫分类学中,如用染色体、同功酶及昆虫体内稳定化合物等因子作为分类     

中国昆虫染色体的研究现状

<正> 昆虫染色体的研究,对昆虫分类学如分类系统的建立、近缘种的区分乃至种下分类;对遗传学包括分子遗传学及对害虫的遗传防治等;对昆虫的种类演替规律、种间种内进化甚至对害虫产生抗药性的机理等自然奥秘的揭示具有重要意义。中国自从李汝琪教授于1930年首     

植物的染色体组和组型分析

植物染色体组的测定和组型分析,对于研究植物的系统演化,物种之间的亲缘关系,某些作物的起源,远缘杂种及染色体工程中的细胞学鉴定等都有重要意义。是细胞遗传学、细胞形态学和细胞分类学研究中的基本方法之一。     

我国直翅目昆虫细胞分类学研究现状

从研究材料、研究方法、染色体研究在昆虫分类上的应用 3个方面对我国昆虫尤其是直翅目昆虫的细胞分类学研究情况作了简要的概述 ,并着重论述了直翅目昆虫的核型及带型的研究现状 ,同时对我国直翅目昆虫分类学的发展前景进行了展望     

摇蚊马氏管和直肠多线染色体的初步研究

从发育观点观察了摇蚊成蚊马氏管、直肠细胞中的多线染色体,特别是第Ⅳ染色体自幼虫至成蚊的动态变化过程。结果表明:染色体在个体发育中的变化是有规津的,并与细胞的分化和活动密切相关的;染色体泡和多线分化反映着细胞的结构与功能。本文特别强调了研究双翅目昆虫消化道后部器官在发生遗传学上的重要意义。     

波斯锐缘蜱的核型与细胞分类研究(蜱螨亚纲:软蜱科)

细胞分类学(cytotaxonomy)是细胞遗传学的一个分支学科,主要根据染色体的特征,细胞学和分类学的方法相结合,研究生物的自然分类。它为古老的经典分类学开拓了新领域。细胞分类学在许多动物中的应用已越来越广泛。在蜱螨中,早在60年代初,苏联学者(1962a)研究了软蜱的核型与分类的关系。Oliver(1977)据现有蜱螨染色体资料推论:如果将来寄螨目(Parasitiformes)4个亚目的蜱螨都是单着丝粒(monokinetic)染色体,螨目(Acariformes)3个亚目的螨类都是全着丝粒(holokinetic)染色体,那末蜱螨进化二源论将更加可信。我们比较过草原革蜱与森林革蜱的核型,有7个共同点,说明该两种蜱有较近的亲缘关系(周洪福等,1987)。     

蝗总科染色体研究及科级综合比较（直翅目）

对国际范围内蝗总科染色体研究简史及细胞分类学研究概况进行了回顾,并对我国蝗总科细胞分类学研究进展作了简要介绍。在此基础上,本文根据染色体数目、形态、染色体分组型式、性染色体位置、Ｃ带结构特征及异染色质总含量值等多方面特征对蝗总科８个科细胞分类学相互关系进行了综合比较。结果表明：癞蝗科染色体特点明显,进化位置独特;锥头蝗科与瘤锥蝗科相互近缘;斑腿蝗科与斑翅蝗科较为相近,网翅蝗科与槌角蝗科在染色体多项     

2种辉蝽的精巢和染色体研究(半翅目:蝽科)

通过探讨中国蝽科Pentatomidae辉蝽属Carbula的红角辉蝽Carbula crassiventris(Dallas,1849)和北方辉蝽C.putoni(Jakovlev,1876)的精巢形态和染色体的核型及减数分裂行为,为蝽科昆虫的细胞分类学提供新资料。采用显微形态解剖法和染色体制片法对其精巢和染色体进行观察。结果表明:2种精巢的位置、外被颜色、形状及精巢叶的数目都一致;染色体组成均为2n(♂)=14(12A+XY),具有X-Y性别决定机制。在减数分裂过程中,常染色体前减数分裂,性染色体后减数分裂且无交叉;在中期-Ⅱ,常染色体排列成环状而性染色体在环中央形成假二价体。但是,2个物种在弥散期常染色体的去固缩程度,终变期常染色体双交叉的个数及中期-Ⅰ常染色体和性染色体的排列方式都各不相同。本文证实了蝽科昆虫的减数分裂行为在不同属间、种间可不相同,而且具有一定的属、种间特异性;同时为精巢在蝽类昆虫分类中的作用提供新的资料。     

蜉蝣目昆虫染色体制备方法探讨

本文对蜉蝣目昆虫染色体制备方法进行了探讨。以蜉蝣稚虫为材料,经秋水仙素水溶液体外培养,采用显微操作技术,结合空气干燥法,可以获得形态良好、分散适中、着色清晰的生殖细胞染色体,为蜉蝣目昆虫细胞遗传学研究提供了一种简便有效的方法。     

植物细胞分裂和染色体形态

植物染色体形态大致关系到三个方面:细胞遗传学、细胞分类学和染色体各种鉴定。历来染色体的研究多结合遗传性状的传递和变异,例如染色体结构的变化(缺失、重复、倒位和易位)与数目的变化往往就反映出不同的遗传性。另一方面,应用染色体变化,探讨植物的演化与分类,也已是染色体形态的研究的一个重要部分,但是这一领域在我国,目前尚处于空白状态。至于染色体的鉴定应用在组织     

中国慈姑属系统发育的研究

本文研究了中国慈姑属植物间的系统发育关系。选取了12个与该属系统发育有较重要关系的特征,将8个已知分类群与外类群刺果泽泻属进行了比较。应用数量分支分析的Farris-Wagner方法,建立了中国慈姑属系统发育分支图。讨论了各分类群间的系统发育关系、该属起源和数量分支分析方法等问题。     

Phenetic and phylogenetic studies based on measurements of Plantago ser. Brasilienses

Numerical taxonomic methods for a programmable pocket calculator are proposed. Operational taxonomic units (OTU's) may be either accepted taxa or single specimens, or a mixture of both. All types of characters are employable. A calculated or estimated common standard deviation and the mean (or reading) define the normal distribution curve for each measurement variable. Similarity between two OTU's is calculated as the overlapping area below their distribution curves. Ninety specimens of Plantago ser. Brasilienses are used as examples. The clusters are finally grouped using both phenetic and several cladistic methods. Results from phylogenetic sys–tematics cannot be used directly in taxonomy because the basic principles are discordant with those in the botanical code.     

横断山区六种八居群鼠尾草属植物的核型分析

鼠尾草属(Salvia)是唇形科(Lamiaceae)最大的属,属下多种为民间常用草药,亦有供观赏的种类。为探究横断山区物种在细胞学水平的进化方式,讨论形态分类学与分子系统学之间的分类关系,该研究通过广泛收集染色体文献资料,采用植物常规压片法对采集自横断山地区6种8居群鼠尾草属植物进行核型分析,并构建了中国地区分布的鼠尾草属植物叶绿体系统发育树。统计结果表明:(1)全世界范围内报道了约23%的鼠尾草属植物染色体数据,其中分布在中国地区的鼠尾草属植物染色体报道率为32.10%,分布在横断山地区的鼠尾草属植物报道率为40.54%,(2)鼠尾草属植物染色体基数以x=8和x=11为主,分布在中国地区的鼠尾草属植物染色体基数均为x=8。实验结果表明:(1)西藏鼠尾草(S. wardii)核型数据为首次报道。(2)雪山鼠尾草(S. evansiana)首次在云南德钦地区发现二倍体居群。将细胞学数据结合叶绿体进化树开展染色体进化关联分析,论证多倍化可能不是鼠尾草属物种适应高海拔环境的主要机制,表明多倍体不是该属物种形成的主要进化途径而是以二倍体水平为主,推测染色体组的加倍可能是物种在形态学与分子系统学上分类关系不一致的原因之一。该研究丰富了横断山区鼠尾草属植物的染色体核型数据,结合区域分子系统树探讨染色体特征的进化关系,为今后深入研究该属物种的核型进化做出了探索,为开展祖先物种染色体基数推演分析补充了基础数据。     

原尾纲重新分群的特征分析(六足总纲)

1996年第20届国际昆虫学大会（意大利佛罗伦萨）上,尹文英根据多年研究的新发现提出了原尾纲Protura分为3目10科的新建议,仅刊登在该次会议的论文摘要中,至今尚未能详细阐述重新分群的重要特征和分析。本文拟就原尾纲不同类群的成虫和幼虫主要特征进行分析和比较,结果证明原尾纲分为3目（Yuan目、华Yuan目和古Yuan目）10科,更符合原尾虫客观发展的自然规律。     

Cladistic Analysis of Human Evolution: Some Points on Character Selection

Cladistic analysis strongly depends on accurate character choice. Usually, characters include morphology or molecules, but other sources of evidence are also employed. These include stratigraphic ages of taxa and behavioural data. The inclusion of time is a controversial issue, which has no Darwinian basis. However, the cladistic treatment of stratigraphic age has the potential to resolve problematic phylogenies. Here, it is proposed that the use of stratigraphic data in phylogenetic inference should be seen as a temporary shortcut, to resolve complex phylogenies in the wait for new character and taxonomic samplings, because phylogenetic hypotheses should be based on biological evidence only. Archaeologists working on toolmaking can provide behavioural data in human prehistory. In fact, while a tool itself is not biological evidence, the movements of hands and arms needed to prepare it are biological evidence and can be compared and scored for cladistic analysis. Such an approach has been formalized in studies on functional morphology of some vertebrates. The taxonomic data set to be used in cladistic analysis should include as many taxa as possible, and also very incomplete specimens should be used. In many cases, incomplete specimens had the potential to resolve complex phylogenies by adding new character combinations that cannot be scored in molecule-based phylogenetic studies.     

PHYLOGENETIC RETICULATIONS AND CLADISTICS: DISCUSSION OF METHODOLOGICAL CONCEPTS

Abstract— Some problems associated with a cladistic treatment of complex taxa (hybrids and holobionts) are reviewed and discussed. The authors recommend aplication of standard cladistic analysis to all taxa, regardless of their supposed mode of origin. The position of a complex taxon depends entirely on the set of characters it shares with other taxa. This approach is preferable, because there are no means to distinguish deductively between various kinds of character conflicts (the recognition of one character as incongruous with others says nothing about its evolutionary origin). All other approaches have been proposed so as to reflect the topology of reticulate phylogenetic trees, but, at the same time, they require prior knowledge of the complex nature of a taxon.     

核型分析在细胞分类学中的应用

细胞学的核型分析资料作为分类学的证据,结合形态学、解剖学、胚胎学和遗传学等方面的证据,在解决分类上的疑难问题,起过不少的作用,而且是建立生物学种和建立新的自然分类系统所必不可少的资料。     

How much can cladistics tell us about early hominid relationships?

Although cladistic analysis has been used to compare hypotheses of relationships among early hominids, the outcomes of different studies have depended entirely on the assumptions made by different investigators. Problems include the close genetic relationship of early hominid taxa, small fossil sample sizes, possible correlations among characters, and a lack of understanding about the evolutionary factors affecting characters. This study investigates the interaction of some of these problems affecting early hominid phylogenetics. Monte Carlo simulations of character state evolution in closely related taxa demonstrate that the sample sizes and close genetic relationships of early hominids do not permit cladistic analyses to obtain unequivocal results. Even with unrealistically good assumptions about the evolutionary dynamics affecting characters, the probability of the most parsimonious hypothesis being true is unacceptably small. In the face of these problems, even phylogenetic statements that are supported by a strong consensus of cladistic studies may nevertheless be in error, and such errors are likely to confound the placement of new specimens and taxa. Advancement in our knowledge of hominid phylogeny can depend only on a fuller understanding of the natural history and evolutionary dynamics of traits.     

PHYLOGENETIC SELECTION OF A RESOURCE: A NEW USE FOR CLADISTICS

A phylogenetic model for the selection of commercial resources using the cladistic method is proposed. The group selected as an example was the marine agarophyte red algal genus Gracilaria Greville. We suggest the use of the cladistic principle of evolutionary transformational series in order to test the quality of agars instead of the assay‐herror traditional method that consumes time and budget. If we asume that the “good quality of agar” in extant taxa is a sinapomorphic character (but not a reliable taxonomic one), then taxa included in the same monophiletic clade in which the species with “good quality of agar” are, has a high evolutionary posibility to share that character. In order to do this we have to incorporate to the set of available specific characters, those of the taxa actually used as a agar source but not present in the area under scope. A complete set of the basic cladistic data required for run the most popular program currently in use (PAUP) are provided. We applied the model to the Mexican Atlantic species and found that, using Gracilaria chilensis and G. cornea as “indicator taxa,” and found Mexican populations of G. crassissima, G. caudata, G. cervicornis and Gracilariopsis lemaneiformis are candidates for a study of yield and agar properties.