变豆菜属15种植物的果实微形态特征及其分类学意义

采用扫描电镜对来自北美和东亚的变豆菜属植物(美国7个种,中国8个种)的果实表面微形态进行观察,结合前人对伞形科其他类群果实微形态特征的研究及近年来分子系统学证据,对变豆菜属的种间分类进行研究。结果显示,变豆菜属植物果实的形态大小、皮刺弯曲程度和果柄蜡质纹饰丰富多样。研究表明变豆菜属是一个自然类群,果实表面钩刺结构有利于该属植物的传播及扩散,果实微形态特征具有分类学价值,可作为种间分类的依据。根据变豆菜属果实表面微形态特征,编制了该属植物分种检索表。     

Chemical defences in leaf beetles and their larvae: The ecological, evolutionary and taxonomic significance

The chemical defences of the Chrysomelinae are reviewed. Defensive glandular secretions have evolved independently in larvae and adults, and faster than the morphology of the glands. Both characters are used in a phylogenetic study of the Chrysomelini, disclosing suprageneric affinities. First, a close relationship between the Chrysomelina and Phratora is proposed. Secondly, Leptinotarsa and Gonioctena are probably more closely related to the Chrysolinina than to the Chrysomelina and Phratora. The qualitative and quantitative composition of larval and adult secretions sometimes differs between geographically isolated populations of the same species, which are therefore probably genetically distinct. The host plant shows an influence which explains discrepancies between the current classification and the chemical nature of the secretions. Some beetles sequester secondary plant metabolites or use them as precursors for their own defences. The original biosynthetic pathway has been lost in these species. Other factors which could affect the chemical diversity of the secretions are discussed: random events such as neutral mutations and genetic drift, conditioning or adaptation of predators to specific defensive mixtures, and the diversity of potential predators. The latter could help to explain the divergence in the chemical nature of the larval and adult secretions. The volatile irritants produced by the larvae are well suited to repel small arthropods, such as ants, whereas poisons associated with aposematic coloration in the adults could be directed against small vertebrates, such as birds.     

Chemical constituents of the roots of Scorzonera divaricata and their chemotaxonomic significance

The phytochemical study of the roots of Scorzonera divaricata Turcz led to the isolation of 27 compounds, including eight sterols (1–8), one lignan (9), two cumarins (10, 11), five phenylpropanoids (12–16), six benzene derivatives (17–22), methyl-β-D-fructofuranoside (23), monolinolein (24), and three aliphatic acids (25–27). The structures of isolated compounds were identified using NMR and ESI-MS spectroscopic methods and comparing them with those previously reported. Except for β-daucosterol (8), scopoletin (10) and caffeic acid (16) from S. divaricata, this is the first report of the other 24 compounds from S. divaricata. Among them, eleven compounds (2–6, 11, 17, 19, 20, 23, 25) were reported from genus Scorzonera for first time, suggesting that they could be used to distinguish S. divaricata from the other species of Scorzonera. Furthermore, the chemotaxonomic significance of isolated compounds from S. divaricata has also been discussed.     

Chemical constituents from the whole herbs of Peperomia tetraphylla and their chemotaxonomic significance

Our studies report the isolation of seventeen compounds (1–17), which include three phenolic acids (12–14), seven flavonoids (3, 6, 8, 11, 15–17), four secolignans (1, 2, 5 and 9), one tetrahydrofuran lignin (10) and two alkaloids (4 and 7). These compounds have been obtained from the Peperomia tetraphylla using chromatographic methods. Their structures were confirmed based on spectroscopic methods. Among them, five compounds (4, 7, 8, 11 and 15) were found in the family, four compounds (3 and 12–14) were firstly reported from genus Peperomia, and four compounds (6, 9, 16 and 17) were firstly obtained from this species. Furthermore, the chemotaxonomic significance of these ingredients from the whole plants of P. tetraphylla has been discussed in detail.     

Chemical constituents from the fresh flower buds of Musa nana and their chemotaxonomic significance

Phytochemical study on the fresh flower of Musa nana Lour. provided seventeen known compounds including two alkaloids, 3-(hydroxyacetyl)-indole (1), bi-indol-3-yl (2), two terpenoids, 5-[(1R)-1-hydroxy-2,6,6-trimethyl-4-oxo-2-cyclohexen-1-yl]-3-methyl-, (2Z, 4E) −2, 4-pentadienoic acid (Valdes), 5, 6(S), 7, 7a(R)-tetrahydro-6-hydroxy-4,4-dimethyl-2(4H)-benzofuranone (4), seven phenols (5–11), three phenylphenalenones, 2-hydroxy-4-(4-methoxyphenyl)-1H-phenalen-1-one (12), 2-methoxy-9-phenyl-1H-phenalen-1-one (13), 2-methoxy-9-(4-methoxyphenyl)-1H-phenalen-1-one (14), and three lipids (15–17). In the present study, all the compounds were isolated for the first time from the species M. nana. Ten compounds including 1-8 and 15-16 have never been previously encountered in the Musaceae family. Furthermore, the chemotaxonomic significance of these isolates was also discussed.     

Chemical constituents from the pericarps of Zanthoxylum bungeanum and their chemotaxonomic significance

The phytochemical study of the pericarps of Zanthoxylum bungeanum Maxim under the guidance of bioactivity led to the isolation of 18 compounds, including a new isobutylhydroxyamide (1) and 17 known compounds, i.e. six alkylamides (2–7), five coumarins (8–12), one benzene derivative (13), three flavonoids (14–16), and two sterols (17–18). Their structures were elucidated based on extensive spectroscopic methods (HRESIMS, 1D and 2D NMR experiments) and by comparison with literature data. New compound (1) and known compound (2) are cis-trans isomeric isobutylhydroxyamides. Among them, compounds 9, 10, and 12 were isolated for the first time from Z. bungeanum, compound 11 was firstly recovered from the genus Zanthoxylum, and compound 14 was reported for the first time from the Rutaceae family. The chemotaxonomic significance of isolated compounds from Z. bungeanum is discussed.     

Septal micropores in Zygozyma and their taxonomic significance

Septal micropores or plasmadesmal canals have been observed in two species of the lipomycetaceous genus Zygozyma. The presence of these canals is considered as further evidence for the connexion between the Lipomycetaceae and the Dipodascaceae. The genus Zygozyma has been emended.     

南五味子属（五味子科）的种子形态及其分类学意义

在光学显微镜和扫描电镜下对南五味子属Kadsura 11种植物36个样品的种子宏观形态及种皮微 形态特征进行了研究。结果表明其种子形状为肾形、椭球形、心形或肾状扁球形。在扫描电镜下种子表 面特征有种间差异,其纹饰可分为3种类型,即近平滑型、负网纹型和网纹型。短梗南五味子K． borneensis和披针叶南五味子K．lanceolata为近平滑型,其种子表面近平滑;黑老虎K．coccinea和柄果 南五味子K．verrucosa 为负网纹型,其种子表面具负网纹,网眼凸起,网脊凹陷;异形南五味子K．hetero- clita、毛南五味子K．induta、南五味子K．japonica、冷饭藤K．oblongifloia、狭叶南五味子K. angustifolia、 南洋南五味子K．scandens 和大叶南五味子K．marmorata为网纹型,其种子表面具网纹,网眼凹陷,网脊 凸起,此类型在南五味子属中最为普遍。种皮微形态特征在种内相当稳定,在一些种的划分上具有较重 要的意义。南五味子属种皮微形态特征的研究结果支持将多子南五味子K．polysperma和凤庆南五味子 K. interior 归并入异形南五味子以及将长梗南五味子K．longipedunculata归并入南五味子的分类学处理。本文还对南五味子属植物种皮微形态的各种类型的演化趋势作了讨论。     

Crystals and their taxonomic significance in some Verbenaceae

MATHEW, L. & SHAH, G. L., 1984. Crystals and their taxonomic significance in some Verbenaceae. The morphology, plant distribution and chemical composition of crystals in 35 tropical species in the family Verbenaceae have been investigated using light microscopy, SEM and an energy dispersive X-ray analyser.
Crystals may be solitary, aggregated or as conglomerates and crystal sand. Eleven kinds of solitary crystals and five aggregate or conglomerate forms have been observed. Their occurrence varies from species to species and sometimes from organ to organ in the same plant, suggesting that there might be taxonomic significance of crystal form and distribution.
Most of the crystals are compounds of a range of elements, silicon, calcium, potassium, iron, magnesium, aluminium, sulphur sodium and titanium in varying proportions. Calcium is the major component of solitary acicular crystals and silicon of other kinds of crystals.     

Spatial analysis of taxonomic and genetic patterns and their potential for understanding evolutionary histories

Aim The aim of this research is to develop and investigate methods for the spatial analysis of diversity based on genetic and taxonomic units of difference. We use monophyletic groups of species to assess the potential for these diversity indices to elucidate the geographical components of macro‐scaled evolutionary processes. Location The range occupied by Pultenaea species in temperate and sub‐tropical eastern Australia, extending from western South Australia (133° E–32° S) to Tasmania (146° E–43° S) to coastal central Queensland (148° E–20° S). Methods We applied a series of both spatially explicit and spatially implicit analyses to explore the nature of diversity patterns in the genus Pultenaea, Fabaceae. We first analysed the eastern species as a whole and then the phylogenetic groups within them. We delineated patterns of endemism and biotic (taxon) regions that have been traditionally circumscribed in biogeographical studies of taxa. Centres of endemism were calculated using corrected weighted endemism at a range of spatial scales. Biotic regions were defined by comparing the similarity of species assemblages of grid cells using the Jaccard index and clustering similar cells using hierarchical clustering. On the basis that genetically coherent areas were likely to be more evolutionary informative than species patterns, genetic indices of similarity and difference were derived. A matrix of similarity distances between taxa was generated based on the number of shared informative characters of two sections of trnL‐F and ndhF chloroplast nuclear regions. To identify genetically similar areas, we clustered cells using the mean genetic similarities of the species contained within each pair of cells. Measures of the mean genetic similarity of species in areas were delineated using a geographically local multi‐scalar approach. Resultant patterns of genetic diversity are interpreted in relation to theories of the evolutionary relationships between species and species groups. Results Centres of Pultenaea endemism were defined, those of clades 1 congruent with the spatially separated centres of clades 2 and 3. The taxonomic classification analysis defined cells with shared groups of species, which in some cases clustered when plotted in geographic space, defining biotic regions. In some instances the distribution of biotic regions was congruent with centres of endemism, however larger scale groupings were also apparent. In clade 1 one set of species was replaced by another along the extent of the range, with some connectivity between some geographically disjunct regions due to the presence of widespread species. In the combined analysis of clade 2 and 3 species the major biotic (taxonomic) groups with geographic coherence were defined by species in the respective clades, representing the geographic separation of these clades. However distinctive biotic regions within these main groupings of clades 2 and 3 were also apparent. Clustering cells using the mean genetic similarities of the species contained within each pair of cells indicated that some of the taxonomically defined biotic boundaries were the result of changes in composition of closely related species. This was most apparent in clades 1 and 2 where most cells were highly genetically similar. In clade 3 genetically distinct groups remained and were in part defined by sister taxa with disjunct distributions. Gradients in mean genetic similarity became more apparent from small to larger scales of analysis. At larger scales of analysis, regions of different levels of genetic diversity were delineated. Regions with highest diversity levels (lowest level of similarity) often represented regions where the ranges of phylogenetically distinctive species intergraded. Main conclusions The combined analysis of diversity, phylogeny and geography has potential to reveal macro‐scaled evolutionary patterns from which evolutionary processes may be inferred. The spatial genetic diversity indices developed in this study contribute new methods for identifying coherent evolutionary units in the landscape, which overcome some of the limitations of using taxonomic data, and from which the role of geography in evolutionary processes can be tested. We also conclude that a multiple‐index approach to diversity pattern analysis is useful, especially where patterns may be the result of a long history of different environmental changes and related evolutionary events. The analysis contributes to the knowledge of large‐scale diversity patterns of Pultenaea which has relevance for the assessment of the conservation status of the genus.     

Embryological studies in some grasses and their taxonomic significance

BHANWRA, R. K., KAUR, N., KAUR, N. & GARG, A., 1991. Embryological studies in some grasses and their taxonomic significance. The species investigated are Lolium multiftorum Lam (tribe Poeae), Rostraria cristata (Linn.) Tzevlev (tribe Aveneae), Cenchrus setigerus Vahl, Digitaria abludens (Roem. et Schult.) Veld, and D. ciliaris (Retz.) Koel (tribe Paniceae). Apart from the number of microsporocytes in a median longitudinal section of each anther lobe, microsporogenesis and male gametophyte development are similar. However, members of subfamilies Pooideae and Panicoideae show marked differences in structure of the ovary, ovule and post-fertilization development. Lolium multiftorum and R. cristata vary in the structure of the dorsal ovary wall, degree of curvature in the megagemetophyte in relation to the longtitudinal axis of the ovule, and structure of the pericarp. Cenchrus setigerus is an aposporic apomict and differs markedly from species of Digitaria in this respect, in the extent of development of the inner integument and in the constitution of the dorsal ovary wall. The two species of Digitaria show minor embryological differences.     

Chemical constituents from Valeriana officinalis L. var. Iatifolia Miq. and their chemotaxonomic significance

Twenty-one compounds, including four monoterpenoids (1–4) (two new natural products, 1 and 2), four sesquiterpenes (5–8), two iridoids (9 and 10), four steroids (11–14), five phenolic compounds (15–19), and two alkaloids (20 and 21), were isolated from the roots of Valeriana officinalis L. var. Iatifolia Miq. Their chemical structures were established by spectroscopic methods and further confirmed by comparison with published data in the literature. Among them, eight compounds (1, 2, 6–8, 13, 18, and 21) are being reported from the family Valerianaceae for the first time, and compounds 9–12 were obtained from V. officinalis for the first time. The chemotaxonomic significance of the isolated compounds is discussed.     

Chromosome numbers and their taxonomic implications in the genusPoa of Japan

As part of the work leading to a taxonomic revision ofPoa of Japan, chromosome numbers of nearly all indigenous species of JapanesePoa, together with those of some putative interspecific hybrids, were examined. The following chromosome numbers were found:Poa annua, 2n=28;P. crassinervis, 2m=28;P. acroleuca, 2n=28;P. hisauchii, 2n=28;P. nipponica, 2n=28;P. crassinervis, 2n=28;P. acroleuca, 2n=35;P. tuberifera, 2n=28;P. fauriei, 2n=28;P. radula, 2n=42;P. hakusanensis, 2n=70;P. hayachinensis, 2n=42;P. malacantha var.shinanoana, 2n=63≈98;P. yatsugatakensis, 2n=ca. 71≈74, 77;P. sachalinensis, 2n=63, ca. 64, ca. 74;P. matsumurae, 2n=28;P. ogamontana, 2n=42;P. sphondylodes, 2n=28;P. viridula, 2n=42, 49, 56;P. nemoralis, 2n=70;P. glauca, 2n=42, 49, 56;P. eminens, 2n=42. It became clear that information obtained from chromosome counts is quite helpful in clarifying species boundaries in several species aggregates, such as thePoa acroleuca-hisauchii-nipponica aggregate. Results of the examination of morphological features of the voucher specimens in various species aggregates with taxonomic difficulties were reported, and the needs of some amendments for the species delimitation appearing in current floristic manuals were pointed out. A summary of chromosome counts so far made for JapanesePoa was tabulated. ThePoa flora of Japan characteristically lacked diploid plants.     

携带污染物降解基因的可移动基因元件及其介导的生物修复

可移动基因元件(mobile genetic elements,MGEs)在环境微生物群落中的水平转移是细菌基因组进化和适应特定环境压力的重要机制.在污染土壤和水体中接种携带具有降解基因MGEs的菌株后,随着MGEs的水平基因转移,可使降解基因转移至具有竞争性的土著微生物中并在其中表达,从而不必考虑供体菌在环境中是否能够长期存活.这种由可移动降解基因元件水平转移介导的生物修复为探索新的生物修复途径提供了可行性.本文重点综述了环境样品中携带降解基因MGEs的多样性及其在促进污染物降解过程中的重要作用,介绍了从环境样品中分离代谢MGEs的方法,并列举了在污染土壤、活性污泥、其他生物反应器等生态系统中MGEs水平转移的几个实例.     

Trichomes and stomata,and their taxonomic significance in theUrticales

Structure and ontogeny of stomata and trichomes have been studied in 23 species and 3 varieties of theUrticales. Stomata are anomocytic, more rarely paracytic; anisocytic and sometimes helicocytic and transitorial types are found inUrticaceae andDorstenia, rarely inArtocarpus. The ontogeny of anomocytic and actinocytic stomata is perigenous, of paracytic either mesogenous or perigenous, of anisocytic either mesogenous or mesoperigenous, and of helicocytic and transitional types mesogenous. Among trichomes eglandular unicellular (wide spread), bicellular or uniseriate filiform (Cannabis); glandular capitate with uni- or bicellular (Moraceae, Ulmaceae, Cannabaceae), uniseriate filiform (Ulmaceae) or multiseriate stalk (Cannabis); sunken glands (Artocarpus); uniseriate glandular with uniseriate stalk (Celtis), and stinging emergences (Urticaceae) have been observed. It is concluded that theUrticales represent a natural order with four families:Ulmaceae, Moraceae, Urticaceae andCannabaceae which are distinct but interrelated with each other.     

The flavonoids in Epimedium L. and their taxonomic significance

In this paper, the distribution and quantity of flavonol glycosides with isoprenyl in the eighth position (A kind) or without isoprenyl (B kind) in Epimedium were analyzed by HPLC. The following results of taxonomic significance were obtained: 1 )According to the chemical characteristics, Epimedium could be divided into three groups: A group, mainly with A kind of flavonol glycosides; B group, mainly with B kind of fiavonol glycosides; AB group, sharing the two kinds. Eight taxa (species or subspecies) in B group, which have many advanced charaetaristics, should represent a more advanced group of the genus. The species of AB group were relatively primitive in the genus. Hence the evolutionury trend from AB group to A group and then to B group was possible. This trend is basically correlated with that of morphological evolution. But the above groupings of A, B and AB do not accord with Stearn's taxonomic system and the results of pollen morphology and of chromosome C-bands. 2)E. alpinum, a species distributed in the Mediterranean area, contains a high quantity of A2 kind of compounds (those of A kind with 4'-OH), so it may be somewhat related to the primitive species in China. 3)The constituents of E. davidii and E. ecalcaratnm are almost identical, implying that the prescence or absence of the spur of the petal should be of unimportant systematic significance. 4)The chromngram of HPLC provided reliable evidence for determining the parental origin of the hybrid E. x fanjingshanense. The results of this work provided new evidence for establishing a more reasonable taxonomic system of Epimediurn, but the taxonomic research on Epimedium has a long way to go and more work must be done. Other chemical characteristics of Epimedium and its relationshipwith other groups in the Berberidaceae were also discussed. 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Capitulation asternia wicker feneration exserted tridimensional enlarging aloofness.     

淫羊藿属植物中的黄酮类成分及其分类学意义

用HPLC法研究了具8位异戊烯基的黄酮醇甙类(A类)及一般结构的黄酮醇甙类(B类)在淫羊 藿属Epimedium L.中的存在和含量情况,得到一些具分类学意义的结论。1)依据化学成分可将 Epimedium 分为3群：A群,主要含A类成分;B群,主要含B类成分;AB群,两类化合物含量都高。B 群的8个类群(种或亚种)有多项演化程度较高的形态特征,它可能是Epimedium发展演化中较为进化 的一个分支群。—朋群的种类为本屑较原始的类群,因而在化学性状上有朋群→A群、AB群→B群的 演化趋势,与形态演化趋势基本相关。A、B、AB群的划分与现有分类系统不一致,也与花粉、染色体C 带的结果不很吻合。2)分布于地中海的E. alpinum因有较高含量的厶2类成分(A类中4'-OH的一类 化合物)而体现了与中国的原始类群的一些联系。3)E. davidii和E. ecalcaratum的化学成分几乎相 同,表明花瓣距的有无在Epimedium中的原始类群可能不具重要的分类价值。4)HPLC图谱为E.Х fanjingshanense这一杂交种的亲本来源提供了可靠的证据。本研究结果为建立一个合理的Epimedium的分类系统提供了新的依据。     

沉积物生源要素对水体生态环境变化的指示意义

受人类活动影响,输入到湖泊、河口中的营养盐剧增,导致水体富营养化、食物链结构改变、底质季节性缺氧等生态环境变化。这些环境变化会在沉积物中留下记录,沉积物中生源要素及其稳定同位素的变化是指示水域古生产力、营养盐水平的有效指标。总结归纳了沉积物中生源要素(碳、氮、磷、硅)指标对水体环境中初级生产力、物质来源、营养盐水平3方面变化的指示作用。沉积物中TOC、TN、δ13C、CaCO3和BSi可以反映水体沉降有机质含量和浮游植物的生长状况,是指示水域初级生产力水平的有效指标。根据不同类型植物来源的有机质中δ13C、δ15N和C/N的差异,可以追踪沉积物中有机质的来源。有效地区分有机质来源对于研究人类活动对水体环境的影响及水体富营养化具有重要的价值。沉积物中TN、δ15 N、TP和非磷灰石磷(NAIP)含量的升高直接反映了陆源输入氮、磷的增加。BSi在指示浮游植物生长状况的同时,还反映了水体溶解硅浓度水平和富营养化状况。水体中的生源物质在沉降和埋藏的过程中,会受到早期成岩作用、水动力搬运等众多因素的作用,使沉积物记录的环境变化信息发生改变,从而干扰其对水体环境演变的重建作用。因此综合分析各生源要素指标反映的环境变化信息及其可能的干扰因素,方能正确地反映水域的环境变化过程。