中国苋属nrDNA的ITS序列分析及其系统学意义

运用ＰＣＲ直接测序法,对苋属（Ａｍａｒａｎｒｈｕｓ Ｌ．）１５个种及外类群鸡冠花（Ｃｅｌｏｓｉａ ｃｒｉｓｔａｔａ Ｌ．）ｎｒＤＮＡ的ＩＴＳ区（包括ＩＴＳ－１,５．８５ｒＤＮＡ和ＩＴＳ－２）进行序列测定。结果表明苋属植物的ＩＴＳ序列总长度为６２９－６３２ｂｐ,长度变异仅发生在ＩＴＳ－１区（２５０－２５３ｂｐ）。采用ＰＡＵＰ软件进行系统发育分析表明：分布于中国的苋属植物可分为３组,即刺苋组（ｓｅｃｇ     

Sequence Analysis of the ITS Region of Nuclear Ribosomal DNA (nrDNA) in Chinese Amaranthus and Its Systematic Utility

The sequences of the ITS region (including ITS-1, 5.8S rDNA and ITS-2) of nuclear ribosomal DNA from 15 species of the genus Amaranthus L. and outgroup Celosia cristata L. were determined. The result shows that the size of the ITS region of Amaranthus is from 629 to 632 bp, and the length variation is only found in ITS-1 (250-253 bp). On the basis of phylogenetic analysis of nucleotide sequences, the Amaranthus species in China may be devided into three sections, viz., sect. Spinosus, sect. Amaranthus and sect. Paucestamen; the cultivated species, viz., Amaranthus paniculatus L., A. cruentus L., A. caudatus L. and A. hypochondriacus L. can be treated as the subsp. of A. hybridus L.; A. taishanensis F.Z.Li and A. tenuifolius Willd are both closely related to species in the sect. Paucestamen. The study also indicated that the number of stamens has more phylogenetic information than other characters, such as the number of sepals and dehiscence/indehiscence of fruits in Amaranthus.     

中国苋属植物酯酶同工酶研究

用聚丙烯酰胺凝胶盘状电泳技术对中国苋属植物１３种的酯酶同工酶谱进行了研究。结果表明：苋属植物酯酶同工酶有２条属的标志带在生化水平上认为是一个自然的分类群;     

Comparative analysis of phylogenetic relationships of grain amaranths and their wild relatives (Amaranthus; Amaranthaceae) using internal transcribed spacer, amplified fragment length polymorphism, and double-primer fluorescent intersimple sequence repeat markers.

The most economically important group of species in the genus Amaranthus is the A. hybridus species complex, including three cultivated grain amaranths, A. cruentus, A. caudatus, and A. hypochondriacus, and their putative wild progenitors, A. hybridus, A. quitensis, and A. powellii. Taxonomic confusion exists among these closely related taxa. Internal transcribed spacer (ITS) of nuclear ribosomal DNA, amplified fragment length polymorphism (AFLP), and double-primer fluorescent intersimple sequence repeat (ISSR) were employed to reexamine the taxonomic status and phylogenetic relationships of grain amaranths and their wild relatives. Low ITS divergence in these taxa resulted in poorly resolved phylogeny. However, extensive polymorphisms exist at AFLP and ISSR loci both within and among species. In phylogenetic trees based on either AFLP or ISSR or the combined data sets, nearly all intraspecific accessions can be placed in their corresponding species clades, indicating that these taxa are well-separated species. The AFLP trees share many features in common with the ISSR trees, both showing a close relationship between A. caudatus and A. quitensis, placing A. hybridus in the same clade as all grain amaranths, and indicating that A. powellii is the most divergent taxon in the A. hybridus species complex. This study has demonstrated that both AFLP and double-primer fluorescent ISSR have a great potential for generating a large number of informative characters for phylogenetic analysis of closely related species, especially when ITS diversity is insufficient.     

中国新归化种广布苋的分布及其与腋花苋的关系

本文报道了中国苋科苋属的一新记录归化植物——广布苋(Amaranthus graecizans L.).该种植株常匍匐,叶片狭长椭圆形至线状披针形,有时线形或菱形卵形,长至少为宽的2.5倍,花被片3枚,近等长,与中国有分布的本属其他物种有所区别.该种原产于欧洲地中海地区、非洲北部至亚洲西部,归化于欧洲其他地区、东亚、澳...     

Amplified fragment length polymorphism-based genetic relationships among weedy Amaranthus species

Weedy Amaranthus species frequently cause economically significant reductions in crop yields. Accurate identification of Amaranthus species is important for efficient weed control, but Amaranthus species can interbreed, which might cause difficulty when identifying hybrid-derived specimens. To determine which of several economically important weedy Amaranthus species are most genetically similar, and thus most likely to produce viable hybrids, we performed amplified fragment length polymorphism (AFLP)-based unweighted pair group method with arithmetic mean (UPGMA) analysis on 8 of these species, with 141 specimens representing 98 accessions. The analysis grouped the specimens into four principal clusters composed of Palmer amaranth (Amaranthus palmeri S. Wats.) and spiny amaranth (Amaranthus spinosus L.); Powell amaranth (Amaranthus powellii S. Wats.), redroot pigweed (Amaranthus retroflexus L.), and smooth pigweed (Amaranthus hybridus L.); waterhemp (Amaranthus tuberculatus (Moq.) Sauer) and sandhills amaranth (Amaranthus arenicola I.M. Johnst.); and tumble pigweed (Amaranthus albus L.). The cluster analysis provided evidence suggesting hybridization among Powell amaranth, redroot pigweed, and smooth pigweed. Further investigations using molecular analysis of the ribosomal internal transcribed spacer region from atypical plants supported this notion. Three species, Palmer amaranth, sandhills amaranth, and waterhemp, are dioecious; nevertheless, the Palmer amaranth and waterhemp-sandhills amaranth clusters were distinct from each other. The Palmer amaranth-spiny amaranth cluster included a cluster of Palmer amaranth and two clusters of spiny amaranth, a monoecious species. Thus the dioecious species Palmer amaranth and waterhemp may not necessarily hybridize with each other more readily than they would to one or more of the monoecious Amaranthus species.     

微波法和超声波法提取绿穗苋多糖响应面优化研究

绿穗苋是一种药食兼用作物,其中多糖成份具有很高的药食价值。本研究以绿穗苋地上部分为材料,以微波和超声波两种方法对绿穗苋多糖进行提取,并通过响应面分析法对提取进行优化,确定最佳工艺,通过水提醇沉的方法得到绿穗苋粗多糖。综合比较两种提取工艺,提取效果最佳工艺为微波提取法。其条件为:提取时间41.42 min,提取功率211.65 W,料液比1:33.338 (g/mL),实际得率为13.25%。该研究结果促进绿穗苋资源的有效利用,为绿穗苋多糖的提取工艺及产品的开发利用提供理论依据。     

Morphological Evidence for the Phylogeny of Cetacea

A cladistic analysis of 54 extant and extinct cetacean taxa scored for 304 morphological characters supports a monophyletic Odontoceti, Mysticeti, Autoceta, and Cetacea. Forcing a sister-group relationship between Mysticeti and Physeteridae, as suggested by some, but not all, molecular studies, requires an additional 72 steps. In agreement with recent molecular studies, morphological data divide extant mysticetes into two clades: Balaenopteroidea (Eschrichtiidae + Balaenopteridae) and Balaenoidea (Balaenidae + Neobalaenidae). Cetotheriopsinae is removed from Cetotheriidae, elevated to Family Cetotheriopsidae, and placed within the Superfamily Eomysticetoidea. All extant mysticetes and all cetotheriids are placed in a new Parvorder Balaenomorpha, which is diagnosed by many morphological characters, including fusion of the anterior and posterior processes of petrosal to ectotympanic bulla, pronounced median keel on palate, and absence of ventral margin of sigmoid process of bulla. Many of the clades within Odontoceti in the most parsimonious trees of this study are at odds with recent phylogenetic analyses. For example, Platanistidae is not closely related to the extinct odontocete families Squalodontidae and Squalodelphinidae. Instead, it is more closely related to extant river-dwelling odontocetes (i.e., Lipotes, Inia), suggesting a single dispersal of odontocetes into freshwater habitats. We found several characters to support Physeteroidea (Physeteridae + Ziphiidae), a taxon considered paraphyletic by several molecular and some morphological analyses. Lack of agreement on the phylogeny within Odontoceti indicates that additional analyses, which include molecular and anatomical data as well as extant and extinct taxa, are needed.     

Phylogeny of Rosellinia capetribulensis sp. nov. and its allies (Xylariaceae)

A new Rosellinia species, R. capetribulensis isolated from Calamus sp. in Australia is described. R. capetribulensis is characterized by perithecia immersed within a carbonaceous stroma surrounded by subiculum-like hyphae, asci with large, barrel-shaped amyloid apical apparatus and large dark brown spores. Morphologically, R. capetribulensis appears to be similar to R. bunodes, R. markhamiae and R. megalospora. To gain further insights into the phylogeny of this new taxon we analyzed the ITS-5.8S rDNA using maximum parsimony and likelihood methods. In addition, a morphological dataset also was analyzed phylogenetically to investigate possible affinities. ITS rDNA based phylogenies reveal that R. capetribulensis is closely related to other Rosellinia species showing closest affinity to R. arcuata, RL necatrix and R. pepo. However, analysis of R. capetribulensis forms an unsupported branch sister to these taxa. Results from the morphological matrix indicate a close morphological affinity to members of Rosellinia subgenus Rosellinia. Despite that ITS rDNA and morphological analyses present difficulties in constructing a proper phylogenetic framework among Rosellinia and allied genera, there is sufficient evidence to support the establishment of the new taxon in the genus Rosellinia. The morphological similarities and differences between R. capetribulensis and allied genera such as Astrocystis and Entoleuca are also briefly discussed.     

浙江新外来入侵植物——合被苋

合被苋Amaranthus polygonoides L.原产加勒比海岛、美国、墨西哥等地,是新近传入浙江的外来植物。本文报道合被苋的植物学和生态学特性,介绍其在国内外分布和国内蔓延情况,为该种的早期控制提供基础资料。     

PHYLOGENETIC RELATIONSHIPS OF GELIDIALES SPECIES IN COSTA RICA

Despite a general paucity of studies on marine algae in Costa Rica, within the red algal order Gelidiales, 9 species are reported from the Caribbean, and 6 species from the Pacific. In this study 5 species from the southeast Caribbean coast and 2 species from the northwest Pacific coast of Costa Rica were collected for DNA sequence and morphological analyses. At the time of this writing, morphological observations of four Caribbean taxa have identified them as Gelidium microdonticum , Pterocladiella capillacea , P. melanoidea , and Gelidiella acerosa. In rbc L sequence analyses, Gelidium microdonticum is resolved within a clade of small Gelidium species predominantly found in the south Atlantic. Two collections representing different forms of Pterocladiella melanoidea sensu Dawson were found to have identical rbc L sequences. These samples were resolved in rbc L trees with a taxon from Texas identified as P. bartlettii and not P. melanoidea from Europe. Comparisons with type material are being made to verify these identifications so that the status of P. melanoidea in the Caribbean may be determined. The unidentified Caribbean taxon is resolved as a distinct species within the Pterocladiella clade as well. Gelidiella acerosa from Caribbean Costa Rica is closely allied with other Caribbean G. acerosa samples in rbc L trees. The two pacific taxa are small intertidal turf species and have not yet been identified. Sequence analyses resolve these taxa within a large clade of Indo-Pacific and Caribbean Gelidium species.     

Copia 类型反转录转座子在籽粒苋中的表现

利用籽粒苋为材料 ,通过PCR扩增、克隆研究了copia类型反转录转座子的反转录酶序列在籽粒苋中的表现 ,结果表明 :(1)反转录转座子在苋属的 30个品系中同时检测到 ,说明反转录转座子在籽粒苋的不同种中普遍存在 ;(2 )对野生苋 (A .quitensis)中克隆、序列分析 2 8个反转录转座子的反转录酶序列 ,碱基分析表明 ,它们存在高度异质性 ,不同的反转录酶序列均存在不同程度的碱基缺失突变和终止密码子的突变 ;(3)对 2 8个序列与已发表的一些不同物种 (如水稻、矮牵牛和果蝇等 )的同一类型序列聚类分析表明 ,存在于野生苋中的反转录转座子与来源于双子叶或单子叶植物的反转录转座子关系密切 ,它们与果蝇的copia因子和 1731因子可能具有相同的起源     

The skull and the palaeoecological significance of Labidosaurus hamatus, a captorhinid reptile from the Lower Permian of Texas

The cranial skeleton of the large captorhinid reptile Labidosaurus hamatus , known only from the Lower Permian of Texas, is described on the basis of new, undescribed specimens. Labidosaurus is distinguished from other captorhinids by the more extreme sloping of the ventral (alveolar) margin of the premaxilla, a low dorsum sellae of the parabasisphenoid, a reduced prootic, a narrow stapes, and a relatively small foramen intermandibularis medius. Despite the presence of a single row of teeth in each jaw, the skull of Labidosaurus resembles most closely those of moradisaurines, the large multiple-tooth-rowed captorhinids of the latest Early and Middle Permian. A phylogenetic analysis confirms that the single-tooth-rowed L. hamatus is related most closely to moradisaurines within Captorhinidae, a relationship that supports the hypothesis of a diphyletic origin for multiple rows of marginal teeth in captorhinids (in the genus Captorhinus and in the clade Moradisaurinae). In view of the close relationship between L. hamatus and moradisaurines, which are regarded to have been herbivorous, L. hamatus is a critical taxon for studies of the evolution of herbivory in early tetrapods. L. hamatus shares several trademark features of herbivorous adaptation with moradisaurines, which suggest that this captorhinid species was omnivorous. As such, it represents a transitional taxon between faunivorous basal reptiles and the herbivorous moradisaurines.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 149 , 237–262.     

Species delimitation in the Luziola peruviana (Poaceae) complex

Luziola is a small genus from aquatic environments of the New World. The most widespread species in the genus isL. peruviana. Morphological variation has been documented for this species throughout its entire range of distribution, however this variation has been difficult to characterize. A population aggregation analysis was performed in order to determine how many species can be identified when analyzing characters from the individuals of this taxon as well as with individuals from closely related taxa such asL. divergens, L. doelliana, andL. pittieri. Multivariate analysis, ANOVA and ANCOVA analyses were also performed to detect if quantitative morphological variation is related to altitude and latitude. Results indicate that within this complex only one species should be recognized, referable toL. peruviana, and that plants near the equator are larger, and have larger lemmas and paleas in both female and male flowers. An identification key for the nine species now recognized inLuziola is included.     

Three species of Isotoma (Collembola, Isotomidae) based on morphology, isozymes and ecology

Morphological markers and isozymes were used for identifying three presumed species of the Isotoma genus. Morphological traits separated three taxa of the genus. 10 isozymes determined by at least 11 loci were analysed from each taxon, and 2 loci were taxon-specific, supporting the hypothesis that the three taxa represented three species. The genetic variation found within the taxa measured as fraction of polymorphic loci at the 99% level was 0.82, 0.55 and 0.55 with the corresponding observed heterozygosity 0.15, 0.09 and 0.12. Two populations of the same taxon from Denmark and Norway, respectively, were very closely related. Additional ecological criteria, obtained from a literature survey, also revealed pronounced differences between the three taxa. Due to these facts three distinct species are proposed, namely I. anglicana Lubbock 1862, I. riparia Nicolet 1841 and I. viridis Bourlet 1839.     

Short-Term Impact of a Permanent Magnetic Field on the Physiological,Morphological, and Biochemical Characteristics of Amaranthus retroflexus,Agastache rugosa,and Thlaspi arvense Seedlings

Russian Journal of Plant Physiology - The physiological, morphological, and biochemical characteristics of seedlings of common amaranth (Amaranthus retroflexus L.), blue licorice (Agastache rugosa...     

A New Coastal Species of Limonium (Plumbaginaceae) from Southeastern Spain

A new species, Limonium scopulorum (Plumbaginaceae), is described from the maritime cliffs of Alicante province, Spain (southeastern part of the Iberian Peninsula). This new taxon belongs to the group of Limonium delicatulum, which is highly diversified in the Mediterranean territories of the Iberian Peninsula. It is related to the Balearic species L. biflorum, though several leaf, floral and chromosomal features warrant its easy recognition. Molecular divergence, shown in previous studies, also supports its separate treatment. Major affinities and differences with other related taxa are discussed. Moreover, morphological, ecological, chorological, biogeographic features of the new taxon are discussed, and its conservation status is reported. An identification key is provided for Spanish taxa of the Limonium delicatulum group.     

Comparative morphology of the leaf epidermis in Schisandra (Schisandraceae)

The leaf epidermis of 127 samples representing ten species within Schisandra Michaux. and one species of the related genus, Kadsura Kaempf. ex Juss., was investigated using light and scanning electron microscopy. Many characters of the leaf epidermis in Schisandra , such as pattern of epidermal cells, type of stomata, shape of guard cell pairs and cuticular ornamentation, are usually constant within species and thus make good characters for studying the relationship between and within genera. A new character, rim number, of the outer stomatal rim in the genus is introduced. It is shown that double outer stomatal rims occur only in evergreen Schisandra species, whereas a single rim occurs in deciduous species. This character supports the classification of Schisandra into two subgenera based on habit and androecial organs. This classification is also supported by additional morphological and molecular taxonomic characters. Kadsura coccinea (Lem.) Smith A. C. is the most primitive taxon in the related genus Kadsura . The outer stomatal rim of this species also has double rims. Combined with morphological and molecular evidence, this suggests that Schisandra and Kadsura are closely related and may share a recent common ancestor.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 39–56.