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...     

槭叶小牵牛——中国大陆一新归化种

该研究报道了广东省湛江市霞山区发现的中国大陆旋花科番薯属一新归化种——槭叶小牵牛(Ipomoea wrightii A.Gray)。该种原产热带美洲,引入并归化于中国台湾。通过野外调查,获得该种的详细特征和生境信息,并简要讨论了该种潜在的生态风险。     

中国大陆菊科一归化药用植物——翼茎阔苞菊

报道了在广州发现的菊科阔苞菊属一归化种——翼茎阔苞菊。该种以茎上具翼而与《中国植物志》中收录的3种阔苞菊属植物具有明显区别。该种具有良好的药用价值。     

反枝苋染色体数目的观察(简报)

<正> 反枝苋(Amaranthus retroflexus)为苋科苋属(Amaranthus)的一年生草本。分布于东北,华北和西北等地,原产于美洲热带,为归化植物,生于田园村庄附近的草地上。 其种子作青箱子入药,全草药用:具有治腹泻和痢疾之功效。 本文对反枝苋的体细胞染色体进行了观察,旨在为中药材的良种繁育工作提供必要的细胞学资料。     

中国锦葵科一新记录种——克氏梧桐（英文）

首次报道中国锦葵科一新记录种——克氏梧桐[Firmiana kerrii(Craib) Kosterm.]。该种原记载产自泰国和缅甸,2019年该种在中国云南西双版纳州勐腊县发现有分布。凭证标本保存在中国科学院西双版纳热带植物园标本馆(HITBC)。该文给出了中国已知的9种梧桐属植物的分种检索表。     

中国茄属一新归化种——羽裂叶龙葵

报道了中国茄科茄属的一新记录种——羽裂叶龙葵（Solanum triflorum Nutt.）。该种具有独特的匍匐习性,叶片通常为羽状深裂且稍肉质,花冠呈星芒状,花药细长,在花序轴的顶端通常具一枚叶状小苞片,与国内记载的茄属其他物种区别明显。该种为泛热带分布,原产于美洲,归化于欧洲、南非和澳大利亚,近年来在中国内蒙古自治区亦有归化。     

点叶菊属,中国菊科一新归化属

报道了中国菊科的新归化属种:点叶菊属(Porophyllum Guettard)点叶菊([P.ruderale(Jacquin)Cassini]。点叶菊属原产于美洲,这是本属植物在我国境内归化的首次记录。该种在许多地方表现出入侵性,建议加强动态监测。     

中国一种新归化植物——菱叶苋

报道中国新记录种--菱叶苋(Amaranthus standleyanus Parodi ex Covas),该种原产阿根廷,近来成为北京地区一种归化杂草。     

点叶菊属,中国菊科一新归化属（英文）

报道了中国菊科的新归化属种:点叶菊属(Porophyllum Guettard)点叶菊([P.ruderale(Jacquin)Cassini]。点叶菊属原产于美洲,这是本属植物在我国境内归化的首次记录。该种在许多地方表现出入侵性,建议加强动态监测。     

中国锦葵科一新记录种——克氏梧桐

首次报道中国锦葵科一新记录种——克氏梧桐［Firmiana kerrii (Craib) Kosterm.］。该种原记载产自泰国和缅甸,2019年该种在中国云南西双版纳州勐腊县发现有分布。凭证标本保存在中国科学院西双版纳热带植物园标本馆(HITBC)。该文给出了中国已知的9种梧桐属植物的分种检索表。     

Ascobotryozyma americana gen. nov. et sp. nov. and its anamorph Botryozyma americana, an unusual yeast from the surface of nematodes

A new teleomorphic genus Ascobotryozyma, with a single species, A. americana, is proposed. Its anamorph is a Botryozyma that differs from the type species, B. nematodophila, on distributional, physiological, and molecular criteria; it is described as Botryozyma americana, anam. sp. nov. Ascobotryozyma is characterized by globose asci bearing four lunate ascospores. Fusion of thallus cells precedes ascus formation. Ascobotryozyma americana was isolated from the surface of nematodes (Panagrellus dubius) associated with galleries of the poplar borer (Saperda calcarata) in trembling aspen (Populus tremuloides) in eastern Washington, USA. The teleomorph has not been produced in pure culture.     

Costs of secondary parasitism in the facultative hyperparasitoid Pachycrepoideus dubius: does host size matter?

Although hyperparasitism frequently occur in parasitic insects, many aspects of this strategy remain unknown. We investigated possible fitness costs of hyperparasitism as influenced by host size. Our study was conducted with the facultative hyperparasitoid Pachycrepoideus dubius Ashmead (Hymenoptera: Pteromalidae), which parasitizes host species differing greatly in size. We compared some fitness traits (level of successful parasitism, development time, sex ratio and offspring size) of P. dubius developing on large secondary/primary (Delia radicum L. (Diptera: Anthomyiidae)/Trybliographa rapae Westwood (Hymenoptera: Figitidae)) or small secondary/primary host species (Drosophila melanogaster L./Asobara tabida Nees (Hymenoptera: Braconidae)). In no-choice and choice experiments, P. dubius was able to develop on different stages of T. rapae (L2 (endophagous), L4 (ectophagous), and pupae) but that it preferred to parasitize unparasitized D. radicum pupae over pupae parasitized by T. rapae. Furthermore, in P. dubius, hyperparasitism was associated with fitness costs (lower level of successful parasitism, smaller adult size) and these costs were greater on the smallest host complex. We hypothesize that the size of D. melanogaster pupae parasitized by A. tabida may be close to the suboptimal host size for P. dubius beneath which the costs of hyperparasitism make this strategy nonadaptive. Hyperparasitism in terms of trade-offs between host quality and abundance of competitors is discussed.     

四川省香薷属植物地理分布新记录

报道了四川省香薷属植物地理分布新记录1种——四方蒿(Elsholtzia blanda Benth.)。四方蒿主要分布于中国西南部（云南、贵州、广西）至东南亚及南亚的热带地区,在四川为新记录,且是该种分布区的北缘。凭证标本存放于上海辰山植物园标本馆（CSH）。     

Additional origins of Ownbey's Tragopogon mirus

The allotetraploids (2n = 24) Tragopogon mirus and T. miscellus have become textbook examples of recently and recurrently formed allopolyploids. Both species formed following the introduction of three diploids, T. dubius, T. porrifolius and T. pratensis (each with 2n = 12), from Europe into the Palouse region of eastern Washington and adjacent Idaho, USA, in the early 1900s. The parentage of both allotetraploids is well documented (T. mirus = T. dubius × T. porrifolius; T. miscellus = T. dubius × T. pratensis), and both allotetraploids have formed repeatedly in the past approximately 80 years in the Palouse. On a larger geographical scale, T. mirus has also been reported from Flagstaff, Arizona (AZ), and more recently from Oregon (OR). However, the populations from OR and AZ have not been previously analysed with molecular markers to test the hypothesis of separate origin (vs. long‐distance dispersal). Here, we show that both the AZ and OR collections of T. mirus combine distinctive parental genotypes and are genetically differentiated from the T. mirus genotypes found in the Palouse. The OR sample of T. mirus has a genetically distinct T. dubius contribution that forms a clade in our analyses with a sample of what has been referred to as T. major (now considered a subspecies of T. dubius). Consistent with other naturally occurring T. mirus populations, plastid sequences indicate that T. porrifolius was the maternal parent for both the AZ and OR collections. Microsatellite data are also consistent with local formation of T. mirus from co‐occurring populations of T. dubius and T. porrifolius in OR and AZ. As with sequence data, T. dubius from OR is distinct from other samples of T. dubius at microsatellite loci, contributing a unique signature to T. mirus from this location. It will be useful to include these additional geographical origins of T. mirus, particularly the more genetically distant sample from OR, in ongoing investigations of the genetic and genomic consequences of recent allopolyploidy. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 169 , 297–311.     

Rearing of two predators,Thanasimus dubius andTemnochila virescens, for the biological control ofIps grandicollis in Australia

Rearing methods for two coleopterous predators,Thanasimus dubius andTemnochila virescens, imported into Australia for the biological control ofIps grandicollis, were developed. Bionomic data obtained from laboratory rearings between 1982–1987 showed thatT. dubius eggs took about 7 days to hatch and that duration of the larval stage was about 42 days. Observations showed thatT. dubius had a prolonged prepupal stage (x=56.4 days, range 14–274 days), which was probably non-diapausal in nature. Mean adult longevity was 50 days (range 1–358 days).Temnochila virescens eggs took almost 9 days to hatch, and a lengthy larval stage (x=155.4 days, range 73–333 days) was observed. Mean duration of the pupal stage was 14 days (range 7–28 days). A long preoviposition period (x=141 days, range 47–206 days) was observed, and adults were very long-lived (x=232.7 days, range 14–667 days). Capacity for increase (r_c) calculated from rearing data suggested that numbers ofT. dubius could be increased faster thanT. virescens. Mortality between 1982–1987 averaged about 70% for both species. However, mortality ofT. dubius in 1987 increased significantly, suggesting that inbreeding or other methodological factors could be responsible. A mass-rearing method usingIps-infested pine billets was developed as a cheaper alternative to laboratory rearing, and was shown to be effective in producing large numbers of insects for release.     

Gender- and sequence-dependent predation within group colonizers of defended plants: a constraint on cheating among bark beetles?

Bark beetles engage in one of the most pronounced examples of group procurement of defended plants. Their aggregation pheromones attract both sexes and are essential to overcome constitutive and rapidly inducible lethal defenses. The relative benefits to senders versus receivers of these signals are only partly understood. Because the initial stage of host entry can be hazardous, there may be benefit to a cheating strategy, whose practitioners respond to pheromones but do not engage in host searching. Several disadvantages to cheating have been proposed, but the role of predators has not been considered. Predators exploit bark beetle pheromones to locate prey, accumulate at the breeding site, and consume adult bark beetles before they enter the tree. Preliminary experiments quantified arrival patterns in the field. We used a laboratory assay to investigate relative predation on pioneers (those that initially select and enter hosts) and responders (those that arrive at a host in response to pheromones) during host colonization. Our model system utilized the pine engraver, Ips pini, which exhibits male harem polygamy. We allowed male I. pini to colonize host tissue and added females 1 day later. Also 1 day later, we variably added additional males and predacious checkered beetles, Thanasimus dubius. These treatments included two densities of males and three densities of predators that were selected to emulate field conditions. Responding males experienced higher predation than pioneers. T. dubius ate more males than females, independent of the presence or absence of responding males. T. dubius affected the distribution of females per male, although the number of females that survived to construct ovipositional galleries was constant. We discuss the viability of cheating, implications for biological control, and predator-prey coevolution in this cooperative, group-colonizing herbivore.     

Biologically active compounds from two members of the Asteraceae family: Tragopogon dubius Scop. and Tussilago farfara L.

Tragopogon dubius and Tussilago farfara are consumed as vegetables and used in folk medicine to manage common diseases. Herein, the chemical compositions and biological activities of different leaf extracts (ethyl acetate, methanol, and water) of T. dubius and T. farfara were evaluated. The antibacterial, antifungal, and antioxidant abilities of the extracts were tested using different assays including free radical scavenging, reducing power, phosphomolybdenum, and metal chelating assays. Enzyme inhibitory potentials were evaluated against cholinesterases, tyrosinase, α-amylase and α-glucosidase. Complexes of bioactive compounds (chlorogenic and rosmarinic acid) were docked into the enzymatic cavity of α-glucosidase and subjected to molecular dynamic calculation, enzyme conformational stability, and flexibility analysis. T. dubius and T. farfara extracts showed remarkable antioxidant potentials. Ethyl acetate extracts of T. dubius and T. farfara were the most potent inhibitors of acetylcholinesterase and butyrylcholinesterase. T. dubius ethyl acetate extract and T. farfara methanolic extract showed noteworthy activity against α-glucosidase. High performance liquid chromatography analysis revealed the abundance of some phenolic compounds including chlorogenic and rosmarinic acids. Ethyl acetate extract of T. dubius showed notable antifungal activity against all strains. Docking studies showed best pose for chlorogenic acid was stabilized by a network of hydrogen bonds with residues Asp1157, Asp1279, whereas rosmarinic acid showed several hydrogen bonds with Asp1157, Asp1420, Asp1526, Lys1460 and Trp1369. This study further validates the use of T. dubius and T. farfara in traditional medicine, as well as act as a stimulus for further studies for future biomedicine development.

Communicated by Ramaswamy H. Sarma     

A comparison of populations from the Daphnia similis group (Cladocera: Daphniidae)

European populations of Daphnia similis Claus have been compared with populations from tropical Asia. Daphnia similoides n. sp. from tropical Asia was described as the sibling species of D. similis. The female has characteristic neonate, postabdomen, head, and ephippium. The male has characteristic rostrum, antennules, and the distalmost part of the postabdomen. The D. similis group was compared with D. carinata s. str. Australian populations.     

《广西植物志》秋海棠属(Begonia L.)增订

秋海棠属(Begonia L.)隶属于葫芦目(Cucurbitales)秋海棠科(Begoniaceae),有1 800余种,是世界第六大属,主要分布于美洲、非洲和亚洲的热带和亚热带地区,具有极高的观赏价值,亦可作为药用、食用、饮料和饲料等。我国有秋海棠属植物近300种,主要分布于我国的云南和广西等长江以南地区,其中云南有秋海棠属植物100余种。近年来,随着广西地区秋海棠属植物野外调查的不断深入,陆续发现并发表了大量秋海棠属新类群,使得广西产秋海棠属植物数目已超出1991年《广西植物志》(第一卷)收录的19种,因此亟需对发表于不同期刊中的类群进行系统地整理和汇总。鉴于此,该文通过查阅文献资料和考证标本信息,整理并汇总了广西产秋海棠属植物共84种,包括2个变种、11个亚种和46个特有种,新增的65种为《广西植物志》(第一卷)中未收录的类群,并补充了这些类群的特征集要、凭证标本信息和属下分组概况,为今后开展秋海棠属植物的分类修订以及系统学、进化生物学和保护生物学等研究提供了参考依据。     

不同气候情景下四子柳的亚洲潜在地理分布格局变化预测

四子柳(Salix tetrasperma Roxb.)为杨柳科柳属为数不多的分布区扩展到热带的物种之一,广泛分布于华南和东南亚地区,但其生境破碎化较为严重。该物种具有较高的园林绿化价值和生态价值,预测不同气候情景下该物种的地理分布将为四子柳的资源开发和合理利用乃至柳属的起源和分化研究提供重要的科学依据。利用四子柳全面且精确的分布信息和高分辨率环境数据,基于Maxent模型和ArcGIS空间分析,构建其末次间冰期、末次盛冰期、当代以及未来(2050,2070)的潜在空间分布格局,评价环境因子对分布模型的重要性,定量确定未来受到威胁的适宜生境区域和面积。结果表明,四子柳目前的适宜生境面积为234.65×10~4 km~2,主要位于东亚、南亚和东南亚的热带地区,气温年较差和年均降水量是限制其分布的主要环境因子。总体而言,从冰期至未来,四子柳的分布中心有南北往返迁移的趋势。四子柳在末次盛冰期时向西北方向扩张并开始出现于热带地区,表明该物种开始适应热带气候,进入全新世中期以后种群收缩并退缩到云贵高原的河谷地区和印度尼西亚的平原区域。随着全球气候变暖,在不同二氧化碳浓度路径下2050年和2070年四子柳的潜在适生境有可能破碎化增加,建议对缅甸东部及中部成片减少的边缘群体进行实时监测。