北京唇形科一新记录属——龙头草属

该文报道了发现于北京市密云区的1种被子植物新记录——荨麻叶龙头草[Meehania urticifolia(Miq.)Makino],其所隶属的龙头草属(Meehania Britton)为北京分布新记录。描述了荨麻叶龙头草的形态特征与生境,凭证标本藏于浙江大学标本馆(HZU)。荨麻叶龙头草于1899年首次发现于日本,是东北亚分布植物,此前在中国仅分布于东北。北京云蒙山发现的分布点,显然是该种目前在中国分布最西的分布点,可能于冰川期从东北亚迁移而来。     

金喜楼梯草(荨麻科),越南楼梯草属植物一新种（英文）

对产自越南的荨麻科楼梯草属植物一新种金喜楼梯草(Elatostema kimhyense Y.G.WeiV.T.Do)作了描述和绘图。该种生长于海拔350~400和1 100~1 200 m的石灰岩山地林下。该新种与越南楼梯草(E.vietnamense Q.LinL.D.Duan)接近,区别在于其拥有肉质茎,羽状脉,叶背面、苞片和小苞片被微硬毛。     

云南省凤仙花属(凤仙花科)2新记录种

报道了云南省凤仙花科(Balsaminaceae)凤仙花属(Impatiens L.)植物2新记录,即睫毛萼凤仙花(I.blepharosepala Pritz.ex Diels)和红雉凤仙花(I.oxyanthera Hook.f.),并提供了形态描述及其图片,凭证标本保存于重庆三峡学院生命科学与工程学院植物标本馆。该报道的睫毛萼凤仙花花色为白色,红雉凤仙花植株茎、叶皆被微柔毛,茎有分枝,小枝细,丰富了2个物种的形态描述。     

空心莲子草是观察植物导管的好材料

笔者采集到空心莲子草、南瓜、繁缕等多种植物的茎进行对比实验发现：苋科植物空心莲子草(Altemanthera philoxemides)的茎是观察植物导管的好材料。现介绍如下：     

4种北极被子植物叶片显微结构和超微结构研究

以采自北极的4种被子植物(高山发草Deschampsia alpina、无茎蝇子草Silene acaulis、仙女木Dryasocto-petala,极柳Salix polaris)为材料,利用光学显微镜和透射电子显微镜,研究了它们叶片显微结构和超微结构.结果显示;(1)高山发草和无茎蝇子草的叶片为等面叶,仙女木和极柳为两面叶,无茎蝇子草和极柳叶肉中含有异细胞;(2)4种植物的细胞超微结构均具有叶绿体紧贴细胞壁分布、叶绿体基质中含有淀粉粒、线粒体紧密地围绕在叶绿体周围的特征,而且高山发草和无茎蝇子草的类囊体出现膨胀,无茎蝇子草和仙女木的细胞基质有大量囊泡,极柳叶绿体内膜附近存在周质网.研究表明,北极植物叶片的结构特点与南极植物和高山植物具有一定的相似之处,北极植物叶片的显微结构和超微结构特征更有利于其适应北极的极端环境.     

中国西南特有翅茎草属的种间界定——基于形态学和分子系统学分析

翅茎草属(Pterygiella)是中国西南地区特有的半寄生植物.翅茎草属4种植物形态差异不显著,种的界定依据较模糊;此外,杜氏翅茎草2变种的划分依据也存在疑问.本研究选取了翅茎草属4种13个居群,通过数量性状的主成分分析和质量性状的非加权组平均法聚类分析;结合叶绿体4个片段(即atpB-rbcL、trnD-trnT、trnS-trnG和sbA-trnH)和核基因组的ITS片段研究,对该属下的种类划分作了重新界定.研究表明:翅茎草属应包括3种,即翅茎草、杜氏翅茎草和圆茎翅茎草;川滇翅茎木应作为圆茎翅茎草的变种.对杜氏翅茎草指定了后选模式,该种仅包括茎无毛的个体,而茎疏被毛的个体应归入翅茎草中.基于以上研究结果,本文提出了一个新的翅茎草属分种检索表,并做了分类修订.     

喜旱莲子草入侵群落土壤对植物生长的影响

分别以受喜旱莲子草(Alternanthera philoxeroides)入侵和未受喜旱莲子草入侵的当地植物群落土壤为生长基质,比较不同基质上入侵植物喜旱莲子草和同属的土著植物莲子草(A.sessilis)的生长指标,探讨喜旱莲子草入侵群落土壤对喜旱莲子草及莲子草生长的影响机制。结果表明,喜旱莲子草入侵群落土壤抑制了莲子草的生长,显著降低了根生物量、茎生物量和总生物;改变了形态特征,显著降低了分枝数量、茎长度、根长、根体积;减少了对根的生物量分配,显著抑制了根质量比与根冠比。喜旱莲子草入侵群落土壤对入侵植物喜旱莲子草的生物量、分枝数量、茎长度、根长、根体积没有显著的抑制作用,而显著增加了其叶片数量和叶质量比。这种效应将有利于喜旱莲子草在入侵地形成单优群落,表明土壤在喜旱莲子草成功入侵中起了重要作用。     

中国石竹科蝇子草属一新记录种——硬骨草叶蝇子草北大核心CSCD

报道了中国石竹科蝇子草属一新记录种——硬骨草叶蝇子草(Silene holosteifolia Bocquet et Chater),并根据标本首次提供了该物种完整的形态描述和线描图。硬骨草叶蝇子草先前发现于尼泊尔和不丹,现发现于中国西藏自治区日喀则市的吉隆和聂拉木两县境内。硬骨草叶蝇子草与花脉蝇子草(S.multifurcata C.L.Tang)形态上最为相近,主要区别在于硬骨草叶蝇子草的花常单生,苞片卵状披针形,花萼钟形或圆球形,且纵脉黑色,在萼齿处脉端不连合,花瓣黄绿色,多次分裂,流苏状,裂片近线形,花柱3。凭证标本存于中国科学院植物研究所植物标本馆、昆明植物所标本馆和美国史密森学会。     

金喜楼梯草(荨麻科),越南楼梯草属植物一新种

对产自越南的荨麻科楼梯草属植物一新种金喜楼梯草（Elatostema kimhyense Y.G.Wei & V.T.Do）作了描述和绘图。该种生长于海拔350~400和1 100~1 200 m的石灰岩山地林下。该新种与越南楼梯草（E.vietnamense Q.Lin & L.D.Duan）接近,区别在于其拥有肉质茎,羽状脉,叶背面、苞片和小苞片被微硬毛。     

大气CO_2浓度升高对红三叶和高丹草Cs、K竞争吸收与转运的影响

水培条件下,研究了大气C02浓度升高对红三叶(Trifolium Pratene L.)和高丹草(Sorhum vulgare x Sorghum.vulgare va r.sudanense hybrids)在不同铯(Cs)浓度(0、200、500、1 000μmol·L~(-1))下生物量、铯和钾的竞争吸收及转运的影响。结果表明,大气CO_2浓度升高显著提高了2种植物叶、茎和根各部位的生物量,其中,红三叶各部生物量分别提高了42.6%、66.2%和45.0%,高丹草分别提高了17.4%、18.9%和22.3%。大气CO:浓度升高提高了红三叶和高丹草叶片及茎中的Cs含量,提升比例最大的为红三叶的茎(达9.7%),同时显著提高了2种植物对Cs的转运系数及红三叶的茎和根中Cs/K的区别系数。对于红三叶,大气CO_2浓度升高引起叶片K含量略微增加,而茎和根系中K含量显著降低;对于高丹草,大气CO_2浓度升高引起叶片和茎中K含量增加,而根系中K含量降低。2种植物对Cs的吸收都与介质中Cs浓度呈显著的线性相关,溶液中Cs浓度的增加提高了红三叶和高丹草的Cs/K区别系数,并且Cs的添加不仅对红三叶和高丹草的生物量都起到了一定的抑制作用,同时还降低了2种植物对钾的吸收。在正常的CO_2浓度下,1000μmol·L~(-1)Cs处理可使2种植物叶、茎和根中的K含量分别降低10.4%、13.3%、32.5%(红三叶)和18.3%、42.1%和38.9%(高丹草);在大气C02浓度升高的条件下,分别降低12.2%、22.0%、35.0%(红三叶)和17.9%、38.7%、34.6%(高丹草)。     

重庆凤仙花科植物1新记录种——太子凤仙花

该文报道重庆市1新记录种——太子凤仙花(Impatiens alpicola Y.L.Chen et Y.Q.Lu),并描述该新记录种的形态特征和生境分布,凭证标本存放于重庆三峡学院生命科学与工程学院植物标本馆。另编制了重庆市分布凤仙花属植物分种检索表。     

Corydalis hirtipes B.U. Oh et J.G. Kim: A new species ofCorydalis sectCorydalis (Fumariaceae) from Korea

Here we describe a new species ofCorydalis sectCorydalis (Fumariaceae), namely C.hirtipes B.U. Oh et J.G. Kim. This species, from the central part of Korea, is clearly distinguished from other species of sectCorydalis by its simple, unicellular hairs that are densely distributed on the stems, peduncles, and petioles. It is also distinctive from its close relative C.albipetala in having ternate leaves, lobate or parted leaflets, dentate or cleft bracts, and broad, fusiform fruits.     

中国蜾蠃属两新种及西南地区种类检索表（膜翅目：胡蜂科：蜾蠃亚科）

记述中国蜾蠃属Eumenes Latreille 2新种:锈触蜾蠃E. ferrugiantennus sp. nov.和黑盾蜾蠃E. nigriscutatus sp. nov.。锈触蜾蠃E. ferrugiantennus与E. placens Nurse, 1903近似,但前者体覆锈红色斑点及大的刻点,腹部第2节背板中部有1条黑色斑纹,雌性整个触角锈红色。黑盾蜾蠃E. nigriscutatus与分布于台湾的E. tosawae tosawae Soika, 1941近似,但前者覆有彩色斑纹,头胸腹均覆有较大的刻点,腹部第 2 节背板前端部有 1 较深的凹陷以形成 1 明显的翘状结构。文中还提供了西南地区种类检索表。新种模式标本保存于重庆师范大学昆虫与分子生物学研究所。     

Anaerobic induced ethanol synthesis in the stems of greenhouse-grown conifer seedlings

Ethanol synthesis was induced in stem segments from greenhouse-grown conifer seedlings by placing them in a N₂ atmosphere at 30 °C for 24 h. Stems from ponderosa pine,Pinus ponderosa Dougl. ex Laws., sugar pine,Pinus lambertiana Dougl., Pacific silver fir,Abies amabalis Dougl. ex Forbes, and lodgepole pine,Pinus contorta Dougl. ex Loud, produced the highest quantities of ethanol. This group also had the smallest and slowest growing stems. Within each of these species the amount of ethanol produced was inversely related to the stem volume. Stems from western hemlock,Tsuga heterophylla (Raf.) Sarg., grand fir, Abies grandis Dougl. ex Forbes, Douglas-fir,Pseudotsuga menziesii (Mirb.) Franco, and western redcedar,Thuja plicata Donn ex D. Don, all produced equivalent but low ethanol concentrations. These species had the largest and fastest growing stems. In this group only grand fir exhibited an inverse relationship between ethanol concentrations and stem volume. The relative amounts of ethanol synthesized by stems from Douglas-fir, western hemlock and western redcedar seedlings were not the same as subsequently observed in logs from mature trees of the same species under field conditions. Differences in the anaerobic environments for the two stem types could have affected the quantities of ethanol produced. The observed high amounts of ethanol produced by the stems from pine species were discussed in terms of their ability to handle periods of anaerobic stress or hypoxia.     

Trichoderma species form endophytic associations within Theobroma cacao trichomes

Trichoderma species are usually considered soil organisms that colonize plant roots, sometimes forming a symbiotic relationship. Recent studies demonstrate that Trichoderma species are also capable of colonizing the above ground tissues of Theobroma cacao (cacao) in what has been characterized as an endophytic relationship. Trichoderma species can be re-isolated from surface sterilized cacao stem tissue, including the bark and xylem, the apical meristem, and to a lesser degree from leaves. SEM analysis of cacao stems colonized by strains of four Trichoderma species (Trichoderma ovalisporum-DIS 70a, Trichoderma hamatum-DIS 219b, Trichoderma koningiopsis-DIS 172ai, or Trichoderma harzianum-DIS 219f) showed a preference for surface colonization of glandular trichomes versus non-glandular trichomes. The Trichoderma strains colonized the glandular trichome tips and formed swellings resembling appresoria. Hyphae were observed emerging from the glandular trichomes on surface sterilized stems from cacao seedlings that had been inoculated with each of the four Trichoderma strains. Fungal hyphae were observed under the microscope emerging from the trichomes as soon as 6 h after their isolation from surface sterilized cacao seedling stems. Hyphae were also observed, in some cases, emerging from stalk cells opposite the trichome head. Repeated single trichome/hyphae isolations verified that the emerging hyphae were the Trichoderma strains with which the cacao seedlings had been inoculated. Strains of four Trichoderma species were able to enter glandular trichomes during the colonization of cacao stems where they survived surface sterilization and could be re-isolated. The penetration of cacao trichomes may provide the entry point for Trichoderma species into the cacao stem allowing systemic colonization of this tissue.     

Behavioral Responses and Interactions of Estuarine Animals With an Invasive Marsh Plant: A Laboratory Analysis

Invasion by Phragmites australis into tidal marshes previously dominated by Spartina alterniflora is viewed as a serious environmental threat along the Atlantic coast of the US, but little is known about the relative habitat value of the two plants for most estuarine species. This study was designed to investigate behavioral responses, in the laboratory, of three species to the two plants. Fiddler crabs, Uca pugnax, grass shrimp, Palaemonetes pugio, and larval mummichogs (killifish), Fundulus heteroclitus were introduced into aquaria with a bare area, an area with dead Phragmites stems, and an area with dead Spartina stems. All species distributed themselves equally between the Spartina and the Phragmites. The behavior of larval mummichogs in the tanks with predators was observed. In the presence and absence of stems, they utilized the surface of the water as a refuge, as well as the stems, when present. This behavior was equally as effective as being among the stems in promoting larval survival. In microcosms with blocks of marsh with living plants, fiddler crabs and grass shrimp again did not show a preference for either species of plant, while juvenile and adult mummichogs were not consistent. Small fish chose Spartina when in the small microcosm and had no preference in the large one. Large fish chose Spartina in the small microcosm and Phragmites in the large one. Predation by adult mummichogs on grass shrimp was comparable in Spartina and Phragmites microcosms, and predation on tethered shrimp was equivalent in adjacent Spartina and Phragmites marshes in the field.     

Characterization of three endophytic, indole-3-acetic acid-producing yeasts occurring in Populus trees

Three endophytic yeast, one isolated from stems of wild cottonwood (Populus trichocarpa), two from stems of hybrid poplar (P. trichocarpa × Populus deltoides), were characterized by analyzing three ribosomal genes, the small subunit (18S), internal transcribed spacer (ITS), and D1/D2 region of the large subunit (26S). Phenotypic characteristics of the yeast isolates were also obtained using a commercial yeast identification kit and used for assisting the species identification. The isolate from wild cottonwood was identified to be closest to species Rhodotorula graminis. The two isolates from hybrid poplar were identified to be species Rhodotorula mucilaginosa. In addition, the three yeast isolates were observed to be able to produce indole-3-acetic acid (IAA), a phytohormone which can promote plant growth, when incubated with l-tryptophan. To our knowledge, the yeast strains presented in this study were the first endophytic yeast strains isolated from species of Populus.     

庆元香科科,浙江唇形科一新种

该文描述了采自浙江南部庆元县的唇形科(Lamiaceae)香科科属(Teucrium L.)一新种:庆元香科科(T.qingyuanense),并附有线描图.庆元香科科与峨眉香科科(T.omeiense)和香科科(T.simplex)接近,与峨眉香科科的区别在于其茎、花序轴和花梗均密被倒向短柔毛,花萼外面被短柔毛和腺点...     

Trichoderma theobromicola and T. paucisporum: two new species isolated from cacao in South America

Trichoderma theobromicola and T. paucisporum spp. nov. are described. Trichoderma theobromicola was isolated as an endophyte from the trunk of a healthy cacao tree (Theobroma cacao, Malvaceae) in Amazonian Peru; it sporulates profusely on common mycological media. Trichoderma paucisporum is represented by two cultures that were obtained in Ecuador from cacao pods partially infected with frosty pod rot, Moniliophthora roreri; it sporulates sporadically and most cultures remain sterile on common media and autoclaved rice. It sporulates more reliably on synthetic low-nutrient agar (SNA) but produces few conidia. Trichoderma theobromicola was reintroduced into cacao seedlings through shoot inoculation and was recovered from stems but not from leaves, indicating that it is an endophytic species. Both produced a volatile/diffusable antibiotic that inhibited development of M. roreri in vitro and on-pod trials. Neither species demonstrated significant direct in vitro mycoparasitic activity against M. roreri.