淫羊藿属十二个种的核型

用细胞压片法对12个淫羊藿属(Epimedium)植物的根尖有丝分裂进行了观察,并对其核型进行了比较研究。结果表明:这12种淫羊藿在核型上基本相似,都有1对中间随体染色体,而且都为对称核型。粗毛淫羊藿(E.acuminatum)、印江淫羊藿(E.yinjiangense)、单叶淫羊藿(E.simplicifloum)、巫山淫羊藿(E.wushanense)、光叶淫羊藿(E.myrianthum)、宝兴淫羊藿(E.davidi)、罗甸淫羊藿(E.luodianense)、木鱼坪淫羊藿(E.franchetii)、箭叶淫羊藿(E.sagittatum)、E.pubigerum、高山淫羊藿(E.alpinum)等11个种的核型公式均为2n=2x=6m(2SAT) 6sm,而黔岭淫羊藿(E.leptorrhizum)的核型公式为2n=2x=8m(2SAT) 4sm。结果显示12种淫羊藿的体细胞染色体数目均为2n=12,基数X=6;都属于对称核型、都有1对中间随体;染色体均为m、sm两种类型。     

淫羊藿属十二个种的核型

用细胞压片法对12 个淫羊藿属( Epimedium) 植物的根尖有丝分裂进行了观察, 并对其核型进行了比较研究。结果表明: 这12 种淫羊藿在核型上基本相似, 都有1 对中间随体染色体, 而且都为对称核型。粗毛淫羊藿( E. acuminatum) 、印江淫羊藿( E . yinjiangense )、单叶淫羊藿( E. simplicifloum) 、巫山淫羊藿( E. wushanense) 、光叶淫羊藿( E. myrianthum) 、宝兴淫羊藿( E. davidi) 、罗甸淫羊藿( E. luodianense) 、木鱼坪淫羊藿( E. franchetii ) 、箭叶淫羊藿( E. sagittatum) 、E. pubigerum、高山淫羊藿( E. alpinum) 等11 个种的核型公式均为2n = 2x= 6m (2SAT ) + 6sm, 而黔岭淫羊藿( E. leptorrhizum) 的核型公式为2n = 2x = 8m ( 2SAT ) + 4sm。结果显示12 种淫羊藿的体细胞染色体数目均为2n = 12 , 基数X = 6; 都属于对称核型、都有1 对中间随体; 染色体均为m、sm 两种类型。     

柔毛淫羊藿及其近缘种叶片非腺毛形态及其分类学意义

柔毛淫羊藿(Epimedium pubescens Maxim.)是中国淫羊藿属植物中分布较为广泛、形态变异较为丰富的物种,柔毛淫羊藿及其近缘种在分类中存在诸多争议。为研究柔毛淫羊藿及其近缘种变异规律和进行种的界限划分,该研究对柔毛淫羊藿31个居群和近缘种星花羊藿3个居群、镇巴淫羊藿1个居群、万源淫羊藿1个居群共36个居群的叶背非腺毛进行了显微观察。结果显示：(1)所观察到的非腺毛分为直毛、曲毛、伏曲毛、长伏毛、拟短伏毛、短伏毛、单细胞毛7个大类19个小类,并发现每个居群或每个个体的叶背面非腺毛是由多种类型构成。(2)共观察到13个居群具有乳突,且69.2%非腺毛较少(非腺毛密度少于50个/mm²)的居群具有乳突;而且共有27个居群中具有单细胞毛,占该研究36个居群的75%。(3)以非腺毛密度、主要类型构成进行居群归类,其中柔毛淫羊藿21个居群为直毛群(A),柔毛淫羊藿7个居群为曲毛群(B),柔毛淫羊藿2个居群、星花淫羊藿3个居群、镇巴淫羊藿1个居群为长伏毛群(D),柔毛淫羊藿1个居群为拟短伏毛群(E),万源淫羊藿1个居群为短伏毛群(F),所有居群均共有直毛类非腺毛,说明直毛类非腺毛为柔毛淫羊藿及其近缘种的核心类型非腺毛。(4)从居群内非腺毛类型组成的角度梳理出了居群间的演化关系,直毛群：AⅠ→AⅡ→AⅢ→AⅣ→AⅤ;曲毛群：BⅠ→BⅡ→BⅢ→BⅣ;长伏毛群：DⅠ→DⅡ→DⅢ;直毛群→曲毛群;短直毛群→短伏毛特化群;短直毛群→拟短伏毛特化群,且居群间的演化关系与地理分布呈现良好的相关性。(5)单细胞毛为淫羊藿属中首次发现。研究认为,单细胞毛可能与主流非腺毛类型(直毛和曲毛)和地理分布有关,但乳突则与叶背面的非腺毛密度可能存在负相关关系;该研究结果支持将星花淫羊藿归为柔毛淫羊藿种下等级的分类处理。     

紫距淫羊藿的地理分布新记录及形态描述

淫羊藿属依据少量栽培个体命名的类群普遍存在,往往缺乏足够的野外调查和形态性状统计,对其性状变异幅度、变异式样和分类价值研究不够。紫距淫羊藿(Epimedium epsteinii)由Stearn于1997年依据引种个体命名,为掌握其资源分布及形态性状变异,该研究基于居群概念,对淫羊藿属分布区展开调查,在各分布区选择一个居群(30个体/居群)于花期进行形态观察、统计和描述。结果表明:紫距淫羊藿以往被认为狭域分布于湖南天平山,该研究调查发现广东省和湖北省均有分布,为新分布记录。此两处新分布分别位于天平山的南部和北部,将其自然分布区显著扩大。基于居群观测的形态变异较原描述更广泛。6个主要数量性状(株高、序轴长、小花数、叶长、叶宽和根茎)和花部颜色在居群间和个体间均呈现丰富的变异。生物种的分布范围并非完全连续,而是由若干个多少间断的居群组成,任何一个居群都存在不同程度的连续性变异,要更好地认识各物种,就应当足够重视这些居群系统。紫距淫羊藿的新分布记录对淫羊藿属的资源利用、扩散机制和系统地理学研究具有重要意义。     

淫羊藿属植物查耳酮合成酶启动子序列的克隆及比较分析

采用TAIL-PCR技术从箭叶淫羊藿(Epimedium sagittatum)叶片中克隆得到查耳酮合成酶基因(Chalcone synthase)的启动子,命名为ECHSP, 长度为750 bp,其具有TATA BOX、CAAT BOX、MYB结合位点、MYC结合位点等元件。对箭叶淫羊藿、木鱼坪淫羊藿(E. franchetii)、粗毛淫羊藿(E. acuminatum)、直距淫羊藿(E. mikinorii)、黔岭淫羊藿(E. leptorrhizum)等5种植物的CHS启动子序列进行比较分析,结果表明,CHS启动子的核苷酸多态性丰富,表明CHS 的表达可能受到多种因素的灵活调节。ECHSP与其他植物的CHS启动子序列进行比较,其TATA box的位置可能与黄酮类化合物的积累相关。此外,进化分析表明ECHSP的核苷酸序列可应用于淫羊藿属植物的系统进化研究。     

中国淫羊藿属(小檗科)二新种

报道了中国小檗科Berberidaceae淫羊藿属Epimedium两个新种,拟巫山淫羊藿Epimedium pseudowushanense B.L.Guo和青城山淫羊藿E.qingchengshanense G.Y.Zhong ＆ B.L.Guo。拟巫山淫羊藿产于贵州黔东南州和广西北部,一直因小叶片相似被误定为巫山淫羊藿Epimedium wushanense T.S.Ying,但二者花的结构极其不同。拟巫山淫羊藿以花瓣距细和瓣片有皱褶而与产于湖北的直距淫羊藿E.mikinorii Stearn相类似,但距较短,长仅10–15mm,瓣片小,小叶片狭卵形至披针形,叶背面被稀疏的白色长毛,具白粉,花瓣紫红色或紫色,内轮萼片宽卵形或卵形,可以区别。青城山淫羊藿局限分布于四川都江堰市青城山后山,该种为淫羊藿属雄蕊显著伸长的种类,与川鄂淫羊藿E.fargesii Franch.相似,但花各部较川鄂淫羊藿为小,花瓣瓣片大而圆,不裂,花丝紫色可以区别。     

箭叶淫羊藿同质园栽培居群非腺毛多样性及其分类学启示

淫羊藿是国际上多年来重点研究的药用植物.箭叶淫羊藿(Epimedium sagittatum)是淫羊藿属分布最广,也是形态变异最大的物种,箭叶淫羊藿复合群种分类中存在诸多疑点和争议.为了重建淫羊藿属的系统发育,我们利用数码显微摄影技术对10省16个箭叶淫羊藿同质园栽培居群的叶背非腺毛性状进行了比较研究.结果表明,箭叶淫羊藿非腺毛性状的主要特征包括:细胞数、非腺毛长度、是否存在伸长细胞、顶细胞形态及由此导致的顶细胞直径和壁厚差异.不同居群的非腺毛形态和特征存在巨大差异和丰富的多样性,其中项细胞形状是最重要的特征,并与全长、有无伸长细胞、项细胞比例、顶细胞直径和壁厚等多个性状密切关联.聚类分析将16个居群划分为两个类型,即梭形组和剑形组.变异式样的分析表明个体间和居群间整体呈现连续变异,丰富的多样性可能是多型种的表现.但形态上的分化往往来源于关键性状特征的强烈选择作用引起的居群间适应性分化,同质园栽培个体和居群间的形态差异暗示着适应性相关性状的遗传分化,居群间的形态差异应为地方适应性的结果,这种差异可能是物种形成的雏形.     

三种淫羊藿属植物的减数分裂研究

采用去壁低渗法对3种淫羊藿属(Epimedium)植物川鄂淫羊藿(E. fargesii Franch)、黔岭淫羊藿(E. leptorrhizum Stearn)和柔毛淫羊藿(E. pubescens Maxim)的花粉母细胞进行了减数分裂观察。结果显示,3种植物的染色体数目均为2n=12,减数分裂过程中染色体的构型和行为特征也非常相似,减数分裂过程基本正常。但也发现一些染色体的异常行为,如二价体的提前分离、染色体桥、姐妹染色单体提前分离、染色体断片和二次分裂不同步等异常现象。这些减数分裂过程中的染色体变异可能在一定度上推动了淫羊藿属植物的系统发育和物种形成。     

三种药用淫羊藿的地理分布与资源调查

淫羊藿属(Epimedium L.)植物为传统的中草药,也是新优地被观赏植物,具有悠久的药用历史和巨大的开发潜力.对3种重要的药用淫羊藿(朝鲜淫羊藿E.koreanum、心叶淫羊藿E.brevicornum和箭叶淫羊藿E.sagittatum)的地理分布、形态特征和资源现状进行了调查.调查发现,朝鲜淫羊藿分布于中国东北部,主要沿长白山脉分布,长期的过度采收使野生资源遭到严重破坏,保护工作迫在眉睫;心叶淫羊藿分布于西北各省以及山西、河南等省,野生资源丰富,但目前开发利用较少;箭叶淫羊藿广泛分布于华东、华南各省区,但野生资源蕴藏量并不丰富,且不同分布区形态变异较大,物种鉴定尚存诸多疑问.为保证野生资源的可持续利用,未来应控制朝鲜淫羊藿的过度采收,加强心叶淫羊藿的合理开发利用,不同地区的箭叶淫羊藿形态差异较大,质量不稳定,建议对其进行系统的质量评估之后择优开发利用.     

箭叶淫羊藿与近缘种天平山淫羊藿花粉形态对比研究

该研究采用扫描电子显微镜(SEM, scanning electron microscope)对箭叶淫羊藿13个居群(含箭叶淫羊藿光叶变种1个居群)、天平山淫羊藿7个居群进行花粉形态和外壁纹饰的观察及对比研究。结果表明:两个类群的花粉均为近球形,具三孔沟,大小相近。箭叶淫羊藿的花粉大小为(18.21～21.66)μm ×(19.55～23.63)μm, 天平山淫羊藿的花粉大小为(18.32～21.43)μm ×(19.73～23.48)μm。外壁纹饰是花粉形态的重要性状。不同居群间花粉外壁纹饰存在较大差异,主要分为网纹纹饰、条网纹纹饰和颗粒状纹饰三大类,继而根据网脊类型和网眼密度分为六亚类。其中,箭叶淫羊藿的花粉形态包含了全部的三大类六亚类,天平山淫羊藿包含其中的三大类四亚类。天平山淫羊藿花粉特征为箭叶淫羊藿花粉形态变异的子集。整体而言,外壁纹饰类型随纬度和海拔增加呈现出由网状纹饰向条网状纹饰过渡的趋势。花粉主要形态性状特征均与海拔存在密切相关性。在花粉形态及外壁纹饰特征上,天平山淫羊藿在箭叶淫羊藿变异范围之内,与其他宏观形态性状变异一致。花粉形态性状无法将两类群有效区分,未能提供天平山淫羊藿作为独立种的有力支撑。这暗示花粉形态证据在厘清近缘类群之间的系统发育关系意义相对有限,但能否对该属系统发育树大支的界定提供有力证据还有待于进一步研究。     

Morphological and ITS sequence divergence between taxa of Cuminia (Lamiaceae), an endemic genus of the Juan Fernandez Islands, Chile

Morphological and ITS sequence divergence were assessed between the two presently recognized taxa of the endemic genusCuminia (Lamiaceae), on Masatierra of the Juan Fernandez Islands. Morphological studies were based on leaf morphology of 51 individuals. Individuals ofC. fernandezia have narrow and lanceolate leaves with cuneate to acute bases and apices, whereas individuals ofC. eriantha have broadly ovate leaves with rounded bases and acute to obtuse apices. The two taxa can also be distinguished by the presence of pubescence.Cuminia eriantha has hairs on the leaves, young stems, floral peduncles, calyx, and corolla. Alternatively,C. fernandezia is glabrous except for tuft hairs on the nodes, and hairs on calyx teeth and corolla tubes. The ITS 1 and 2 regions of the five plants ofCuminia sequenced are a total of 451 bp long. All plants have identical ITS-1 but pubescent and glabrous plants are consistently different in ITS-2 sequence, revealing 1.3% total sequence divergence between the species. Both morphological and molecular data support the taxonomic recognition of two taxa, and the small but consistent differences appear to justify species status for the two entities. The pubescent populations representC. eriantha and the glabrous ones areC. fernandezia. It is hypothesized that the species diverged from a common ancestral immigrant to the islands, when Masatierra was much larger and more ecologically diverse than it now is. The two taxa seem to maintain their identities with no evidence of hybridization, even though they often grow in close proximity to one other on the island. Each population consists only of glabrous or pubescent plants, with no mixed population detected.     

A taxonomic revision of unifoliolate Chinese <Emphasis Type="Italic">Epimedium</Emphasis> L. (Berberidaceae)

Five Chinese species of Epimedium (Berberidaceae), E. simplicifolium T. S. Ying, E. baojingensis Q. L. Chen & B. M. Yang, E. zhushanense K. F. Wu & S. X. Qian, E. glandulosopilosum H. R. Liang and E. elachyphyllum Stearn are the only species of the genus previously described with unifoliolate leaves. Here, the authors review these five species based on extensive examination of specimens in herbaria and careful observation in the field and garden. E. simplicifolium is treated as a synonym of E. acuminatum Franch., and with the exception of E. elachyphyllum, the taxa are found to have predominantly trifoliolate and only occasionally unifoliolate leaves. Neotypes for E. zhushanense and E. glandulosopilosum are designated. In addition, we describe some characters of E. baojingensis, E. zhushanense, E. glandulosopilosum and E. elachyphyllum.     

Salvia tonaticensis (Lamiaceae), a rare new species from Mexico

Salvia tonaticensis is described and illustrated as a new species to science. It is known from the extreme southern portion of the Estado de Mexico and northern Guerrero, Mexico. It belongs to section Polystachyae; however, unlike the species of the section hitherto known, it possesses simple, bifurcate and trifurcate multicellular hairs on the stems, abaxial leaf surface, petioles, and inflorescence rachis. The flowers are also larger than those of other species of the section, and the calyces are densely tomentose with purple or white multicellular hairs that vary from simple to dendriform. Within the section this species shows some morphological similarities to S. connivens.     

假烟叶唇柱苣苔——中国广西石灰岩地区苦苣苔科一新种

报道了广西石灰岩地区苦苣苔科唇柱苣苔属(Chirita Buch.-Ham.ex D.Don)1新种--假烟叶唇柱苣苔(C.pseudoheterotricha T.J.Zhou.B.Pan & W.B.Xu).该种在叶型上与烟叶唇柱苣苔(C. heterotricha Merr.)较相近,但不同在于根状茎节间长2～8 mm,叶片和叶柄两面密被腺毛,侧脉3～4条,整个花序被开展的腺毛,花萼裂片披针形,花冠裂片长圆形,花丝在中部扭曲,密被紫色腺毛.     

革叶石豆兰——中国兰科植物一新记录种

报道了中国兰科新记录种——革叶石豆兰,它的主要特征是:无假鳞茎;叶小,出自根状茎的节上;总状花序短缩呈球形,具8-15朵密生的小花;花淡黄绿色,花瓣极小,唇瓣肉质,舌状。凭证标本保存在中国科学院植物研究所标本馆。     

药用钩藤和类钩藤的比较

本文首次从植物形态、种皮纹饰的扫描电镜观察,叶柄、茎组织构造、内部次生代谢产物-吲哚生物碱等方面对茜草科Rubiaceae,钩藤属Uncaria的钩藤Uncaria rhynchophylla (Miq.)Miq.ex Havil.与类钩藤Uncaria rhynchophylloides How进行了详细比较。认为类钩藤应是独立种,钩藤碱的含量在检测量之下,不能混入钩藤同样药用。     

Three new species of Mitrephora (Annonaceae) from Sabah, Malaysia

Three new species of Mitrephora (Blume) Hook. f. & Thomson, M. clemensiorum, M. vittata and M. woodii , are described from Sabah, Malaysia. Mitrephora clemensiorum is related to M. korthalsiana Miq., but is distinguished by having long inflorescences, long flowering and fruiting pedicels, and fruits with sessile monocarps. Mitrephora vittata is related to M. reflexa Merr., but has lanceolate, subcoriaceous leaves, and densely pubescent inflorescence rachides, flowering pedicels and bracts. Mitrephora woodii is similar to M. heyneana (Hook. f. & Thomson) Thwaites, but has smaller flowers and fruits with sessile monocarps     

七种中国淫羊藿属药用植物细胞分类学研究

该研究应用常规压片法对7种中国淫羊藿属药用植物进行了核型分析,为淫羊藿属药用植物的分类及选育等提供理论基础。结果表明：7种淫羊藿属植物体细胞染色体数目均为2n＝2x＝12,基数x＝6;水城淫羊藿、腺毛淫羊藿、保靖淫羊藿、拟巫山淫羊藿、天全淫羊藿5个种均有4对m染色体和2对sm染色体,核型公式均为2n＝2x＝12＝8m(2SAT)＋4sm,其中水城淫羊藿、腺毛淫羊藿的核型分析为首次报道;镇坪淫羊藿、偏斜淫羊藿具有3对m染色体和3对sm染色体,核型公式为2n＝2x＝12＝6m(2SAT)＋6sm。拟巫山淫羊藿第2对染色体具随体,其余物种第1对染色体均有随体;腺毛淫羊藿、保靖淫羊藿、拟巫山淫羊藿、镇坪淫羊藿、偏斜淫羊藿、天全淫羊藿均属于Stebbins 2A类型,水城淫羊藿为Stebbins 1A类型。结合文献综合分析发现,该属植物不同种间的核型高度一致,核型稳定,种间核型差异小,核型结构与地理分布、形态特征相关性较小。因此,淫羊藿属是一个在核型进化上较为保守的植物类群,用核型分析对该属植物属下进行种类鉴定、遗传演化十分困难,即使是属内远缘物种,其核型系统学的意义有限,但在属上的分类级别有较大的参考价值。     

Effect of plant population on ear differentiation and growth in maize

Maize was grown at 2.47, 3.70 and 4.94 plants m^-2. Ears were apparently initiated about 2 days later in the densest than in the least dense population, but rate of formation and final number of female floret primordia per row of the ear were similar in the two populations. In the densest population fewer primordia produced fully developed florets than in the least dense population and of those that were produced fewer extruded silks before pollen shedding ceased. Relative growth rates of dry mass and of length of the ear before flowering were unaffected by density, but with the apparent later start of ear growth in the densest population ears were lighter and shorter than in the least dense population. Number of florets per row of the ear at the time of flowering decreased slightly with increase in population. Number of kernels per row decreased with time after flowering, especially in the densest population. At final harvest size and mass per kernel, number of kernels per ear, length and circumference of the rachis, and space per kernel on the rachis all decreased with increase in population. Thinning the intermediate population at various times from shortly before flowering until near final harvest increased mass of grain and shoot, and number of kernels of the remaining plants at final harvest. The extent of the increases decreased progressively the later the thinning. Mass and volume per kernel were increased by thinnings done up to the time of flowering, but were unaffected by thinning from c. 16 days after flowering.