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1.
Xizangia bartschioides (Hand.-Mazz.) D. Y. Hong——玄参科一新组合   总被引:1,自引:0,他引:1  
虽然玄参科的马松蒿Xizangia serrata D.Y.Hong与齿叶翅茎草Petrygiella artschioides Hand.-Mazz.系同物异名,但齿叶翅茎草与翅茎草属其余4种植物在习性、叶、花萼等外部形态上有显著差异,在种皮方面的差异尤为突出。马松蒿属Xizangia 作为属的地位是合适的。因此,本文作了一个新组合,即XI-zangia bartschioides(Hand.-Mazz.)D.Y.Hong,而把Ptertrygiella bartschioides Hand.-Mazz.和Xizangia serrata D.Y. Hong均作异名处理。  相似文献   

2.
中国一些植物名称的修正   总被引:3,自引:1,他引:2  
本文认为黄花长蕊草Changruicaoia flaviflora Z.Y.Zhu应是尖齿异野芝麻Helerolamium debile(Hemsl.)C.Y.Wuvar.tochauese(Kudo)C.Y.Wu的异名,Xizangia bartschioides(Hand,-Mazz.)D.Y.Hong为一晚出同名应予废弃,川八角莲的正确名称应是Dysosma delavayi(Fanch.)Hu。  相似文献   

3.
孔药花属(鸭跖草科)的核型研究   总被引:2,自引:0,他引:2  
本文首次对鸭跖草科孔药花属Porandra Hong进行染色体研究。孔药花P.ramosa Hong和攀缘孔药花P.scandens Hong在染色体的大小、数目和形态上都十分相似,核型公式为2n=36=4m+26sm+6st(2sat),核型类型属于3B。染色体证据支持孔药花属与穿鞘花属Amischotolype和Coleotrype属相近的观点。  相似文献   

4.
鄂尔多斯草地退化过程中植被地上生物量空间分布的异质性   总被引:14,自引:0,他引:14  
程晓莉  安树青  钦佩  刘世荣 《生态学报》2003,23(8):1526-1532
应用地统计学方法分析研究了鄂尔多斯草地荒漠化过程中植被地上生物量空间分布的异质性。发现从本氏针茅(Stipa bungeana)、本氏针茅 油蒿(Artemisia ordosicn)、油蒿、油蒿 牛心朴子(cynanchum komarovii)、牛心朴子群落的5个退化系列群落中,植被地上生物量空间格局异质化程度及其相关范围变化非常明显。变异函数的基台值(C0 C)在5个退化群落中的变化表明,在本氏针茅群落中,植被地上生物量空间分布异质性较低(0.48),本氏针茅 油蒿群落增强(19.47),油蒿群落显著增强(1522),油蒿 牛心朴子群落减弱(171.6),牛心朴子群落显著减弱(4.164)。变异函数的相关范围(A0)表明,在本氏针茅群落空间相关范围较小(53.9cm),本氏针茅 油蒿群落增加(77.8cm),油蒿群落减小(51.7cm),油蒿 牛心朴子群落增加(62.9cm),牛心朴子群落增加(94.6cm)。空间变异比分析表明,由空间自相关因素引起的空间异质性占主要部分(74.2%~80.7%)。空间分布格局图(Kriging map)分析进一步显示,退化群落中植被地上生物量格局变化显著。从本氏针茅群落退化到油蒿群落的中度荒漠化过程中,植被地上生物量空间分布的异质性的增强。由油蒿群落退化到牛心朴子群落的严重荒漠化过程中,植被地上生物量空间分布的异质性减弱。  相似文献   

5.
报道了东北蒿属龙蒿组10个各植物的核型。核型公式分别为:龙蒿(Artemisia dracunculus.L.)(2n)=4x=36=28m+8sm;猪毛蒿(A.scoparia Waldst.et Kit.(2n)=2x=16=12m+4sm;盐蒿(A.halodendron Turcz.ex Bess.)(2n)=4x=36=30m+4sm+2st;光沙蒿(A.oxycephala Kitag  相似文献   

6.
本文报道了我国蒿属6种的染色体核型,它们的核型公式分别为:牡蒿(ArtemisiajaponicaThunb.)2n=18=12m+6sm(2SAT);西南牡蒿(A.parvifloraBucb.-Ham.exRoxb.)2n=36=30m+4sm+2st(6SAT);多花蒿(A.myrianthaWall.exBess.)2n=36=30m+6sm:牛尾蒿(A.dubiaWall.exBess.)2n=36=28m+8sm(2SAT);野艾蒿(A.lavandulaefoliaDC.)2n=54=42m+12sm;荚毛蒿(A.velutinaPamp.)2n=54=36m+18sm.  相似文献   

7.
滇西北马先蒿属传粉生物学的初步研究   总被引:9,自引:0,他引:9  
对云南西北部的中甸和德钦高山地区4种马先蒿属(PedicularisL.)植物的传粉生物学进行了观察。晚夏开花的马先蒿与传粉熊蜂(BombusLatr.)的出现在物候上有一定的相关性。其中短管、无喙、无蜜腺的肉根马先蒿(P.royleiMaxim.)和茨口马先蒿(P.tsekouensisBonati)是由熊蜂工蜂震动花粉、背触式传粉,这与其花冠类型的较原始性有关;长管、具喙、无蜜腺的斑唇马先蒿(P.longifloravar.tubiformis(Klotz.)Tsoong)和云南长管马先蒿(P.siphonanthaDon.var.delavayi(Franch.)Tsoong)通过熊蜂工蜂震动花粉、腹触式传粉。长管类马先蒿在植株相对矮小的情况下,通过较长的花冠管具喙向外伸出以实现授粉,这可能是与其传粉熊蜂协同进化的结果。  相似文献   

8.
<正>Dear Editor,Scylla serrata reovirus(SsRV),first discovered in China in 2004,is now known to be widespread in the mud crab(Scylla serrata)farming pond of China.(Chen et al.,2008).Since there are no effective treatments currently available for this viral pathogen,early diagnosis is the  相似文献   

9.
此文包括了缢花沙参Adenophora contracta (Kitag.) J. Z. Qu et Hong 和松叶沙参 A.pinifolia Kitag.两个种。在过去,前者曾被处理为石沙参的变种(A.polyantha Nakai var.contracta Kitag.)。本文通过对它的地理分布、植物体形态和细胞学特征的研究,发现它相当独特。所以,把它处理为种的等级A.contracta (Kitag.) J.Z.Qu. et Hong。后者,曾被洪德元(1983)处理为存疑种。在此被确认为独立的种。  相似文献   

10.
陕北撂荒地上优势蒿类叶片解剖结构及其生态适应性   总被引:5,自引:0,他引:5  
杨超  梁宗锁 《生态学报》2008,28(10):4732-4738
对陕北丘陵区撂荒地上处于自然恢复演替不同时期的3种优势种蒿类铁杆蒿(Artemisia gmelinii Web.)、茭蒿(Artemisia giraldii Pamp.)、猪毛蒿(Artemisia scoparia)的叶片解剖结构进行了观察研究的结果表明,随着演替序列的发展,3种蒿类的栅栏组织随演替时间的推移呈现出全栅型-环栅型-过渡型的趋势,叶片解剖结构说明越靠近演替前期的蒿类对干旱的适应性越强。此外,3种蒿类的栅栏组织排列都很紧密,表皮细胞排列不规则,且具有表皮毛和腺毛等旱生适应结构;在猪毛蒿和茭蒿中还发现了特化的气腔结构。这些特征均能说明这些蒿类植物具有很好的抗旱适应性,作为环境改造的先锋物种,它们在当地的自然植被恢复演替中起着积极的正向推动作用。  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

18.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

19.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

20.
For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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