【作者】 常朝阳；

【导师】 石福臣；

【作者基本信息】 东北林业大学 ， 植物学， 2008， 博士

【摘要】 本文通过野外标本采集、国内各大标本馆近万份标本查阅,以及解剖学、微观形态学、体细胞染色体核型分析等方法,对中国锦鸡儿属植物进行了详细研究,旨在对国产锦鸡儿属植物的系统分类进行修订,并探讨一些种的分类学问题。主要结果如下:1.在2003-2004年对中国西北干旱区的锦鸡儿属植物进行了野外考察,共采集锦鸡儿属标本70号230余份,发现新种1个,采集到《中国植物志》遗漏的2个种,在查阅文献和对国内各大标本馆标本进行研究后,整理新变种和新组合变种各一个,新异名16个,订正了一些种的地理分布。新种为青河锦鸡儿(C.qingheensis Z.Y.Chang,L.R.Xu & F.C.Shi),新变种狭叶甘蒙锦鸡儿(C.opulens Kom.var.angustifolia Y.Z.Zhao exZ.Y.Chang & F.C.Shi),组合新变种粗刺锦鸡儿(C.franchetiana Kom.var.crassispina(Marq.)Z.Y.Chang & F.C.Shi),《中国植物志》遗漏种草地锦鸡儿(C.pumila Pojark.)和阿尔泰锦鸡儿(C.altaica Pojark.)。2.对叶片的解剖学研究认为叶片解剖结构是长期适应环境的结果,解剖结构与生境的相关性,也可能出现与亲缘关系的耦合,反映一定的系统相关性。而叶表皮微观形态特征,则被认为具有一定的分类和系统学意义。锦鸡儿属的植物叶表大都被覆一层蜡质,角质层不太明显,蜡质又可分为颗粒状(granules)、片状(flakelets)或块状(platelets),有时是片状和块状二者的结合,在不同种间有差别。毛状体的类型可分为3种:1.管形丝状毛(cylindrical-filiform hair),一般细长、直或稍弯曲;2.管状毛(cylindrical hair),一般外观稍短、粗壮,直或弯曲;3.带状毛(flattened ribbon-likehair),稍宽而扁,呈披针形(直)或带状(弯曲)。毛上面的纹饰可为单纯的条纹状,也有一些种类表皮毛上具有乳状(papillose)突起,其间为条纹状(striae)纹饰,这些特征与进化性状相关。气孔特征在锦鸡儿属中比较一致,均为无规则形气孔,气孔外拱盖光滑或具蜡质颗粒,下陷或与表皮细胞在同一平面。但气孔的分布式样则具有重要的系统学意义,可作为组下划分系的标准。3.核型研究表明,锦鸡儿属的核型一般比较对称,核型上的特化往往与其形态上的特化相关联,但也有例外。从倍性水平上来看,二倍体类群多是一些羽状叶的种,在分布上倾向于亚洲东部其祖先分布区,而四倍体的种类多是一些假掌状叶的类群,分布于西部干旱生境中,在形态上也表现的较为特化。这也符合锦鸡儿属的演化趋势。4.国产64种锦鸡儿大致可划分为5个分布区类型,即东亚分布型、蒙新荒漠分布型、青藏高原分布型、中亚分布型、间断分布型。特有现象明显,具有3个特有分布中心,即秦岭—华北特有中心、青藏高原特有中心和蒙新荒漠特有中心。在特有分布中,既有古特有种,也有新特有种。替代现象明显,在本属的演化过程中起着重要作用。5.根据本属植物的叶片是两面具气孔,还是仅下表皮具气孔,对中国锦鸡儿属的分类系统进行了调整,将国产锦鸡儿属植物分为6组、14系,使组、系的划分和种的归类更趋于合理。将北京锦鸡儿(C.pekinensis)和五台锦鸡儿(C.potaninii)从小叶系划分出来,并入树锦鸡儿系,将秦晋锦鸡儿并入柄荚系,将新疆锦鸡儿(C.turkestanica)并入刺叶系(Ser.Occidentales),同时将红花锦鸡儿、毛掌叶锦鸡儿、秦岭锦鸡儿作为一个系——红花系(Ser.Roseae),与由锦鸡儿和乌苏里锦鸡儿组成的锦鸡儿系(Ser.chamlagu)共同组成锦鸡儿组(Sect.Chamlagu),反映了系统演化上的特点。这个组的演化与以中亚为分布中心的灌木组(Sect.Frutescetes)是截然不同的,处于两个不同的进化分枝。更多还原

【Abstract】 In this paper we mainly deal with the taxonomy of the genus Caragana Fabr.from China. At the basis of examining great amount of specimen materials from the majority of Chinese herbaria,and of field collecting in the desert area of Northwestern China,combined with some experimental methods,such as leaf anatomy,epidermal features of leaflet under LE and SEM, and karyological study of some species,we have reviewed the taxonomy and systematics of Chinese Caragana,in order to clarify some taxonomical and evolutionary problems existing in this genus.The main results are as follows:1.From 2003 to 2004 we carried out two expeditions over desert areas of Northwesten China,and collected more than 230 sheets of Caragana specimens which stand for 70 populations,and in identifying them we found one new species to science,C.qingheensis Z.Y. Chang,L.R.Xu & F.C.Shi.In the process of examining herbarium material,two more varieties have been discovered or combined,these are C.opulens Kom.var.angustifolia Y.Z. Zhao ex Z.Y.Chang & F.C.Shi and C.franchetiana Kom.var.crassispina(Marq.) Z.Y. Chang & F.C.Shi.C.pumila Pojark.and C.altaica(Kom.) Pojark.were also collected and identified from Northwestern China near border area with Kazakhstan for the first one and in desert area near Altai region for the second one,which had been overlooked by authors of "Flora of China"(Chinese version).Another 16 names were also reduced to synonyms in this paper.2.The leaflet anatomical structure in Caragana species seems to be results of long adaptation to its environment,which may be coupling with affinities.However,micromorphology of leaf epidermis was of taxonomic and systematic significance.The common epicuticular wax layer was thick and in the form of flakelets and the flakelets generally were digitate edged,or may be platelets in sometimes,or granules in sparse.The type of granule wax was mostly on abaxial surfaces,while thick flakelet wax occurred on both sides.More often the flakelet and the platelet waxes were together to form a thick layer.Most species in this genus were covered with hairs.Morphologically the hairs can be three types,cylindricalfiliform, which was slender and slightly sinuous,and cylindrical one,which was shorter than the former and straighter.The flattened ribbon-like hairs also occur,which were flat and lanceolate,straight or waved.On the surface of hairs,tow kinds of ornamentations often occurred,that is,striate,and striate with papillae,which may bear some evolutionary clues of the genus.The stomata were present on both surfaces in some species,but in others were seen only on the abaxial surface,except for C.bicolor and C.franchetiana,in which the stomata very interestingly occurred only on the adaxial surface.Only anomocytic stomata were seen in the genus,with outer stomatal rims smmoth or sinuous.and dentate.3.The karyotype of chromosomes in Caragana was not so much differentiated,and if differentiated it always followed by some morphological characters.The diploid and tetraploid are the main ploidy level of this genus,with 2n=16(diploid) or 2n=32(tetraploid).Triploid was found only in(sinica,and hexaploid was seen only in C.ussuriensis.Those species with diploid chromosomes mostly are pinnate-leaved,and mainly distributed in Estern Asia where probably being its ancestral area.but those species with tetraploid chromosomes are majorly with digitate leaflets,and more inclined to adaptive to desert areas in Northwestern China.4.As to the distributional pattern of Chinese Caragana,5 areal types could be grouped for the whole 64 species,namely Eastern Asian areal type,Mongolia-Xinjiang desert areal type, Qinghai-Xizang Plateau areal type,Middle Asia areal type and Disjunct areal type.Endemicity is also an important character for Caragana species,especially in China,nearly half of its total species are endemic.There are three endemicity centers for Chinese Caragana,i.e.Qinling Mt. and North China endemicity center,Qinghai-Xizang Plateau endemicity center and Mogolia-Xinjiang desert endemicity center.In Qinling Mr.and North China center,paleo-endemic species more often present,while in Mogolia-Xinjiang desert center,neo-endemic species more often occurred.In addition,vicarious distribution was common in the genus,and vicariance perhaps was very important in the speciation of the genus.5.According to the stomata distribution pattern,an adjusted scheme of infrageneric classification for Chinese Caragana was given,based mainly on Zhou Daowei(2005) and others,by occurrence of amphistomatic or hypostomatic leaf epidermis.Here 6 sections and 14 series were proposed for 64 species of Chinese Caragana.更多还原