【作者】 刘仁林；

【导师】 杜天真；

【作者基本信息】 江西农业大学 ， 森林培育， 2007， 博士

【摘要】 杜鹃属Rhododendron L.全球约1000种,是典型的北温带分布区类型。随着许多新种的发现和先进技术在分类上的应用,这个属的分类问题也日益突出。本文以形态分类为主线,在查阅相关模式标本、非模式标本的基础上,选取在分类上具有重要价值和存在争议的种类,到模式标本产地取样,应用现代分子标记技术、导管形态和叶解剖技术以取得相关的证据,对中国映山红亚属Subgenus Tsutsusi (Sweet) Pojarkova的系统分类进行综合分析,得到如下结论:1.本文基于ITS序列分析、维管束导管形态分析和叶解剖结构分析等证据,中国映山红亚属有74种2个亚种13个变种和1个变型;其中映山红组有69种2亚种和12个变种,轮叶组有5种1变种和1个变型。此外,本文提出了一个映山红亚属系统排列。2.依据ITS分析,映山红亚属应该划分为2个组,即映山红组Sect.Tsutsusi Sweet和轮叶组Sect.Brachycalyx Sweet。3.根据ITS分析,大武杜鹃Rhododendron tashiroi Maxim.应该放在轮叶组Sect.Brachycalyx Sweet比较合适。4.ITS分析表示,大字杜鹃Rhododendron schlippenbachii Maxim.没有与映山红亚属聚在同一个分支上,因此它可能有独立的系统地位,需要进一步研究。5.根据ITS分析、导管形态分析、叶解剖结构分析和表形形态分析,灰齿杜鹃Rhododendron cinereoserratum Tam、戴云山杜鹃Rhododendron daiyunicum Tam不能独立成为一个种,本文研究认为应该把戴云山杜鹃作为满山红的变种处理比较合适,把灰齿杜鹃处理为满山红的异名;保留白花满山红Rhododendron mariesii Hemsl.et Wils.f.albescense B.Y. Ding et G .R.Chen在发表的原文中作满山红的变型;。因此中国映山红亚属轮叶组目前应包括5个种和1个变种、1个变型。此外,本文研究认为天堂杜鹃Rhododendron tiantangense G .Z .Li是亮毛杜鹃Rhododendron microphyton Franch的新组合;同时把棒柱杜鹃Rhododendron crassimedium Tam处理为背绒杜鹃Rhododendron hypoblematosum Tam的异名;把茶绒杜鹃Rhododendron rufulum Tam处理为龙岩杜鹃Rhododendron florulentum Tam的异名。6.通过对映山红亚属的区系分析,中国映山红亚属的种数最多,占该亚属种类的69%,是映山亚属的多样化中心,也是映山红组的多样化中心;但日本是轮叶组的多样化中心,因为中国仅有5种1个变种和1个变型,日本达19种。在中国大陆映山红亚属的种数依次是广西>广东>湖南>江西>贵州>福建>四川、云南,其中主要分布在广东、广西、湖南、江西这4省区。映山红亚属的物种多样化中心在广西-广东-湖南南部。映山红亚属可能由耳叶杜鹃亚组最近的祖先类群演化过来,因此在这个亚属中较原始的类群可能是具刚毛、腺毛的5枚雄蕊类群。这些类群主要分布在广西、广东及湖南南部,因此广西、广东及湖南南部既是映山红亚属的起源中心和物种多样性中心。7.轮叶组的类群可能直接由映山红组的一些原始类群演化而来,前者在获得的新性状后以较快的速率进化,与映山红组形成姐妹群,说明这两个组有较密切的亲缘关系。8.映山红亚属在我国广西-广东-湖南南部起源之后,由如下途径向东南、东北部地区散布:起源地→马来西亚诸岛屿→菲律宾;中国大陆→日本;中国大陆→台湾。9.新的发现(1)上犹杜鹃新变种Rhododendron seniavinii Maxim. var. Rhododendron shangyounicum R .L. Liu et T. Z.Du,var. nov.(2)在粗柱杜鹃的叶解剖结构中下表皮的上方,发现有一层可能由海绵组织细胞异化为“棉花状”的细胞,这种细胞的名称和功能需要进一步讨论。(3)在研究中发现,毛果杜鹃、南昆杜鹃、溪畔杜鹃存在“拟穿孔板”(暂时命名),其名称、功能和起源需要进一步研究。更多还原

【Abstract】 As it is well known , the genus Rhododendron L. is a large one with the number of 1000 species in the world, it is considered as a type of temperate distribution .Since the genus Rhododendron had been established by Linnaeus in 1753,much has been written on the classification of this genus.Because of the collection being in an ever-increasing stream from any place in the world, particularly from China ,more and more new species of Rhododendron have been named ,and at the same time ,problems of systematic classification of Rhododendron are occurring. At the same time,there are same problems occurring in the Subgenus Tsutsusi (Sweet) Pojarkova,for example, some species newly named from China in the recent of 30 years are difficult to be divided ,and whether sect.Brachycalyx Sweet includes Rhododendron tashiroi Maxim. etc. The question now arises: are we to accept the present classification or are we to substitute some other classification in its place? In order to make a clear classification for the subgenus Tsutsusi,a thorough study and a detailed examination of the subgenus Tsutsusi has been made in this paper based on the analysis of ITS sequences ,features of leaf anatomic structure ,features of vessels and characters of morphology.With modern technique of cassification such as molecular marker and plant anatomy,a study on the systematic classification of subgenus Tsutsus of Rhododend -ron in China is made in this paper, in which 74 species and 2 subspecies and 13 varieties and 1 form belonging to this subgenus have been discussed with the conclusions as follows:1.Based on various evidences from the analysis of ITS , features of leaf anatomic structure ,features of vessels and characters of morphology in this paper , Subgenus Tsutsusi (Sweet) Pojarkova of Rhododendro has 74species and 2subspecies and 13 varieties and 1 form in China ; Sect.Tsutsusi Sweet of this subgenus has 69species and2 subspecies and 12 varieties ; Sect.Brachycalyx Sweet of this subgenus has now 5 species and 1 variety and 1 form . In addition , a new arrangement of systemic classification of this subgenus has been offered in this paper.2.Based on ananlysis of ITS,it is considered to be correct that the Subgenus Tsutsusi (Sweet) Pojarkova of Rhododendron is classified into two sections ,namely section Tsutsusi Sweet and section Brachycalyx Sweet.The Sect.Tsutsusi Sweet and Sect.Brachycalyx Sweet are sister groups belonging to Subgenus Tsutsusi (Sweet) Pojarkova. 3.It is right that Rhododendron tashiroi Maxim. is placed in Sect.Brachycalyx Sweet according to the ananlysis of ITS.4. Based on ananlysis of ITS ,the systematic position of Rhododendron schlippenbachii Maxim. is in need of further discussion because of its position shown in the phyletic tree in which it has not clustered with Subgenus Tsutsusi .5.Based on various evidences from the analysis of ITS,features of leaf anatomic structure ,features of vessels and characters of morphology,it is considered to be right that species Rhododendron daiyunicum Tam is treated as a variety of species Rhododendron mariesii Hemsl. et Wils.and and Rhododendron mariesii Hemsl. et Wils. f. albescense B.Y.Ding et G . R.Chen published in 1989 is retained as a form of Rhododendron mariesii Hemsl. et Wils.; Species Rhododendron cinereoserratum is a synonym of Rhododendron mariesii Hemsl. et Wils.; therefore the Sect.Brachycalyx Sweet has now 4 species and 1 variety and 1 form in China .Species Rhododendron tiantangense G .Z .Li is a new combination of Rhododen -dron microphyton Franch ; Rhododendron crassimedium Tam is treated as a synonym of Rhododendron hypoblematosum Tam and Rhododendron rufulum Tam is a synonym of Rhododendron florulentum Tam6.Based on the analysis of the flora of subgenus Tsutsusi Sweet in this paper , some important conclusions have been obtained as follows: China is the center of species diversity of subgenus Tsutsusi and of Sect.Tsutsusi ; but Japan is the center of species diversity of section Brachycalyx .Most of species of subgenus Tsutsusi distribute in China , the number of species of this subgenus is in order as Guangxi> Guangdong>Hunan>Jiangxi>Gui Zhou>Fujian>Sichuan or Yunnan . It is sure that the combination region in Guangxi and Guangdong and Hunan is the center of species diversity of subgenus Tsutsusi in the world .The subgenus Tsutsusi origins from the combination region in Guangxi and Guangdong and Hunan in China , it evolutes directly from the primitive group of subsect. Auriculata .7.Based on the analysis of ITS and paleogeography and fig.XIV , Sect. Brachyca -lyx Sweet probably evolutes from the primitive group of Sect.Tsutsus.Sweet , it evolutes quickly with new characters and form a sister group with Sect.Tsutsus.Sweet which show close connection between these two sections .8.The routes of emigration of Subgenus Tsutsusi (Sweet) Pojarkova coming from its original region are considered as follows : southern and western part of China→ islands of Malaysia→northern part of Philippine ; southern and western part of China→Japan ; mainland of China→Taiwan.9.Discovery(1) A new variety of species : Rhododendron seniavinii Maxim. var. Rhododen -dron shangyounicum R .L. Liu et T. Z.Du,var. nov.(2) A type of idio-cells which is similar to the“cotton”has been found in mesophyll tissue of Rhododendron crassistylum M.Y.He and it is named as“cotton”cell in this paper. It is necessary to discuss what is the function of this type of cells .(3) A special type of pits named“perforation-like plates”is found in the vessels of species Rhododendron rivulare Hand. -Mazz. and Rhododendron . naamkwanense Merr.and Rhododendron.seniavinii Maxim.,it is valuable in evolution and in Classification of Rhododendron , its function and origin is in need to further research .更多还原