Study of Netural Tritetpenes Components on Trunk of Cathaya argyrophylla Chun et Kuang Native to China

A prelimimary investigation on neutral triterpene components of Cathaya argyrophylla Chun et Kuang trunk is reported. Seven crystalline components had been isolated from trunk of C. argyrophylla, six of them had been identified as known serratene famlly components: Cathaya B (3α-methoxy-21-keto serratene). Cathaya C [serratenediol monoaeetate (3β-acetyl-21a-hydroxy-△14-serratene)], Cathaya D (serratenedio), Cathaya E (compound [D]), Cathaya F (3β-hydroxy-21-keto-△14-serratene) and cathaya G (serratenedione). Cathaya H seems to be a new serratene family component. Its structure will be studied further.     

On serratene components in relation to the systematic position of Cathaya (Pinaceae)

Abstract The genus Cathaya discovered in Kwangsi, Sichuan, Hunan and Guizhou is endemic in China. Only one species (C. argyrophylla Chun et Kuang) has so far been known in the genus. The question on it’s systematic position in the family Pinaceae has been much debated. However, according to some taxonomists and morphologists, this genus is related to genera Pinus, Picea and Pseudotsuga of the Pinaceae. No phytochemical data, especially of serratene components on Cathaya have been recorded. This paper deals with the systematic position of Cathaya in Pinaceae based on seven known components of serratene family which are isolated from the trunk of Cathaya argyrophyua growing in Sichuan. A comparative study on serratene components of Cathaya with other genera ofPinaceae showed that Cathaya is related to genera Pinus and Picea.     

珍稀植物银杉的种子萌发特性

银杉(Cathaya argyrophylla)为我国特有珍稀古生树种,其种群自然更新困难,被列为国家Ⅰ级重点保护植物。由于银杉种子自然发芽率低,对其种子萌发过程的生理生态特性进行研究显得十分必要。对银杉种子的千粒重、含水率等物理特性及不同保存方法对种子生理活性影响进行了研究,重点研究了银杉种子经激素处理后其发芽率的变化趋势以及不同贮藏方法对种子萌发率以及抗氧化酶系统活性的影响。结果表明:储存时的水分条件是保证生活力的关键,失水带来的逆境胁迫导致银杉种子抗氧化酶活性变化剧烈,长时间的胁迫(报纸储存90d)造成种子能量消耗严重,抗氧化酶活性下降剧烈,导致发芽率极低(2.50%);用苔藓包裹低温贮藏的方法对种子活力影响最小,种子的发芽率最高,且能较长时间的保存。用不同激素处理后,能对种子的发芽有一定的促进作用,其中以IAA表现最好,特别是100mg/L浓度的IAA能提高种子发芽率30.30%,效果明显,但随着贮藏时间的延长,由于银杉种子自身活力丧失迅速,激素浸泡处理效果并不显著。     

银杉引种栽培的研究

本文报道我国特有珍贵植物——银杉的生长环境、植物学特性及引种栽培的研究结果,为保护、发展和利用这一珍贵植物资源提供科学依据和技术措施。     

A Preliminary Study on the Population of Cathaya argyrophylla in Bamianshan Mountain

Cathaya argyrophylla Chun et Kuang is a China endemic and endangered evergreen conifer, listed in the Red Data Book of plant in China, with less than 5000 individuals remaining on earth. The age structure of C. argyrophylla population in Bamianshan Mountain showed its stability, but was different among metapopulations, especially in the aged Cathaya forests there often appeared a lack of generation continuety. Though the aboveground biomass of the population varied from 30000 kg · ha-1 to 110000 kg · ha-1 with different metapopulations, the increment of the biomass had no significant difference among metapopulations but could basically reflect the productivity of this population in that area. Its distribution patterns were mainly contagious, even when the shrub cover was very high and random in young Cathaya stands.     

Formation of Mycorrhiza-like Structures in Cultured Root/Callus of Cathaya argyrophylla Chun et Kuang Infected with the Ectomycorrhizal Fungus

An in vitro system was used for ectomycorrhizal synthesis of Cenococcum geophilum Fr. with Cathaya argyrophylla Chun et Kuang, an endangered species. Calli initiated from stem segments and adventitious roots differentiated from young seedlings were removed and cocultured with Cenococcum geophilum on a modified Murashige-Skoog medium. Fungal hyphae were visible within intercellular spaces of the callus 4 weeks after inoculation, but definite and well-developed Hartig net structures did not form in the calli 8 weeks after inoculation. The typical ectomycorrhizal structures (i.e. hyphal mantle and intracortical Hartig net) were observed in root segments 8 weeks after inoculation. This is the first report of aseptic ectomycorrhizal-like formation/infection between root organ/callus of Cathaya argyrophylla and the ectomycorrhizal fungus Cenococcum geophilum. This culture system is useful for further investigation of mycorrhizal synthesis in Cathaya trees.（Author for correspondence. Tel: +86 (0)451 8219 1783; Fax: +86 (0)451 8219 1795; E-mail: lumin-fu@163.com）     

Formation of Mycorrhiza-like Structures in Cultured Root/Callus of Cathaya argyrophylla Chun et Kuang Infected with the Ectomycorrhizal Fungus Cenococcum geophilum Fr.

An in vitro system was used for ectomycorrhizal synthesis of Cenococcum geophilum Fr. with Cathaya argyrophylla Chun et Kuang, an endangered species. Calli initiated from stem segments and adventitious roots differentiated from young seedlings were removed and cocultured with Cenococcum geophllum on a modified Murashlge-Skoog medium. Fungal hyphae were visible within intercellular spaces of the callus 4 weeks after inoculation, but definite and well-developed Hartig net structures did not form in the calU 8 weeks after inoculation. The typical ectomycorrhizal structures （i.e. hyphal mantle and Intracortical Hartig net） were observed in root segments 8 weeks after inoculation. This is the first report of aseptic ectomycorrhlzal-like formation/infection between root organ/callus of Cathaya argyrophylla and the ectomycorrhizal fungus Cenococcum geophflum. This culture system is useful for further investigation of mycorrhizal synthesis in Cathaya trees.     

A Scanning Electron Microscopic Observations of the Leaves in Some Conifers

Scanning electron microscopic observations of the leaves in some conifers are described. These are hyplocheilie stomata surrounded by different morphological subsidiary cells. In Keteleeria, the lateral wall of larger subsidiary cells possesses prom.inant eutieular globoides. Cuticular semigloboides between the sinuoms epidermal anticlinal walls are most obvious in other epidermis. However the single laver of cushion cells which looated underneath the guard ceils of the abaxial epidermis in Cathaya is discovered. The mesophyll ceils with incurved walls of Cathaya consist mainly of single layer of flat oubical cells flat longi-cubieal cells as of the polytriehaeeous lamcllae, thus it may be designated as mesolamellae. It not only supports the establishment of Cathaya Chun and Kuang as a new genus of the Pinaeeae but also may be another important biosystematical evidence between Cathaya and Pinus. The distribution and polymorphism of foliar solereids in Amentotaxus which are different from leaves of other gymnosperms described. The transfusion tracheids are also different in some ways from other genera.     

松科系统学研究(Ⅰ)

松科的系统发育研究历来已久,但由于性状进化的不同步性和属间进化缺少中间环节,致使科的分类系统和各属之间的演化关系至今未得到令人满意的解决。本文在钻研已有文献的基础上,筛选出松科属间综合分类性状36个,有序进化性状20个,借助计算机,以属为分类单位,进行表征分析研究确定松科分类系统,结果将松科分为三个亚科:松亚科Subfam.Pinoideae:仅Pinus Linn;落叶松亚科Subfam.Laricoideae Melchior & Werderm.emend.N.Li ex L.K.Fu:含四属:Cathaya Chun & Kuang, Larix Mill., Picea A.Dietr., Pseudotsuga Carr.;冷杉亚科Subfam.Abietideae Pilger, emend.Frankis:含五属:Abies Mill., Cedrus Trew, Keteleeria Carr., Pseudolarix Gordon, Tsuga Carr.。运用分支分析探讨各属的演化关系,并综合表征和分支分析结果,结合古植物学资料,构思和绘出了以地质年代为纵作标的松科系统发育树。     

Isolation and Characterization of Total DNA from Several Endangered Species and Their Allies

A low pH extraction medium with high salts, which avoids ionization and subsequent oxidation of phenolic compounds during tissue grinding and precipitation of large amounts of materials, were successfully used to obtain total DNA from Cathaya argyrophylla Chun et Kuang, Paeonia suffruticosa var. spontanea, Cimici fuga nanchuanensis Hsiao, Adenophora potaninii (Congeneric species with A. lobophylla) etc. The DNA yields, quality and purity were characterized. These isolated DNA could be used directly for RFLP and RAPD analysis which are useful as molecular genetic markers without sedimentation in cesium chloride gradient or column chromatography. A fast, inexpensive and reliable procedure has been developed for detecting the genetic diversity of endangered plants.     

几种濒危植物及其近缘类群总DNA的提取与鉴定

用低ｐＨ 介质,高盐沉淀蛋白质方法成功地从银杉（Ｃａｔｈａｙａ ａｒｇｙｒｏｐｈｙｌｌａ Ｃｈｕｎ ｅｔＫｕａｎｇ）、矮牡丹（Ｐａｅｏｎｉａ ｓｕｆｆｒｕｔｉｃｏｓａ ｖａｒ． ｓｐｏｎｔａｎｅａ）、南川升麻（Ｃｉｍ ｉｃｉｆｕｇａ ｎａｎｃｈｕａｎｅｎｓｉｓＨｓｉａｏ）、裂叶沙参（Ａｄｅｎｏｐｈｏｒａ ｌｏｂｏｐｈｙｌｌａ）的同属种泡沙参（Ａ． ｐｏｔａｎｉｎｉｉ）等植物中提取和部分纯化了细胞总ＤＮＡ,并对其产率、质量和纯度作了鉴定。此方法的关键是用了一个低ｐＨ提取介质,它能有效防止组织破碎及沉淀大量材料时的电离化作用及酚化合物的进一步氧化。所得ＤＮＡ 不需经氯化铯梯度离心或柱层析,直接可用于限制性片断长度多态性（ＲＦＬＰ）及随机扩增的ＤＮＡ多态性（ＲＡＰＤ）等分子水平的遗传标记。为检测濒危植物的遗传多样性提供了一套迅速、简便和可靠的技术方案     

贵州大沙河银杉自然保护区植物资源考察

在对大沙河银杉自然保护区进行实地考察的基础上,通过对８８科１５２属约３００种常见维管植物的调查分析,初步认为该区内植物资源有如下特点：１）植物区系成分复杂,种子植物属的分布区类型有１２个,北温带分布、东亚分布、热带亚洲分布和泛热带分布类型比较多见;２）古老、残遗及稀有、濒危植物比较集中,其中国家重点保护植物８种;３）园林、观赏植物类型多样,杜鹃花属植物尤具特色;４）药用植物资源丰富,红豆杉〔Ｔａｘｕｓｃｈｉｎｅｎｓｉｓ（Ｐｉｌｇｅｒ）Ｒｅｈｄ．〕、雷公藤（ＴｒｉｐｔｅｒｙｇｉｕｍｗｉｌｆｏｒｄｉＨｏｏｋ．ｆ．）等多为珍贵药用植物。对保护区的现状也进行了分析和评价。     

八面山银杉林的遗传多样性和群体分化

采用水平淀粉凝胶电泳技术对分布于湖南八面山的濒危植物银杉(cathaya argyrophylla Chun etKuang)的遗传多样性和群体分化进行了初步研究。对13个酶系统25个等位酶位点的检测表明,该地区的银杉林群体遗传变异水平很低,多态位点比率 P=0.28,等位基因平均数 A=1.36,平均期望杂合度He=0.100;但3个小群体间存在着明显的遗传分化,基因分化系数高达G_ST=0.26,明显不同于其它裸子植物的报道。八面山银杉林低水平的遗传变异和明显的群体分化,一方面反映了银杉的古老性和残遗性,另一方面也说明在银杉的进化过程中可能发生了严重的遗传漂变,而且群体之间的基因流明显受阻。     

ANATOMICAL STUDIES OF CATHAYA (PINACEAE)

Cathaya Chun et Kuang is a monotypic genus and one of the gymnosperms endemic to China. We investigated Cathaya argyrophylla with both light and scanning electron microscopy to study the external and internal surfaces of leaf cuticle, leaf blade, petiole, shoot apex, young stem, bark, wood, young and old roots, and mycorrhizae. It is shown that Cathaya has unique characteristics as well as common features of the Pinaceae, there being a difference between Cathaya and Pinus and the rest of the family. So far as the vegetative organs are concerned, the genus is most closely related to Pseudotsuga and Larix. Data derived from the study of structures of vegetative organs of Cathaya are very different from those of reproductive organs, indicating the complexity of the problem of systematics and evolution in these plants. However, the present study supports the view that Cathaya should not be included in the genus Pseudotsuga as a new species.     

气候变化对孑遗植物银杉的潜在分布及生境破碎度的影响

以孑遗植物银杉(Cathaya argyrophylla Chun et Kuang)为研究对象,选取65个地理分布记录和19个生物气候因子(bio1—bio19),利用MaxEnt模型预测四种不同浓度路径下(RCP 2.6、RCP 4.5、RCP 6.0和RCP 8.5),银杉在2050s和2070s两个年代的潜在分布变化,并利用景观指数对气候变化情景下银杉适宜生境空间格局特征转变及生境破碎度变化进行分析。结果表明:在当前气候情景下,银杉适宜生境面积约占研究区面积的14.32%,主要分布于北纬24°—32°、东经105°—114°之间,位于四川盆地东南地区、云贵高原东北地区、南岭西段地区以及浙闽丘陵的北部地区。在未来不同气候情景下,银杉适宜生境变化特征显著,面积呈增加趋势,形状上整体呈四周向中间聚集。气候变化对银杉适宜生境的景观指数影响主要表现在斑块数量增多、斑块密度增加、面积加权平均形状指数变大,对分离度与聚散性影响较小;气候变化对银杉生境破碎化程度的影响表现在破碎化两极现象减弱,总体破碎化程度加剧。研究选取7个景观指数并结合PCA法得到综合的破碎度指数来定量分析银杉适宜生境破碎化程度变化,相比单一指标的定量评价和多个指标的定性分析,更能代表银杉生境的实际破碎化程度。     

银杉种群的空间分布格局

银杉（ＣａｔｈａｙａａｒｇｙｒｏｐｈｙｌｌａＣｈｕｎｅｔＫｕａｎｇ）种群的空间分布格局受银杉种群本身的生物学特性、种群的年龄和更新方式等及群落内小环境的共同影响。在老龄种群内,多表现为集群分布;在较年轻的种群内,多为随机分布。气候和立地条件基本一致时,群落内岩石的覆盖与土壤蚀形成的小环境。     

华南绞股蓝属植物及其混淆种类的研究鉴定

<正> 绞股蓝属(Gynostemma B1.)为葫芦科的草质藤本植物,在华南地区已知有4种,即单叶绞股蓝(G. simplicifolium B1.)、光叶绞股蓝(G. laxum(Wall.)Cogn.)、绞股蓝(G. pentaphyllum(Thunb.)Makino)和长梗绞股蓝(G. loilgipes C. Y. Wu)。而与其经常相混淆的有8种,其中属于葫芦科的有5种,即锣锅底(Hemsleya amabilis Diels)、蛇莲(H. sphaerocárpa Kuang et A. M. Lu)、雪胆(H. chinensis Cogn. )、纤花金盆(H. graciliflora(Harms) Cogn.)和地糍粑(H. dipteriga Kuang et A. M. Lu);属于     

湖北4种木本植物新记录及资源现状

2017～2019年,我们在对湖北五峰后河国家级自然保护区进行本底资源调查过程中发现了若干新记录。本文对其中4种木本植物新记录进行报道,分别为乐东拟单性木兰[Parakmeria lotungensis(ChunC.H. Tsoong) Y.W. Law]、乐昌含笑(Michelia chapensis Dandy)、峨眉鹅耳枥(Carpinus omeiensis H.H. HuD. Fang)和尾叶紫薇(Lagerstroemia caudata ChunF.C. How ex S.K. LeeL.F. Lau)。同时,我们也对这4种木本植物的种群现状、濒危状况和资源利用进行了调查,为进一步保护工作的开展提供了基础。