杏叶沙参胚囊的酶法分离：受精、合子生长与胚乳发育

胚囊酶法分离作为植物胚胎学中的一项观察技术已为不少作者所采用。本实验室用此技术观察了多种植物的成熟胚囊,泡相与芝麻的大孢子发生和雌配子体发育过程,以及金鱼草与向日葵受精后的若干变化。本文以杏叶沙参为材料,进一步探索其在观察受精、胚和胚乳发生过程中的应用前景。材料和方法实验材料为杏叶沙参(Adenophora axilliflora)。自然传粉后定期取样固定胚珠。固     

濒危植物裂叶沙参的大小孢子发生及雌雄配子体发育

本文以近缘广布种泡沙参为对照,对濒危物种裂叶沙参进行了大小孢子发生和雌雄配子体发育的研究。裂叶沙参的药壁发育为双子叶型,绒毡层为腺质型,细胞含两核。小孢子母细胞在减数分裂过程中胞质分裂为同时型。小孢子四分体为四面体型,成熟花粉粒为2-细胞型。胚珠倒生,单珠被,薄珠心,大孢子四分体为线形排列,胚囊发育为蓼型。成熟胚囊中两极核在受精之前融合为一个大的次生核。当胚囊发育至单核胚囊时,珠被的最内层细胞发育为珠被绒毡层。濒危植物裂叶沙参在大、小孢子发生及雌、雄配子体的发育过程中,未见有败育及其它异常现象;与对照种泡沙参相比,也未见有差异,这说明裂叶沙参的致濒原因不在于有性生殖过程。     

泰山沙参属植物资源调查与营养成分分析

目的:了解泰山沙参属植物资源现状,测定其根中脂肪、蛋白质及多糖的含量,为合理开发利用泰山沙参属植物资源提供依据。方法:采用野外实地调查法进行资源考察;分别用索氏提取法、考马斯亮蓝法和苯酚-硫酸法测定脂肪、蛋白质和多糖的含量。结果:采集的100余份标本,经鉴定为沙参属植物狭叶沙参[Adenophora gmeli-nii(Spreng)Fisch.]、石沙参(Adenophora polyantha Nakai)、杏叶沙参(Adenophora stricta Mig.)及细叶沙参(Adeno-phora paniculata Nannf.)。泰山沙参属植物狭叶沙参、石沙参、杏叶沙参和细叶沙参脂肪含量分别为2.14%～7.34%,4.27%～7.72%1,.54%～2.51%和4.98%。蛋白质含量分别为0.60～2.10 mg/g0,.80～1.89 mg/g,0.83～0.89 mg/g和1.05 mg/g,多糖含量分别为20.58%～63.21%2,7.74%～65.14%,43.14%～48.47%和45.60%。结论:泰山野生沙参属植物资源丰富,品种多、分布广、蕴藏量大,多糖含量较高,具有较大的开发前景。     

濒危物种裂叶沙参及其近缘广布种泡沙参的遗传多样性研究

根据对１２个形态性状的统计分析和１０个基因位点的等位酶检测,探讨了濒危植物裂叶沙参及其近缘广布种泡沙参的遗传多样性水平,对３个裂叶沙参和６个泡沙参天然群体的遗传分析表明,两种沙参属植物均具有很高的遗传变异水平,这种变异性既体现在形态学水平上,也体现在酶位点水平上,在２个茎叶形状以及１０个花果和种子形状上,濒危种裂叶沙参的变异性均与广布种相当,同样,根据７个酶系统１０个等位酶位点的度量,裂叶沙参群体     

裂叶沙参与泡沙参剖解生态学的比较研究

借助于光镜和扫描电镜,系统观察了濒危植物裂叶沙参（Ａｄｅｎｏｐｈｏｒａ ｌｏｂｏ－ｐｈｙｌｌａ Ｈｏｎｇ）的根、芦头、茎和叶的解剖特性及茎、叶、种子的表面形态特征,并将有关性状与广布沙参（Ａ．ｐｏｔａｎｉｎｉｉ Ｋｏｒｓｈ．）作了对比研究。结果表明,两种沙参在叶表皮细胞形态,垂周壁式样,角质层初级雕纹及次级雕纹;叶片气孔形状及外拱盖外缘纹饰及内缘形状,保卫细胞上角质层薄厚及蜡质纹饰;叶表毛状体形状     

裂叶沙参和泡沙参气孔行为与蒸腾特性的关系

采用LI-6400便携式光合分析系统对裂叶沙参和泡沙参进行了不同遮光水平蒸腾速率的测定,并同步测定了叶片气孔大小、气孔密度、气孔开度和气孔导度等气孔行为.采用相关系数和通径系数分析方法分析了不同遮光水平裂叶沙参和泡沙参气孔行为与蒸腾特性的关系.结果表明:不同遮光水平测定的气孔行为对裂叶沙参和泡沙参蒸腾作用的直接影响大致相同,其中,两种沙参的气孔密度对蒸腾速率的直接影响较大.但泡沙参的气孔导度与蒸腾作用具有极显著的相关关系.     

裂叶沙参与泡沙参解剖生态学的比较研究

借助于光镜和扫描电镜,系统观察了濒危植物裂叶沙参(Adenophora lobo-phylla Hong.)的根、芦头、茎和叶的解剖特征及茎、叶、种子的表面形态特征,并将有关性状与广布种泡沙参(A.potaninii Korsh.)作了对比研究。结果表明,两种沙参在叶表皮细胞形状,垂周壁式样,角质层初级雕纹及次级雕纹;叶片气孔形状及外拱盖外缘纹饰及内缘形状,保卫细胞上角质层薄厚及蜡质纹饰;叶表毛状体形状及纹饰,茎中皮层占茎横切面的比例;茎中有无髓纤维等方面存在着明显差异。相对于泡沙参,裂叶沙参单株叶面积大,生物量高,表皮角质层薄,单位面积内被毛数量少,栅栏组织薄,气孔周围蜡质沉积颗粒少;茎的直径大,皮层较薄等。这些特征表明裂叶沙参对旱生生境适应能力弱,而泡沙参对旱生生境适应能力强。     

狭叶沙参复合体(桔梗科)的物种生物学研究

通过对狭叶沙参复合体进行居群(共46个)采样、引种、栽培实验,生物学特性观察,染色体观察 (已发表),杂交、同工酶比较、形态性状的定性定量分析、茎解剖和花粉形态的观察,发现：(1)该 复合体主要进行异花授粉,实生苗第二年才抽茎生花;(2)32个居群的染色体计数表明,在辽宁东部、 辽宁西部(绝大部分地区)和山西霍县的居群都为二倍体(2n=34),而其它地方的居群为四倍体(2n 68);(3)叶的酯酶同工酶的变异大,和一些形态特征,尤其是叶的形态和大小的变异相似,而种子的酯 酶同工酶则相当稳定;(4)通过9个居群的杂交试验,在狭叶沙参和石沙参四倍体居群间得到了一 些F1种子,而辽宁西部二倍体与上述的四倍体居群间的杂交未产生任何F1种子;(5)性状分析(包括 聚类分析与主成份分析)和茎解剖的研究,揭示了它们在叶、果实、花和种子的形态、髓纤维组织的有无、 叶锯齿和花萼裂片齿的有无和多少等形状上的变异幅度,并据此分辨出8个宗。其中辽宁西部的二倍 体宗形态上相当独特,被提升为种的等级。 其余7个宗,根据不同的分化程度被处理为三个种和5个 亚种;(6)运用杂交指数法分析了石沙参和狭叶沙参在太行山一带杂交的可能性;(7)分析讨论了复合体内各类群的起源和进化关系。     

不同海拔高度泡沙参叶片形态研究

对不同海拔高度的泡沙参叶表形态、气孔特征进行了观察,比较了不同海拔高度对泡沙参叶片生态适应的影响。结果表明：泡沙参叶表皮角质层较厚,被有大量表皮毛和蜡质颗粒,海拔越高越明显;泡沙参气孔复体类型均为不规则型,气孔保卫细胞角质层较厚,气孔口较小,气孔密度与气孔大小成反比,并且气孔大小随海拔升高而减小,气孔密度随海拔升高而增大,是一种抗旱适应的表现。     

用核糖体DNA的ITS序列探讨裂叶沙参的系统位置——兼论ITS片段在沙参属系统学研究中的价值

本文采用PCR直接测序方法,对来自沙参属全部2组7亚组的10个种和作为外类群的风铃草属2个种的核糖体DNA　ITS片段进行了序列分析。在重点探讨裂叶沙参分类地位的同时,分析了ITS片段序列在沙参属系统发育重建中的价值。结果表明,在沙参属中,ITS片段在长度、GC含量和位点变异量上均比较一致;长度539bp～541 bp,GC含量57％～60％,信息位点只占总位点的3．9～6％。采用PAUP软件进行的系统发育分析表明,裂叶沙参A．lobophylla与大花盘亚组的A．himalayana组成一支,而不是象以往形态学和杂交试验所推断的与泡沙参A．potaninii或A．stenanthina近缘。可见,ITS序列进一步支持将裂叶沙参移出泡沙参复合体甚至移出有齿亚组的推论,但同时也表明将其作为A．stenanthina的近缘种是不适宜的。尽管本研究所测定的类群已涵盖了整个沙参属,但种间序列的两两比较表明,沙参属种间在ITS片段上的分化很小(0.0～3.9％),相比之下,沙参属类群与风铃草属类群间的分化却很高(17.8％～19.2％)。这大概和沙参属起源较晚、遗传分化较小有关。本文还就ITS片段在沙参属和桔梗科系统学研究中的价值进行了讨论。     

云南沙参属一新种

云南沙参属一新种钱义咏（云南省思茅行署林业局,思茅市６６５０００）ＡｎｅｗｓｐｅｃｉｅｓｏｆＡｄｅｎｏｐｈｏｒａｆｒｏｍＹｕｎｎａｎＱｉａｎＹｉｙｏｎｇ（ＦｏｒｅｓｔｒｙＢｕｔｅａｕ,ＳｉｍａｏＡｄｍｉｎｉｓｔｒａｔｉｖｅＯｆｆｉｃｅ,Ｓｉｍａｏ６６...     

内蒙古沙参属一新异名和一新名称

索伦沙参Adenophora suolunensis P. F. Tu &; X. F. Zhao与小花沙参A. micrantha D. Y. Hong为同一种植物, 故将前者处理为后者的异名; 坛盘沙参A. urceolata Y. Z. Zhao是壶花沙参A. urceolata C. Y. Wu的晚出同名, 另提出新名库伦沙参A. kulunensis Y. Z. Zhao。     

裂叶沙参和泡沙参种群有性生殖和无性繁殖的比较

通过对裂叶沙参(Adenophora lobophylla Hong)和泡沙参(A.potaninii Korsh.)种群有性生殖和无性繁殖特性的对比,揭示濒危植物裂叶沙参的种群内部致濒机制。结果表明:裂叶沙参种群幼苗抢占草本层上层空间能力弱于泡沙参种群;裂叶沙参种群是以相对长的生殖期和高产籽量来适应环境;裂叶沙参种群开花结实量虽高于泡沙参种群,但其中成熟种子少,种子质量差,致使其种群由种子到一年生幼苗的转化率极低,并且幼苗生活力弱,是导致其种群濒危的重要内部原因。裂叶沙参种群除有性生殖外还兼有较弱的无性繁殖,是对其有性生殖的一个重要补充。     

Comparative Studies of Sexual Reproduction and Asexual Propagation Between Populations of Adenophora lobophylla and A. potaninii

To reveal the internal mechanism which lead to the endangerment of the AdenophoUa lobophylla Hong population, comparative studies of sexual reproduction and asexual propagation between the populations of A. lobophylla and A. potaninii Korsh were carried out. Young seedlings of A. lobophylla had less ability to occupy the uper space of the herbaceous layer than those of A. potaninii. The A. lobophylla population produced much more seeds and lived a long reproductive life to adapt the ambient environment. Though the number of flowers and fruits of A. lobophylla population was more than those of A.potaninii population, the number of its ripe seeds as well as the quality was less. Thus, the development rate from its seeds to one-year old seedlings was very low, and viability of its young seedlings was very poor. This could be the important factor causing the imminent population endangerment of A. lobophylla. Besides the sexual reproduction, the A. lobophylla population also had a comparatively tiny ability of asexual propagation, which was advantageously complementary to its sexual reproduction.     

A Reevaluation of the Status of A. lobophylla Based on ITS Sequence,with Reference to the Utility of ITS Sequence in Adenophora

Adenophora Fisch. (Campanulaceae)is a medium-sized and diverse genus, which occurs mainly in eastern Asia, particularly in China. Although several taxonomic systems have been proposed, there is still much debate on the delimitation and systematic arrangement of the species within the genus, due mainly to high variation in morphology, habitats, phenotypic plasticity, and potential hybridization. A. lobophylla Hong is a rare perennial endemic to several counties of Sichuan, China. Since this species was recognized, much work has been done on its taxonomic status, including morphology, crossing experiment and allozymes. However, evidence available is not concordance so far, and its relationship with other species within the genus remains largely uncertain. In the present paper, the internal transcribed spacer(ITS) region of 18s～26s nuclear ribosomal DNA was sequenced in 10 representatives of Adenophora and two outgroup species of Campanula to assess its utility for phylogenetic reconstruction in Adenophora, in addition to reevaluation of the taxonomic status of A. lobophylla. The results indicate that there exist high sequence alignability and length conservation among ITS sequences, with informative sites being 3.9% and length ranging from 539 to 541 bp and G + C content varying from 57% to 60%. Phylogenetic　analyses using Fitch parsimony show that A. lobophylla is closely related to A. himalayana instead of A. potaninii or A. stenanthina as revealed by previous morphological work and crossing experiment. The ITS phylogeny is generally congruent with other evidence in that A. lobophylla should be removed from the A. potaninii complex or even subsect. Microdiscus. Its appropriate placement, however, should be further explored. In pairwise comparisons at unambiguously aligned sites, sequence divergence was relatively low among Adenophora species with the values ranging from 0.0 to 3.9% in spite of the fact that the species surveyed covered all of the sections and subsections of the genus. In contrast, high sequence divergence is found among Adenophora and Campanula species with the values from 17.8 % to 19.2 %. The low divergence among Adenophora species is justified considering its recent origin, and also suggests that ITS sequence would provide a promising source of nuclear phylogenetic markers to reconstruct the phylogeny within Campanulaceae on the tribe and family levels.     

中国沙参属花粉形态的研究

对分布于我国的沙参属３２种（亚种,变种）植物的花粉形态进行了光学显微镜和扫描电镜的观察,研究结果表明：（１）沙参属植物花粉形态较相似,但其外壁纹饰,厚度,小刺密度,萌发孔情况在种,亚种,变种鉴别上有一定的意义。（２）本属花粉粒演化趋势为：表面条网状,条脊窄,小刺多,网孔类圆形→表面条状,脑纹状,条脊宽,小刺少,网孔不规则形。（３）花粉形态结合植物形态和染色体演化趋势,推断本属各组的演化关系为：基生     

国产沙参属五个种的核型研究

首次报道了５种国产沙参属（Ａｄｅｎｏｐｈｏｒａ）植物的染色体数目和核型。北方沙参Ａ．ｂｏｒｅａｌｉｓＨｏｎｇｅｔＹ．Ｚ．Ｚｈａｏ的核型公式为２ｎ＝３４＝２８ｍ＋４ｓｍ（２ｓａｔ）＋２ｓｔ（２ｓａｔ）;雾灵沙参Ａ．ｗｕｌｉｎｇｓｈａｎｉｃａＨｏｎｇ的核型公式为２ｎ＝３４＝２６ｍ（４ｓａｔ）＋６ｓｍ＋２ｓｔ或２ｎ＝３４＋１Ｂ＝２６ｍ（４ｓａｔ）＋６ｓｍ＋２ｓｔ＋１Ｂ;秦岭沙参Ａ．ｐｅｔｉｏｌａｔａＰａｘｅｔＨｏｆｍ．的核型公式为２ｎ＝３４＝２６ｍ（２ｓａｔ）＋６ｓｍ＋２ｓｔ或２ｎ＝３４＋１Ｂ＝２６ｍ（２ｓａｔ）＋６ｓｍ＋２ｓｔ＋１Ｂ;裂叶沙参Ａ．ｌｏｂｏｐｈｙｌａＨｏｎｇ的核型公式为２ｎ＝３４＝２６ｍ＋４ｓｍ（２ｓａｔ）＋４ｓｔ或２ｎ＝３４＋２Ｂ＝２６ｍ＋４ｓｍ（２ｓａｔ）＋４ｓｔ＋２Ｂ。泡沙参Ａ．ｐｏｔａｎｉｎｉＫｏｒｓｈ的核型公式为２ｎ＝３４＝２８ｍ（２ｓａｔ）＋４ｓｍ＋２ｓｔ。它们同以往报道的其它种的核型相似：以中部着丝点染色体（ｍ）为主,至少具一对近端着丝点染色体（ｓｔ）和一对随体染色体,核型的对称程度较高,着丝点端化值（Ｔ．Ｃ）为５８．４％～６２．０％。结合其它性状,讨论了裂叶沙参的特殊性     

泡沙参同工酶基因位点的遗传分析

利用聚丙烯酰胺凝胶电泳技术 ,对来自天然群体 (居群 )的泡沙参 (Adenophora potaninii Korsh.)及其人工杂交子代进行了 8种同工酶的电泳检测和谱带遗传分析 ,以确定编码这些酶系统的基因位点和等位基因。选用 4种不同的凝胶缓冲系统 ,对下列不同酶系统进行了酶谱的遗传分析 :天冬氨酸转氨酶 (AAT)、酯酶 (EST)、甲酸脱氢酶 (FDH)、谷氨酸脱氢酶 (GDH)、异柠檬酸脱氢酶 (IDH)、乳酸脱氢酶(LDH)、苹果酸酶 (ME)和超氧化物歧化酶 (SOD)。结果表明 ,这 8种酶系统至少由 1 8个基因位点编码 ,其中 1 2个位点为遗传稳定的等位酶位点 ,是可靠的遗传标记。酶谱的分离式样表明 ,EST为单聚体结构 ,AAT、FDH、IDH、SOD为二聚体结构 ,GDH为六聚体结构。最后对同工酶的器官和发育特异性以及同工酶基因位点的遗传分析进行了讨论     

Genetic Analysis of Isozyme Loci in Adenophora potaninii Korsh.

Enzyme polymorphism in Adenophora potaninii Korsh. was investigated using vertical slab polyacrylamide gel electrophoresis. Genetic analysis of the population samples and the progeny of intraspecific crosses allowed the verification of the isozyme loci from eight enzyme systems. The system studies included aspartate aminotransferase (AAT), esterase (EST). formate dehydrogenase (FDH), glutamate dehydrogenase (GDH), isocitrate dehydrogenase (IDH), lactate dehydrogenase (LDH), malic enzyme (ME) and superoxide dismutase (SOD). The results indicated that the eight enzyme systems are specified by at least 18 loci, 12 of which behaved as al|ozyme loci. Zymogram patterns showed that EST is monomeric and GDH is hexameric. AAT, FDH, IDH and SOD are apparently dimeric. The tissue and developmental variability are also discussed along with the genetic analysis of isozymes.