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1.
粗壮光叶拟单性木兰(Magnolia nitida var. robusta)被转移到拟单性木兰属,升级为种的等级。它与光叶拟单性木兰不同,特征是:长叶片,长叶柄,雌蕊短于雄蕊(相反,雌蕊长于雄蕊),花两性或雄性(花两性),被片乳白色(黄色),附属物尖(3.-3.5mm)。  相似文献   

2.
拟单性木兰属(木兰科)植物的分类学修订   总被引:2,自引:0,他引:2  
根据标本研究和野外调查,对木兰科(Magnoliaceae)的拟单性木兰属(Parakmeria Hu &; Cheng)进行了分类学修订。回顾了此属的分类学简史,阐述了保留拟单性木兰属的理由,将Magnolia Linn. subgenus Gynopodium Figlar &; Noot. section Gynopodium 作为拟单性木兰属的新异名,将Magnolia yunnanensis (Hu) Noot. 和M. nitida W. W. Smith var. robusta B. L. Chen &; Noot.作为云南拟单性木兰(Parakmeria yunnanensis Hu)的新异名,将Magnolia omeiensis (Cheng) Dandy、M. lotungensis Chun &; C. H. Tsoong、M. nitida W. W. Smith var. lotungensis (Chun &; C. H. Tsoong) B. L. Chen &; Noot. 和Parakmeria lotungensis (Chun &; C. H. Tsoong) Law作为峨眉拟单性木兰(Parakmeria omeiensis Cheng)的新异名,确认拟单性木兰属含4种植物,列出了分种检索表,描述了各种的地理分布和生长环境。  相似文献   

3.
两种木兰科植物叶片光合作用的光驯化   总被引:9,自引:3,他引:6  
孙谷畴  赵平  曾小平 《生态学报》2004,24(6):1111-1117
测定了生长在全日、54%和21%日光强下需光植物火力楠(Michelia meachurei)和耐荫植物华东拟单性木兰(Parakmerialotungensis)叶片气体交换参数,用以估测降低光强对光合作用的限制和对低光的光驯化.生长在全日光强下火力楠的光饱和光合速率较华东拟单性木兰高.当日光强降低到54%,火力楠叶片光合速率降低幅度较华东拟单性木兰大.当日光降低至21%,华东拟单性木兰的表观量子产率和光能转换率较火力楠高.在全日光强下,火力楠的Vcmax较华东拟单性木兰高.随着日光强降低,两种木兰植物的Vcmax降低,当日光强降低至54%和21%,火力楠的Vcmax降幅较华东拟单性木兰大,火力楠Vcmax对光强降低较华东拟单性木兰敏感.生长光强降低,两种木兰植物内部CO2传导度(gi)降低.在低光强下火力楠仍保持较华东拟单性木兰高的gi.生长光强降低到全日光强的54%,火力楠gi对光合速率限制(Li)与在全日光强的条件下没有区别(p>0.05),表现火力楠gi对54%日光强的驯化;在54%的光条件下,华东拟单性木兰的呼吸速率对光合速率的限制(Lr)与全日光照无差别(p>0.05),显示呼吸速率对低光的驯化.两种木兰植物气孔导度对光合速率的限制(Ls)随光强降低而增大.在遮荫条件下种间叶特性差别明显,这亦反映出两种植物物种光合驯化的差异.火力楠gi对低光驯化,而华东拟单性木兰叶片对较高光强驯化更甚于对低光强.  相似文献   

4.
峨眉拟单性木兰群落特征的初步研究   总被引:5,自引:0,他引:5  
对峨眉山峨眉拟单性木兰群落特征与种群结构的初步研究表明:1、蛾眉拟单性木兰及其群落分布局限,地形、土壤、气候条件较为特殊;2、该群落与中国云南和东部亚热带常绿阔叶林具有广泛的联系,并具各“顶极群落”的特征;3、峨眉拟单性木兰林的两个基木群丛为:(A)蛾眉拟单性木兰+四川人头茶+包石栎-箭竹-苔草群丛与 (B)黄心夜合+大叶新木姜子+峨眉拟单性木兰-箭竹-单芽狗脊群丛;4、人类和猴群的活动与干扰直接威胁着该种种群和群落的生存与稳定。  相似文献   

5.
国产木兰科6属植物柱头表面形态比较   总被引:1,自引:0,他引:1  
用扫描电镜对中国产木兰科单性木兰属、木兰属、木莲属、含笑属、拟单性木兰属和观光木属的42种植物柱头表面形态进行观察.结果表明,42种木兰科植物的柱头均为干柱头,包含单细胞乳突型和多细胞乳突型两类.单性木兰属和观光木属植物是单细胞乳突型;木莲属、含笑属和拟单性木兰属植物是多细胞乳突型;木兰属中木兰亚属植物两型均有,而玉兰亚属则均为多细胞乳突型.结合其他证据,本文支持单性木兰属、木莲属、含笑属、拟单性木兰属和观光木属的建立,并认为在系统学问题较复杂的木兰属中,玉兰亚属是一个相对独立的单系类群,将其独立成属也不无道理,而木兰亚属可能不是一个单系类群,还需要进一步的深入研究,积累更多的性状数据.  相似文献   

6.
云南拟单性木兰的组织培养   总被引:7,自引:3,他引:4  
1植物名称云南拟单性木兰(Parakmeria yunnanensis Hu). 2材料材料采用茎尖和带腋芽的茎段.  相似文献   

7.
云南拟单性木兰的化学成分   总被引:9,自引:0,他引:9  
从云南拟单性木兰(Parakmeria yunnanensis Hu)的干燥嫩枝中首次分离得到6个化合物,它们的结构经各种波谱数据分别鉴定为云南拟单性木兰素A(parakmerinA,1),eupomatenoid-7(2),eupomatenoid-5(3),槲皮素(quercetin,4),芦丁(rutin,5)及丁香苷(syrigin,6),其中化合物1为一新的eupomatene型木脂素,其结构为2,3-二氢-2a-(4-羟基-3-甲氧基苯基)3β-甲基-5[E]-烯丙基苯并呋喃,对化合物2级3进行了首次^13C NMR归属。  相似文献   

8.
单性木兰属(木兰科)植物的分类学订正   总被引:1,自引:0,他引:1  
根据对单性木兰属Kmeria(Pierre)Dandy植物标本的研究和野外调查,补充描述了该属的一些形态特征,纠正了前人对该属描述中的一些错误,阐述了保留单性木兰属的理由,列出了分种检索表,将焕镛木属Woon-youngiaLaw和单性木兰组MagnoliaLinn.sect.Kmeria(Pierre)Figlar&Noot.作为单性木兰属的新异名,将焕镛木Woonyoungiaseptentrionalis(Dandy)Law和广西木兰MagnoliakwangsiensisFiglar&Noot.作为单性木兰KmeriaseptentrionalisDandy的新异名。  相似文献   

9.
绿化新秀——乐东拟单性木兰   总被引:1,自引:0,他引:1  
在我国众多的木兰科植物中,有一树形伟岸丰满,叶片浓绿光洁,花朵洁白芳香,具有极高园林观赏价值的绿化新秀,值得大力推广,那就是乐东拟单性木兰。 乐东拟单性木兰,别名乐东木兰、隆南,为木兰科拟单性木兰属常绿大乔木,是我国特有树种,并已被《中国植物红皮书》收载。树高20—30米,胸径  相似文献   

10.
单性木兰花粉壁超微结构的研究   总被引:2,自引:0,他引:2  
本首次报道单性木兰花粉的形态特征和外壁超微结构。花粉外部形态与木兰科各属特征一致,表明单性木兰花粉的原始性。但花粉外壁超微结构显示其外壁表面具皱波状纹饰;覆盖层浪状,具稀疏的小穿孔;柱状层很薄,主柱典型,直立,短而细。外壁超微结构表明单性木兰属在木兰亚族中是一个较进化的属。扫描电镜和透射电镜资料揭示出单性木兰在植物分类系统中的特殊地位和重要学术价值。  相似文献   

11.
乐东拟单性木兰花粉形态观察   总被引:16,自引:3,他引:13  
徐凤霞 《广西植物》2002,22(2):157-159,T001
观察了乐东拟单性木兰 ( Parakmeria lotungensis)的雄花及两性花花粉的外壁雕纹及花粉壁的超微结构。二者花粉的大小、轮廓、表面雕纹及花粉壁的结构均很相似 ,但两性花花粉的产量很低。可以认为拟单性木兰属是木兰科中两性花向单性花演化的过渡类群  相似文献   

12.
Pratylenchoides hispaniensis n. sp. is described and illustrated from a bisexual population found in a natural habitat at Santa Elena, Jaen, central Spain. Its main distinctive characters are very long esophageal gland lobe (81-117 μm; N'' = 51-71) overlapping the intestine 3 to 5 times the body width; lateral field with six incisures; stylet knobs sloping posteriorly; labial disc encircled by the irregular sectors of the first annule; tail cylindrical, extremity annulated, and frequently with a slight dorsal indentation of the hyaline portion at the end of the lateral field. Pratylcnchoides hispaniensis n. sp. appears closely related to P. megalobatus and P. nevadensis. It differs from the former primarily by its longer body length (761-998 vs. 430-621 μm), longer stylet length (20.5-24.4 vs. 18-21 μm), six incisures in the lateral field vs. four for P. megalobatus, and posteriorly sloping stylet knobs vs. rounded or anteriorly flattened knobs in P. megalobatus. It differs from P. nevadensis mainly by the shape of the stylet knobs (sloping in P. hispaniensis vs. rounded in P. nevadensis), length of esophageal lobe (81-117 vs. 34-82 μm), and position of esophageal gland nuclei (all posterior to esophago-intestinal junction in P. hispaniensis vs. at least one nucleus anterior to junction in P. nevadensis).  相似文献   

13.
Three new Longidorus species, L. alaskaensis n. sp., L. paralaskaensis n. sp., and L. bernardi n. sp., are described from specimens collected near Fairbanks, Alaska. Longidorus alaskaensis differs from all species of Longidorus by the presence of a caecum-like structure situated at the reflex of the oviduct. Longidorus paralaskaensis most closely resembles L. alaskaensis n. sp., L. crassus Thorne, L. picenus Roca, Lamberti &Agostinelli, and L. silvae Roca, differing from the last three of these species by having a parallel vs. a tapered lip region, and from all four by having a more narrowly rounded tail tip. Longidorus paralaskaensis differs from L. alaskaensis by having a longer odontostyle (119-128 vs. 110-118 μm) and by lacking the caecum-like structure found at the reflex of the oviduct. Longidorus bernardi n. sp. most closely resembles L. mirus Khan, Chawla &Seshadri, from which it differs by having a longer tail with a more acutely rounded tip, a longer body length (3.5-4.6 vs. 3.0-3.6 μm), and a larger c'' value (1.6-1.8 vs. 1.3-1.6). Longidorus bernardi differs from L. sylphus Thorne, L. africanus Merny, L. auratus Jacobs &Heyns, and L. conicaudatus Khan by having a slightly expanded lip region vs. a lip region with parallel body walls and a more finely rounded tail tip.  相似文献   

14.
Prunus pananensis Z. L. Chen, W. J. Chen & X. F. Jin, a new species of Rosaceae from central Zhejiang, China is described and illustrated. Micromorphological characters of the indumentum on young shoots, leaves, petioles and peduncles, including scanning electron microscope [SEM] images, are provided. This new species is morphologically similar to P. schneiderianae Koehne in having its young shoots, petioles and pedicels all densely villose, but differs in having bracts persistent, styles glabrous, stipules 8–9 mm long, stamens 28–30 of per flower, and drupes glabrous. The new species is also similar to P. discoidea (Yü & C. L. Li) Yü & C. L. Li ex Z. Wei & Y. B. Chang in having 2 or 3 flowers in an umbellate inflorescence, and bracts persistent and marginally glandular, but it differs in having young shoots and petioles densely covered with yellowish-brown villose trichomes; leaves rounded or slightly cordate at base, the mid-ribs and lateral veins abaxially densely covered with yellowish-brown villose trichomes; and hypanthium ca. 3 mm long, shorter than sepals. The atpB-rbcL and trnL-F intergenic chloroplast spacers are selected for identification of the new and its similar species.  相似文献   

15.
Hemicycliophora hellenica n. sp. is described and illustrated from a bisexual population found in Filippias, Epirus, Greece, in the rhizosphere of giant reed (Arundo donax) and unidentified aquatic plants along the edge of irrigation canals. Hemicycliophora hellenica n. sp. is characterized by a long stylet (more than 120 µm), body length (L = 1,078-1,634 µm; R = 303-362), and lateral field marked by three lateral lines in females and four in males. The lip region is distinctive in that the female labial disc is oval and offset from the first lip region annule, and protrudes markedly; the male labial disc is very large, offset and rectangular, and protrudes distinctly. Hemicycliophora hellenica n. sp. resembles H. megalodiscus Loof by possession of a strongly protruding labial disc, but differs in having a longer female body, more body annules, longer stylet, and dorsally and ventrally indented head annules. The male labial plate is larger than in H. megalodiscus, and the male has four incisures in the lateral field vs. three in H. megalodiscus.  相似文献   

16.
Merlinius paniculoides n. sp. is described from a bisexual Italian population found in northern Italy. This species has a coarsely annulated cuticle with approximately 30 longitudinal striae in addition to the six lateral field incisures; consequently the cuticle appears tessellate. The female tail is subcylindrical with a bluntly, rounded, non-annulated terminus. Merlinius paniculoides shares the tessellate cuticular ornamentation and the offset labial region with M. lenorus (Brown, 1956) Siddiqi, 1970 and M. tartuensis (Krall, 1959) Siddiqi, 1970. It differs from M. lenorus by the higher c and lower c'' ratios (c = 16-19 vs. 12-15 and c'' = 2.2-2,8 vs. 3.7) and greater number of longitudinal striae (28-32 vs. 24). It differs from M. tartuensis by a fewer number of annuti from stylet knob base to lip constriction (8-9 vs. 21), shorter stylet (19-21 vs. 24 μm), presence of males, and higher c'' value (c'' = 2.2-2.8 vs. 1.9).  相似文献   

17.
Lindernia kinmenensis Y. S. Liang, C. H. Chen, & C. L. Tasi sp. nov. from Kinmen (Taiwan) is described. The new species belongs to section Torenioides and is most similar to L. crustacea. It differs from the latter by the following characters: calyx pubescent between the ridges (vs pubescent on ridges), with (2)3(4) bristles on the ridge near the apex of the calyx‐lobes (vs without such bristles), corolla shorter, 6–8 mm long (vs 7–11 mm long) and pale purple (vs purple or blue), posterior theca with obtuse (vs acute) apex. This species is usually found in sandy wetlands. A line drawing, colour photos and SEM micrographs of pollen and seed as aids for identification are provided.  相似文献   

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