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1.
Microtropis macrocarpa C.Y. Cheng & T.C. Kao has been treated as a synonym of Microtropis macrophylla Merr. & Freeman in most taxonomic reports in China. According to our study, M. macrocarpa is an independent species endemic to Yunnan, China. Microtropis macrophylla and Microtropis pachyphylla Merr. & Freeman should be treated as synonyms of Microtropis longifolia Wall. ex Kurz. M. macrocarpa is also identified as a critically endangered species, CR B 1 ab (i,ii,iii,v), based on the IUCN Red List Categories and Criteria. The foliar surface, anther and pollen structures were also observed with a scanning electron microscope.  相似文献   

2.
Miliusa bannaensis X. L. Hou, a new species of the Annonaceae from Xishuangbanna, Yunnan Province, China, is described and illustrated. It is related to M. macrocarpa Hook. f. & Thoms. by its larger flowers 2 cm long and 2.5 cm in diam., but differs in it  相似文献   

3.
河南山黧豆属和杭子梢属订正   总被引:1,自引:0,他引:1  
归并了山黧豆属1种和杭子梢属1变种。即将河南香豌豆Lathyrus henanensis S.Y.Wang作为安徽山黧豆L.anhuiensis Y.J.Zhu et R.X.Meng的新异名;白花杭子梢Campylotropis macrocarpa(Bge.) Rehd.var.alba S.Y.Wang作为杭子梢原变种C.macrocarpa (Bge.)Reehd.var.macrocarpa的新异名。  相似文献   

4.
HPLC法测定藜豆中左旋多巴的含量   总被引:2,自引:0,他引:2  
黄海滨  苏健  谭叶憧 《广西植物》2004,24(5):460-462
采用HPLC法建立测定藜豆中左旋多巴含量的方法。色谱柱为岛津C-18甲基硅烷柱(250 min×4.6mm,5μm),流动相为甲醇:0.1 mol/L醋酸溶液(25:75,v/v),以硫唑嘌呤为内标物,检测波长280 nm,流速1.0 mL/min,柱温为室温,供试品的前处理方法为微波辅助提取法。结果表明,该方法准确度高,线性关系好,重现性好,平均加样回收率为97.34%,RSD 1.01%(n=5),结果满意。  相似文献   

5.
The glutamine synthetase of Suaeda maritima. In vivo and in vitro action of NaCl Glutamine synthetase (GS; EC 6.3.1.2) was isolated and characterized from roots and aerial parts of the halophyte Suaeda maritima (L.) Dum. var. macrocarpa Moq. Km values of GS were identical in both types of organ and unchanged by the salinity in the medium. Addition of NaCl in the culturing solution increased the specific activity of the enzyme especially in the aerial parts, where GS is more abundant. This increase was all the more pronounced if the plant-salt contact period was extended (between 21 and 45 days). In vitro the addition of 0 to 500 m M of salt did not affect the activity of GS at satured substrate concentrations. At low glutamate concentrations in combination with 300 m M NaCl or more, a slight competitive inhibition was observed, never over 18%. – The remarkable insensibility of GS to salinity in vitro and the stimulating effect of NaCl in vivo on the synthesis of the leaf enzyme indicates that GS plays a fundamental part in the assimilation of NH4+ in the halophyte Suaeda maritima var. macrocarpa.  相似文献   

6.
7.
科尔沁沙地黄榆种子散布的空间差异及规律   总被引:1,自引:0,他引:1       下载免费PDF全文
黄榆(Ulmus macrocarpa)是典型的风播植物, 在科尔沁沙地可以形成单一优势种林地。通过对其林下随机取样和林缘与孤立树不同方向从树基部向外的有序取样调查, 分析了黄榆林下和林缘外不同距离的种子沉降特征、林缘和孤立树种子散布方向的差异性与规律性。结果表明, 黄榆平均种子密度以林下最大, 林缘3 m处已显著减小, 林缘外随着距离增加黄榆平均种子密度呈指数减少态势, 且越远越不均匀。林缘和孤立树不同方向在26 m内, 单位面积连续分布的种子累积数量均以顺风向频率大的东北方向最多, 以逆风向频率大的西南或西方向最少。林缘和孤立树共10个方向的垂直断面从树基部向外的单位面积种子数量频度均符合Weibull分布和对数-正态分布密度函数(χ2(α) < 0.900), 具有相同的种子散布格局。在科尔沁沙地自然条件下, 黄榆在各方向具有相同的“远距离”种子散布机制。  相似文献   

8.
基于树轮年代学方法,利用玉龙雪山、哈巴雪山和普达措国家公园海拔上限大果红杉树轮宽度资料,分别建立3个样点大果红杉的差值年表(RES),研究其径向生长对气候响应的异同,探讨影响滇西北大果红杉生长的关键气候因子.结果表明: 生长季初期(5月和6月)温度是影响滇西北大果红杉生长的主要因子,与3个样点的径向生长表现出显著正相关关系,同时普达措国家公园大果红杉还受生长季以前温度的影响,分别与上年7月和11月温度呈显著负相关和显著正相关;3个样点大果红杉生长对降水的响应存在差异,随着纬度升高主要由负相关转为正相关,大果红杉径向生长与降水的关系在玉龙雪山(纬度梯度最南)主要表现为与生长季初期降水量呈显著负相关,在哈巴雪山(纬度梯度中部)表现为与9月降水量呈显著负相关,在普达措国家公园(纬度梯度最北)表现为与3月降水量呈显著正相关.另外,7月降水的增多有利于玉龙雪山大果红杉的生长.基于气候模型预测,综合大果红杉对温度和降水响应模式与响应程度分析,未来气候变化有利于滇西北高原大果红杉的径向生长.  相似文献   

9.
The composition of the leaf essential oils of all the species of Juniperus in sect. Juniperus (=sect. Oxycedrus) are reported and compared (J. brevifolia, J. cedrus, J. communis, J. c. var. saxatilis, J. c. var. oblonga, J. formosana, J. oxycedrus, J. o. subsp. badia, J. o. subsp. macrocarpa, J. o. subsp. transtagana, J. rigida, J. r. subsp. conferta, J. sibirica, J. taxifolia and J. t. var. lutchuensis). In addition, DNA fingerprinting by RAPDs was utilized. Based on these data, several taxa remained at the same taxonomic level: J. brevifolia, J. cedrus, J. communis, J. c. var. saxatilis, J. formosana, J. oxycedrus, J. rigida, J. r. var. conferta, and J. taxifolia. However, several taxa exhibited considerable differentiation that warranted their recognition at the specific level: J. oblonga M.-Bieb. (=J. communis var. oblonga), J. badia H. Gay (=J. oxycedrus subsp. badia), J. macrocarpa Sibth. and Sm. (=J. oxycedrus subsp. macrocarpa), J. navicularis Gand. (=J. oxycedrus subsp. transtagana), J. sibirica Brugsd. (=J. communis var. saxatilis in part), and J. lutchuensis Koidz. (= J. taxifolia var. lutchuensis).  相似文献   

10.
报道了我国丝瓜藓属Pohlia两新种,即产自云南的明齿丝瓜藓 P.hyaloperistoma Zhang,Li &; Higuchi和产自西藏的疏叶丝瓜藓P.macrocarpa Zhang,Li&;Higuchi。前者主要特征为蒴齿透明无疣,后者孢子体大型且雌雄异株。  相似文献   

11.
Eleutharrhena macrocarpa is a grade protected wild plant,also known as one of the tiny population. Through consulting relevant literature and records, access specimen investigation and field survey, A survey on geographical distribution、community and population status of it was conducted. The results show that: (1) there are a counter of 19 distribution points of Emacrocarpa, since 1910, the first time it was found in China; (2) E. macrocarpa is discontinuously distributed in the tropical rainforest regions of the south, southeast and southwest of Yunnan and Napo in Guangxi. Due to its habitat were severely damaged, 9 of the original record distribution points were disappeared, the number of existing distribution points which was reliable reduce to 10; (3) According to the reliable survey, the number of it just is about 40 strains, and we did not see its seedlings. it show that its natural regeneration is difficulty. Based on the results of the survey, discuss its endangered reasons, and provides the theoretical basis to protect them effectively.  相似文献   

12.
The history, taxonomy, distribution, habitat and cultivation requirements of Huernia macrocarpa ssp. macrocarpa (A. Rich) Sprenger from Ethiopa and Huernia kennedyana Lavranos, a South African endemic, are discussed; the two species are fully described and colour illustrations are provided.  相似文献   

13.
The chemotaxonomic investigation of Crataegus x macrocarpa, a hybrid of C. laevigata and C. rhipidophylla, presents the qualitative and quantitative composition of its flavonoid pattern in relationship to its parent species for the first time. Six flavonoids were identified as vitexin-2'-O-rhamnoside (1), vitexin (2), isovitexin (3), rutin (4), hyperoside (5), and isoquercitrin (6). Furthermore, two flavonoids were isolated from C. x macrocarpa and identified as a diastereoisomeric mixture of (R)- and (S)-eriodictyol-7-O-beta-D-glucuronide (7) and luteolin-7-O-beta-D-glucuronide (8) by means of 1D- and 2D-NMR, MS, and UV experiments. Compounds 7 and 8 were isolated for the first time from Crataegus species. While missing in C. laevigata, their occurrence in C. rhipidophylla additionally emphasizes its chemotaxonomic relationship to C. x macrocarpa.  相似文献   

14.
Abstract: Spore germination of Culcita macrocarpa C. Presl and Woodwardia radicans (L.) Sm. from nine populations at the northern limit of their distribution, in the northwest Iberian Peninsula, was investigated. In a first experiment, population type and temperature (10, 15, 20, and 25 °C) were both found to affect germination percentage and germination time significantly in both species. There were also significant interactions between the two factors with respect to the percentage germination of C. macrocarpa and the germination time of W. radicans. In C. macrocarpa there was an outstanding increase in germination time at 15 °C and, above all, at 10 °C, whereas in W. radicans the most remarkable result was the existence of two populations with especially low germination percentages. In a second experiment, germination of 20 individuals from each population of W. radicans was compared with similar inter-population differentiation. Although its variability possibly has a genetic basis, these species are able to germinate successfully, and it seems probable that the season in which it occurs depends more on spore release than on thermal conditions in the populations. The effect of temperature on germination in both species does not explain their coastal distribution. Temperature is probably more important in limiting other stages of the life cycle.  相似文献   

15.
The development and morphology of the gametophytes of seven species of ferns from genus Pleopeltis are described and compared. The spore germination is Vittaria-type in P. astrolepis, P. crassinervata, P. macrocarpa, P. polylepis and P. revoluta. For P. angusta and P. mexicana it was proposed a new germination pattern is Pleopeltis-type. The prothallial development is Drynaria-type in P. astrolepis, P. crassinervata, P. macrocarpa, P. polylepis and P. revoluta and Ceratopteris-type for P. angusta and P. mexicana. The gametangia are typical of the leptosporangiate ferns, sporophytes after six and a half months in culture did not appeared.  相似文献   

16.
张树仁 《植物研究》1998,18(3):372-376
研究了产于西伯利亚的西伯利亚嵩草Kobresia sibirica (Turcz.ex Ledeb.) Boeck.,产于北美的K.hyperborea Porsild和K.macrocarpa Clokey。三者之间无显著差异,并且它们的雌花都具有由一至三枚小鳞片组成的花被。因此,它们为同种植物, K.hyperborea包括其变种var.alaskana Duman和var.lepagei Duman及K.macrocarpa被降为西伯利亚嵩草的异名。西伯利亚嵩草分布于亚洲和北美洲的北极和亚北极地区,可能起源于亚洲,由东西伯利亚通过白令海峡散布到北美。  相似文献   

17.
油瓜油的甘油三酯组成研究   总被引:1,自引:0,他引:1  
廖学焜  郭慧然   《广西植物》1988,(3):288-290
油瓜的种仁油可供食用。应用高效液相色谱技术,从油中分离分析出12种甘油三酯,其主要甘油二醋是甘油二亚油酸—棕榈酸酯(PLL)、甘油二棕榈酸—亚油酸酯(PLP)、甘油—棕榈酸—亚油酸—油酸酯(PLO)和甘油二棕榈酸—油酸酯(POP)。  相似文献   

18.
An array of 10 wild Brassica species with chromosome number 2n = 18 represented by 34 populations was analyzed for genome similarity using genomic and cDNA clones. Species studied included B. bourgeaui (Webb) O. Kuntze, B. cretica Lam., B. hilarionis G.E. Post, B. incana Ten., B. insularis Moris, B. macrocarpa (Guss.) Caruel, B. montana Pourret, B. oleracea L., B. rupestris Rafin., and B. villosa Biv. The RFLP data were used to calculate similarities between populations that were subsequently treated in a cluster analysis. Most populations of a species were grouped together and were separate from populations of other species. The previously identified B. incana - B. rupestris - B. villosa complex was verified, and genetic similarity between the species B. montana and B. oleracea was evident. An interesting association between B. insularis and B. macrocarpa was observed. The UPGMA analysis showed that the species tended to cluster according to geographic region: B. cretica and B. hilarionis comprise a cluster that could be called Eastern Mediterranean; B. oleracea, B. bourgeaui, and B. montana define an Atlantic - Western Mediterranean cluster; B. incana, B. rupestris, and B. villosa form an Italian group; and a B. insularis - B. macrocarpa association may be called Central Mediterranean.  相似文献   

19.
This study analyzed the effects of tree size, and correlated architectural tree characteristics, on the assemblages of ants and insect herbivores associated with Anadenanthera macrocarpa (Mimosaceae). The latter is a myrmecophilous tree species from the Atlantic rainforest in south-eastern Brazil. Ants and insect herbivores were collected in 30 individuals of A. macrocarpa , ranging from young individuals (>3 m in height) to emergent trees (up to 40 m). Tree height was a strong indicator of other tree characteristics, including trunk diameter, crown height, crown volume, and number of bifurcations. Ants were collected using arboreal pitfall traps and beating, while insect herbivores with beating only. There was a significant increase in both abundance and species richness of ants and insect herbivores with an increase in tree height. In addition, tree height had a significant effect on the species composition of ants and insect herbivores. Assemblages of both taxa showed a nested organization pattern. The species found in small- and medium-sized trees, in general, consisted of a subset of the species found in the crowns and branches of larger, canopy or emergent trees. Thus, in A. macrocarpa , there was not a replacement of insect species with plant ontogeny. This finding is at variance with those conducted in tropical evergreen forests and which show a clear stratification between the understory and canopy insect faunas. Additional studies are needed to explain these contrasting patterns, but it is possible that differences in microclimate are involved. As the forest we studied is semi-deciduous, microclimatic gradients between the understory and the canopy habitat are probably less severe than in an evergreen forest, thus resulting in a lower turnover of species.  相似文献   

20.
BACKGROUND AND AIMS Habitats in mountains are often isolated. Plants growing in these sites face severe dispersal limitations, but also difficulties for recruitment. The focus was laid on the magnitude of genetic differences among populations but also on the size of potentially occurring clones. METHODS: RAPD fingerprints were obtained from 23 populations in southern Mongolia. Sampling covered the entire distribution range of Galitzkya macrocarpa; samples of G. potaninii represented only the Mongolian part of its mainly northern Chinese range. KEY RESULTS: The Mongolian endemic G. macrocarpa showed moderately strong population differentiation (Phi ST = 0.251), and limited evidence for isolation by distance. Local genetic diversity was not positively correlated to habitat size, and not reduced in peripheral populations. Clonal growth is possible, but most plants originate from sexual reproduction. In contrast, populations of G. potaninii were highly differentiated (Phi ST = 0.550); and the most remote outposts had reduced genetic diversity. In these areas, isolation is expected to date back to glacial times. CONCLUSIONS: Effects of natural fragmentation differ among species. Both are rare, but G. macrocarpa appears to be able to maintain genetic diversity over its range. Clonal growth is an option in its mixed reproduction strategy and allows survival under harsh conditions. In contrast, genetic structure in G. potaninii gives reason for concern, and further studies on population dynamics are needed.  相似文献   

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