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51.
讨论了Clematis eriopoda Maxim和sect.Atragenopsis Boiss.的地位,认为这二分类群均应成立;描述了2新种,1新变种;过去长期被归并的卷萼铁线莲C.tubulosa得到恢复;Clematis heracleifolia var.ichangensis被转移改作卷萼铁线莲的变种;首次给出光叶铁线莲Clematis glabrifolia的果实的形态描述。  相似文献   
52.
The taxonomy of Lepisorus (J. Sm.) Ching sect. Lepisorus in China was revised based on herbarium specimen examinations, field observations, and microscopic study of rhizome scales, soral paraphyses, leaf epidermis, and spores. As a result, nine species were recognized: Lepisorus macrosphaerus (Baker) Ching, Lepisorus asterolepis (Baker) Ching, Lepisorus marginatus Ching, Lepisorus kuchenensis (Y.C. Wu) Ching, Lepisorus megasorus (C. Chr.) Ching, Lepisorus kawakamii (Hayata) Tagawa, Lepisorus subsessilis Ching & Y.X. Lin, Lepisorus affinis Ching, and Lepisorus nudus (Hook.) Ching. Lepisorus kawakamii (Hayata) Tagawa was reinstated; Lepisorus gyirongensis Ching & S.K. Wu and Lepisorus longus Ching were reduced to synonyms ofL. nudus and L. affinis, respectively. The subdivision ofLepisorus macrosphaerus was not accepted. Rhizome scales and paraphyses are the most useful characters for species delimitation as well as for infrageneric classification. Characteristics of the leaf epidermis and spore ornamentation are usually stable and thus of great significance in understanding the relationships among groups within the genus.  相似文献   
53.
Summary  The new species Eugenia pallidopunctata, E. caducibracteata, E. tenuiflora and E. breviracemosa from the Brazilian Amazon, all belonging to Eugenia sect. Racemosae (Myrtaceae), are described, illustrated and compared with their putative close relatives. Data on the geographic distribution and habitat are given for the new taxa, as well as illustrations.  相似文献   
54.
Ecological differentiation is widely seen as an important factor enabling the stable coexistence of closely related plants of different ploidy levels. We studied ecological and genetic differentiation between co-occurring sexual diploid and apomictic triploid Taraxacum section Ruderalia by analysing spatial patterns both in the distribution of cytotypes and in the distribution of genetic variation within and between the cytotypes. A significant relationship between ploidy level and elevation was found. This mode of ecological differentiation however, was not sufficient to explain the significant spatial structure in the distribution of diploids and triploids within the population. Strong congruence was found between the spatial genetic patterns within the diploids and within the triploids. We argue that this congruence is an indication of gene flow between neighbouring plants of different ploidy levels.  相似文献   
55.
Abstract: The embryology and seed structure of Paepalanthus sect. Actinocephalus species were studied. The embryological and structural seed characters fit well with those of the other commelinaceous families. Within the Commelinales sensu Dahlgren, Eriocaulaceae and Xyridaceae represent two embryologically close families. In Paepalanthus sect. Actinocephalus the ovule is orthotropus, bitegmic, and tenuicellate with a micropyle formed by the inner integument. The seeds are endotestal. The outer cell layer of the testa and the outer periclinal wall of the endotesta disintegrate during development. The endotegmen is tanniniferous. The outer layer of the tegmen becomes compressed and is no longer recognizable in the mature seed. The seeds are operculate.  相似文献   
56.
Plant material of 55 strains from 32 species ofSolanum sect.Solanum ( = sect.Morella) has been investigated for the content of steroidal alkaloids and sapogenins. The leaf-extracts of all species contain diosgenin resp. tigogenin or both together in considerable amount. On the contrary the characteristic steroidal alkaloid solasodine was absent in these samples. For 29 species the presence of steroidal sapogenins has been proved for the first time. In unripe fruits, however, solasodine could be detected in most of the species examined. New occurences of solasodine are reported for seven further species. These chemical results may contribute to a better comprehension of the difficult genusSolanum.—Ontogenetic studies on different organs ofS. atriplicifolium show the relationship between accumulation of steroidal compounds and plant maturity.  相似文献   
57.
Evolutionary relationships and infra- and interspecific variability within the species ofTulipa sect.Eriostemones Boissier were studied. Measurements of 35 morphological characters were used for principal component and canonical variate analyses. Crossing experiments and chromosome counts were carried out. Two axes of morphological variation were encountered within the principal component plot. Variation of subsect.Biflores was traced along one axis, the species of subsect.Australes as well asSaxatiles were found along the other axis. The nomenclature of names of subsect.Biflores was considered on the basis of their geography, specific morphological characteristics and polyploidy. Conspecificity of names of all species was tested based on both morphology and crossability.  相似文献   
58.
Asplenium sect. Thamnopteris or A. nidus L. complex is defined by the synapomorphic character peculiar to Aspleniaceae, an anastomosing vein near the margin of the simple lamina. Thus, it is easily recognizable and its monophyly is quite clear. In spite of its naturalness as the whole group, species delimitation is very confusing. Three species of sect. Thamnopteris, A. antiquum Makino, A. australasicum (J. Smith) Hooker and A. nidus L. have been recognized in Japan, but the naturalness of each species is still not clear because their morphology is too simple to find good qualitative taxonomical characters. In the present work, we examined the intraspecific variation of allozymes and rbcL sequences in the Japanese plants of sect. Thamnopteris and compared them with those from other paleotropical localities in order to recognize natural units in such morphologically simple plants. We found a large amount of genetic variation in this section and inferred that A. antiquum is a species of ancient origin, though morphologically it is not so different from other species of the sect. Thamnopteris. It was also discovered that the so called “A. australasicum” in Japan has a very different rbcL sequence from A. australasicum sensu Holttum, which is distributed in Australia and South Pacific Islands. Based on these molecular data, we described the Japanese “A. australasicum” as a new species, Asplenium setoi N. Murak. et Seriz. Received 9 September 1998/ Accepted in revised form 22 December 1998  相似文献   
59.
Mycena haushoferi, a new species of the section Intermediae collected in Bavaria, is described and compared with four other species of the sect. Intermediae known from the Northern Hemisphere and with M. cystidiosa and M. metuloidifera, two species of sect. Metuloidiferae. The five known species of Northern Hemisphere of section Intermediae are keyed out.  相似文献   
60.
The systematics of theGlaucescentes Carl, a poorly known neotropical section of the large genusPlagiochila, is revised based on a large set of gametophytic, sporophytic and chemical characters. Three species are recognized,P. buchtiniana Steph.,P. longispina Lindenb. and Gottsche andP. diversifolia Lindenb. and Gottsche, the latter with two chemotypes. Twelve binomina are reduced to synonymy. The species occur in montane regions of tropical America, especially in the northern and central Andes. In addition,P. longispina is newly reported from the Azores, where it was previously known asP. allorgei Herzog and Perss. TheGlaucescentes are excellently characterized by morphological and chemical features and are clearly separated from theContiguae Carl, a group often confused with theGlaucescentes. Morphologically, theGlaucescentes stand apart by the brown oil bodies, thinwalled inner capsule wall cells and partly unequally bispiral elaters. Chemically, they are characterized by the accumulation of partially hydrogenated bibenzylderivatives (longispinone, longispinol), 3-benzylphthalides and various flavonoids, and by the low production of terpenoids.Publication No. 142 of the Arbeitskreis Chemie und Biologie der Moose, Universität des Saarlandes, Saarbrücken.  相似文献   
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