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1.
Based on an analysis of results from experimental hybridization, the plants assigned byMunz toOenothera subg.Oenothera and subg.Raimannia, now divided into approximately 76 species, are referred to a single section,Oenothera. This section is in turn divided into five subsections:Euoenothera, Munzia, Raimannia, Emersonia, and an undescribed group of three species related toOenothera pubescens. Euoenothera is maintained in the traditional sense, and includes about 14 species of North America, widely naturalized elsewhere.Munzia consists of 45 species, comprising three series, and native to South America.Raimannia is restricted to a group of approximately 11 North American species.Emersonia comprises four rather heterogenous species of northern Mexico and southern New Mexico, of whichOenothera macrosceles, O. maysillesii, andO. organensis have been described. Within these four subsections, interspecific hybrids can be made in general, although plastid differentiation often leads to incompatibilities. With varying degrees of difficulty, hybrids were produced in all intersectional combinations involvingEuoenothera, Emersonia, Munzia, andRaimannia, the most difficult being those betweenEmersonia andRaimannia. Based on their habit and distribution,Emersonia species, and especiallyOenothera maysillesii, appear to resemble most closely the common ancestor of the section,Euoenothera andMunzia to have been derived from it or its common ancestor, andRaimannia perhaps to be more closely related to the phylogenetic branch that leads toEuoenothera.  相似文献   

2.
In the F2-progeny of hybrids from crosses betweenOenothera biennis orsuaveolens andOe. hookeri with theRenner-complexesalbicans andhhookeri, the development of callose pattern in meiocytes and megaspore tetrads is the same as in the F1 and the parentOe. hookeri. During the development of the megaspore tetrads and the embryo sacs primary and secondary heteropolarity as well as homopolarity is observed. Estimates for the initial frequency of homo- and heteropolar tetrads at the end of the degeneration of megaspores in the tetrads immediately before the start of embryo sac development could be calculated. The F2-plants can be arranged in three groups, distinguished by the frequency of the two polarity types. One of these groups behaves similar to the parentOe. hookeri, the two others have more homopolar tetrads. The segregation can be interpreted as recombination of genes, which influence the development of the polarity in the ovules. This is possible by crossing-over of genes between the twoRenner-complexes of the hybrid.  相似文献   

3.
Summary The chloroplast DNAs (cpDNAs) of Oenothera berteriana and Oe. odorata (subsection Munzia) were examined by restriction endonuclease analysis with Sal I, Pvu II, Kpn I, Pst I, Hind III, and Bam HI. The fragment patterns show that these cpDNAs have all 133 restriction sites in common as well as a lot of individual bands. Nevertheless the cpDNAs of the two species can be distinguished by distinct differences in size between a small number of fragments. The 42 cleavage sites produced by Sal I, Pvu II and Kpn I were mapped on the circular cpDNAs. This was achieved by an approach which combined experimental and mathematical procedures. The overall serial order of the fragments was found to be the same for both cpDNAs. The size differences of individual fragments in the Sal I, Pvu II and Kpn I patterns between Oe. berteriana and Oe. odorata cpDNA are located within five regions scattered along the plastid chromosome. Two of these regions have been localized in the larger and one in the smaller of the two single-copy parts of the cpDNA molecule. The remaining two overlap the borders between the large single-copy and each of the duplicated parts of the molecule. The positions of distinct restriction sites are altered among the two Oenothera plastome DNAs by 0.02–0.4 MDa (30–600 base pairs). These alterations probably result from insertions/deletions.Abbreviations cpDNA chloroplast, plastid DNA - Oe. Oenothera - MDa Megadalton - rRNA, rDNA ribosomal RNA, DNA Dedicated to Professor Berthold Schwemmle, Tübingen, on the occasion of his 60th birthday  相似文献   

4.
Summary Inheritance of the falcifolia syndrome is explained by the hypothesis that this developmental disturbance is caused by the interaction of a non-chromosomal determinant (sigma) of Oenothera suaveolens with a complementary determinant (lambda) of O. lamarckiana when these two species are crossed. Localization of the determinants in the cell, the mechanism of their expression, and their molecular nature have not been established. Somatic segregation within the hybrids may lead to a separation of the two components, as suggested by the different reactions of sister plants in backcross tests and on selfing. The present paper presents results showing that in rare cases the fal determinants may be eliminated from the hybrid's cytoplasm. Thus, plants are produced that are phenotypically identical with the original parental strains but in crosses react like species that lack such determinants.  相似文献   

5.
Oenothera nutans, common to the Appalachian Mts between 650 and 1 700 m altitude, was investigated cytogenetically and taxonomically. The species is permanently structurally heterozygous. It consists of two genomes of the B-type which are more or less indistinguishable phenotypically. Nearly all of the strains investigated possess a self-incompatibility factor in one of the two complexes. Both complexes show a close relationship to the predominantly homozygousO. grandiflora, a native of the southern lowlands.O. nutans andO. grandiflora possess the same plastid type, plastome III. Probably,O. nutans evolved by an accumulation of reciprocal translocations within an originally structurally homozygous population, which must be regarded ancestral to the present forms ofO. grandiflora.  相似文献   

6.
The homozygousOenothera hookeri Torr. etGray shows the typical pattern ofOnagraceae with ± callose on the external walls of megaspore mother cells and tetrads. Megasporogenesis is heteropolar, and the micropylar megaspore is the mother-cell of the 4-celled embryo sac. The complex-heterozygousOenothera biennis L. during megasporogenesis generally has callose not on the external cell walls but only on the transversal walls of the tetrad. In 95% of the ovules both the external chalazal and the micropylar megaspores develop to embryo sac mother-cells. Megasporogenesis is homopolar, and competition between two developing embryo sacs for nutrition in the ovule occurs. The embryo sac with the stronger genotype wins the race against the other one. Polarity phenomena during ontogeny of the female gametophyte are related to nutritional supply and hormonal induction from the ovule. The introduction of a developmental-physiological point of view into the discussion about the evolution of the embryo sac inOnagraceae is therefore justified.Stipendiatin der Alexander von Humboldt-Stiftung 1974/76.  相似文献   

7.
Wolfgang Hachtel 《Planta》1981,151(4):299-303
Reciprocal differences in the rates of chlorophyll (Chl) formation during early stages of greening are observed in hybrid seedlings with identical genomes derived from reciprocal crosses between Oenothera berteriana (=villaricae) and Oe. odorata (=picensis), subgenus Munzia. In the presence of levulinic acid (LA), a competitive inhibitor of 5-aminolevulinic acid (ALA) dehydratase, ALA accumulated in the cotyledons and chlorophyll production was reduced in a stoichometric ratio. Accumulation of both Chl in untreated tissue and of ALA in seedlings incubated with LA is much more rapid in cotyledons with berteriana plastids than in those with odorata plastids. No difference was found between the inhibitor constants for LA of ALA dehydratase extracted from seedlings with either berteriana or odorata plastids. ALA formation is not limited by the availability of possible precursors. ALA dehydratase and the porphobilinogenase complex (PBGase) are present in abundance and in equal amounts in cotyledons with either berteriana or odorata plastids. It is concluded that the different capacities of the ALA synthesizing system fully account for the different rates of Chl formation in the seedlings with identical genomes and different plastid types.Abbreviations Chl chlorophyll - ALA 5-aminolevnlinic acid - ALAD 5-aminolevulinic acid dehydratase - LA levulinic acid - PBG porphobilinogen - PBGase porphobilinogenase - Oe Oenothera - bert berteriana - od odorata - Pl plastids  相似文献   

8.
A Japanese black cow from a farm in Gunma prefecture showed pyrexia, anorexia and depression. An autopsy revealed hepatic lesions consisting of numerous approximately spherical pale lesions scattered about on the surface and cut parts. The inflammatory lesions were observed in the right lobe of the lung. A part of the trachea was whitish and thickened. Histologically, necrotic foci were observed throughout most of the liver with fungal proliferation about the blood vessels. The lesions of the lung were seriously exudative and the fungus was also present in some of the bronchiole and on bloodvessel walls. Mortierella wolfii was isolated from the liver. The hyphae in the liver were identical in appearance with those seen in the tissues of rabbits experimentally inoculated with M. wolfii.This report is the first case of M. wolfii infection in Japan  相似文献   

9.
Summary The falcifolia (fal) syndrome is a malformation characterized by shoot sectors with sickle-shaped leaves, which appears in hybrids between Oenothera suaveolens and O. lamarckiana and shows a non-chromosomal inheritance of a previously undescribed type. The determinants, their location in the cell, and the mechanism of their expression are unknown. The defect is the result of a cross in which mixing of two different cytoplasms occurs, without the usual predominantly maternal inheritance. F1 progeny of reciprocal crosses show a quantitative difference in the frequency and degree of expression of the fal character. When the F1 progeny are backcrossed to the parents, the percentage of fal is high in crosses to O. suaveolens and low in those to O. lamarckiana. This manner of transmission is observed regardless of whether the hybrid is used as seed or pollen parent or shows a normal or fal phenotype. F2 generations from F1 plants having either a normal or a fal phenotype always include a certain percentage of fal plants, although the latter generally produce a higher percentage of fal progeny. If a second backcross is carried out, plants that produce normal progeny on self-pollination behave differently from those that produce some fal off-spring when selfed. The latter are similar to the F1 with regard to the transmission of the fal trait. Plants of the F1B1 yielding normal progeny upon selfing produce normal progeny in the F1B2 if the parent to which they are backcrossed is the same as in the first backcross; if the parents of the first and second backcross differ, a high percentage of fal offspring is obtained. Again, whether the hybrid is used as seed or pollen parent is not relevant. Exceptions to this behaviour have been observed only rarely in that the character of the penultimate cross is retained. There is some evidence of somatic segregation of the fal determinants, since sister plants may react differently; this suggestion is supported by comparing the progenies of different branches of a self-pollinated fal plant of the F1 generation.Abbreviations F1, F2, F3, F4 First through fourth filial generation, obtained by self-pollination - F1B1 First backcross generation, i.e. the F1 was backcrossed to one of the original parents - F1B2 Second backcross generation, i.e. the F1B1 was backcrossed to one of the original parents - F1B3 Third backcross generation, i.e. the F1B2 was backcrossed to one of the original parents - (F1B1)D1 Descendants obtained by self-pollination of a F1B1 plant; further generations obtained by self-pollination are designated as D2, D3, D4 - (F1B1)D1B1 Descendant or generation obtained by a backcross of the D1 of an F1B1. Backcrosses of the D2 and D3 are designated mutatis mutandis - (F1B1)D1B2 Generation obtained by a backcross of the (F1B1)D1B1  相似文献   

10.
The two generaPlectranthus andIsodon are compared and found to be very dissimilar.Isodon ist considered to be misplaced inOcimeae subtribePlectranthinae and apparently is more closely related to subtribeHyptidinae. The disjunct genusRabdosiella is compared to these two genera and regarded to be polyphyletic. The AfricanR. calycina (Benth.)Codd is returned toPlectranthus and calledP. calycinus Benth., while the AsianR. ternifolia (D. Don)Codd is placed inIsodon sect.Pyramidium and calledI. ternifolius (D. Don)Kudo.  相似文献   

11.
Interspecific hybridizations were made between species of theE. semicostatus group, viz.,E. semicostatus (Nees exSteud.)Meld.,E. validus (Meld.)B. Salomon,E. abolinii (Drob.)Tzvel., andE. fedtschenkoi Tzvel., and species of theE. tibeticus group, viz.,E. pendulinus (Nevski)Tzvel.,E. tibeticus (Meld.)Singh,E. shandongensis B. Salomon, andE. gmelinii (Ledeb.)Tzvel., as well as among species within theE. tibeticus group. All species are tetraploid (2n = 4x = 28) and possess SY genomes. Meiotic pairing data from 24 hybrids involving 17 interspecific combinations are presented. The average number of chiasmata per cell ranged from 17.91 to 26.20 in hybrids within theE. tibeticus group, compared with 7.26 to 22.04 in hybrids between the two species groups. Despite the extensive collection of cytological data, there was no definite evidence for confirming or disproving the separate existence of the two groups.  相似文献   

12.
The nomenclatural history of the generic nameParmeliopsis is reviewed. Its correct citation is found to beParmeliopsis (Nyl. exStizenb.)Nyl., dating from 1866, not 1869 as commonly cited, withP. placorodia (Ach.)Nyl. as holotype species. There is consequently no nomenclatural problem to the adoption ofForaminella Fricke Meyer, typified byF. ambigua (Wulfen)Fricke Meyer for theParmeliopsis species with falcate conidia. A synopsis of the nomenclature of the North American and European species of both these genera is included.  相似文献   

13.
The green algaTrebouxia aggregata (Archibald)Gärtner (Chlorellales) and the procaryotic blue-green alga (cyanobacterium)Gloeocapsa sanguinea (C. Agardh)Kütz. emend.Jaag (Chroococcales) are reported to be the phycobionts inEuopsis granatina (Sommerf.)Nyl. (Lichinaceae). The ultrastructure of the two organisms, studied in the lichen thallus, is described.
Frau Prof. Dr.Elisabeth Tschermak-Woess zu ihrem 70. Geburtstag gewidmet.  相似文献   

14.
The vegetation and fire history of few coastal sites has been investigated in the Mediterranean region so far. We present the first paleoecological reconstruction from coastal Sicily, the largest island in the Mediterranean Sea. We analysed pollen and charcoal in the sediments of Biviere di Gela, a lake (lagoon) on the south coast of Sicily. Our data suggest that the area became afforested after a marine transgression at ca. 7200 cal b.p. (5250 b.c.). Build-up of forest and shrublands took ca. 200–300 years, mainly with the deciduous trees Quercus, Ostrya and Fraxinus. Juniperus expanded ca. 6900 cal b.p. (4950 b.c.), but declined again 6600 cal b.p. (4650 b.c.). Afterwards, evergreen trees (Q. ilex-type and Olea) became dominant in the forest and Pistacia shrublands were established. Forest and shrubland reached a maximum ca. 7000–5000 cal b.p. (5050–3050 b.c.); subsequently forest declined in response to human impact, which was probably exacerbated by a general trend towards a more arid climate. During the Neolithic, fire was used to open the landscape, significantly reducing several arboreal taxa (Q. ilex, Fraxinus, Juniperus) and promoting herbs and shrubs (Achillea, Cichorioideae, Brassicaceae, Ephedra). Final forest disruption occurred around 2600 cal b.p. (650 b.c.) with the onset of the historically documented Greek colonization. We conclude that the open maquis and garrigue vegetation of today is primarily the consequence of intensive land-use over millennia. Under natural or near-natural conditions arboreal taxa such as Q. ilex, Olea and Pistacia would be far more important than they are today, even under the hot and rather dry coastal conditions of southern Sicily.  相似文献   

15.
A phylogenetic analysis of the familySphaerophoraceae (Caliciales, lichenized ascomycetes) has resulted in a new generic classification. Notes on character evolution are given. The generaSphaerophorus s. str.,Bunodophoron andLeifidium, gen. nov., are accepted.Pleurocybe andPseudosphaerophorus are considered synonyms ofBunodophoron andThysanophoron is considered synonym toSphaerophorus. The following new combinations are proposed:Bunodophoron coomerense (Ohlsson)Wedin,B. diplotypum (Vain.)Wedin,B. dodgei (Ohlsson)Wedin,B. flaccidum (Kantvilas & Wedin)Wedin,B. formosanum (Zahlbr.)Wedin,B. imshaugii (Ohlsson)Wedin,B. insigne (Laurer)Wedin,B. kinabaluense (M. Satô)Wedin,B. macrocarpum (Ohlsson)Wedin,B. madagascareum (Nyl.)Wedin,B. microsporum (Ohlsson)Wedin,B. murrayi (Ohlsson)Wedin,B. notatum (Tibell)Wedin,B. ohlssonii (Wedin)Wedin,B. patagonicum (C. W. Dodge)Wedin,B. ramuliferum (I. M. Lamb)Wedin,B. scrobiculatum (C. Bab.)Wedin,B. tibellii (Wedin)Wedin,B. whakapapaense (Wedin)Wedin, andLeifidium tenerum (Laurer)Wedin.  相似文献   

16.
Multivariate analysis of vegetative and reproductive characters was used to examine morphological relatedness amongAntennaria alborosea A. E. Porsild,A. corymbosa E. Nels.,A. marginata Greene,A. microphylla Rydb.,A. parvifolia Nutt.,A. rosea Greene, andA. umbrinella Rydb. Both pistillate and staminate plants were examined. Some of the characters examined were variable in one species, but stable in another (i.e., presence or absence of papillae on the achenes). Our analyses indicate that the seven species are morphologically distinct. It is hypothesized that theA. rosea agamic complex arose through hybridization amongA. corymbosa, A. microphylla, A. umbrinella, and possiblyA. dioica (L.)Gaertn. However, hybridization between the three former species and others, as well as their subsequent morphological responses to different environmental conditions causes confusion in recognizing the taxa.Antennaria angustifolia Rydb.,A. arida E. Nels.,A. confinis Greene,A. scariosa E. Nels.,A. foliacea humilis Rydb.,A. concinna E. Nels., andA. viscidula E. Nels. are considered to represent F 1 hybrids.  相似文献   

17.
Prof. Dr. O. Renner 《Planta》1956,47(3):219-254
Zusammenfassung Neu beschrieben werdenOenothera biennis var.angustifolia von Mannheim und die heterogameOe. nuda aus dem Bas Dauphiné.Eine im Gebiet der oberen Loire eingebürgerte Form derstrigosa-Gruppe wird als derOe. hungarica Borb. (Oe. Bauri Boedijn) nahestehend, wenn nicht mit ihr identisch erkannt.Zur Kenntnis vonOe. parviflora L.,ammophila Focke,syrticola Bartlett,rubricuspis, nova von Zinna, sowie der synthetischen Artenalbipercurva, Issleri (=rubicurva), Hölscheri (=rubiundata) wird einiges Neue beigebracht.AusOe. nova von Zinna (quaerens·paravelans) geht viel häufiger als ausOe. Lamarckiana eine Translokationsmutante vomrubrisepala-Typus hervor. Auch in der Nachkommenschaft der (biennis x Zinna) albiparavelutina ist einerubrisepala entstanden, wie sie bei (biennis x Lamarckiana) albivelutina noch nie beobachtet worden ist. Oe. nova von Zinna ist nicht, wie bisher vermutet, identisch mitOe. erythrosepala Borb. (die zu,Lamarckiana gehört) und wird in Zukunft alsOe. coronifera bezeichnet werden.Die Entstehung neuer Arten durch Kreuzung wird wieder erörtert.Auf die verschiedene Lage der Taxonomie der Oenotheren in Europa und in den Vereinigten Staaten wird hingewiesen.Die Chromosomenformeln der europäischen Komplexe werden mit denen der nächststehenden amerikanischen verglichen.Mit 17 TextabbildungenDer Deutschen Forschungsgemeinschaft bin ich für Unterstützung verpflichtet. Elisabeth Schiemann proleptisch zum 75. Geburtstag gewidmet.  相似文献   

18.
Silene thebana Orph. exBoiss. is transferred as a subspecies toS. fabaria (L.)Sm., resulting in the new combinationS. fabaria (L.)Sm. subsp.thebana (Orph. exBoiss.)Melzh. The chromosome count of 2n = 24 is recorded for the first time for this taxon.Dedicated to Prof. DrK. H. Rechinger on the occasion of his 80th birthday, 16th October 1986.  相似文献   

19.
Verrucaria schaereri (Fr.)Nyl. is accorded generic status asPlacocarpus Trev. emend.O. Breuss. The main differences between the two genera concern the thallus anatomy and the spores which are halonate inPlacocarpus. The following new combinations are proposed:Placocarpus schaereri (Fr.)O. Breuss andPlacidiopsis cinerascens (Nyl.)O. Breuss.  相似文献   

20.
(1) The ability to produce cephalodia is usually a genus-specific character in lichens. (2)Lecidea shushanii Thoms., is a member of the genusTephromela, closely related toT. aglaea. It is not clear, whether or not the cephalodia of this taxon are true cephalodia or colonies of epiphytic cyanobacteria and whether or notLecidea shushanii is an independent species. (3)Lecidea dovrensis Nyl., is, in contrast to the traditional concept, not conspecific withLecidea alpestris Sommerf., but an earlier name forLecidea pallida Th. Fr. (4)Lecidea dovrensis is described in some detail. Chemically the species is characterized by the presence of isousnic acid (previously unknown in lecideoid lichens). It is restricted to areas north of the 60th parallel with an oceanic climate. (5) In connection with the attempt to clarify the taxonomic relationships ofLecidea dovrensis, figures of ascus apical structures of the following species are given (marked by an asterisk are genera where we found discrepancies with published data):Austrolecia antarctica, Catillaria chalybeia, Lecidea alpestris, L. caesioatra, L. limosa, Lecidoma demissum, Koerberiella wimmeriana, Micarea assimilata, M. crassipes, M. melaenida, M. prasina, Pilophorus robustus, Placodiella olivacea, Placolecis opaca, Porpidia trullisata, Protoblastenia rupestris, Psilolechia lucida, Psorula rufonigra, Squamarina gypsacea, Xanthopsorella texana. (6) Among crustaceous lichens we find no groups related toLecidea dovrensis. We supportTimal's concept of including this species in the genusPilophorus. Pilophorus, as well asLecidea dovrensis is characterized by the same ascus type, by a similar structure of thallus, cephalodia, paraphyses, and ascocarp (although there is no pseudopodetium developed inLecidea dovrensis), and the presence of isousnic acid. In addition, both taxa are restricted to cool oceanic climates and non-calciferous substrates. The following combination is proposed:Pilophorus dovrensis (Nyl.)Timdal, Hertel & Rambold, comb. nova. (7) The species of theLecidea alpestris-group form an independent genus, probably near toAustrolecia Hertel.
Frau Prof. Dr.Elisabeth Tschermak-Woess zu ihrem 70. Geburtstag gewidmet.  相似文献   

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