Kritische Bemerkungen zuPapaver bracteatum Lindl.

Zusammenfassung Form und Behaarung des Kelches und die Farbe der Kronblätter werden als wichtigste diagnostische Merkmale vonPapaver bracteatum Lindl. beschrieben. Sie erlauben dessen eindeutige Unterscheidung von verwandten Taxa. Dagegen sind die Brakteen, denen in der Literatur große Aufmerksamkeit geschenkt wird, für eine Trennung ungeeignet.

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Summary Shape and pubescence of calyx and colour of petals are described as important diagnostic characters ofPapaver bracteatum Lindl. They allow a correct separation from related taxa. In contrast to the view found in literature the bracts are not essential to discrimination.

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Wir danken Herrn Prof. Dr. K.Mothes herzlich für sein Interesse am Fortgang unserer Untersuchungen und Herrn Dr. K.Werner vom Institut für Systematische Botanik und Pflanzengeographie der Universität Halle für kritische Diskussionen bei der Abfassung des Manuskriptes.     

Notes on Campanula dimorphantha (Campanulaceae)

The correct name of the species currently called Campanula canescens or C. benthamii in Asian floristic literature is shown to be C. dimorphantha . The distribution of the species is mapped and its occurrence in both Africa and Asia is confirmed. Both cleistogamous and normal flowers may be produced in plants of C. dimorphantha . The adaptive significance of this dimorphism is briefly discussed.     

Floral venation patterns in Siphocampylus (Campanulaceae)

Siphocampylus is a neotropical genus that comprises 221 species distributed from Costa Rica to Argentina and in the Greater Antilles. Twenty-eight species have been reported from Brazil, mainly occupying mountainous terrain. The floral venation patterns and the origin of the hypanthium in eight Brazilian species, including three varieties, are described. Eleven ovarian vascular bundles depart from the siphonostele or receptacular stele: five of these bundles result from sepalar and staminal adnation and are alternate to five petalar bundles; the remaining bundle is central carpellary. The staminal bundles diverge from the sepalar bundles at the sinus, while the carpellary bundles form a cross, resulting in four ventral bundles; two of these feed the ovules; the other two feed the style. Apparently, the dorsal carpellary bundles diverge at the same site and then ramify profusely. The venation pattern observed is unprecedented in Siphocampylus and is quite different from other reports on genera of Campanulaceae. Further, these findings suggest that the origin of the hypanthium is appendicular, increasing knowledge of venation in this group, thus providing data for phylogenetic considerations.     

Pollination mechanisms in sixCampanula species (Campanulaceae)

Pollination mechanisms within the genusCampanula were studied. Tests were undertaken to examine whether in vitro culture of pollen grains can serve as a useful tool for understanding the self- and cross-pollination mechanisms among species. Characteristics of pollen germination were interpreted in relation to mating system and floral biology. Four annual species (Campanula kremeri, C. dichotoma, C. afra, C. lusitanica), and two perennial species (C. rotundifolia andC. persicifolia) were investigated. In the annual species pollen germinability is controlled by (1) the age of pollen and/or (2) in what position pollen is deposited around the style. Correlations were found between pollen germinability and mating system in three of the four annual species. No correlations were found either between germinability and age of pollen or position on the style in the perennial species. Pollen germinability reached its maximum in the middle of the male phase in all species, except forC. dichotoma, which had a decreasing germinability throughout anthesis. The germinability was lowest at the time of stigma receptivity for all species except forC. persicifolia, where the stigma did not develop as long as pollen remained on the style. The pollen collecting hairs and pollen removal have been found to play an important role controlling the stigma development, thus affecting self-pollination. This was especially pronounced inC. persicifolia. Further studies will be undertaken to elucidate factors influencing pollination within the genusCampanula.     

A new species ofAdenophora (Campanulaceae) from Korea

Adenophora erecta S. Lee, J. Lee et S. Kim, is described as a new species from an open north-facing mountain slope on the coast of Sukpo-Dong, Ullungdo Is., Kyungsangbukdo, Korea. This species resemblesA. remotiflora Miq., but is well separated by having the leaves compactly arranged along the upper part of the stem, condensed raceme, distinct veins on the corolla and especially shallow dome-shaped epigynous nectar disc.     

Another perspective on cytoevolution in Lobelioideae (Campanulaceae)

The Lobelioideae is a cosmopolitan group whose cytoevolution is discussed on a model of primitively high diploid chromosome numbers, in which x = 14 is relatively plesiomorphic and x = 21 may be even more plesiomorphic. This model is suggested from the high frequency of lobelioid genera with x = 14, the probably plesiomorphic condition of x = 17 in the sister group Campanuloideae (Campanulaceae), and the primitive x = 15 in Stylidiaceae (Campanulales). It contrasts with that for a primitive x = 7 and paleopolyploidy to higher chromosome numbers. In our analysis, the genus Lobelia shows three broad cytoevolutionary groups, which probably have phylogenetic and infrageneric taxonomic significance: (1) woody diploids with x = 21 in Chile and woody diploids with x = 14 in Africa, Asia, and Hawaii; (2) herbaceous diploids with several series of dysploid chromosome numbers n = 19, 13, 12, 11, 10, 9, 8, 7, 6, mainly in Africa and Australia; (3) widespread and speciose herbaceous taxa based on a very derived n = 7, with recent frequent euploid rises (neopolyploidy) at or below the species level in subgenus Lobelia and allied or segregate genera. Other woody and herbaceous lobeliad genera have comparable cytoevolutionary patterns. New chromosome counts for Australian Lobelia, Pratia, and Isotoma illustrate the last two cytoevolutionary groups.     

Crossing experiments within theCampanula dichotoma group (Campanulaceae)

Four supposedly closely related taxa were crossed artificially to test for hybridization barriers. Intra- as well as inter-specific crossings were made. The intra-specific crossings resulted in a high portion of viable hybrids, whereas hybridization barriers were found in all inter-specific combinations except one. The hybrids were non-viable at different levels, viz., (1) no seeds germinated, (2) seeds formed lethal chlorotic seedings, or (3) seeds formed chlorophyllous seedlings which survived the cotyledonary stage, but developed into intermediate forms with low pollen production and/or a strongly reduced pollen viability. Crossings betweenCampanula afra and any of the other three taxa resulted in a non-viable progeny. The crossing capacity amongC. occidentalis, C. kremeri, andC. dichotoma varied. Combinations with large-flowered maternal taxa and small-flowered paternal ones usually failed, whereas a high number of the reciprocal crossings produced hybrids which survived the cotyledonary stage. The hybrid plants varied in pollen viability and pollen production, however. It is concluded that theCampanula dichotoma group should be treated as comprising four distinct species.     

New species of Wahlenbergia (Campanulaceae) from Africa

Five new species of Wahlenbergia are described and illustrated: W. tetramera from the high Drakensberg in Natal, W. petraea from Burundi, and W. marunguensis, W. polyphylla and W. malaissei from Zaire.     

Hybridization between Triodanis perfoliata and Triodanis biflora (Campanulaceae)

Experimental hybridizations betweenTriodanis biflora (Ruiz & Pavon) Greene andT. perfoliata (L.) Nieuwland result in vigorous offspring in the F₁ and F₂ generations as well as in backcrosses. Field studies of natural populations indicate a gradient between the two taxa with many individuals resembling the experimental hybrids. A partial isolating mechanism due to cleistogamy inT. biflora enables plants of that morph to be easily identified.Triodanis biflora is reduced toT. perfoliata var.biflora (Ruiz & Pavon) Bradley, comb. nov.     

A new species of Cyananthus (Campanulaceae) from Nepal

A new species, Cyananthus himalaicus from Gurjakhani, Nepal is described and illustrated, and its relationship with C. cordifolius and C. pedunculatus is discussed.     

Reproductive biology ofWahlenbergia (Campanulaceae) endemic to Robinson Crusoe Island (Chile)

The reproductive biology ofW. berteroi, W. fernandeziana, and a putative hybrid betweenW. fernandeziana andW. grahamiae, endemic to Robinson Crusoe Island (Juan Fernández archipelago, Chile) was studied. Flowers are hermaphroditic, protandrous, offer nectar, and exhibit secondary pollen presentation involving pollen collecting hairs on the style. These features imply allogamy and biotic pollination. However, male and female phases overlap and no effective pollinators were observed. Experimental data indicate these taxa are self-compatible and facultatively autogamous, a conclusion also suggested by the pollen/ovule ratios. Selfing is accomplished when the stigmatic lobes reflex and touch the style, except forW. berteroi where they do not reflex completely. Autogamy is accomplished in the latter when pollen grains deposited on the inner surface of the corolla throat by the pollen brush are gathered by stigmatic lobes when shaken by wind. The degree of autogamy, and perhaps self-compatibility, seems to be inconstant, as implied by the variable natural seed set (overall range 21–188 seeds per fruit). A mixed mating system — primarily outcrossing/entomophilous, but also autogamous — must have been present in the continental ancestors of these taxa. Autogamy promoting self-fertilization is important now — on an island with scarce pollinators — and in the past — when the first founders arrived.     

A new Campanula (Campanulaceae) from east Anatolia, Turkey

Campanula demirsoyi A. Kandemir (Campanulaceae) is described and illusturated from a localised area of Erzincan province. It is closely allied to C. hedgei Davis and C. coriacea Davis. Diagnostic morphological characters are discussed and compared with those of related taxa.     

Morphological, anatomical and palynological studies on Asyneuma michauxioides (Campanulaceae)

The morphological, anatomical and palynological features of Asyneuma michauxioides (Boiss.) Damboldt (Campanulaceae) were investigated. This species is an East Mediterranean Floristic Element and an endemic in Turkey. In anatomical studies, cross-sections of the root and stem were examined and demonstrated by photographs. It has conspicuous endodermis in which the Casparian bands are indistinct in the stem. According to the result of this study, it was found that pollen grain of this taxon was 3-porate sometimes 4-porate and oblate-spheroidal. Its structure was tectate and sculpture was small granules and pits with densely spaced spinules. The seeds of the taxon were eliptic to ovate in shape, laterally compressed, brown to light brown in colour, glabrous and shiny.     

Jasione sphaerocephala sp.nov. (Campanulaceae) from Italy

Jasione sphaerocephala Brullo, Marcend et Pavone sp.nov. is described from Calabria, S Italy. It grows in rocky places and has some resemblance to J. laevis and J. montana. The chromosome number is 2n = 14.     

Nectar spur evolution in the Mexican lobelias (Campanulaceae: Lobelioideae)

Phylogenetic studies are often hampered by the independent evolution of characters that may potentially obscure relationships. The adaptive significance of the nectar spur and its evolution within the Mexican lobeliads (Campanulaceae) is considered here. The taxonomic delimitations of Heterotoma from the Mexican species within the genera Lobelia and Calcaratolobelia were tested. Independent molecular data were gathered to determine whether the Mexican spurred lobeliads should be treated as distinct genera. The internal transcribed spacer (ITS) region from 18-26S nuclear rDNA and chloroplast DNA from the 3' trnK intron were sequenced from 14 representative species. Our data suggest that Heterotoma, as originally conceived, is a good evolutionary unit within Lobelia and that the presence of a nectar spur is an important morphological character that can be used in defining phylogenetic position. This study also suggests that morphological changes associated with hummingbird pollination have evolved more than once in the Mexican lobeliads, from small blue-flowered, insect-pollinated relatives.     

The pollination biology of Burmeistera (Campanulaceae): specialization and syndromes

The floral traits of plants with specialized pollination systems both facilitate the primary pollinator and restrict other potential pollinators. To explore interactions between pollinators and floral traits of the genus Burmeistera, I filmed floral visitors and measured pollen deposition for 10 species in six cloud forest sites throughout northern Ecuador. Nine species were primarily bat-pollinated (84-100% of pollen transfer); another (B. rubrosepala) was exclusively hummingbird-pollinated. According to a principal components analysis of 11 floral measurements, flowers of B. rubrosepala were morphologically distinct. Floral traits of all species closely matched traditional ornithophilous and chiropterophilous pollination syndromes; flowers of B. rubrosepala were bright red, lacked odor, opened in the afternoon, and had narrow corolla apertures and flexible pedicels, which positioned them below the foliage. Flowers of the bat-pollinated species were dull-colored, emitted odor, opened in the evening, and had wide apertures and rigid pedicels, which positioned them beyond the foliage. Aperture width appeared most critical to restricting pollination; hummingbirds visited wide flowers without contacting the reproductive parts, and bats did not visit the narrow flowers of B. rubrosepala. Aperture width may impose an adaptive trade-off that favors the high degree of specialization in the genus. Other floral measurements were highly variable amongst bat-pollinated species, including stigma exsertion, calyx lobe morphology, and pedicel length. Because multiple species of Burmeistera often coexist, such morphological diversity may reduce pollen competition by encouraging pollinator fidelity and/or spatially partitioning pollinator's bodies.     

Life history variation in Campanula americana (Campanulaceae): population differentiation

Genetic variation in life history traits has important consequences for life-history evolution. Here we report the results of a greenhouse experiment investigating the broad sense genetic basis of variation in life history traits within and among five populations of Campanula americana distributed along a latitudinal gradient. The populations exhibit differentiation for a number of morphological traits (seed weight, number of branches, final plant size, number of capsules) and the phenological traits, days to emergence, days to bolting, the onset of flowering, and the duration of flowering. Families within populations differed only in days to emergence and seed weight. These results suggest that the life history differences among populations are genetically based. In addition, two life history types—winter annuals and biennials—have previously been reported from natural populations of Campanula americana. This experiment identified a third type—summer annuals from the Florida population.     

Pollination,biogeography and phylogeny of oceanic island bellflowers (Campanulaceae)

We studied the pollination biology of nine island Campanulaceae species: Azorina vidalii, Musschia aurea, M. wollastonii, Canarina canariensis, Campanula jacobaea, Nesocodon mauritianus, and three species of Heterochaenia. In addition, we compared C. canariensis to its two African mainland relatives C. eminii and C. abyssinica. We asked to what extent related species converge in their floral biology and pollination in related habitats, i.e. oceanic islands. Study islands were the Azores, Madeira, Canary Islands, Cape Verde, Mauritius, and Réunion. Information about phylogenetic relationships of these species and their relatives were gathered from atpB, matK, rbcL and trnL-F regions, building the most complete phylogeny of Campanulaceae to date. Six of the island bellflower species were bird-pollinated and two (A. vidalii and M. aurea) were lizard-pollinated. Insects also visited some of the species, and at least C. jacobaea had both insect- and self-pollination. Several morphological traits were interpreted as adaptations to bird and lizard pollination, e.g. all had a robust flower morphology and, in addition, bird-pollinated species were scentless, whereas lizard-pollinated species had a weak scent. These examples of vertebrate pollination evolved independently on each island or archipelago. We discuss if these pollination systems have an island or mainland origin and when they may have evolved, and finally, we attempt to reconstruct the pollinator-interaction history of each species.     

新疆党参的花部综合征与次级花粉呈现

次级花粉呈现是植物提高花粉输出和接受的效率与准确性以及促进异交的一种繁殖策略.新疆党参(Codonopsis clematidea)具有典型的次级花粉呈现特性.本文采用野外观测、授粉实验与室内显微观测等方法,对该物种的花部综合征及其次级花粉呈现过程进行了详细观测,并对这些特征的适应意义进行了探讨.结果表明:新疆党参钟状下垂的蓝色花冠及黑黄色蜜腺,不仅避免了雨水冲刷雌雄蕊、稀释花蜜以及风移出花粉等不利影响,还增加了对传粉者的吸引,延长了花粉活力及柱头可授性持续时间.次级花粉呈现属于亚顶端花柱呈现者,呈现机制为沉积机制.该特性限制了单个传粉者带走的花粉量,延长了花粉呈现时间,使更多传粉者参与传粉过程,增加了雄性适合度.其雄性先熟及雌雄蕊空间位置变化,避免了雌雄功能干扰,为传粉者取食花蜜、输出花粉以及柱头接受异源花粉提供了通道和机会.其泛化传粉系统的主要传粉昆虫为林野熊蜂(Bombus silvarum)、草地熊蜂(B.paradoxus)和树长黄胡蜂(Dolichovespula sylvestris),其较长的单花花期(6 d左右),昆虫访花高峰期与花粉活力最高时期及柱头最佳授粉期相吻合,以及较大的泌蜜量、较高的花蜜糖浓度和较长的泌蜜时间等特征,可提高传粉者的访花频率,增加成功传粉的机会和传粉效率.在气候多变的天山山区,该物种特殊的花部综合征和次级花粉呈现机制对提高其传粉效率并促进异交繁殖成功具有重要意义.