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Margrethe Serek - One of the best experts on this subject based on the ideXlab platform.
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an efficient protocol for agrobacterium mediated transformation and regeneration of Campanula medium canterbury bells based on leaf disc explants
Plant Cell Tissue and Organ Culture, 2020Co-Authors: Christian Gehl, Guo Li, Margrethe SerekAbstract:Campanula medium is an important ornamental plant known for its blue and bell-shaped flowers and a good model for studying flower colour formation and modification. The major outstanding obstacle preventing the developing of genetic modification and improvements in C. medium is a missing transformation method. For the first time, an effective and reliable in vitro regeneration and Agrobacterium-mediated transformation system has been established in this study. Different types and combinations of plant growth regulators (PGRs) were investigated for shoot regeneration by using leaf explants from three different cultivars. A high regeneration rate (50% for cv. ‘Blue double’, 58% for cv. ‘White double’ and 44% for cv. ‘Pink double’) was achieved on MS-based medium supplemented with 11.5 μM thidiazuron (TDZ) and 2.3 μM 1-naphthaleneacetic acid (NAA). In total, the Agrobacterium strains ABI, AGL1 and GV3101:pMP90, transformed with a binary plasmid harbouring NPTII and GFP gene cassettes, were evaluated for plant transformation, while various factors affecting the transformation efficiency were also identified. The highest transformation rate of about 22% was obtained from explants pre-cultured on regeneration medium and infected with AGL1. However, transgenic shoots were produced by all three Agrobacterium strains studied and confirmed by PCR and GFP fluorescence microscopy. Campanula medium regeneration and genetic transformation methods were established while various factors affecting the transformation efficiency were identified such as pre-culture treatment of leaf explants and different Agrobacterium strains.
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regeneration and transformation in adult plants of Campanula species
Plant Cell Reports, 2008Co-Authors: Sridevy Sriskandarajah, Heiko Mibus, Margrethe SerekAbstract:Adult plants are known for recalcitrance when it comes to adventitious organ formation and regeneration. Methods used for regeneration in explants from seedlings of Campanula carpatica failed to work for explants from adult plants of the same species. The present investigation generated efficient regeneration methods for mature specimens of four species of Campanula, C. carpatica, C. haylodgensis, C. portenschlagiana and C. poscharskyana. Petiole explants from dark-grown in vitro shoot cultures grown from nodal cuttings of adult plants regenerated successfully (95%), while explants from light-grown in vitro shoot cultures and greenhouse-grown plants regenerated at 12% and zero percentage, respectively. Dark-treatment, along with media manipulation with plant growth regulators, further enhanced regenerative capacity of the explants. A MS-based medium containing 10mg l −1 TDZ and 0.25 mg l−1 NAA was the most efficient regeneration medium. Transgenic shoots from C. carpatica (3%) and C. haylodgensis (1%) and transgenic callus from all species were produced using Agrobacterium tumefaciens, and transformation was confirmed by histochemical and Southern blot analyses. Protocols developed in this study may be useful for achieving efficient regeneration and transformation of recalcitrant adult plants.
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Transgenic Campanula carpatica plants with reduced ethylene sensitivity
Plant Cell Reports, 2007Co-Authors: Sridevy Sriskandarajah, Heiko Mibus, Margrethe SerekAbstract:Fertile transgenic Campanula carpatica Jacq. plants with flowers, which had reduced sensitivity to ethylene were obtained by Agrobacterium tumefaciens that mediated transformation. The construct used for transformation contained the etr1-1 gene from Arabidopsis thaliana under control of the flower specific fbp1 -promoter from petunia. More than 100 flowering T0 lines were tested for their ethylene sensitivity using 2 μl l^−1 ethylene. The tolerance level to ethylene varied among the lines. While control plants stopped flowering within 3 days of exposure to ethylene, one of the transformed lines flowered for up to 27 days. The presence and the expression pattern of the transgene in various tissues were studied by polymerase chain reaction (PCR) and reverse transcription (RT)-PCR techniques. The expression of etr1-1 was significant in flowers and buds. Transgenic lines did not differ morphologically from control plants. The selected transgenic T0 lines, which were re-established from in vitro cultures showed the same degree of tolerance to exogenous ethylene, confirming the stability of the transgene in in vitro cultures. The rooting ability of the transgenic plants was not affected by the presence of etr1-1 . T1 progeny were produced by crossing the transgenic line, which showed the most significant reduction in ethylene sensitivity with a control plant, and the analysis of the T1 plants showed 1:1 segregation in terms of ethylene sensitivity and the presence of the transgene.
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Induction of adventitious shoots in vitro in Campanula carpatica
Plant Cell Tissue and Organ Culture, 2001Co-Authors: Sridevy Sriskandarajah, Stefan Frello, Margrethe SerekAbstract:Efficient protocols have been developed to induce adventitious shoots in different types of explants of Campanula carpatica Jacq. More than five shoots per explant developed on hypocotyls of 5-week-old seedlings after 2 weeks of culture. Hypocotyls produced twice as many shoots as the cotyledons. TDZ proved to be about 6 times more efficient than BA. NAA had to be added to the regeneration medium to obtain the optimal balance of auxin and cytokinin to induce shoot regeneration. Significant differences were noted between different growth regulator concentrations in their effects on shoot organogenesis. BA induced double the number of callus clumps as TDZ. Incubation of explants in the dark produced about 6 shoots per explant while those in the light produced about 2 shoots per explant. Explants derived from 5-week-old seedlings were five times more regenerative compared to those derived from 15-week-old seedlings. Explants from cv. White Uniform were more organogenic than those from cv. Blue Clip. Root segments were also found to form shoots when treated with CPPU.
Paulo Miletpinheiro - One of the best experts on this subject based on the ideXlab platform.
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flower visitors of Campanula are oligoleges more sensitive to host specific floral scents than polyleges
Journal of Chemical Ecology, 2017Co-Authors: Katharina Brandt, Paulo Miletpinheiro, Manfred Ayasse, Stefan Dotterl, Wittko FranckeAbstract:The pollen diet provided by adult bees to their offspring varies immensely. While some species collect pollen on several plants irrespective of their phylogenetic relatedness (polyleges), others collect only on plants within a genus or family (oligoleges). Floral scents play a central role in bee-plant interactions. To locate flowers, polyleges are assumed to rely on compounds commonly found as floral scent constituents, whereas oligoleges rely on unusual compounds to recognize host flowers unambiguously. Campanula flowers are visited by both polylectic and oligolectic species, and their scent bouquets consist of common and unusual (e.g., spiroacetals) volatiles. In a comparative approach, we performed electroantennographic analyses to investigate the antennal responses of three polyleges and three oligoleges to three common volatiles and four spiroacetals. We hypothesized that: 1) oligoleges and polyleges should respond similarly to common flower volatiles, and 2) Campanula oligoleges should be more sensitive to spiroacetals than are polyleges. In corroboration, we found that antennal sensitivity to common volatiles was similar among bees irrespective of pollen diet, whereas oligoleges of Campanula were more sensitive to spiroacetals than polyleges. Newly emerged bees of the Campanula oligolege Chelostoma rapunculi rely on spiroacetals for recognizing host-flowers, and our results suggest that this might also be true for other Campanula oligoleges, since Chelostoma Campanularum and Hoplitis mitis also were able to perceive these specific volatiles at very low concentrations. Together, our results provide interesting insights into the significance of olfactory adaptations in oligolectic and polylectic bee species.
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visual and olfactory floral cues of Campanula Campanulaceae and their significance for host recognition by an oligolectic bee pollinator
PLOS ONE, 2015Co-Authors: Paulo Miletpinheiro, Manfred Ayasse, Stefan DotterlAbstract:Oligolectic bees collect pollen from a few plants within a genus or family to rear their offspring, and are known to rely on visual and olfactory floral cues to recognize host plants. However, studies investigating whether oligolectic bees recognize distinct host plants by using shared floral cues are scarce. In the present study, we investigated in a comparative approach the visual and olfactory floral cues of six Campanula species, of which only Campanula lactiflora has never been reported as a pollen source of the oligolectic bee Ch. rapunculi. We hypothesized that the flowers of Campanula species visited by Ch. rapunculi share visual (i.e. color) and/or olfactory cues (scents) that give them a host-specific signature. To test this hypothesis, floral color and scent were studied by spectrophotometric and chemical analyses, respectively. Additionally, we performed bioassays within a flight cage to test the innate color preference of Ch. rapunculi. Our results show that Campanula flowers reflect the light predominantly in the UV-blue/blue bee-color space and that Ch. rapunculi displays a strong innate preference for these two colors. Furthermore, we recorded spiroacetals in the floral scent of all Campanula species, but Ca. lactiflora. Spiroacetals, rarely found as floral scent constituents but quite common among Campanula species, were recently shown to play a key function for host-flower recognition by Ch. rapunculi. We conclude that Campanula species share some visual and olfactory floral cues, and that neurological adaptations (i.e. vision and olfaction) of Ch. rapunculi innately drive their foraging flights toward host flowers. The significance of our findings for the evolution of pollen diet breadth in bees is discussed.
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host location by visual and olfactory floral cues in an oligolectic bee innate and learned behavior
Behavioral Ecology, 2012Co-Authors: Clemens Schlindwein, Paulo Miletpinheiro, Manfred Ayasse, Heidi E M Dobson, Stefan DotterlAbstract:Oligolectic bees collect pollen from only a few related plant taxa, and our understanding of both the bees' innate and learned behavior in host-plant recognition is incomplete. For the oligolectic bee Chelostoma rapunculi, whose host plants are within Campanula, we conducted choice tests on foraging-naive individuals to investigate the bee's innate preference for visual and olfactory floral cues of its host plants over those of nonhost plants. In addition, we tested both foraging-naive and foraging-experienced individuals to determine the relative importance of these 2 sensory modalities in the bee's innate and learned host-flower location. Visual and olfactory cues of Campanula trachelium flowers, both separately and combined, attracted significantly more foraging-naive bees than equivalent cues of nonhost plants. Furthermore, for both foraging-naive and -experienced bees, the visual cues of host plants were more attractive than the olfactory ones, and the 2 cues combined attracted more bees than either alone. In foraging-naive bees, visual and olfactory cues alone elicited almost exclusively approaches, whereas after the bees gained foraging experience, landings became more frequent in response to visual cues but not to olfactory cues; in both bee groups, the combination of visual and olfactory cues was most effective in promoting landings. We conclude that Ch. rapunculi has an innate preference for the floral cues of its host plants over those of nonhost species and that both foraging-naive and foraging-experienced bees integrate visual and olfactory cues to find their host flowers, with a slightly greater reliance on visual cues in bees with foraging experience.
Juan José Aldasoro - One of the best experts on this subject based on the ideXlab platform.
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Phylogenetic and phylogeographic evidence for a Pleistocene disjunction between Campanula jacobaea (Cape Verde Islands) and C. balfourii (Socotra).
Molecular phylogenetics and evolution, 2013Co-Authors: Marisa Alarcón, Cristina Roquet, Alfredo García-fernández, Pablo Vargas, Juan José AldasoroAbstract:Abstract Our understanding of processes that led to biogeographic disjunct patterns of plant lineages in Macaronesia, North Africa and Socotra remains poor. Here, we study a group of Campanula species distributed across these areas integrating morphological and reproductive traits with phylogenetic and phylogeographic data based on the obtention of sequences for 4 highly variable cpDNA regions and AFLP data. The phylogeny obtained shows a sister relationship between Campanula jacobaea (endemic to Cape Verde Islands) and C. balfourii (endemic to Socotra), thus revealing a striking disjunct pattern (8300 km). These species diverged around 1.0 Mya; AFLP and haplotype data suggest that no genetic interchange has occurred since then. Their closest taxon, C. hypocrateriformis, is endemic to SW Morocco. The archipelagos of Macaronesia and Socotra have probably acted as refugia for North-African species, leading to speciation through isolation. Although C. balfourii has a restricted distribution, its genetic variability suggests that its populations have suffered no bottlenecks. C. jacobaea is also genetically rich and its distribution across Cape Verde Islands seems to have been influenced by the NE–SW trade winds, which may also have favoured the admixture found among the populations of the three southern islands. Floral features of the morphologically hypervariable C. jacobaea were also measured to assess whether the taxon C. bravensis, described for some of the southeast populations of C. jacobaea, corresponds to a different evolutionary entity. We show that morphological variation in C. jacobaea does not correspond to any genetic or geographic group.
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reconstructing the history of Campanulaceae with a bayesian approach to molecular dating and dispersal vicariance analyses
Molecular Phylogenetics and Evolution, 2009Co-Authors: Cristina Roquet, Llorenc Saez, Alfonso Susanna, Nuria Garciajacas, Isabel Sanmartin, Niklas Wikstrom, Juan José AldasoroAbstract:We reconstruct here the spatial and temporal evolution of the Campanula alliance in order to better understand its evolutionary history. To increase phylogenetic resolution among major groups (Wahlenbergieae–Campanuleae), new sequences from the rbcL region were added to the trnL-F dataset obtained in a previous study. These phylogenies were used to infer ancestral areas and divergence times in Campanula and related genera using a Bayesian approach to molecular dating and dispersal–vicariance analyses that takes into account phylogenetic uncertainty. The new phylogenetic analysis confirms Platycodoneae as the sister group of Wahlenbergieae–Campanuleae, the two last ones inter-graded into a well-supported clade. Biogeographic and dating analyses suggest that Western Asia and the Eastern Mediterranean have played a major role as centers of migration and diversification within the Campanula alliance, probably in relation to the intense orogenic activity that took place in this region during the Late Neogene, and that could have promoted isolation and allopatric speciation within lineages. Diversification rates within several Campanula lineages would have increased at the end of the Miocene, coinciding with the Messinian Stage. Strong selective pressures from climate changes and the expansion of mountainous regions during this period are suggested to explain the adaptation to drought, cold or disturbed environments observed in many Campanula species. Several independent long-distance dispersal events to North America are inferred within the Rapunculus clade, which seem to be related to high ploidy levels.
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natural delineation molecular phylogeny and floral evolution in Campanula
Systematic Botany, 2008Co-Authors: Cristina Roquet, Juan José Aldasoro, Llorenc Saez, Alfonso Susanna, Maria Luisa Alarcon, Nuria GarciajacasAbstract:Abstract The circumscription and infrageneric classification of Campanula is highly controversial. Independent and combined data from nuclear and chloroplast sequences (trnL-trnF, ITS) were analyzed with Bayesian and parsimony methods to elucidate the phylogenetic relationships of Campanula and allied genera, and explore the biological processes that occurred during the evolution of this genus. The main sections and subgenera of Campanula and related genera were sampled extensively. Chromosome numbers, corolla types, habit and capsule dehiscence were mapped on the trees to search for evolutionary patterns. The phylogenetic analyses revealed that Campanula, as currently circumscribed, is not monophyletic. This genus is divided into two main clades: a large core of Campanula species that includes related genera (Adenophora, Asyneuma, Azorina, Campanulastrum, Diosphaera, Edraianthus, Githopsis, Hanatnisaya, Heterocodon, Legousia, Michauxia, Petromarula, Physoplexis, Phyteuma, Trachelium, and Triodanis), and ...
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a taxonomic revision of Campanula l subgenus sicyocodon feer damboldt and subgenus megalocalyx damboldt Campanulaceae
Botanical Journal of the Linnean Society, 2003Co-Authors: Llorenc Saez, Juan José AldasoroAbstract:A taxonomic study of Campanula L. subgenera Megalocalyx Damboldt and Sicyocodon (Feer) Damboldt is presented here. Taxonomical, nomenclatural, morphological, chromosomal, geographic and ecological data are recorded for each taxon. Based on these data, one species is included in C. subgenus Sicyocodon and 12 in C. subgenus Megalocalyx. In addition, 11 lectotypifications of specific and infraspecific names are made, and a taxonomic key and descriptions of subgeneric and specific taxa are given. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 141, 215–241.
Hasan Yildirim - One of the best experts on this subject based on the ideXlab platform.
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Campanula alisan kilincii Campanulaceae a new species from eastern anatolia turkey
Turkish Journal of Botany, 2014Co-Authors: Hasan Yildirim, Serdar şenolAbstract:Campanula alisan-kilincii Yildirim & Şenol (Campanulaceae) is described and illustrated as a new species from Malatya Province in eastern Anatolia, Turkey. The new species belongs to the section Rupestres, based on morphological features. It is morphologically similar to Campanula quercetorum and C. strigillosa but clearly differs from them based on the morphological differences presented in the species description. In addition, the conservation status, the distribution map, and notes on the biogeography and ecology of the new species are given.
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Campanula mugeana sp nov Campanulaceae from western anatolia turkey
Nordic Journal of Botany, 2013Co-Authors: Hasan YildirimAbstract:Campanula mugeana Yildirim (Campanulaceae) is described as a new species. Diagnostic morphological characters, full descriptions and detailed illustrations of the new species are given. Micrographs of seeds and pollen were taken with scanning electron microscopy (SEM). Campanula mugeana is restricted to the province of Izmir in western Anatolia, Turkey. It belongs to the section Quinqueloculares, subgenus Campanula based on floral features. Although C. mugeana has no close relatives within sect. Quinqueloculares, it shows some morphological similarities with C. saxatilis and C. davisii.
Stefan Dotterl - One of the best experts on this subject based on the ideXlab platform.
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flower visitors of Campanula are oligoleges more sensitive to host specific floral scents than polyleges
Journal of Chemical Ecology, 2017Co-Authors: Katharina Brandt, Paulo Miletpinheiro, Manfred Ayasse, Stefan Dotterl, Wittko FranckeAbstract:The pollen diet provided by adult bees to their offspring varies immensely. While some species collect pollen on several plants irrespective of their phylogenetic relatedness (polyleges), others collect only on plants within a genus or family (oligoleges). Floral scents play a central role in bee-plant interactions. To locate flowers, polyleges are assumed to rely on compounds commonly found as floral scent constituents, whereas oligoleges rely on unusual compounds to recognize host flowers unambiguously. Campanula flowers are visited by both polylectic and oligolectic species, and their scent bouquets consist of common and unusual (e.g., spiroacetals) volatiles. In a comparative approach, we performed electroantennographic analyses to investigate the antennal responses of three polyleges and three oligoleges to three common volatiles and four spiroacetals. We hypothesized that: 1) oligoleges and polyleges should respond similarly to common flower volatiles, and 2) Campanula oligoleges should be more sensitive to spiroacetals than are polyleges. In corroboration, we found that antennal sensitivity to common volatiles was similar among bees irrespective of pollen diet, whereas oligoleges of Campanula were more sensitive to spiroacetals than polyleges. Newly emerged bees of the Campanula oligolege Chelostoma rapunculi rely on spiroacetals for recognizing host-flowers, and our results suggest that this might also be true for other Campanula oligoleges, since Chelostoma Campanularum and Hoplitis mitis also were able to perceive these specific volatiles at very low concentrations. Together, our results provide interesting insights into the significance of olfactory adaptations in oligolectic and polylectic bee species.
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visual and olfactory floral cues of Campanula Campanulaceae and their significance for host recognition by an oligolectic bee pollinator
PLOS ONE, 2015Co-Authors: Paulo Miletpinheiro, Manfred Ayasse, Stefan DotterlAbstract:Oligolectic bees collect pollen from a few plants within a genus or family to rear their offspring, and are known to rely on visual and olfactory floral cues to recognize host plants. However, studies investigating whether oligolectic bees recognize distinct host plants by using shared floral cues are scarce. In the present study, we investigated in a comparative approach the visual and olfactory floral cues of six Campanula species, of which only Campanula lactiflora has never been reported as a pollen source of the oligolectic bee Ch. rapunculi. We hypothesized that the flowers of Campanula species visited by Ch. rapunculi share visual (i.e. color) and/or olfactory cues (scents) that give them a host-specific signature. To test this hypothesis, floral color and scent were studied by spectrophotometric and chemical analyses, respectively. Additionally, we performed bioassays within a flight cage to test the innate color preference of Ch. rapunculi. Our results show that Campanula flowers reflect the light predominantly in the UV-blue/blue bee-color space and that Ch. rapunculi displays a strong innate preference for these two colors. Furthermore, we recorded spiroacetals in the floral scent of all Campanula species, but Ca. lactiflora. Spiroacetals, rarely found as floral scent constituents but quite common among Campanula species, were recently shown to play a key function for host-flower recognition by Ch. rapunculi. We conclude that Campanula species share some visual and olfactory floral cues, and that neurological adaptations (i.e. vision and olfaction) of Ch. rapunculi innately drive their foraging flights toward host flowers. The significance of our findings for the evolution of pollen diet breadth in bees is discussed.
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host location by visual and olfactory floral cues in an oligolectic bee innate and learned behavior
Behavioral Ecology, 2012Co-Authors: Clemens Schlindwein, Paulo Miletpinheiro, Manfred Ayasse, Heidi E M Dobson, Stefan DotterlAbstract:Oligolectic bees collect pollen from only a few related plant taxa, and our understanding of both the bees' innate and learned behavior in host-plant recognition is incomplete. For the oligolectic bee Chelostoma rapunculi, whose host plants are within Campanula, we conducted choice tests on foraging-naive individuals to investigate the bee's innate preference for visual and olfactory floral cues of its host plants over those of nonhost plants. In addition, we tested both foraging-naive and foraging-experienced individuals to determine the relative importance of these 2 sensory modalities in the bee's innate and learned host-flower location. Visual and olfactory cues of Campanula trachelium flowers, both separately and combined, attracted significantly more foraging-naive bees than equivalent cues of nonhost plants. Furthermore, for both foraging-naive and -experienced bees, the visual cues of host plants were more attractive than the olfactory ones, and the 2 cues combined attracted more bees than either alone. In foraging-naive bees, visual and olfactory cues alone elicited almost exclusively approaches, whereas after the bees gained foraging experience, landings became more frequent in response to visual cues but not to olfactory cues; in both bee groups, the combination of visual and olfactory cues was most effective in promoting landings. We conclude that Ch. rapunculi has an innate preference for the floral cues of its host plants over those of nonhost species and that both foraging-naive and foraging-experienced bees integrate visual and olfactory cues to find their host flowers, with a slightly greater reliance on visual cues in bees with foraging experience.