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Ana D Caperta - One of the best experts on this subject based on the ideXlab platform.
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ORIGINAL ARTICLE Male fertility versus sterility, cytotype, and DNA quantitative
2016Co-Authors: Ana Sofia, Róis Generosa Teixeira, Timothy F. Sharbel, Ana D CapertaAbstract:variation in seed production in diploid and tetraploid sea lavenders (Limonium sp., Plumbaginaceae) reveal diversity in reproduction mode
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Phylogeography and modes of reproduction in diploid and tetraploid halophytes of Limonium species (Plumbaginaceae): evidence for a pattern of geographical parthenogenesis
Annals of botany, 2015Co-Authors: Ana Sofia Rois, Timothy F. Sharbel, Flávio Sádio, Octávio S. Paulo, Generosa Teixeira, Ana Paula Paes, Dalila Espírito-santo, Ana D CapertaAbstract:Background and aims The genus Limonium (Plumbaginaceae) has long been recognized to have sexual and apomictic (asexual seed formation) modes of reproduction. This study aimed to elucidate phylogeographical patterns and modes of reproduction in diploid and tetraploid Limonium species, namely three putative sexual diploid species with morphological affinities (L. nydeggeri, L. ovalifolium, L. lanceolatum) and three related, probably apomict tetraploid species (L. binervosum, L. dodartii, L. multiflorum). Methods cpDNA diversity and differentiation between natural populations of the species were investigated using two chloroplast sequence regions (trnL intron and trnL-trnF intergenic spacer). Floral heteromorphies, ovule cytoembryological analyses and pollination and crossing tests were performed in representative species of each ploidy group, namely diploid L. ovalifolium and tetraploid L. multiflorum, using plants from greenhouse collections. Key results and conclusions Genetic analyses showed that diploid species have a higher haplotype diversity and a higher number of unique (endemic) haplotypes than tetraploid species. Network analysis revealed correlations between cpDNA haplotype distribution and ploidy groups, species groups and geographical origin, and haplotype sharing within and among species with distinct ploidy levels. Reproductive biology analyses showed that diploid L. ovalifolium mainly forms meiotically reduced tetrasporic embryo sacs of Gagea ova, Adoxa and Drusa types. Limonium multiflorum, however, has only unreduced, diplosporic (apomictic) embryo sacs of Rudbeckia type, and autonomous apomictic development seems to occur. Taken together, the findings provide evidence of a pattern of 'geographical parthenogenesis' in which quaternary climatic oscillations appear to be involved in the geographical patterns of coastal diploid and tetraploid Limonium species.
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male fertility versus sterility cytotype and dna quantitative variation in seed production in diploid and tetraploid sea lavenders Limonium sp plumbaginaceae reveal diversity in reproduction modes
Sexual Plant Reproduction, 2012Co-Authors: Ana Sofia Rois, Timothy F. Sharbel, G Teixeira, Jorg Fuchs, Sergio Martins, Dalila Espiritosanto, Ana D CapertaAbstract:The genus Limonium Miller, a complex taxonomic group, comprises annuals and perennials that can produce sexual and/or asexual seeds (apomixis). In this study, we used diverse cytogenetic and cytometric approaches to analyze male sporogenesis and gametogenesis for characterizing male reproductive output on seed production in Limonium ovalifolium and Limonium multiflorum. We showed here that the first species is mostly composed of diploid cytotypes with 2n = 16 chromosomes and the latter species by tetraploid cytotypes with 2n = 32, 34, 35, 36 chromosomes and had a genome roughly twice as big as the former one. In both species, euploid and aneuploid cytotypes with large metacentric chromosomes having decondensed interstitial sites were found within and among populations, possibly involved in chromosomal reconstructions. L. ovalifolium diploids showed regular meiosis resulting in normal tetrads, while diverse chromosome pairing and segregation irregularities leading to the formation of abnormal meiotic products are found in balanced and non-balanced L. multiflorum tetraploids. Before anther dehiscence, the characteristic unicellular, bicellular, or tricellular pollen grains showing the typical Limonium micro- or macro-reticulate exine ornamentation patterns were observed in L. ovalifolium using scanning electron microscopy. Most of these grains were viable and able to produce pollen tubes in vitro. In both balanced and unbalanced L. multiflorum tetraploids, microspores only developed until the “ring-vacuolate stage” with a collapsed morphology without the typical exine patterns, pointing to a sporophytic defect. These microspores were unviable and therefore never germinated in vitro. L. ovalifolium individuals presented larger pollen grains than those of L. multiflorum, indicating that pollen size and ploidy levels are not correlated in the Limonium system. Cytohistological studies in mature seeds from both species revealed that an embryo and a residual endosperm were present in each seed. Flow cytometric seed screens using such mature seeds showed quantitative variations in seeds ploidy level. It is concluded that male function seems to play an important role in the reproduction modes of Limonium diploids and tetraploids.
Mark W. Chase - One of the best experts on this subject based on the ideXlab platform.
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phylogenetics of the irano turanian taxa of Limonium plumbaginaceae based on its nrdna sequences and leaf anatomy provides evidence for species delimitation and relationships of lineages
Botanical Journal of the Linnean Society, 2013Co-Authors: Hossein Akhani, Maryam Malekmohammadi, Parastoo Mahdavi, Arootin Gharibiyan, Mark W. ChaseAbstract:In a taxonomic and molecular phylogenetic study using nuclear ribosomal internal transcribed spacer (ITS) DNA sequences and anatomical data, the taxonomic status and relationships of Irano-Turanian Limonium spp. were investigated. The results of molecular phylogenetic analysis and anatomical synapomorphies showed that the Iranian Limonium spp. can be grouped into four major clades: (1) an unresolved clade including species of section Pteroclados as sister to all other Limonium spp.; (2) the L. axillare clade as sister to all Irano-Turanian and Mediterranean species; (3) a poorly supported clade consisting of species of section Nephrophyllum, L. caspium, L. bellidifolium and L. iconium of section Limonium subsection Hyalolepidae and the isolated species L. sogdianum (section Siphonocalyx) and L. nudum (section Platyhymenium); and (4) a well-supported clade including species of section Limonium subsection Limonium, part of section Sarcophyllum and L. lilacinum of section Sphaerostachys. The most diverse Mediterranean clade with many microspecies and apomictic taxa has no representatives in the Irano-Turanian area. The ITS results agree with distribution and some morphological and anatomical characters, giving strong support for separating L. perfoliatum and L. reniforme that have been considered conspecific in all recent taxonomic treatments. An updated key to all known Iranian Limonium spp., a synopsis of all species, with distribution maps, and descriptions and illustrations of Iranian species of section Nephrophyllum are provided. © 2013 The Linnean Society of London
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Molecular phylogenetics of Limonium and related genera (Plumbaginaceae): biogeographical and systematic implications
American journal of botany, 2005Co-Authors: M. Dolores Lledó, Manuel B. Crespo, Michael F. Fay, Mark W. ChaseAbstract:Phylogenetic relationships within Limonium (Plumbaginaceae) are evaluated using sequence data from three plastid regions (rbcL, the trnL intron, and the trnL-trnF intergenic spacer). Sixty-six species representing the major genera of Staticoideae, including representatives of all sections and genera formerly included in Limonium, have been analyzed using four species of Plumbaginoideae as an outgroup. Analyses of each separate and combined data set yield similar results. Afrolimon is embedded in Limonium and related to L. vulgare, the type of Limonium. Limonium is split into two major clades corresponding to subgenera, but otherwise the current infrageneric classification proved to be artificial. Some groups restricted to particular areas can be recognized, and their synapomorphies are discussed. The presence of an isolated taxon in the Canary Islands is used as a calibration point for age estimates of the major events in the genus, including migrations to the Southern Hemisphere, the Canary Islands, and Asia. The rapid radiation of Limonium in the Mediterranean basin appears to coincide with the desiccation of the Mediterranean Sea in the Messinian (late Miocene).
T. Schiva - One of the best experts on this subject based on the ideXlab platform.
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Use of RAPD Markers for the Genetic Characterization of Limonium Species
2004Co-Authors: S. Bruna, A. Mercuri, T. Schiva, L. De Benedetti, G. Burchi, Nicola Pecchioni, C. AgrimontiAbstract:The genus Limonium (fam. Plumbaginaceae) consists of about 300 species of mostly herbaceous perennials, some low shrubs, and annuals. Most botanical species are endemics in the Mediterranean region, but many species have their centre of origin in Caucaso, Turkestan, Caspian Sea, Russia, Iran, China, and South Africa. Limonium is grown in several regions of the world for use as a cut flower for both fresh and dry-flower arrangements.In this work, RAPD analyses were used for the study of genetic relationships in Limonium. Thirteen wild species were tested with 10 primers. A total of 244 bands were scored and used for the analysis of genetic distances. The dendrogram obtained from cluster analysis showed high similarity among three species that some authors report as synonymous and that appeared very similar from our previous phenotypic observations (L. caspia, L. bellidifolium and L. otolepis). In order to clarify the genetic relationships, further analyses were carried out on several genotypes belonging to these species. The new dendrogram, obtained scoring 151 RAPD bands, showed that the genotypes did not group in clear clusters. Analysis of molecular variance (AMOVA) confirmed this trend: the highest genetic variation resulted among genotypes and only 6,58 % of the total variation resulted among the species. These results suggest that the species can be considered synonymous. The use of RAPD markers in our case was thus useful for clarifying the highly probable identity of the three Limonium species, in a plant genus that is notably of difficult interpretation.
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Modification of plant architecture in Limonium spp. induced by rol genes
Plant Cell Tissue and Organ Culture, 2001Co-Authors: A. Mercuri, S. Bruna, Laura De Benedetti, Gianluca Burchi, T. SchivaAbstract:An Agrobacterium-mediated transformation system for Limonium has been developed. The leaf explants of the sterile hybrid L116 (Limonium otolepis, Kuntze × Limonium latifolium, Kuntze) were inoculated with A. tumefaciens LBA4404 harboring the binary vector pBin19 containing a T-DNA fragment encompassing rol A,B and C genes of A. rhizogenes Ri plasmid (pRi1855). Transgenic shoots, regenerated on selection medium, were micropropagated, rooted, and transferred to soil. Southern analysis confirmed the insertion of rol genes into the plant genome. Three transgenic clones were selected and based on their phenotypic characteristics were named super-compact, compact and semi-compact types. In general the transformed plants showed ornamental traits such as dwarfness and early flowering which are highly desirable.
Andrew D. Hanson - One of the best experts on this subject based on the ideXlab platform.
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Choline-O-Sulfate Biosynthesis in Plants (Identification and Partial Characterization of a Salinity-Inducible Choline Sulfotransferase from Species of Limonium (Plumbaginaceae).
Plant physiology, 1994Co-Authors: Jean Rivoal, Andrew D. HansonAbstract:Choline-O-sulfate is a compatible osmolyte accumulated under saline conditions by members of the halophytic genus Limonium and other Plumbaginaceae. A choline sulfotransferase (EC 2.8.2.6) responsible for the formation of choline-O-sulfate was characterized in Limonium species. A simple radiometric assay was developed in which [14C]choline was used as substrate, and the h [14C]choline-O-sulfate product was isolated by ion-exchange chromatography. The choline sulfotransferase activity was soluble, required 3[prime]-phosphoadenosine-5[prime]-phosphosulfate as the sulfate donor, and showed a pH optimum at 9.0. Apparent Km values were 25 [mu]M for choline and 5.5 [mu]M for 3[prime]-phosphoadenosine-5[prime]-phosphosulfate. Choline sulfotransferase activity was detected in various Limonium species but was very low or absent from species that do not accumulate choline-O-sulfate. In roots and leaves of Limonium perezii, the activity was increased at least 4-fold by salinization with 40% (v/v) artificial sea water. Choline sulfotransferase activity was also induced in cell cultures of L. perezii following salt shock with 20% (v/v) artificial sea water or osmotic shock with 19% (w/v) polyethylene glycol 6000. Labeling experiments with [14C]choline confirmed that the enzyme induced in cell cultures was active in vivo.
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Identification and Partial Characterization of a Salinity-Inducible Choline Sulfotransferase from Species of Limonium (Plumbaginaceae)
1994Co-Authors: Jean Rivoal, Andrew D. HansonAbstract:Choline-O-sulfate is a compatible osmolyte accumulated under saline conditions by members of the halophytic genus Limonium and other Plumbaginaceae. A choline sulfotransferase (EC 2.8.2.6) responsible for the formation of choline-O-sulfate was characterized in Limonium species. A simple radiometric assay was developed in which [‘4C]choline was used as substrate, and the h [“Clcholine-O-sulfate product was isolated by ion-exchange chromatography. The choline sulfotransferase activity was soluble, required 3’-phosphoadenosine-5‘-phosphosulfate as the sulfate donor, and showed a pH optimum at 9.0. Apparent K,,, values were 25 p~ for choline and 5.5 p~ for 3‘-phosphoadenosine-5‘-phosphosulfate. Choline sulfotransferase activity was detected in various Limonium species but was very low or absent from species that do not accumulate choline-O-sulfate. In roots and leaves of Limonium perezii, the activity was increased at least 4-fold by salinization with 40% (v/v) artificial sea water. Choline sulfotransferase activity was also induced in cell cultures of 1. perezii following salt shock with 20% (v/v) artificial sea water or osmotic shock with 19% (w/v) polyethylene glycol 6000. Labeling experiments with [‘4C]choline confirmed that the enzyme induced in cell cultures was active in vivo.
Ana Sofia Rois - One of the best experts on this subject based on the ideXlab platform.
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Phylogeography and modes of reproduction in diploid and tetraploid halophytes of Limonium species (Plumbaginaceae): evidence for a pattern of geographical parthenogenesis
Annals of botany, 2015Co-Authors: Ana Sofia Rois, Timothy F. Sharbel, Flávio Sádio, Octávio S. Paulo, Generosa Teixeira, Ana Paula Paes, Dalila Espírito-santo, Ana D CapertaAbstract:Background and aims The genus Limonium (Plumbaginaceae) has long been recognized to have sexual and apomictic (asexual seed formation) modes of reproduction. This study aimed to elucidate phylogeographical patterns and modes of reproduction in diploid and tetraploid Limonium species, namely three putative sexual diploid species with morphological affinities (L. nydeggeri, L. ovalifolium, L. lanceolatum) and three related, probably apomict tetraploid species (L. binervosum, L. dodartii, L. multiflorum). Methods cpDNA diversity and differentiation between natural populations of the species were investigated using two chloroplast sequence regions (trnL intron and trnL-trnF intergenic spacer). Floral heteromorphies, ovule cytoembryological analyses and pollination and crossing tests were performed in representative species of each ploidy group, namely diploid L. ovalifolium and tetraploid L. multiflorum, using plants from greenhouse collections. Key results and conclusions Genetic analyses showed that diploid species have a higher haplotype diversity and a higher number of unique (endemic) haplotypes than tetraploid species. Network analysis revealed correlations between cpDNA haplotype distribution and ploidy groups, species groups and geographical origin, and haplotype sharing within and among species with distinct ploidy levels. Reproductive biology analyses showed that diploid L. ovalifolium mainly forms meiotically reduced tetrasporic embryo sacs of Gagea ova, Adoxa and Drusa types. Limonium multiflorum, however, has only unreduced, diplosporic (apomictic) embryo sacs of Rudbeckia type, and autonomous apomictic development seems to occur. Taken together, the findings provide evidence of a pattern of 'geographical parthenogenesis' in which quaternary climatic oscillations appear to be involved in the geographical patterns of coastal diploid and tetraploid Limonium species.
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male fertility versus sterility cytotype and dna quantitative variation in seed production in diploid and tetraploid sea lavenders Limonium sp plumbaginaceae reveal diversity in reproduction modes
Sexual Plant Reproduction, 2012Co-Authors: Ana Sofia Rois, Timothy F. Sharbel, G Teixeira, Jorg Fuchs, Sergio Martins, Dalila Espiritosanto, Ana D CapertaAbstract:The genus Limonium Miller, a complex taxonomic group, comprises annuals and perennials that can produce sexual and/or asexual seeds (apomixis). In this study, we used diverse cytogenetic and cytometric approaches to analyze male sporogenesis and gametogenesis for characterizing male reproductive output on seed production in Limonium ovalifolium and Limonium multiflorum. We showed here that the first species is mostly composed of diploid cytotypes with 2n = 16 chromosomes and the latter species by tetraploid cytotypes with 2n = 32, 34, 35, 36 chromosomes and had a genome roughly twice as big as the former one. In both species, euploid and aneuploid cytotypes with large metacentric chromosomes having decondensed interstitial sites were found within and among populations, possibly involved in chromosomal reconstructions. L. ovalifolium diploids showed regular meiosis resulting in normal tetrads, while diverse chromosome pairing and segregation irregularities leading to the formation of abnormal meiotic products are found in balanced and non-balanced L. multiflorum tetraploids. Before anther dehiscence, the characteristic unicellular, bicellular, or tricellular pollen grains showing the typical Limonium micro- or macro-reticulate exine ornamentation patterns were observed in L. ovalifolium using scanning electron microscopy. Most of these grains were viable and able to produce pollen tubes in vitro. In both balanced and unbalanced L. multiflorum tetraploids, microspores only developed until the “ring-vacuolate stage” with a collapsed morphology without the typical exine patterns, pointing to a sporophytic defect. These microspores were unviable and therefore never germinated in vitro. L. ovalifolium individuals presented larger pollen grains than those of L. multiflorum, indicating that pollen size and ploidy levels are not correlated in the Limonium system. Cytohistological studies in mature seeds from both species revealed that an embryo and a residual endosperm were present in each seed. Flow cytometric seed screens using such mature seeds showed quantitative variations in seeds ploidy level. It is concluded that male function seems to play an important role in the reproduction modes of Limonium diploids and tetraploids.
