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Julien B Bachelier - One of the best experts on this subject based on the ideXlab platform.
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Osmophores and floral fragrance in Anacardium humile and Mangifera indica (Anacardiaceae): an overlooked secretory structure in Sapindales.
Aob Plants, 2018Co-Authors: Elisabeth Emilia Augusta Dantas Tölke, Julien B Bachelier, Elimar Alves De Lima, Marcelo J. P. Ferreira, Diego Demarco, Sandra Maria Carmello-guerreiroAbstract:: Flowers of Anacardiaceae and other Sapindales typically produce nectar, but scent, often associated with a reward for pollinators, has surprisingly been mentioned only rarely for members of the family and order. However, flowers of Anacardium humile and Mangifera indica produce a strong sweet scent. The origin and composition of these floral scents is the subject of this study. Screening of potential osmophores on the petals and investigations of their anatomy were carried out by light, scanning and transmission electron microscopy. The composition of the floral fragrance was characterized by gas chromatography-mass spectrometry. In both species, the base of the adaxial side of each petal revealed specialized secretory epidermal cells which are essentially similar in structure and distinct from all other neighbouring cells. These cells also showed evidence of granulocrine secretory mechanisms and slight specific variations in their subcellular apparatus coinciding with the respective composition of the floral fragrance, predominantly composed of sesquiterpenes in A. humile and monoterpenes in M. indica. This study reports the presence of osmophores for the first time in flowers of Anacardiaceae and confirms the link between the ultrastructural features of their secretory cells and the volatiles produced by the flowers. The flowers of most Sapindales, including Anacardiaceae, are nectariferous. However, the presence of osmophores has only been described for very few genera of Rutaceae and Sapindaceae. Both the occurrence of osmophores and fragrance may have largely been overlooked in Anacardiaceae and Sapindales until now. Further studies are needed to better understand the nature and diversity of the interactions of their nectariferous flowers with their pollinators.
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comparative floral morphology and anatomy of anacardiaceae and burseraceae Sapindales with a special focus on gynoecium structure and evolution
Botanical Journal of the Linnean Society, 2009Co-Authors: Julien B BachelierAbstract:Anacardiaceae and Burseraceae are traditionally distinguished by the number of ovules (1 vs. 2) per locule and the direction of ovule curvature (syntropous vs. antitropous). Recent molecular phylogenetic studies have shown that these families are sister groups in Sapindales after having been separated in different orders for a long time. We present a comparative morphological study of the flower structure in both families. The major clades, usually supported in molecular phylogenetic analyses, are well supported by floral structure. In Anacardiaceae, there is a tendency to gynoecium reduction to a single fertile carpel (particularly in Anacardioideae). The single ovule has a long and unusually differentiated funicle, which connects with the stylar pollen tube transmitting tract in all representatives studied. In Anacardiaceae–Spondiadoideae, there is a tendency to form an extensive synascidiate zone, with a massive remnant of the floral apex in the centre; these features are also present in Beiselia (Burseraceae) and Kirkiaceae (sister to Anacardiaceae plus Burseraceae) and may represent a synapomorphy or apomorphic tendency for the three families. In core Burseraceae, gynoecium structure is much less diverse than in Anacardiaceae and has probably retained more plesiomorphies. Differences in proportions of parts of the ovules in Anacardiaceae and Burseraceae are linked with the different direction of ovule curvature. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159, 499–571.
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comparative study of the floral morphology and anatomy in anacardiaceae burseraceae and kirkiaceae Sapindales
Bachelier Julien B. Comparative study of the floral morphology and anatomy in Anacardiaceae Burseraceae and Kirkiaceae (Sapindales). 2009 University o, 2009Co-Authors: Julien B BachelierAbstract:Amphipterygium was originally placed in its own family, Julianiaceae, mainly because of its unique infructescences, which form samaroid dispersal units containing a single fertile, one-seeded fruit and three or more sterile fruits enclosed in a cupulelike structure. Its position in Anacardiaceae-Anacardioideae and a close relationship with Pistacia were suggested by structural and chemical features, and the position of both genera in Anacardioideae was recently supported by molecular phylogenetic studies. However, the development and structure of these infructescences and flowers have never been analyzed and comparatively studied. This study shows that each samaroid structure in Amphipterygium is a few-flowered cyme and that the teeth at the entrance of the cupule are the subtending bracts of the flowers. A comparison of Amphipterygium with Pistacia also shows that both genera share with Rhus and other genera of Anacardioideae a tricarpellate, pseudomonomerous gynoecium with a unilocular ovary and a single crassinucellar and (hemi)anatropous ovule with a ponticulus. However, the ovules in both Amphipterygium and Pistacia are outstanding in being unitegmic (though sometimes with traces of a second integument on the convex side) and having a massive funicle with unique lateral and median outgrowths, which becomes much larger than the ovule after anthesis. The funicle is also proportionally much larger and more complicated in shape than that of all other Anacardiaceae studied. In addition, both genera are wind pollinated and thus exhibit similar evolutionary trends, such as dioecy, reduction of perianth (lack of petals and, at least in part, also of sepals), large (bilobed) stigmas with multicellular papillae, and similar pollen. It is not yet clear whether wind pollination evolved separately in each genus or only once in their common ancestor. However, the inclusion of Amphipterygium within Anacardioideae is strongly supported by floral reproductive structures.
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floral structure of kirkia kirkiaceae and its position in Sapindales
Annals of Botany, 2008Co-Authors: Julien B Bachelier, Peter K EndressAbstract:Background and Aims The monogeneric Kirkiaceae (Sapindales) were formerly placed as Kirkioideae in Simaroubaceae. However, recent molecular phylogenetic studies indicate that they are not in Simaroubaceae and they appear to be sister to the clade of Anacardiaceae plus Burseraceae. Such affinity was never considered or discussed since the first description of Kirkia. The present study is the first detailed analysis of the floral structure of a representative of Kirkiaceae and the first comparison with other sapindalean families, especially Anacardiaceae and Burseraceae.
Alexandra N. Muellner - One of the best experts on this subject based on the ideXlab platform.
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biogeography of cedrela meliaceae Sapindales in central and south america
American Journal of Botany, 2010Co-Authors: Alexandra N. Muellner, Terence D Pennington, Valerie A Koecke, Susanne S RennerAbstract:Dated phylogenies have helped clarify the complex history of many plant families that today are restricted to the world's tropical forests, but that have Eocene, Oligocene, and Miocene fossils from the northern hemisphere. One such family is the Meliaceae. Here we infer the history of the neotropical Meliaceae genus Cedrela (17 species), the sister clade of which today is restricted to tropical Asia. Sequences from the nuclear ribosomal spacer region and five plastid loci obtained for all ingroup species and relevant outgroups were used to infer species relationships and for molecular-clock dating under two Bayesian relaxed clock models. The clock models differed in their handling of rate autocorrelation and sets of fossil constraints. Results suggest that (1) crown group diversification in Cedrela started in the Oligocene/Early Miocene and intensified in the Late Miocene and Early Pliocene, and (2) Central American Cedrela species do not form a clade, implying reentry into Central America after the closure of the Panamanian Isthmus. At present, Cedrela is distributed in both dry and humid habitats, but morphological features suggest an origin in dry forest under seasonal climates, fitting with Miocene and Pliocene Cedrela fossils from deciduous forests.
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Genetic diversity and geographic structure in Aglaia elaeagnoidea (Meliaceae, Sapindales), a morphologically complex tree species, near the two extremes of its distribution
Blumea - Biodiversity Evolution and Biogeography of Plants, 2009Co-Authors: Alexandra N. Muellner, Harald Greger, Caroline M. PannellAbstract:Aglaia elaeagnoidea is the most widespread and one of the more morphologically diverse complex species in the largest genus of the mahogany family (Meliaceae, Sapindales). We performed maximum parsimony, maximum likelihood and Bayesian analyses (nuclear ITS rDNA) to estimate genetic relations among samples of Aglaia elaeagnoidea, and their phylogenetic position within Aglaia (more than 120 species in Indomalesia, Australasia, and the Pacific islands). Based on 90 accessions of Melioideae (ingroup) and four taxa of Cedreloideae (outgroup), this study 1) provides a first assessment of the genetic diversity of Aglaia elaeagnoidea; 2) investigates the geographic structure of the data in selected eastern and western regions of its distribution; and 3) suggests that Australia has been colonized only recently by A. elaeagnoidea and other species within the genus (Miocene/Pliocene boundary to Pliocene). Based on DNA data, morphology and additional evidence derived from biogenetic trends (secondary metabolites), the name Aglaia roxburghiana could be reinstated for specimens from the western end (India, Sri Lanka), but we have no data yet to indicate definitely where A. roxburghiana ends and A. elaeagnoidea begins either morphologically or geographically. Viewed in a more general context, Aglaieae are an ideal model group for obtaining more insights into the origin and evolution of Indomalesian and Australian biotas.
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the origin and evolution of indomalesian australasian and pacific island biotas insights from aglaieae meliaceae Sapindales
Journal of Biogeography, 2008Co-Authors: Alexandra N. Muellner, Caroline M. Pannell, Annette W Coleman, Mark W. ChaseAbstract:Aim The role of long-distance dispersal in the Indomalesian, Australasian and Pacific flora is currently hotly debated. The lack of well-resolved phylogenetic trees for Pacific plants has been a major limitation for biogeographical analysis. Here, we present a well-resolved phylogenetic tree for the tribe Aglaieae in the mahogany family, Meliaceae, and use it to investigate the origin, evolution and dispersal history of biotas in this area. The subfamily Melioideae, including the tribe Aglaieae (Meliaceae, Sapindales), is a plant group with good representation in the region in terms of biomass and species numbers, wide ecological attributes and known animal vectors. The family has a good fossil record (especially from North America and Europe). Genera and species in the tribe Aglaieae therefore provide an excellent model group for addressing this debate. Location Indomalesia, Australasia, Pacific islands. Methods Results from nuclear internal transcribed spacer ribosomal DNA analyses of 82 taxa, based on sequence alignment guided by secondary structure models, were combined with evidence from fossils and distribution data. We used strict and relaxed molecular clock approaches to estimate divergence times within Aglaieae. Putative ancestral areas were investigated through area-based and event-based biogeographical approaches. Information on dispersal routes and their direction was inferred from the investigation of dispersal asymmetries between areas. Results Our study indicates that the crown group of Aglaieae dates back at least to the Late Eocene, with major divergence events occurring during the Oligocene and Miocene. It also suggests that dispersal routes existed during Miocene–Pliocene times from the area including Peninsular Malaysia, Sumatra and Borneo to Wallacea, India and Indochina, and from the area including New Guinea, New Ireland and New Britain further east to the Pacific islands at the peripheries of the distribution range. The origin of the Fijian species dates back to the Pliocene. Main conclusions Dispersal over oceanic water barriers has occurred during geological time and seems to have been a major driving force for divergence events in Aglaieae, with some old Gondwanan land masses (e.g. Australia) colonized only during recent times. Movement from the ancestral area was predominantly towards the east. Extant Fijian species of Aglaia are monophyletic and share morphological features rarely found in species of other areas, suggesting speciation within an endemic clade. Divergence of living taxa from their closest living relatives took place during both the Miocene and the Pliocene, and peaked in the Pliocene. The present-day distribution of many species in the tribe must therefore have arisen as a result of dispersal rather than vicariance events. Furthermore, colonization from Indomalesia to Australasia and the Pacific has frequently been followed by speciation.
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placing biebersteiniaceae a herbaceous clade of Sapindales in a temporal and geographic context
Plant Systematics and Evolution, 2007Co-Authors: Alexandra N. Muellner, D D Vassiliades, Susanne S RennerAbstract:Biebersteiniaceae comprise a single genus with four species of perennial herbs occurring from central Asia to Greece. A previous molecular phylogenetic study placed one of the species in an isolated position in Sapindales, while morphological studies had placed Biebersteinia in or near Geraniaceae, albeit doubtfully. We tested the monophyly and placement of the family with data from the chloroplast genes rbcL and atpB obtained for all four species, other major clades of Sapindales and outgroups for a total of up to 114 taxa. Parsimony, Bayesian, and likelihood analyses place Biebersteinia in Sapindales, possibly as sister to the other eight families. Strict and relaxed molecular clocks constrained with fossils of Biebersteinia and up to eight other Sapindales suggest that the Biebersteinia crown group diversified in the Oligocene and Miocene, while the stem lineage dates back to the Late Paleocene. Ages for other sapindalean families are earlier than those obtained in more sparsely sampled analyses, although estimates for Burseraceae agree surprisingly well. Ancestral area analyses suggest that Biebersteinia expanded from the eastern part of its range (i.e. Tibet and Inner Mongolia) to the west, although analyses are hampered by the unclear sister group relationships.
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molecular phylogenetics of meliaceae Sapindales based on nuclear and plastid dna sequences
American Journal of Botany, 2003Co-Authors: Alexandra N. Muellner, Terence D Pennington, Rosabelle Samuel, Sheila A Johnson, Martin Cheek, Mark W. ChaseAbstract:Phylogenetic analyses of Meliaceae, including representatives of all four currently recognized subfamilies and all but two tribes (32 genera and 35 species, respectively), were carried out using DNA sequence data from three regions: plastid genes rbcL, matK (partial), and nuclear 26S rDNA (partial). Individual and combined phylogenetic analyses were performed for the rbcL, matK, and 26S rDNA data sets. Although the percentage of informative characters is highest in the segment of matK sequenced, rbcL provides the greatest number of informative characters of the three regions, resulting in the best resolved trees. Results of parsimony analyses support the recognition of only two subfamilies (Melioideae and Swietenioideae), which are sister groups. Melieae are the only tribe recognized previously that are strongly supported as monophyletic. The members of the two small monogeneric subfamilies, Quivisianthe and Capuronianthus, fall within Melioideae and Swietenioideae, respectively, supporting their taxonomic inclusion in these groups. Furthermore, the data indicate a close relationship between Aglaieae and Guareeae and a possible monophyletic origin of Cedreleae of Swietenioideae. For Trichilieae (Melioideae) and Swietenieae (Swietenioideae) lack of monophyly is indicated.
William A Overholt - One of the best experts on this subject based on the ideXlab platform.
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host range tests reveal paectes longiformis is not a suitable biological control agent for the invasive plant schinus terebinthifolia
Biocontrol, 2014Co-Authors: Veronica Manrique, Rodrigo Diaz, Todd Condon, William A OverholtAbstract:The most critical step during a weed biological control program is determination of a candidate agent’s host range. Despite rigorous protocols and extensive testing, there are still concerns over potential non-target effects following field releases. With the objective to improve risk assessment in biological control, no-choice and choice testing followed by a multiple generation study were conducted on the leaf-defoliator, Paectes longiformis Pogue (Lepidoptera: Euteliidae). This moth is being investigated as a biological control agent of Schinus terebinthifolia Raddi (Sapindales: Anacardiaceae), which is one of the worst invasive plant species in Florida, USA. Results from no-choice testing showed higher larval survival on S. terebinthifolia (48 %) and its close relative Schinus molle L. (47 %), whereas lower survival was obtained on six non-target species (<25 %). When given a choice, P. longiformis females preferred to lay eggs on the target weed, but oviposition also occurred on four non-target species. An improved performance on the native Rhus aromatica Aiton was found when insects were reared exclusively on this non-target species for one or two generations. Results from host range testing suggest that this moth is oligophagous, but has a preference for the target weed. Non-target effects found during multiple generation studies indicate that P. longiformis should not be considered as a biological control agent of S. terebinthifolia.
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comparison of two populations of pseudophilothrips ichini thysanoptera phlaeothripidae as candidates for biological control of the invasive weed schinus terebinthifolia Sapindales anacardiaceae
Biocontrol Science and Technology, 2014Co-Authors: Veronica Manrique, G S Wheeler, Rodrigo Diaz, Lenin Erazo, Neha Reddi, Dean A Williams, William A OverholtAbstract:Brazilian peppertree, Schinus terebinthifolia Raddi (Sapindales: Anacardiaceae) (hereafter Schinus), is one of the worst invasive species in Florida and Hawaii. The thrips Pseudophilothrips ichini Hood (Thysanoptera: Phlaeothripidae) is being considered as a potential biological control agent of Schinus. Two populations of this thrips were collected in the weed's native range; one from central-east Brazil (Ouro Preto thrips) and a second from north-east Brazil (Salvador thrips). Temperature requirements, adult fecundity and impact on different plant haplotypes by P. ichini were examined in the laboratory. Complete development of thrips from both populations occurred at temperatures ranging from 20 to 30°C. Two approaches were used to model the predicted distributions of the thrips populations in the USA: the physiological model (NAPPFAST) based on cold tolerance and the ecological niche model based on climatic variables (MaxEnt). The physiological model predicted that both populations of P. ichini may est...
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effect of herbivory on growth and biomass allocation of brazilian peppertree Sapindales anacardiaceae seedlings in the laboratory
Biocontrol Science and Technology, 2009Co-Authors: Veronica Manrique, James P Cuda, William A OverholtAbstract:Abstract Brazilian peppertree (Schinus terebinthifolius Raddi), native to South America, is invading many ecosystems in south and central Florida. The defoliating tortricid moth Episimus unguiculus Clarke was selected as a potential biocontrol agent of Brazilian peppertree in Florida. The objective of this study was to examine the effect of different levels of herbivore damage on growth and biomass allocation of Brazilian peppertree seedlings in the laboratory. Three treatments were established: (1) no herbivory (control), (2) low herbivory (~4 larvae/plant), and (3) high herbivory (~12 larvae/plant). High levels of herbivory significantly reduced the number of leaflets, plant height, foliar biomass, foliar relative growth rate (RGR) and shoot: root ratio of Brazilian peppertree seedlings. Moreover, plants were not able to recover from herbivory after 2 months. The performance of Brazilian peppertree subjected to low herbivory levels did not differ from the control plants (no herbivory). The potential eff...
Susanne S Renner - One of the best experts on this subject based on the ideXlab platform.
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biogeography of cedrela meliaceae Sapindales in central and south america
American Journal of Botany, 2010Co-Authors: Alexandra N. Muellner, Terence D Pennington, Valerie A Koecke, Susanne S RennerAbstract:Dated phylogenies have helped clarify the complex history of many plant families that today are restricted to the world's tropical forests, but that have Eocene, Oligocene, and Miocene fossils from the northern hemisphere. One such family is the Meliaceae. Here we infer the history of the neotropical Meliaceae genus Cedrela (17 species), the sister clade of which today is restricted to tropical Asia. Sequences from the nuclear ribosomal spacer region and five plastid loci obtained for all ingroup species and relevant outgroups were used to infer species relationships and for molecular-clock dating under two Bayesian relaxed clock models. The clock models differed in their handling of rate autocorrelation and sets of fossil constraints. Results suggest that (1) crown group diversification in Cedrela started in the Oligocene/Early Miocene and intensified in the Late Miocene and Early Pliocene, and (2) Central American Cedrela species do not form a clade, implying reentry into Central America after the closure of the Panamanian Isthmus. At present, Cedrela is distributed in both dry and humid habitats, but morphological features suggest an origin in dry forest under seasonal climates, fitting with Miocene and Pliocene Cedrela fossils from deciduous forests.
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placing biebersteiniaceae a herbaceous clade of Sapindales in a temporal and geographic context
Plant Systematics and Evolution, 2007Co-Authors: Alexandra N. Muellner, D D Vassiliades, Susanne S RennerAbstract:Biebersteiniaceae comprise a single genus with four species of perennial herbs occurring from central Asia to Greece. A previous molecular phylogenetic study placed one of the species in an isolated position in Sapindales, while morphological studies had placed Biebersteinia in or near Geraniaceae, albeit doubtfully. We tested the monophyly and placement of the family with data from the chloroplast genes rbcL and atpB obtained for all four species, other major clades of Sapindales and outgroups for a total of up to 114 taxa. Parsimony, Bayesian, and likelihood analyses place Biebersteinia in Sapindales, possibly as sister to the other eight families. Strict and relaxed molecular clocks constrained with fossils of Biebersteinia and up to eight other Sapindales suggest that the Biebersteinia crown group diversified in the Oligocene and Miocene, while the stem lineage dates back to the Late Paleocene. Ages for other sapindalean families are earlier than those obtained in more sparsely sampled analyses, although estimates for Burseraceae agree surprisingly well. Ancestral area analyses suggest that Biebersteinia expanded from the eastern part of its range (i.e. Tibet and Inner Mongolia) to the west, although analyses are hampered by the unclear sister group relationships.
Sandra Maria Carmello-guerreiro - One of the best experts on this subject based on the ideXlab platform.
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Osmophores and floral fragrance in Anacardium humile and Mangifera indica (Anacardiaceae): an overlooked secretory structure in Sapindales.
Aob Plants, 2018Co-Authors: Elisabeth Emilia Augusta Dantas Tölke, Julien B Bachelier, Elimar Alves De Lima, Marcelo J. P. Ferreira, Diego Demarco, Sandra Maria Carmello-guerreiroAbstract:: Flowers of Anacardiaceae and other Sapindales typically produce nectar, but scent, often associated with a reward for pollinators, has surprisingly been mentioned only rarely for members of the family and order. However, flowers of Anacardium humile and Mangifera indica produce a strong sweet scent. The origin and composition of these floral scents is the subject of this study. Screening of potential osmophores on the petals and investigations of their anatomy were carried out by light, scanning and transmission electron microscopy. The composition of the floral fragrance was characterized by gas chromatography-mass spectrometry. In both species, the base of the adaxial side of each petal revealed specialized secretory epidermal cells which are essentially similar in structure and distinct from all other neighbouring cells. These cells also showed evidence of granulocrine secretory mechanisms and slight specific variations in their subcellular apparatus coinciding with the respective composition of the floral fragrance, predominantly composed of sesquiterpenes in A. humile and monoterpenes in M. indica. This study reports the presence of osmophores for the first time in flowers of Anacardiaceae and confirms the link between the ultrastructural features of their secretory cells and the volatiles produced by the flowers. The flowers of most Sapindales, including Anacardiaceae, are nectariferous. However, the presence of osmophores has only been described for very few genera of Rutaceae and Sapindaceae. Both the occurrence of osmophores and fragrance may have largely been overlooked in Anacardiaceae and Sapindales until now. Further studies are needed to better understand the nature and diversity of the interactions of their nectariferous flowers with their pollinators.
