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Marcel Rejmanek - One of the best experts on this subject based on the ideXlab platform.
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small genomes and large seeds chromosome numbers genome size and seed mass in diploid Aesculus species sapindaceae
Annals of Botany, 2017Co-Authors: Anna Krahulcova, Pavel Travnicek, Frantisek Krahulec, Marcel RejmanekAbstract:Background and Aims: Aesculus L. (horse chestnut, buckeye) is a genus of 12-19 extant woody species native to the temperate Northern Hemisphere. This genus is known for unusually large seeds among angiosperms. While chromosome counts are available for many Aesculus species, only one has had its genome size measured. The aim of this study is to provide more genome size data and analyse the relationship between genome size and seed mass in this genus. Methods: Chromosome numbers in root tip cuttings were confirmed for four species and reported for the first time for three additional species. Flow cytometric measurements of 2C nuclear DNA values were conducted on eight species, and mean seed mass values were estimated for the same taxa. Key Results: The same chromosome number, 2 n = 40, was determined in all investigated taxa. Original measurements of 2C values for seven Aesculus species (eight taxa), added to just one reliable datum for A. hippocastanum , confirmed the notion that the genome size in this genus with relatively large seeds is surprisingly low, ranging from 0·955 pg 2C -1 in A. parviflora to 1·275 pg 2C -1 in A. glabra var. glabra. Conclusions: The chromosome number of 2 n = 40 seems to be conclusively the universal 2 n number for non-hybrid species in this genus. Aesculus genome sizes are relatively small, not only within its own family, Sapindaceae, but also within woody angiosperms. The genome sizes seem to be distinct and non-overlapping among the four major Aesculus clades. These results provide an extra support for the most recent reconstruction of Aesculus phylogeny. The correlation between the 2C values and seed masses in examined Aesculus species is slightly negative and not significant. However, when the four major clades are treated separately, there is consistent positive association between larger genome size and larger seed mass within individual lineages.
Aj Harris - One of the best experts on this subject based on the ideXlab platform.
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The complete chloroplast genome of vulnerable Aesculus wangii ( Sapindaceae ), a narrowly endemic tree in Yunnan, China
Conservation Genetics Resources, 2017Co-Authors: Wei Zheng, Wei Wang, Aj HarrisAbstract:In this study, we assembled the complete chloroplast (cp) genome of Aesculus wangii Hu (Sapindaceae), a rare and vulnerable deciduous tree native to Southeast Yunnan of China. The cp genome of A. wangii was 155,871 bp in length and contained a pair of inverted repeat (IR, 26,390 bp) regions, which were separated by the small single copy (SSC, 18,209 bp) and the large single copy (LSC, 84,882 bp) regions. The cp genome encoded 135 genes including 84 protein-coding genes, 40 tRNA genes, and eight rRNA ribosomal genes. The overall AT content of A. wangii cp genome is 62.0%. The maximum likelihood phylogenetic analysis revealed that A. wangii is sister to maples of tribe Acereae and the Acereae-Aesculus clade is sister to all other sampled Sapindaceae. The cp genome of A. wangii will be useful for future studies on the conservation, taxonomy, and phylogeny of the genus Aesculus.
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Testing the monophyly of Aesculus L. and Billia Peyr., woody genera of tribe Hippocastaneae of the Sapindaceae
Molecular Phylogenetics and Evolution, 2016Co-Authors: Aj Harris, Qiu-yun Jenny Xiang, Larinda Holland, Jun WenAbstract:Hippocastaneae is a well-supported clade in Sapindaceae that comprises 15+ species; 12+ in Aesculus, two in Billia, and one in Handeliodendron Rehder. The monophyly of Aesculus and Billia were widely assumed, but a recent molecular phylogenetic study of Sapindanceae used seven species of Aesculus and one each of Billia and Handeliodendron and showed that Billia and Handeliodendron were nested within Aesculus. Here, we tested the hypothesis that Aesculus and Billia are mutually monophyletic using phylogenetic analyses of seven molecular markers and 31 accessions of Hippocastaneae representing 14 species. We performed phylogenetic analyses using a dataset of concatenated genes as well as with coalescent method for constructing a species tree from individual gene trees. The analysis of seven concatenated markers and the species tree strongly supported the mutual monophyly of Aesculus and Billia. We also recovered support for the traditional arrangement of genera within Hippocastaneae: Aesculus and Billia comprising a clade that is sister to Handeliodendron. However, the relationships among the genera remain incompletely resolved.
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Estimating paleoenvironments using ecological niche models of nearest living relatives: A case study of Eocene Aesculus L.
Journal of Systematics and Evolution, 2013Co-Authors: Aj Harris, Monica Papeş, Yun-dong Gao, Linda E. WatsonAbstract:Past climates experienced by fossil plant species have often been inferred based on the environmental requirements of their evolutionarily nearest living relatives (NLR). Here we have combined paleoclimatic estimation using NLRs with ecolological niche modeling (ENM) and have demonstrated the combined approach by inferring the Eocene environment of Aesculus L. (Hippocastanoideae, Sapindaceae), a genus of woody eudicots with extant species generally preferring temperate climates. Specifically, we applied ENM-NLR to four Eocene floras in which Aesculus fossils are known to occur: McAbee and Princeton (British Columbia), Republic (Washington State), and Spitsbergen (European Arctic Circle). Additionally, we used ENM-NLR to estimate whether paleoenvironmental conditions were suitable for Aesculus at a fifth flora, Copper Basin (Nevada), where the fossil record of the genus is less clear. We generated models for all NLRs in Genetic Algorithm for Rule Set Production using georeferenced data from the Global Biodiversity Information Facility and Bioclim environmental parameters. For each fossil flora, the best models of individual NLRs were summarized into composite community models, which were taken to represent climatically analogous modern communities and used to infer the paleoclimates of the fossil localities. Our results are generally consistent with previous studies that used other methods to estimate paleoclimates and suggest that McAbee, Princeton, Republic, and Spitsbergen had temperate environments. For the Copper Basin flora, our results show ranges of environmental variables that may be too broad for predicting whether Aesculus was present. Our study appears to be the first to combine the NLR approach and ENM to infer paleoclimates.
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estimating ancestral distributions of lineages with uncertain sister groups a statistical approach to dispersal vicariance analysis and a case using Aesculus l sapindaceae including fossils
Journal of Systematics and Evolution, 2009Co-Authors: Aj Harris, Qiu-yun Jenny XiangAbstract:We propose a simple statistical approach for using Dispersal-Vicariance Analysis (DIVA) software to infer biogeographic histories without fully bifurcating trees. In this approach, ancestral ranges are first optimized for a sample of Bayesian trees. The probability P of an ancestral range r at a node is then calculated as P(rY) = n t=1 F(rY)tPt where Y is a node, and F(rY) is the frequency of range r among all the optimal solutions resulting from DIVA optimization at node Y, t is one of n topologies optimized, and Pt is the probability of topology t. Node Y is a hypothesized ancestor shared by a specific crown lineage and the sister of that lineage "x", where x may vary due to phylogenetic uncertainty (polytomies and nodes with posterior probability <100%). Using this method, the ancestral distribution at Y can be estimated to provide inference of the geographic origins of the specific crown group of interest. This approach takes into account phylogenetic uncertainty as well as uncertainty from DIVA optimization. It is an extension of the previously described method called Bayes-DIVA, which pairs Bayesian phylogenetic analysis with biogeographic analysis using DIVA. Further, we show that the probability P of an ancestral range at Y calculated using this method does not equate to pp ∗ F(rY) on the Bayesian consensus tree when both variables are <100%, where pp is the posterior probability and F(rY) is the frequency of range r for the node containing the specific crown group. We tested our DIVA-Bayes approach using Aesculus L., which has major lineages unresolved as a polytomy. We inferred the most probable geographic origins of the five traditional sections of Aesculus and of Aesculus californica Nutt. and examined range subdivisions at parental nodes of these lineages. Additionally, we used the DIVA-Bayes data from Aesculus to quantify the effects on biogeographic inference of including two wildcard fossil taxa in phylogenetic analysis. Our analysis resolved the geographic ranges of the parental nodes of the lineages of Aesculus with moderate to high probabilities. The probabilities were greater than those estimated using the simple calculation of pp ∗ F(ry) at a statistically significant level for two of the six lineages. We also found that adding fossil wildcard taxa in phylogenetic analysis generally increased P for ancestral ranges including the fossil's distribution area. TheP was more dramatic for ranges that include the area of a wildcard fossil with a distribution area underrepresented among extant taxa. This indicates the importance of including fossils in biogeographic analysis. Exmination of range subdivision at the parental nodes revealed potential range evolution (extinction and dispersal events) along the stems of A. californica and sect. Parryana.
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Phylogeny, origin, and biogeographic history of Aesculus L. (Sapindales) - an update from combined analysis of DNA sequences, morphology, and fossils
TAXON, 2009Co-Authors: Aj Harris, Qiu-yun Jenny Xiang, David T. ThomasAbstract:Conflicting phylogenies and biogeographic hypotheses for Aesculus L. were reevaluated using data integrating morphology, fossils, and DNA sequences. A more robust phylogeny of Aesculus was constructed by increasing taxon and character sampling to include 42 morphological characters and five DNA regions including rpsl6, trnHK, matK, ITS, and part of the LEAFY gene. Our analyses revealed three well-supported major lineages in Aesculus. These are sect. Calothyrsus excluding A. californica, sect. Macrothyrsus + A. californica, and sect. Aesculus + sect. Pavia + sect. Parryana. The relationship of sect. Aesculus to sect. Parryana + sect. Pavia is strongly supported and previously unreported. Relationships among the three major clades remained incompletely resolved. Biogeographic and divergence time analyses using DIVA and Multidivtime support a Paleocene origin of Aesculus in eastern Asia and western North America, and showed that the genus subsequently dispersed into eastern North America, Central America, and Europe. Our results support that Aesculus originated as an element of the Paleogene mesophilic flora in the Beringian region with multiple eastward migrations characterizing the early spatial history of this genus. This biogeographic history supports Trans-Beringian migration of plants in the very early Paleogene.
Salih Maden - One of the best experts on this subject based on the ideXlab platform.
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Phytophthora na Aesculus hippocastanum L. (jírovec maďal)
2013Co-Authors: Sabine Werres, Seçil Akilli, Salih MadenAbstract:Aesculus hippocastanum L. (Jirovec maďal) představuje v Evropě významnou dřevinu parků, aleji a zahrad. Roste předevsim v mirnem podnebnim pasmu (mapa výskytu viz http://www.discoverlife.org). Jirovec maďal nepatři mezi původni dřeviny středni Evropy. Jeho původem jsou horske lesy Řecka, Albanie a Bulharska, odkud byl introdukovan do zapadni Evropy již v průběhu sestnacteho stoleti. Jirovec dosahuje věku až 200 let. Aesculus hippocastanum existuje v několika odlisných kultivarech jako jsou ‘Baumannii‘, ‘Globosum’ a ‘Pyramidalis’. Aesculus hippocastanum je rovněž rodicovským druhem cerveně kvetouciho hybridu A. x carnea (Cervený Jirovec maďal). Znamým je kultivar tohoto hybridu ‘Briottii’.
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Phytophthora em Aesculus hippocastanum L. (castanheiro da índia)
2013Co-Authors: Sabine Werres, Seçil Akilli, Salih MadenAbstract:Na Europa Aesculus hippocastanum L. (castanheiro-da-india) e uma especie arborea muito utilizada na beira das estradas, nos parques, nos becos e nos jardins. Esta arvore cresce predominantemente em zonas de clima temperado (mapa da distribuicao de A. hippocastanum ver http://www.discoverlife.org). O castanheiro-da-india nao e uma especie nativa da Europa Central. E originaria das florestas montanhosas da Grecia, Albânia e Bulgaria a partir de onde foi introduzida na zona ocidental durante o sec.XVI. O castanheiro-da-india pode atingir a idade de 200 anos. Existem diferentes cultivares de Aesculus hippocastanum: Baumannii,‘Globosum’ e ‘Pyramidalis’. Aesculus hippocastanum* e um parente do hibrido de flor vermelha A. x carnea* (castanheiro vermelho da india), sendo “Briottii” uma das suas cultivares mais famosas. *Cultivadas em parques e areas urbanas em Portugal.
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Phytophthora on Aesculus hippocastanum L. (horse chestnut) / 2nd revised edition
2013Co-Authors: Sabine Werres, Seçil Akilli, Salih MadenAbstract:In Europe Aesculus hippocastanum L. (horse chestnut) is an important tree species in the roadside, in parks, alleys and in gardens. This tree species grows predominately in the temperate climatic zones (distribution map for A. hippocastanum see http://www.discoverlife.org). Horse chestnut is non-native in Central Europe. It originated from mountain forests in Greece, Albany and Bulgaria from where it was introduced to the western parts via Vienna by humans in the 16th century. Horse chestnuts can reach a maximum age of around 200 years.There are different cultivars of Aesculus hippocastanum like ‘Baumannii’, ‘Globosum’ and ‘Pyramidalis’. Aesculus hippocastanum is also a parent of the red flowering hybrid A. x carnea (Red Horse Chestnut). A famous cultivar of this hybrid is ‘Briottii’.
Alshamrani Rahma - One of the best experts on this subject based on the ideXlab platform.
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DNA barcoding of a complex genus, Aesculus L. (Sapindaceae) reveals lack of species-level resolution
NRC Research Press (a division of Canadian Science Publishing), 2019Co-Authors: Aygoren Uluer Deniz, Alshamrani RahmaAbstract:Aesculus L. is a small genus of horticulturally important trees and shrubs, comprising 13–19 species. Frequent hybridization among species, particularly in cultivation, has contributed to taxonomic confusion and difficulties in the identification of plants. In this study, we evaluated three widely employed plant DNA barcode loci, matK, and the entire ITS region (ITS1+5.8S+ITS2) as well as subunit ITS2 for 50 individuals representing 13 species of Aesculus, excluding only A. wangii (=A. assamica). In contrast to the plastid matK region, both the ITS and ITS2 loci displayed low levels of species discrimination, especially in our “first hit” BLASTn searches. We also presented the phylogeny of Aesculus based on matK and the entire ITS region, with additional matK and ITS sequences from GenBank. Our results show that Aesculus chinensis, A. flava, A. glabra, A. pavia, and A. sylvatica are probably not monophyletic. Furthermore, with the widest taxon coverage until now, the current study highlights the importance of sampling multiple individuals, not only for DNA barcoding, but also for phylogenetic studies.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
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DNA barcoding of a complex genus, Aesculus L. (Sapindaceae) reveals lack of species-level resolution
'Canadian Science Publishing', 2019Co-Authors: Uluer, Deniz Aygoren, Alshamrani RahmaAbstract:WOS: 000484284400004Aesculus L. is a small genus of horticulturally important trees and shrubs, comprising 13-19 species. Frequent hybridization among species, particularly in cultivation, has contributed to taxonomic confusion and difficulties in the identification of plants. In this study, we evaluated three widely employed plant DNA barcode loci, matK, and the entire ITS region (ITS1+5.8S+ITS2) as well as subunit ITS2 for 50 individuals representing 13 species of Aesculus, excluding only A. wangii (=A. assamica). In contrast to the plastid matK region, both the ITS and ITS2 loci displayed low levels of species discrimination, especially in our "first hit" BLASTn searches. We also presented the phylogeny of Aesculus based on matK and the entire ITS region, with additional matK and ITS sequences from GenBank. Our results show that Aesculus chinensis, A. flava, A. glabra, A. pavia, and A. sylvatica are probably not monophyletic. Furthermore, with the widest taxon coverage until now, the current study highlights the importance of sampling multiple individuals, not only for DNA barcoding, but also for phylogenetic studies
Dušica Ćalić - One of the best experts on this subject based on the ideXlab platform.
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Comparative Study of Antioxidant Status in Androgenic Embryos of Aesculus hippocastanum and Aesculus flava
The Scientific World Journal, 2014Co-Authors: Dubravka Štajner, Boris Popović, Dušica Ćalić, M. ŠtajnerAbstract:In vivo (leaves and seed embryos) and in vitro (androgenic embryos) antioxidant scavenging activity of Aesculus hippocastanum and Aesculus flava medical plants was examined. Here we report antioxidant enzyme activities of superoxide dismutase, catalase, guaiacol peroxidase and glutathione peroxidase, reduced glutathione quantity, flavonoids, soluble protein contents, quantities of malondialdehyde, and •OH radical presence in the investigated plant samples. Total antioxidant capacity of all the samples of A. hippocastanum and A. flava was determined using FRAP, DPPH, and NO• radical scavenger capacity. The leaves of A. flava collected from the botanical garden exhibited stronger antioxidant activity (higher activities of SOD, and higher quantities of GSH, TSH, TPC, and scavenging abilities of DPPH and NO•, and higher FRAP values and lowest quantities of •OH and MDA) than in vitro obtained cultures. However, the leaves of A. flava showed higher antioxidant activity than the leaves of A. hippocastanum, and therefore they have a stronger tolerance of oxidative stress. Androgenic embryos of both species had low amount of antioxidants due to controlled in vitro environmental conditions (T, photoperiod, humidity, nutritive factors, and pathogen-free). Our results confirmed that we found optimal in vitro conditions for producing androgenic embryos of both Aesculus species. Also, we assume that horse chestnut androgenic embryos can be used as an alternative source for large-scale aescin production.
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The effect of low temperature on germination of androgenic embryos of Aesculus hippocastanum L.
Biologia plantarum, 2005Co-Authors: Dušica Ćalić, Snežana Zdravković-korać, D. Pemac, Lj. RadojevićAbstract:Treating androgenic embryos of Aesculus hippocastanum L. with low temperatures (6 °C) improved their germination and regeneration into plantlets. The embryos derived from anther cultures showed better results than those derived from microspore cultures.
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Secondary embryogenesis in androgenic embryo cultures of Aesculus hippocastanum L.
Biologia plantarum, 2005Co-Authors: Dušica Ćalić, Snežana Zdravković-korać, Lj. RadojevićAbstract:Secondary somatic embryos appeared on the cotyledons and radiculi of embryos derived from suspension and anther cultures of Aesculus hippocastanum L. The highest number of secondary somatic embryos formed on a hormone-free medium.
