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Marcel Rejmanek – One of the best experts on this subject based on the ideXlab platform.
small genomes and large seeds chromosome numbers genome size and seed mass in diploid Aesculus species sapindaceaeAnnals 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.
The complete chloroplast genome of vulnerable Aesculus wangii ( Sapindaceae ), a narrowly endemic tree in Yunnan, ChinaConservation 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.
Testing the monophyly of Aesculus L. and Billia Peyr., woody genera of tribe Hippocastaneae of the SapindaceaeMolecular 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.
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.
Salih Maden – One of the best experts on this subject based on the ideXlab platform.
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’.
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.
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’.