Species Of Aster Research Articles

Phylogenetic relationships and generic delimitation of Eurasian Aster (Asteraceae: Astereae) inferred from ITS, ETS and trnL-F sequence data

The classification and phylogeny of Eurasian (EA) Aster (Asterinae, Astereae, Asteraceae) remain poorly resolved. Some taxonomists adopt a broad definition of EA Aster, whereas others favour a narrow generic concept. The present study aims to delimit EA Aster sensu stricto (s.s.), elucidate the phylogenetic relationships of EA Aster s.s. and segregate genera. The internal and external transcribed spacers of nuclear ribosomal DNA and the plastid DNA trnL-F region were used to reconstruct the phylogeny of EA Aster through maximum parsimony and Bayesian analyses. The analyses strongly support an Aster clade including the genera Sheareria, Rhynchospermum, Kalimeris (excluding Kalimeris longipetiolata), Heteropappus, Miyamayomena, Turczaninowia, Rhinactinidia, eastern Asian Doellingeria, Asterothamnus and Arctogeron. Many well-recognized species of Chinese Aster s.s. lie outside of the Aster clade. The results reveal that EA Aster s.s. is both paraphyletic and polyphyletic. Sheareria, Rhynchospermum, Kalimeris (excluding K. longipetiolata), Heteropappus, Miyamayomena, Turczaninowia, Rhinactinidia, eastern Asian Doellingeria, Asterothamnus and Arctogeron should be included in Aster, whereas many species of Chinese Aster s.s. should be excluded. The recircumscribed Aster should be divided into two subgenera and nine sections. Kalimeris longipetiolata, Aster batangensis, A. ser. Albescentes, A. series Hersileoides, a two-species group composed of A. senecioides and A. fuscescens, and a six-species group including A. asteroides, should be elevated to generic level. With the Aster clade, they belong to the Australasian lineages. The generic status of Callistephus should be maintained. Whether Galatella (including Crinitina) and Tripolium should remain as genera or be merged into a single genus remains to be determined. In addition, the taxonomic status of A. auriculatus and the A. pycnophyllus-A. panduratus clade remains unresolved, and the systematic position of some segregates of EA Aster requires further study.

Establishment of Aster sedifolius and Aster caucasicus callus cultures as a potential source of antioxidants

Callus cultures were established for Aster sedifolius and Aster caucasicus, two Aster species used in natural medicine for their anticancer, antibacterial and antiviral activities attributed to the high content of antioxidant compounds such as polyphenols and ascorbate. The effects of growth medium and light condition on the induction and growth rate of callus from leaf, petiole and root explants are reported. Callus induction and proliferation depended on the genotype and the experimental conditions. In particular, a profuse callus culture was obtained from leaf explants grown in the light on medium supplemented with 2,4-D (0.1 mg l−1) for A. caucasicus and on medium supplemented with 2,4-D (0.44 mg l−1) plus 6-benzil-ammino-purine (BAP) (0.22 mg l−1) for A. sedifolius. The content of total polyphenol and ascorbic acid was estimated in leaf and petiole explants of in vivo plants and in the relative derived calli. In calli, polyphenol content was lower than in the corresponding in vivo organs. Furthermore, the total ascorbic acid content decreased in calli while the reduced ascorbic acid pool increased. These findings demonstrate that Aster callus cultures produce antioxidant compounds and as such might be a model system to investigate the regulation and production of these important metabolites.

Phytochemical and Biological Studies on Aster novi-belgii

Aster is a large genus of the family Asteraceae (Compositae) comprising more than 200 species distributed around the world (1). Some of Aster species have been used in traditional medicine for the treatment of fever, cold, tonsillitis, snake bite and bee sting (2). Members of this genus are rich in triterpenoid saponins, two oleanan type saponins and three flavonoid compounds were isolated from Aster novi (3,4). Phytochemical investigation of the methanolic extract of Aster novi-belgii L. (Asteraceae) aerial part has led to the isolation and identification by spectroscopic means of four triterpenoid saponins, oleanolic acid 3-O-β-D-galactopyranosyl (1→3)-α-L-arabinopyranoside; 3-O-β-D- glucopyranosyl- 3β, 16 α- dihydroxyolean- 12- en- 28-oic acid-28-O-α-L- arabinopyranoside; {3-O-β-D- glucouronopyranosyl- 3β,16 α- dihydroxyolean- 12-en -23-oic acid 28-O-β-D- xylopyranosyl- (1→3)-β-D- xylopyranosyl- (1→4)- α-L-rhamnopyranosyl-(l→2)-α-L-arabinopyranoside} ester and {3-O-β-D-glucouronopyranosyl-3β,16 α- dihydroxyolean- 12-en- 23-oic acid 28-O-β-D- xylopyranosyl- (1→3)- β-D-xylopyranosyl (1→4)- [α-L- arabinopyranosyl- (1→3)] -α-L- rhamnopyranosyl- (l→2)- α-L-arabinopyranoside} ester, and four flavonoids; kaempferol, quercetin, kaempferol 3-O-β-D-glucopyranoside and quercetin 3-O-β-D-glucopyranoside. Moreover, the extract showed a molluscicidal activity against Biomphalaria alexandrina snails.

Relative Pollinator Effectiveness of Insect Floral Visitors to Two Sympatric Species of Wild Aster: Symphyotrichum lanceolatum (Willd.) Nesom and S. lateriflorum (L.) Löve & Löve (Asteraceae: Astereae)

Four parameters were used to determine pollinator effectiveness of floral visitors to two sympatric species of Symphyotrichum (S. lanceolatum and S. lateriflorum): (1) pollinator efficiency; (2) relative abundance of visitors; (3) amount of pollen carried on a visitor's body; and (4) visitor foraging time per capitulum. The most effective pollinators of S. lanceolatum were Apis mellifera (Apidae), Eristalis spp. (Syrphidae), Dolichovespula arenaria, and Polistes fuscatus (both Vespidae). Halictidae (sweat bees) and Tachinidae (Diptera) were also potentially effective pollinators. For S. lateriflorum, effective pollinators included D. arenaria, Vespula maculifrons (Vespidae), Lasioglossum spp. (Halictidae), and A. mellifera, with large syrphid flies also having moderate importance. The Halictidae was the only group of visitors that demonstrated a significant difference in the amount of time spent foraging the floral heads of these two aster species. Despite spending more time foraging the floral heads of S. lateriflorum, halictid bees carried the same average pollen load regardless of the species of Symphyotrichum from which they were collected. Halictid bees, however, are potentially more effective pollinators of S. lateriflorum than of S. lanceolatum.

Authenticating and distinguishing the eight species of traditional Tibetan medicine “Meiduoluomi” by microscopic technique

Because of the morphological and macroscopic similarity, many species of Erigeron and Aster (Asteraceae) are confusable and usually used under the same name "Meiduoluomi" in traditional Tibetan medicine (TTM). To find an easy, quick, and reliable method to authenticate and distinguish the eight main medicinal plants of these species, the light microscope was used to reveal the morphoanatomic details. The fixed, sectioned, and stained plant materials and epidermis materials were studied by microscopic techniques. The results of the microscopic features are systematically described and illustrated, and comparison parameters are presented. Furthermore, a key to the eight species of "Meiduoluomi" was constructed. Microscopy can be unambiguously used to authenticate and distinguish the eight main species of TTM "Meiduoluomi."

Differences in AM fungal root colonization between populations of perennial Aster species have genetic reasons

We tested the hypothesis whether differences between plant populations in root colonization by arbuscular mycorrhizal (AM) fungi could be caused by genetic differentiation between populations. In addition, we investigated whether the response to AM fungi differs between plants from different populations and if it is affected by the soil in which the plants are cultivated. We used Aster amellus, which occurs in fragmented dry grasslands, as a model species and we studied six different populations from two regions, which varied in soil nutrient concentration. We found significant differences in the degree of mycorrhizal colonization of plant roots between regions in the field. To test if these differences were due to phenotypic plasticity or had a genetic basis, we performed a greenhouse experiment. The results suggested that Aster amellus is an obligate mycotrophic plant species with a high dependency upon mycorrhiza. Plant biomass was affected only by soil, and not by population or the interaction between the population and the soil. Mycorrhizal colonization was significantly affected by all three factors (soil, population, interaction of soil and population). Plants from the population originating from the soil with lower nutrient availability developed more mycorrhiza even when grown in soil with higher nutrient availability. The correspondence between mycorrhizal colonization of plants in the field and in both soils in the pot experiment suggests that the observed differences in root colonization have a genetic basis.

Light reduction predicts widespread patterns of dominance between asters and goldenrods

Here we investigate the long-cited pattern that throughout the eastern United States, Solidago species (goldenrods), and in particular S. canadensis displace Aster species and dominate old-field communities. Theory predicts that such a ubiquitous pattern of repeated dominance should be linked to competitive ability for a limiting resource. However, no one has investigated this possibility in old-fields, representing a potentially significant gap in our understanding of a common human-altered environment. We tested the hypothesis that S. canadensis is the superior competitor for light compared to other common co-occurring goldenrod species, and that the goldenrods in general are the superior competitors for light compared to coexisting aster species, which are typically less abundant. We tested this hypothesis by comparing the light attenuation abilities of four goldenrod species, S. canadensis, S. rugosa, S. gigantea, and Euthamia graminifolia, and three aster species, Aster novae-angliae, A. pilosus, and A. prenanthoides. Consistent with our hypothesis, S. canadensis had a greater ability to attenuate light than any of the other goldenrods at higher densities, and the goldenrods overall had a greater ability to attenuate light than the asters. By conducting a census in our study area, we verified that S. canadensis is locally the most abundant goldenrod and that goldenrods are more locally abundant than asters. Furthermore, by conducting a literature survey we found evidence that S. canadensis replaces A. pilosus through time. Thus we found a close correspondence between relative abundance in the field and light attenuation ability in field experiments. These results are consistent with theory predicting that competition for limiting resources, in this case light, explains patterns of dominance and relative abundance in old-field plant communities.

Influence of the photoperiod, daminozide application and fertilization on New England aster

The species Aster novae-angliae L., New England aster, is a short day perennial, flowering from the end of August to the end of October. It is branched out and reaches a height to 1.2 m. New England aster is grown in gardens and for cutting production. It has a flowering pot plant potential, but many of its cultivars are too tall to be grown in pots. Regulation of the day length may affect its flowering period while the application of growth retardants may regulate the shoot length and branching, as well as induce flowering in this Aster species. Growth regulators are applied in floriculture to reduce the vegetative growth of plants and to improve their aesthetic value by inducing shorter internodes (Gibson and Whipker, 2003 ; Marosz and Matysiak, 2005 ; Pinto et al. 2005 ; Pobudkiewicz and Treder, 2006). Balanced nutrition is an important tool in cultivation of agricultural plants as well as for flowering pot plants and it has to be adjusted to the plant requirements during particular development stages for which only orientational values are available for the majority of ornamental plants (Macz et al. 2001 ; Kant et al. 2005 ; Berzsenyi and Dang, 2006 ; Sharma and Sharma, 2006 ; ). The objectives of this work are to define the possibility of growing Aster novae-angliae L., ‘ September Ruby’ , as a flowering pot plant in the late summer period, determine the effect of day length and the cultivar’ s response to one time application of growth retardant, as well as topdressing with liquid mineral fertilizer on its growth and flowering.

A comparison of two North-American asters invading in central Europe

Perennial North-American asters have become common in central Europe since the 17th century when they started to be cultivated as ornamental plants. Today, they are widely spreading especially in alluvial sites in lowlands. Two of the most common aster species, Aster lanceolatus and Aster novi-belgii, were investigated for their generative reproduction, including seed production and germination, and vegetative propagation (growth of rhizomes). Experimental sites with and without competition from the surrounding vegetation were used to test for differences between the species. Germination experiments showed that the asters produced a relatively high number of viable and easily dispersed seeds, which often germinated immediately after ripening and usually did not require any special treatment. Some aster clones produced more than 100 new rosettes from one initial rosette within a year. Apparently, asters are able to form large polycorms in a relatively short time. However, their rapid vegetative spread can be reduced by competition from established vegetation.

Bioactive Saponins from Allium and Aster Plants

Plants belonging to the genera Allium and Aster are widely distributed in nature and have been used as food and/or medicine. Their wide use was mainly due to the medicinal properties attributed to these plants since ancient times, recently supported by epidemiological and laboratory studies. Saponin compounds, responsible for many pharmacological activities, are quite abundant in these plants. Thus, a deep knowledge about the saponin composition of these vegetables appears to be essential and could promote the discovery of new potential leads. As part of our continuing research aimed at the identification of bioactive metabolites, we have addressed our attention to several Allium and Aster species. The study resulted in the isolation of over fifty saponins of furostane, spirostane, cholestane, and oleane-type structures. Some of the isolated compounds exhibited promising antiproliferative, antifungal, and antispasmodic activities. Their structure, distribution and bioactivity will be reported here together with a brief overview of the literature on Allium and Aster saponins.

(269) Taxonomic Relationship of Korean Native Aster, Based on Internal Transcribed Spacer (ITS) Sequences of Nuclear Ribosomal DNA

There are 25 species of aster in Korea. There is a controversy about the taxonomical classification of Aster. The genus Aster was classified into four genera, Aster, Gymnaster, Kalimeris, and Heteropappus, by morphological characters. In order to clarify the phylogenetic position of aster, the nucleotide sequence of the nuclear ribosomal DNA internal transcribed spacer (ITS) region was compared among 11 taxa in Korean native aster. The size of ITS1 and ITS2 ranged from 283 to 286 bp and from 251 to 257 bp, respectively. The size of 5.8S region was 164 bp in 11 taxa. The total length of ITS1, 5.8S and ITS2, A. tripolium was shown to be the shortest length, 701 bp; and A. scaber was shown to be the longest length, 706 bp. The G+C content of ITS1 ranged from 47.9% to 51.2% and ITS2 ranged from 52.2% to 55.1%. The range of each taxon was narrow. The total length of the character matrix was 708 characters. Among them, total indel showed 9; in the ITS1 region indel showed 6 it was 67%; and in the ITS2 region, indel showed 3. Most of the indels showed deletion or insertion of only one base pair, but in A. spathulifolius deleted two base pairs and in A. tripolium deleted five base pairs. But in A. yomena, A. hayatae, A. koraiensis, and A. hispidus, the indel was not detected. Phylogenetic trees did not even make a difference inter-genus, but A. yomena and A. koraiensis called genus Kalimeris and genus Gymnaster, respectively; these constituted a clade. A. hispidus called genus Heteropappus was placed as a sister group to the clade of A. ageratoides and A. glehni.

Genetic relationships among Aster species by multivariate analysis and AFLP markers.

Fourteen species of Aster were characterized for morphological traits of commercial interest, chromosome number and genetic diversity by AFLP markers to exploit this material not only for breeding purposes but also as source of pharmaceuticals. The variation observed among the Aster species for five morphological traits was summarized by means of discriminant analysis. Three significant canonical variables, accounting for about 96% of total variance, were mainly correlated with capitulum diameter, number of ligulae and leaf length. The morphological variation appeared related to ploidy level of the species. A diploid chromosome number ranging from 10 to 18 was evident in seven species whereas the other species are polyploids with variable chromosome numbers up to 52. The pollen production and stainability were quite variable among Aster species. Furthermore, seven species produced big pollen grains besides normally-sized ones, at a frequency ranging from 1 to 12%, possibly due to 2n pollen production. The possibility that evolution of Aster genus could be driven by 2n gametes and sexual polyploidization is discussed. Implications of 2n gametes for Aster breeding are also mentioned. AFLP analysis of the fourteen Aster species based on six primer combinations revealed a total number of 421 polymorphic amplified DNA fragments. The genetic similarities estimated between the Aster species, based on both shared and unique amplification products ranged from 0.335 to 0.604 across all species and revealed a geographically based clustering within the genus. The highest similarity was detected between A. alpinus and A. amellus with Eurasian origin.

Aster shennongjiaensis (Asteraceae), a new species from central China

A new species of Aster (Asteraceae) from China, Aster shennongjiaensis W. P. Li et Z. G. Zhang, is described and its morphology and karyotype illustrated. Aster shennongjiaensis is apparently endangered, presently known only from one small population in bamboo forests of Shennongjia Reserve in central China. On a morphological basis, the closest species to A. shennongjiaensis is A. lasiocladus Hayata, but they are quite different in many features. The morphological characteristics of the two species are compared. Karyotype of the new species is described and formulated as 2n = 2x = 18 = 16m + 2sm.

Morphological, karyological, and molecular analysis in Aster spp. (Asteraceae)

Two species of the genus Aster L. from Nepal have been studied and compared with a common European species A. alpinus L. The aim was to verify the specific taxonomic classification and to characterize the aster populations on the basis of morphological, karyological, and molecular analysis.

Consequences of achene biomass, within-achene allocation patterns, and pappus on germination in ray and disc achenes of Aster umbellatus var. umbellatus (Asteraceae)

A familiar floral dimorphism that may have an associated seed heteromorphism, that is, the production of seeds with variable morphologies and ecological strategies, is the presence of both ray and disc florets in the capitula of most Asteraceae. Achenes of Aster umbellatus var. umbellatus Mill. were separated into the ray or disc type with either the pappus remaining attached and intact, or removed. Differential allocation of biomass between ray and disc achenes or heavy and light achenes was not observed. Germination was relatively low (disc achenes with pappus removed, 16.7%; ray achenes with pappus removed, 22.9%; disc achenes with pappus intact, 7.3%; and ray achenes with pappus intact, 7.2%) for each. Although achene weight did not affect the likelihood of germination, germination was 2.5-3 times greater among disc and ray achenes, respectively, for which the pappus was removed as opposed to intact. These results do not conform with previous thoughts relative to the advantageous role of the pappus in germination. As such, I suggest that in this species of Aster the key role of the pappus is to facilitate dispersal as opposed to encourage germination. Furthermore, the production of morphologically and ecologically indistinguishable ray and disc achenes by A. umbellatus var. umbellatus would suggest that the significance of heterogamous capitula, specifically the production of ray florets, rests in their attractiveness of pollinators.Key words: within-achene allocation patterns, germination, Aster.

Floral sex ratios and gynomonoecy in Aster (Asteraceae)

Gynomonoecy is the sexual system in which female and bisexual flowers occur on the same plant. This system has received little attention despite the considerable work on other plant sexual systems in the past few decades. Our study examines one hypothesized advantage of having two flower types on a plant, namely that this arrangement permits flexibility in allocation of resources to male and female reproductive functions. We examined 16 species of Aster (Asteraceae), a genus of gynomonoecious, perennial herbs. Plants in this genus produce heads consisting of a whorl of female flowers around a cluster of bisexual flowers. Among field-grown plants we found no evidence that plant size, date, position of heads, rainfall, or shade influenced the proportion of female flowers. A series of greenhouse experiments likewise revealed no large or consistent effects of light, nutrients, or position of heads on the proportion of ray flowers. While floral ratios proved very stable in the face of environmental and physiological variables, they exhibited significant variation among plants and among sibships in most species. We conclude that the presence of two flower types in gynomonoecious asters is not advantageous in permitting flexibility in allocation of resources to male and female functions. We believe that the advantage of the female flowers in aster heads lies either in reducing pollen-pistil interference or in attracting pollinators.

A chloroplast-DNA phylogeny ofKalimeris andAster, with reference to the generic circumscription

RFLPs of cpDNA of five species and one variety ofKalimeris, and elght species ofAster from Japan were investigated. Approximately 290 restriction sites were surveyed using 16 restriction enzymes. A total of 52 restriction site mutations was detected, and 21 of them were phylogenetically informative. Wagner parsimony analysis resulted in only one most parsimonious tree. In the tree obtained,Kalimeris sensu Kitamura is a colyphyletic group;K. miqueliana belongs to a different clade than the remaining species ofKalimeris. This result suggests that the shortening of the pappus has occurred in parallel in different evolutionary line. Thus, it is not appropriate to extend the generic circumscription ofKalimeris to includeK. miqueliana, based on pappus length. The sister group ofKalimeris, exceptK. miqueliana, is theAster ageratoides group.Aster ovatus is included in theKalimeris clade and it is suggested that it represents an amphidiploid with someKalimeris species as its maternal parent.

A Molecular Systematic Study and Taxonomic Revision of Psilactis (Asteraceae: Astereae)

Intergeneric and interspecific relationships of Psilactis were studied using data from restriction site analysis of chloroplast DNA and nuclear rDNA. Molecular evidence supports the removal of Psilactis from Machaeranthera and its alliance with Aster. Within the Aster lineage, chlo- roplast DNA data support an alliance composed of members of Psilactis that have n = 4 (P. tenuis, P. boltoniae) and those of Aster subg. Oxytripolium that are based on x = 5 (A. subulatus, A. tenuifolius), separating them from the n = 9 species of both Aster and Psilactis. Evidence from nuclear rDNA, in contrast, supports different alignments by combining n = 4 and n = 9 species of Psilactis and by allying the n = 5 and n = 10 species of Aster subg. Oxytripolium with other species of Aster. Comparison of cpDNA results with evidence from morphology, rDNA, and isozymes suggests that hybridization may account for some relationships supported by chloroplast DNA. Psilactis is re-established as a distinct genus of six species, with P. mexicana placed in synonymy under P. gentryi. The following new taxonomic combinations are made: Psilactis gentryi, Psilactis odysseus, and Psilactis hetero- carpa.

Aster and Brachyactis in Illinois

The need for a comprehensive study and taxonomic revision of asters in Illinois becomes apparent when one looks at the varied treatments of this genus in the principal floristic literature of the state (G.N. Jones 1945, 1950, 1963; Jones and Fuller 1935: Mohlenbrock 1975. 1986; Mohlenbrock and Ladd 1978. Three factors contribute to the differences found in these works: the number of taxa recorded for Illinois, nomenclatural considerations such as those dictated by the principle of priority, and differences in taxonomic concepts and interpretations. In the first edition of Flora of Illinois (G.N. Jones 1945). 33 species are treated under Aster, not counting hybrids. Three additional species appear in the third edition (G.N. Jones 1963): A. chasei G.N. Jones in Jones & Fuller, a species newly described from Illinois: A. tartaricus L.f.. an occasionally escaped cultivated species; and A.parviveps (Burgess in Britton & Brown) Mack. & Bush, probably inadvertently omitted from the first two editions but included in Jones and Fuller (1955). In the most recent (Guide to the Vascular Flora of Illinois. Mohlenbrock (1986) treats 35 species. A notable change involves the transfer of A. ptarmicoides (Nees) Torrey & Gray to Solidago. In this revision, I recognize 31 species of Aster in the state of Illinois. My research has concentrated on New World and some Old World species of Aster (sensu lato) forever 15 years (A.G. Jones 1974, 1977, 1978a, b, c. I980a, b, 1982, 1983,1984, 1987; Jones and Hiepko 1981; Jones and Young 1983; Jones and Lowry 1986; and others), and much additional infomation has been introduced in this current study. My taxonomic concepts are summarized in the conspectus of classification of Illinois Aster species.

The Status of Aster commixtus and a New Species of Aster from the Southeastern United States

Multivariate statistical techniques are used to show that the type specimen of Eurybia commixta Nees (=Aster commixtus (Nees) Kuntze) belongs to A. spectabilis Aiton. The two species are, therefore, conspecific and the names E. commixta and A. commixtus are later synonyms for A. spectabilis. Statistical analyses also demonstrate that the plants native to the southeastern United States to which the name A. commixtus has been applied do not belong to A. spectabilis, but to two other distinct species, the diploid A. mirabilis Torrey & A. Gray, and a previously unnamed hexaploid species, A. jonesiae Lamboy, described here as new. Historically, Aster commixtus (Nees) Kuntze has always been placed in or close to the group now known as Aster sect. Biotia DC. ex Torrey & A. Gray (Lamboy and Jones 1987a), but both the origin and the identity of the species have been uncertain. Nees von Esenbeck (1832) orig- inally described the species as Eurybia commixta, placing it (along with Aster macrophyllus L., A. schreberi Nees, A. corymbosus Aiton, and another new species, E. glomerata Bernh. ex Nees) in the Genuinae group of the genus Eurybia (Cass.) Cass. in Cuvier. His description of E. commixta was based on a plant of unknown provenance that had been grown in the Bonn Botanical Garden. Nees characterized the species as follows: rad- ical leaves narrow; lower cauline leaves ovate; upper cauline leaves oblong-lanceolate, ses- sile, serrate, viscid-scabrous; capitulescence branched; phyllaries squarrose; pubescence glutinous (i.e., stipitate-glandular). No holo- type of this name exists, but an authentic Nees specimen has recently been designated as the lectotype (Lamboy and Jones 1987b). From Nees's Genuinae group in Eurybia, de