Chromosome numbers of goldenrods, Euthamia and Solidago (Compositae-Astereae)

2013

Acta Soc Bot Pol

Species from genus Solidago are exceptionally successful worldwide invaders from North America [1]. Among about 120 Solidago species three are invaders, which so far have conquered Europe, large parts of Asia, Australia and New Zealand [2].In central Europe five representatives of the Solidago genus are found. Only one species (S. virgaurea L.) is native, while the other four are of American origin, namely: S. gigantea Aiton, S. canadensis L., S. altissima L. [S. canadensis var. scabra (Muhl.) Torr. and Gray] and S. graminifolia (L.) Elliot [3]. Three of the introduced taxa (S. gigantea, S. canadensis and S. altissima) are invasive and morphologically similar to each other. Their taxonomic status in Europe has been discussed [3][4][5][6][7][8]. The range of the fourth alien species, S. graminifolia, is small and limited to few locations in Europe [9,10].The basic chromosome number in Solidago species is x = 9. S. virgaurea and S. graminifolia are diploids (2n = 18). S. canadensis consists of diploid (2n = 18) and tetraploid plants (2n = 36), and S. altissima hexaploid (2n = 54), triploid (2n = 27) and tetraploid (2n = 36) plants of native origin [11,12]. While in Europe only diploid plants of these species are noted [7,13], in case of Solidago altissima the occurrence of additional Bchromosomes was observed [14,15]. Solidago gigantea occurs in three different cytotypes: diploid (2n = 18), tetraploid (2n = 36) and hexaploid (2n = 54), which represent the whole S. gigantea complex in native range and has also been found in Europe [16]. However, according to current data [17][18][19] in Europe only tetraploid populations of S. gigantea are known. Therefore, based on this variety in chromosome number, considerable morphological variety in these taxa could be expected [20]. It could also include differentiation in traits related to invasiveness as, e.g. stem height or inflorescence size [21].Several hypotheses focus on the reasons why alien invasive plants are more successful than other plants in occupying new areas [22][23][24][25]. There are numerous confirmations, that plants in the new range could differ from their ancestors, including AbstractInvasive plants in their new range can differ from their ancestors, including traits ultimately influencing habitat preferences, competitiveness and dispersal ability. In Europe Solidago species are considered as one of the worst invaders of American origin. In this study the frequency of occurrence of Solidago species, their soil preferences and morphological diversity, in Silesia (southwestern Poland, Central Europe) were surveyed. On the basis of phytosociological relevés, made using the Braun-Blanquet method, in 75 plots, we determined the composition of species co-occurring with particular Solidago species. The height of ramets, as well as length and width of inflorescences of Solidago species were measured. We also determined the basic soil properties and noted the presence of trees overshading the ground vegetation. The compositional variation of vegetation and its r...

Section: Study Speciesmentioning

confidence: 99%

mentioning

confidence: 99%

Soil preferences and morphological diversity of goldenrods (Solidago L.) from south-western Poland

2013

Acta Soc Bot Pol

“…In America, this species is referred to as Euthamia graminifolia (L.) Nutt. on the basis of anatomy and DNA studies (Semple et al 1981;Semple et al 1984;Abrahamson et al 2005). The remaining taxa are morphologically similar to each other.…”

Section: Study Speciesmentioning

confidence: 91%

Do Landscape Structure and Socio-Economic Variables Explain the Solidago Invasion?

Świerszcz

2016

Folia Geobot

Biological invasions are considered a major threat to biodiversity on a global scale. In this study, we examined the effect of landscape structure and socioeconomic variables on the invasion pattern of alien Solidago species. Field data were collected in a set of 309 sampling plots, regularly placed on the intersecting lines of a 10 × 10-km grid, in south-western Poland (Silesia, Central Europe). Landscape characteristics and average values of socio-economic variables, such as human population density and total income per capita, were calculated. To examine the effect of landscape structure across different spatial extents, the landscape characteristics were analysed for three different buffers (radius: 500 m, 2 km and 5 km). A model explaining the pattern of the invasion was developed using a univariate, binary classification (decision) tree. The results show that both landscape structure and density of human population explain the spatial pattern of the invasion by alien Solidago species. The pattern was mostly shaped by the presence of unsuitable (forests) and suitable (roadsides) habitats for Solidago. The influence of percentage forest cover and road length was the strongest at the small spatial extent (radius = 500 m). The sum of linear elements length, percentage of urban areas and human population density calculated at the large extent (radius = 5 km) significantly improved the model. However, the predictive ability of these variables was less accurate. The model can be used by local authorities and land managers for modelling/predicting the hazards of invasion and elaborating a landscapelevel system of Solidago control.

“…E. graminifolia is most commonly recognised in Europe as Solidago graminifolia (L.) Elliot; however, based on anatomical and DNA studies (Semple et al 1981(Semple et al , 1984, the taxon should be classified to Euthamia Nutt. genus.…”

Section: Studied Speciesmentioning

confidence: 99%

“…In the native range, S. canadensis consists of diploid (2n = 18) and tetraploid plants (2n = 36), while S. altissima consists of hexaploid (2n = 54), triploid (2n = 27) and tetraploid (2n = 36) cytotypes (Semple et al 1981(Semple et al , 1984(Semple et al , 2015. Both taxa, S. canadensis var.…”

Section: Solidago Canadensismentioning

confidence: 99%

Historical contingency and spatial processes rather than ecological niche differentiation explain the distribution of invasive goldenrods (Solidago and Euthamia)

2016

Plant Ecol

The effectiveness of invasion depends on the interacting environmental factors and biology of the invader. The effects of these interactions are contingent on their contexts and difficult to predict. Among the most successful plant invaders in Europe are the goldenrods (Solidago and Euthamia genera). We assessed the roles of ecological niche differentiation and historical contingency on their distribution in Silesia (Central Europe, studied area approximately 32,000 km 2 ). The distributions of the two most common species (S. gigantea and S. altissima) were clumped, and the species dominated different areas. The distribution was unrelated to ecological niche differences but originates rather from the history of invasion and subsequent density-dependent spread; the species that was first introduced occupied available habitats and prevented the establishment of other species. Solidago canadensis was distributed randomly throughout the entire region and did not differ from S. altissima in its ecology. Euthamia graminifolia differed from the other goldenrods in habitat preferences and environmental requirements. Its distribution was strongly spatially structured, clumping around initial infestation sites. The extents of the differences resulting from ecological niche differentiation and the limitation of long-range dispersal are unclear. We argue that the under-representation of E. graminifolia in abandoned fields originates from the inhibition of establishment in habitats already occupied by other goldenrods. The results underline that the effect of historical contingency can be more prominent than ecological niche differentiation on invasive species distribution and invasion effectiveness.