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Of the six ovules in a capsule, one to three usually develop. In this capsule, one seed is normally developed, one is poorly developed and four are abortive. Microphoto: H.Å.
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The field garlic Allium oleraceum is reproducing by subterraneous bulbs, and above ground by bulbils and seed. Two chromosome numbers, tetraploid (2n = 32) and pentaploid (2n = 40) have been found in Finland and Sweden. The seed production was studied in some populations of A. oleraceum mainly in south Finland. The fruits mature only if visited by...
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Context 1
... fruit is a loculicid capsule with three loc- ules (Fig. 5). Each locule has two ovules (Hanelt 1992), of which only one normally develops into a seed (Fig. 6). Thus a ripe capsule usually contains 1-3 seeds. Of fruits studied by us from 11 localities in 2001, only one fruit from NBS (2n = 40) had 5 seeds and one fruit from Kökar Hamnö (2n = 40) had 4 seeds. All other fruits had 1-3 seeds. Either ovule ("right-hand" and "left-hand") in a locule can develop into a seed. The proportion of ...
Citations
... Bogdanović et al. (2009) andBrullo et al. (1994), respectively. Data for A. oleraceum were taken from various sources (stearn 1980, Åström & haeggström, 2004, Burešová 2012, karpavičienė 2012, aedo 2013 ...
Allium pseudotelmatum, a new species of A. sect. Codonoprasum, is described from the southern Dalmatia (Croatia). It is a late-summer flowering species with pentaploid (2n = 40) chromosome complement, occurring in synanthropic habitats (Citrus orchards with nutrient rich and fresh moist soil). Karyology, leaf anatomy, morphology, ecology, molecular (ITS) and taxonomic relationships with related species are examined for the species. It shows morphological relationships with the northern Dalmatian species A. telmatum from which it well differentiates for many morphological characters including the presence of aerial bulbils within the inflorescence, phenology, chromosome number and ecology. Confusion of A. pseudotelmatum with some specimens of A. oleraceum due to the presence of bulbils within the inflorescence is discussed.
... Although the higher CL G values found in A. vineale may be a result of the higher resolution of the molecular technique used (RAPD), which is more effective at detecting rarer genotypes than allozymes (Honnay and Jacquemyn 2008 ), we suggest an alternative explanation for the observed pattern. In contrast to the outcrossing A. oleraceum, whose seed set is limited (Åström and Haeggström 2004;), A. vineale is a self-compatible species (Richens 1947) that frequently produces substantial numbers of seeds (Ceplitis 2001). Honnay and Jacquemyn (2008) showed that clonal populations of self-incompatible species are less genotypically diverse than populations of selfcompatible species. ...
Clonal plants are, on average, considered to be as genetically diverse as nonclonal plants. However, the behaviour of clonal plants ranges between multiclonality and uniclonality, depending on environmental conditions and life history traits. Allozyme electrophoresis of band phenotypes was used to examine the genetic structure of 13 cytotype-uniform and 17 cytotype-mixed populations of polyploid Allium oleraceum (2n = 4x, 5x, 6x), a clonal bulbous geophyte that has been considered seed-sterile and completely reliant on vegetative reproduction through aerial bulbils and daughter bulbs. The genetic structure was dominated by low within-population variation whereas genetic differentiation was high among populations. Eighty-five distinct multilocus genotypes were found among 756 sampled individuals, but populations generally exhibited a low level of clonal diversity. Tetra- and pentaploids showed twofold higher total and within-population diversities, but also had more genetically differentiated populations in comparison with hexaploids. Tetraploids formed two separate groups in the cluster analysis, and this finding most likely suggests their different origin. Pentaploids were clustered in a separate cluster and frequently intermixed with tetra- and hexaploids sampled at cytotype-mixed sites. Such a pattern suggests gene flow between cytotypes. Most hexaploids were genetically similar and clustered separately from the other cytotypes, suggesting their similar origin and absence of gene flow to and from other cytotypes. Identical band phenotypes found in coexisting cytotypes within certain mixed-ploidy populations might indicate in situ neopolyploidization. Collectively, the pattern of genetic structure and diversity observed in A. oleraceum is typical of clonal plants with the dominance of vegetative offspring and scarce recruitment of sexual offspring. The low and spatially unstructured genetic variation observed in hexaploids, in contrast with higher and spatially structured genetic variation in tetra- and pentaploids, seems to be related to different levels of sexual fertility, ecological amplitude and colonization abilities of the cytotypes. It provides evidence for the existence of both primary and secondary contact zones of cytotypes in A. oleraceum.
... In Central Europe, only four cytotypes (2n = 3x, 4x, 5x, 6x) were found, although triploids are extremely rare (Šafá rová et al., 2011). Allium oleraceum reproduces sexually by seeds and asexually by aerial bulbils within the inflorescence and daughter bulbs underground (Åström and Haeggström, 2004; Krahulec and Duchoslav, 2010). However, for a long time, this species was considered to be seed sterile and to reproduce entirely asexually (Levan, 1933; Konvi9 cka, 1972). ...
... However, for a long time, this species was considered to be seed sterile and to reproduce entirely asexually (Levan, 1933; Konvi9 cka, 1972). Recent studies reported strong dominance of asexual reproduction by bulbils over flowers and variable but generally low sexual reproduction (Åström and Haeggström, 2004; Fialová and Duchoslav, 2014; Karpavi9 cien _ e, 2002; Karpavi9 cien _ e, 2012; Karpavi9 cienÅ1 and Karanauskaite, 2010). The existence of a range of cytotypes generates a question concerning the phenotypic differences between ploidy levels. ...
... phology of plants, phenotypic differences between cytotypes could be magnified (Richardson and Hanks, 2011). However, Karpavi9 cien _ e (2012) found differences in several morphological traits between tetra-and pentaploid A. oleraceum under common garden conditions, with pentaploids being higher, producing more bulbils and flowers than tetraploids. Åström and Haeggström (2004) tested the germination of seeds from tetra-and pentaploid plants and found that seeds from pentaploids germinated better in comparison to tetraploid ones. However, both studies were performed in northern Europe, where only two cytotypes (2n = 4x, 5x) are known, and they mostly occur in uniform cytotype populations. The situation in Cent ...
... Ramson blooming starts in the second half of April and finishes in the first half of May. The umbel-like inflorescence comprises 8–12 trimeric flowers, with a septal nectary between the base of the ovary and the stamens of the inner circle, characteristic for the Alliaceae family [6–9]. ...
Floral nectar volume and concentration of ramson (Allium ursinum L. ssp. ucrainicum) were investigated in three different habitats, including two types of sessile oak-hornbeam association on brown forest soil with clay illuviation and a silver lime-flowering ash rock forest association on rendzina. Daily nectar production ranged from 0.1 to 3.8 μL per flower with sugar concentrations of 25 to 50%. Mean nectar volumes and concentrations showed significant differences between freely exposed flowers and covered flowers, which had been isolated from flower visitors 24 h prior to nectar studies. Both the amount and quality of nectar were affected by microclimatic conditions and soil properties and varied between populations at different habitats. In the silver lime-flowering ash rock-forest association mean nectar volumes and concentrations were lower than in a typical sessile oak-hornbeam association on three occasions, the difference being significant in two cases. During full bloom, the date of sampling did not have a profound effect on either nectar volume or concentration.
... Растений, адаптированных к опылению складчатокрылыми осами, существует не так много. Помимо представителей рода Scrophularia веспидофильный опылительный синдром характерен для ряда видов орхидных рода дремлик -Epipactis Zinn (Orchidaceae) [36][37][38][39] и, как исключение, отмечен у одного из видов луков Allium oleraceum L. (Amaryllidaceae) [40]. Большинство дремликов, как и норичники, имеют красно-зеленую окраску околоцветника, привлекательную для ос и выделяют большое количество нектара 3 , доступного для короткохоботных насекомых. ...
The pollinators’ composition has been studied in the five species of figworts of the seven ones growing in Crimea: Scrophularia umbrosa, S. nodosa, S. scopolii, S. variegata subsp. rupestris and S. canina subsp. bicolor. Diplopterous wasps are the most effective and specialized pollinators in the majority of the studied species. Vespidophilous pollinating syndrome is typical for the species from the section Scrophularia (S. umbrosa, S. nodosa and S. scopolii) and syrphidophilous one – for S. canina subsp. bicolor (section Canina). The pollinators’ composition in S. variegata subsp. rupestris is known insufficiently. Morphometric parameters of the flowers in the studied species have been given and their relations with pollinators’ composition have been discussed. All species from the family Vespidae recorded on the figworts’ flowers with number of studied specimens have been listed. The hypothesis of wasp-pollination as the plesiomorphic character of the genus Scrophularia was speculated. On this view the species from the section Canina had changed their pollination syndrome to pollination mostly by hoverflies via the deficit of the diplopterous wasps as the effective pollinators in the open landscapes. The new key to identification of the species from the genus Scrophularia in the flora of Crimea has been proposed.
... This suggests limited gene flow between 4x and 6x cytotypes due to extremely rare production of flowers in hexaploids (Ohryzek, 2007) and rather indicates secondary contacts between cytotypes. Second, asexual reproduction via aerial bulbils and daughter bulbs strongly predominates over sexual reproduction in A. oleraceum (Duchoslav, 2000; Karpavičiene ˙, 2002; A ˚ ström and Haeggström, 2004; Ohryzek, 2007). Hence, even a single plant of one cytotype emerging within or invading a uniform population of another cytotype has the potential to persist as it can maintain itself and spread through asexual reproduction (Kao, 2007 ). ...
Despite extensive study of polyploidy, its origin, and ecogeographical differences between polyploids and their diploid progenitors, few studies have addressed ploidy-level structure and patterns of ecogeographical differentiation at various spatial scales using detailed sampling procedures. The pattern of coexistence of polyploids in the geophyte Allium oleraceum at the landscape and locality scale and their ecology were studied.
Flow cytometry and root-tip squashes were used to identify the ploidy level of 4347 plants from 325 populations sampled from the Czech Republic using a stratified random sampling procedure. Ecological differentiation among ploidy levels was tested by comparing sets of environmental variables recorded at each locality.
Across the entire sampling area, pentaploids (2n = 5x = 40) predominated, while hexaploids (2n = 6x = 48) and tetraploids (2n = 4x = 32) were less frequent. The distribution of tetra- and hexaploids was partially sympatric (in the eastern part) to parapatric (in the western part of the Czech Republic) whereas pentaploids were sympatric with other cytotypes. Plants of different ploidy levels were found to be ecologically differentiated and the ruderal character of cytotypes increased in the direction 4x --> 5x --> 6x with the largest realized niche differences between tetra- and hexaploids. Most populations contained only one ploidy level (77 %), 22 % had two (all possible combinations) and 1 % were composed of three ploidy levels. The majority of 4x + 5x and 5x + 6x mixed populations occurred in sympatry with uniform populations of the participating cytotypes in sites with ecologically heterogeneous or marginal environment, suggesting secondary contact between cytotypes. Some mixed 4x + 6x populations dominated by tetraploids being sympatric and intermixed with uniform 4x populations might represent primary zones of cytotype contact. Almost no mixed accessions were observed on the fine spatial scale in mixed populations.
The results provide evidence for adaptive differences among ploidy levels, which may contribute to their complex distribution pattern. The prevalence of asexual reproduction, limited dispersal and equilibrium-disrupting processes may support local coexistence of cytotypes.
... Allium oleraceum L. is a wide-ranging clonal bulbous geophyte, which occupies a multitude of different habitats in Europe (Duchoslav 2001a, Haeggström & Åström 2005, Karpavičiene ˙ 2008). It comprises triploid (2n = 3x = 24), tetraploid (2n = 4x = 32), pentaploid (2n = 5x= 40) and hexaploid (2n = 6x = 48) cytotypes (Krahulcová 2003, Åström & Haeggström 2004, Karpavičiene ˙ 2007). Recently the distribution and ecological differentiation among cytotypes in a sample of 325 populations in the Czech Republic were studied (Šafářová 2004Šafářová , Duchoslav et al. 2010). ...
... At the top of the scape of sexually mature plants there is a loose lax umbel with a few (0–30) hermaphrodite, protandrous flowers and many bulbils (10–60). Each flower can potentially produce six seeds (Stearn 1980), but seed production varies considerably and seedling establishment is low (Duchoslav 2000, Karpavičiene ˙ 2002, Åström & Haeggström 2004, Ohryzek 2007). ...
... Pilosella, show that pentaploids usually produce both euploid and aneuploid pollen grains ranging from 2x to 3x (). Because A. oleraceum pentaploids occasionally set well-developed seeds (Åström & Haeggström 2004, Ohryzek 2007) both euploids and aneuploids may be included within seed-sets (Fialová 1996). However, no adult aneuploid plants have been found in nature (Karpavičiene ˙ 2007, Duchoslav et al. 2010 ) suggesting they have a reduced fitness. ...
Despite the substantial knowledge of the variation in cytotypes at large spatial scales for many plants, little is known about the rates at which novel cytotypes arise or the frequencies and distributions of cytotypes at local spatial scales. The frequency distribution, local spatial structure, and role of habitat differentiation of tetra-, penta- and hexaploid cytotypes of the bulbous geophyte Allium oleraceum were assessed in 21 populations sampled in the Czech Republic. The ploidy levels determined by flow cytometry confirmed that there was a mixture consisting of two or three cytotypes (i.e. 4x+5x, 4x+6x, 5x+6x, 4x+5x+6x). In addition, mixtures of cytotypes were found at sites previously considered to be cytotype-homogeneous. At all sites previously found to contain a mixture of two cytotypes, no plants with the third ploidy level were found. Although the relative frequencies of cytotypes varied considerably both among and within populations, mixed populations consisting of tetra- and hexaploids were usually dominated by tetraploids. This suggests that there are secondary contacts among cytotypes but there is little gene flow among them except for the rare formation of hexaploids in tetraploid populations. Cytotypes were not randomly distributed over the study area but were spatially segregated at either 47.6% or 61.9% of the sites investigated, depending on the statistical test (Mantel test or average distance test) used. When the composition of habitats at each of the sites is taken into account, cytotypes were more frequently spatially segregated at sites with a heterogeneous environment than a homogeneous environment. This implies that the cytotypes are ecologically differentiated. The frequent co-occurrence of cytotypes, with or without significant spatial segregation, at many sites with heterogeneous or homogeneous environments, however, suggests that niche differentiation alone is probably ineffective in determining co-occurrence. It is supposed that the prevailing vegetative reproduction associated with local dispersal, a high population density of the species in a landscape, and non-equilibrial processes influencing the establishment and extinction of A. oleraceum populations can also support the local co-occurrence of cytotypes.
... This suggests limited gene flow between 4x and 6x cytotypes due to extremely rare production of flowers in hexaploids (Ohryzek, 2007) and rather indicates secondary contacts between cytotypes. Second, asexual reproduction via aerial bulbils and daughter bulbs strongly predominates over sexual reproduction in A. oleraceum (Duchoslav, 2000; Karpavičiene ˙, 2002; A ˚ ström and Haeggström, 2004; Ohryzek, 2007). Hence, even a single plant of one cytotype emerging within or invading a uniform population of another cytotype has the potential to persist as it can maintain itself and spread through asexual reproduction (Kao, 2007 ). ...
... Levan (1938) considered A. oleraceum to be an autopolyploid form of diploid Allium paniculatum that arose by somatic doubling of the chromosomes, although he did not rule out fusion of unreduced gametes as an alternative. ...
... The above-mentioned tetraploid and pentaploid chromosome numbers evidently prevail in this karyologically polymorphic species . Both cytotypes are reported from Austria (Tschermak-Woess 1947, Speta 1984, Wittmann 1984, Baranyi & Greilhuber 1999), Sweden (Lövkvist & Hultgård 1999), Finland (Åström & Haeggström 2004) and Russia (, Vakhtina & Kudryashova 1985 ). Three cytotypes , tetraploid, pentaploid and hexaploid (2n = 48), have been recorded in Switzerland (Wetschnig 1992) and the Czech Republic (Šafářová 2004Šafářová , Duchoslav et al. 2005). According to Duchoslav et al. (2005) pentaploids are most abundant and distributed evenly over the area of the Czech Republic, while hexaploids and tetraploids are less abundant and show partially vicarious patterns of distribution. ...
The somatic chromosome numbers of a total of 57 populations of five Allium species were studied in Lithuania. The chromosome numbers were: A. angulosum 2n = 16, A. lusitanicum 2n = 32, A. oleraceum 2n = 32 and 40, A. scorodoprasum 2n = 16 and 24, and A. vineale 2n = 32 and 24. Allium oleraceum, A. scorodoprasum and A. vineale showed ploidy differences both within and among populations.
... Kujala & Ulvinen (1964) noticed that specimens on the island of Kuorsalo in South Karelia were larger and had more flowers but fewer bulbils than specimens in the islands of Tammio and Ulko-Tammio farther out in the Gulf of Finland. This is most probably due to the fact that the plants on Kuorsalo were pentaploid (2n = 40), while on Tammio and Ulko-Tammio tetraploid (2n = 32; cf. Åström & Haeggström 2004). Only few studies of accompanying species are known to us. ...
The distribution of the field garlic, Allium oleraceum L., in Finland is presented according to herbaria voucher specimens, literature and field observations of the authors. The habitats of A. oleraceum, rock and dry meadows, mesic meadows, gardens and a few deciduous stands, are shortly described. The habitats are mostly influenced by man and domestic animals. The species is often found on iron age mounds, in ancient hilltop fortresses and in areas with medieval settlement, e.g. in connection with medieval castles and churches. A. oleraceum is moderately calciphilic as it is much more common in areas with calcareous bedrock or soil than in acid areas. The accompanying vascular plant flora is briefly presented.
