PAFlogo_small1.jpg (7865 bytes) Home ] PAF News ] Checklist ] PAF Feedback ] PAF Search Page ]

General aspects ] Case studies ] Delimitation and subdivision ] Information management ] Reports from taxonomic workshops ]

Back ] Up ] Next ]

ARE THERE TOO MANY SPECIES AND SUBSPECIES IN THE PAPAVER RADICATUM COMPLIE?

Heidi Solstad, Reidar Elven & Inger Nordal

Introduction

Material and methods

Results

Discussion

Acknowledgements

References

Nordic authors (e.g. Knaben 1959a, 1959b, Elven in Lid & Lid 1994, Elven & Elvebakk 1996, Solstad 1998, Nilsson in press) currently accept four species of Papaver sect. Scapiflora Reichenb. (Sect. Maconella Spach.) within the Flora Nordica area: P. dahlianum Nordh. (Fig. 1a) in Svalbard, Bear Island and N Norway, P. laestadianum (Nordh.) Nordh. (Fig. 1b) as a local endemic in N Scandinavia, P. lapponicum (Tolm.) Nordh. (Fig. 1c) with 1-2 subspecies in N Norway, and P. radicatum Rottb. (Fig. 1d) as a North Atlantic endemic, with about 10 subspecies in S and N Scandinavia and 3-4 subspecies in Iceland, one of which also reaching the Faeroes. These authors considered P. radicatum as a geographically restricted species, not reaching westwards to Greenland and not found east of the Scandinavian mountain range, P. dahlianum as a fairly widely distributed high-arctic amphi-Atlantic species, and P. lapponicum as a nearly circumpolar species.

Looking at Russian treatises (e.g. Tolmachev 1975, see also Petrovsky 1999), three species of arctic-alpine poppies are reported more or less throughout the Russian and West Siberian Arctic eastwards to the Beringian area: Papaver lapponicum (Tolm.) Nordh. in three major races, subsp. lapponicum in Kola peninsula, subsp. jugoricum (Tolm.) Gudshnikov in NE Russia, Novaya Zemlya and West Siberia, and subsp. orientale Tolm. further east in Siberia. P. polare (Tolm.) Perfil. in Franz Joseph Land, Novaya Zemlya and N Siberia, and P. radicatum Rottb. s. lat. here and there throughout Siberia (but not in the European part). In the Beringian area, several more species are accepted on both sides of the Bering Strait.

On the American side east of the Beringian area, different names are used in some cases, but probably representing the same taxa (Kiger & Murray 1997): Papaver lapponicum subsp. occidentale (Lundstr.) Knaben throughout most of arctic N America and Greenland, P. radicatum subsp. radicatum widespread in the same area, P. radicatum subsp. polare Tolm. in N and NE Canada and Greenland. The most recent surveys of parts of Greenland accept only a widely defined P. radicatum in several 'types' (Feilberg 1984, Bay 1992, Fredskild 1996).

These treatments are mutually incompatible in several aspects. (1) Papaver radicatum Rottb. cannot at the same time be an endemic of Iceland and Scandinavia and widely distributed throughout Greenland, Canada, Alaska and Russia. (2) The majority of the Greenland-American materials cannot be both a more or less homogeneous species (P. lapponicum in the sense of Knaben 1959a, 1959b; P. radicatum in the sense of current Danish authors) and consist of two species (P. lapponicum and P. radicatum in the sense of Kiger & Murray 1997). (3) It is improbable that the high arctic NE American and NW Russian/Siberian plants are P. polare (or P. radicatum subsp. polare), whereas the high arctic Greenland plants are P. radicatum, and the high arctic Svalbard plants are P. dahlianum, at least as long as the plants in NE Greenland, Svalbard and Franz Joseph Land are morphologically inseparable. The focus here will be on the variation in the N Atlantic area, including Greenland and Svalbard.

These arctic-alpine Papaver taxa have been a taxonomic headache since the end of the 19th century when it was recognised that P. nudicaule L. (Linnaeus 1753) could not include all variation, and when P. radicatum Rottb. (Rottbøll 1770) was rediscovered as a valid name for at least parts of the arctic variation. There are several phases since then in the development of the species concept in the group. Five important crossroad periods and the main participants are:

(a) 1894-1923, when Murbeck (1894) and Lundström (1914, 1923) interpreted much of the N Atlantic and N Russian variation as caused by hybridization between Papaver nudicaule and P. radicatum. This interpretation was mainly initiated by observations of hybrids in botanical gardens, but did not take fully into account that the proposed hybrids almost always occurred in areas where their putative parents were absent (today).

(b) 1923-1932, when Tolmachev (1923, 1927) and Nordhagen (1932) refuted the hybrid hypothesis and described the variation they found as several species, especially Papaver dahlianum (Nordhagen 1932), P. lapponicum (Tolmachev 1923 as subspecies of P. radicatum, Nordhagen 1932 as species) and P. polare (Tolmachev 1923 as subspecies of P. radicatum, Perfiljev 1936 as species), partly also with subspecies for local and regional races. Those authors initiated a school accepting comparatively wide species with regional and local variation described as subspecies, in the sense of geographical races.

(c) 1938-1959, when Horn (1938), Holmen (1952), Löve (1955) and Knaben (1958, 1959a, 1959b) discovered several ploidy levels in the group. This 'Nordic' reliance on ploidy differences as criteria of species resulted in certain taxonomic changes and in evolutionary interpretations. During this phase, Papaver lapponicum (octoploid, 2n=56) was considered to be clearly specific distinct from P. radicatum and P. dahlianum (both decaploids, 2n=70), and P. laestadianum was recognized as a species distinct from P. radicatum because of its octoploidy.

(d) 1945-present, when the ploidy differences found made the typification of Papaver radicatum crucial for the interpretation of naming and for understanding the geographical distribution of taxa. The typification debate concerned, firstly, the question of the nomenclatorial type of P. radicatum, and secondly, whether this 'type' - which happens to be a drawing (Fig. 2) - was made from material originating in Greenland or in Iceland. If the type was from Iceland, it most probably is a decaploid, and if from Greenland an octoploid. A typification based on the decaploid would, if the difference between the ploidy levels is recognised at the species level, reserve the name 'P. radicatum' for the geographically restricted North Atlantic decaploid whereas the name 'P. lapponicum' would be the one to apply to the widely distributed octoploid. Hultén (1945), followed by Löve (1955, 1962a, 1962b), argued for a Greenlandic typification, but this was disputed by Knaben (1958) and Knaben & Hylander (1970). Nilsson (in press), based on the arguments of Knaben (1958) and Knaben & Hylander (1970), argues for and will propose a formalisation of an Icelandic (i.e. decaploid) typification of P. radicatum, a view we fully agree with.

(e) 1974-present, a synoptical phase with attempts of world-wide (Rändel 1974) and regional surveys (Tolmachev 1975 - Russia; Kadereit 1993 - Europa; Kiger & Murray 1997 - N America; Nilsson in press - the Nordic area). In this phase, information from several sources is included. These attempts differ significantly from each other, partly because of different data sets utilized, partly (still) because of different interpretations of the types of P. radicatum and P. dahlianum. Kiger & Murray (1997) separate P. lapponicum form P. radicatum on other criteria than done by Nordic authors. Rändel (1974) and Kadereit (1993) include P. dahlianum as a subspecies of P. radicatum, probably because of its decaploid status, whereas they keep P. laestadianum as a separate species. This approach is not followed by any Nordic or Russian authors. Kiger & Murray (1997) doubt the identity between P. dahlianum and P. polare, Tolmachev (1975) probably, too, as he keep P. polare as species, whereas Nilsson (in press) and other Nordic authors regard P. polare as a synonym of P. dahlianum.

At present, there is therefore no agreement about taxa or delimitations, in spite of this being one of the most thoroughly investigated of all groups of arctic plants. This may be a warning when going into other complicated arctic polyploid complexes, i.e. Draba, Oxytropis or Poa. The first major experimental investigations of Papaver were undertaken in the 1950ies (Knaben 1959a, 1959b), utilizing morphology, cytology and crossing experiments, and with univariate statistics, before the introduction of more sophisticated statistical analysis and especially before the use of genetic markers. Later investigations have mainly had as aims to test the findings of Knaben, by multivariate morphometry (Selin & Prentice 1988, Selin 1999) and by chemotaxonomy (Folkestad et al. 1988). A study applying genetic markers was therefore due, especially as Knaben (1959a, 1959b) proposed a hybrid origin of the decaploids P. radicatum and P. dahlianum from the octoploid P. lapponicum and the presumed diploids P. alpinum and P. nudicaule, respectively. Later studies have, however, shown that P. nudicaule in the sense of Knaben probably is P. croceum Ledeb., whereas the true P. nudicaule is a polyploid.

The aims of the present study are:

  • To analyse the genetic variation within and among subspecies of P. radicatum in the Nordic area by isoenzymes and RAPD,
  • To report some results on reproduction and demography for P. radicatum,
  • To analyse the genetic variation between P. radicatum and other Scapiflora taxa - P. alpinum, P. dahlianum, P. laestadianum, P. lapponicum and P. 'nudicaule' by isoenzymes,
  • To compare genetic variation between P. dahlianum in Svalbard and in N Norway by isoenzymes to test their identity, questioned by Kiger & Murray (1997),
  • To test the hypothesis of allopolyploid origins of the decaploids P. dahlianum and P. radicatum from taxa at diploid and octoploid levels,
  • To indicate taxonomic and phytogeographical implications of these results.

Other results from this study were presented by Nordal et al. (1997), Solstad et al. (1997), and Solstad (1998). A more detailed version is under preparation (Solstad et al. in prep.).

button-arrow-back.gif (860 bytes) Contents


Fig. 1.

Fig.1.jpg (56843 bytes)

Drawings of the four North Atlantic species of Papaver sect. Scapiflora: a. P. dahlianum Nordh., b. P. laestadianum (Nordh.) Nordh., c. P. lapponicum (Tolm.) Nordh. and d P. radicatum Rottb. Drawings by Miranda Bødtker.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Fig. 2.

Fig.2.jpg (85692 bytes)

The plate representing the type of Papaver radicatum, from Rottb?ll (1770).

Material and methods

A full set of investigations (isoenzymes, RAPD, demography, habitat choice) were undertaken on materials from 20 populations of the six described South Norwegian subspecies of P. radicatum. Offspring from a single plant of an Icelandic subspecies was also included in investigations of both types of genetical markers. The reproductive system was investigated in two South Norwegian subspecies. Isoenzyme variaton was also investigated in one population each of P. alpinum subsp. sendtnerii (Austria), P. dahlianum (Svalbard), P. laestadianum (North Norway), P. lapponicum (North Norway) and P. 'nudicaule' (garden material, probably P. croceum Ledeb.).

button-arrow-back.gif (860 bytes) Contents


Results

Extremely little variation in the genetic markers was found within and among the South Norwegian and Icelandic populations/subspecies of Papaver radicatum, both as to isoenzymes (Fig. 3a) and RAPD-markers (Fig. 3b). The small variation found was within populations and subspecies, not among them: One deviant isoenzyme multilocus phenotype was found in one population of subsp. gjaerevollii (in the South Norwegian Trollheimen mountains) and another deviant phenotype in some of the plants of the Icelandic subsp. steindorssonianum.

The plants in the two populations (of subspp. oeksendalense and ovatilobum) investigated for reproductive system proved to be mainly autogamous with autodeposition, but with a possibility of outcrossing. Segregation in the offspring from the single Icelandic plant studied also indicates that some outcrossing takes place. These plants can therefore be classified as mixed maters, but probably with self-pollination as the rule.

Demographically, there seems to be rapid turnover of generations in dynamic populations. Populations with many or predominantly old plants occur, but they are few. In habitat choice, the S Norwegian subspecies do not seem to differ; apparent differences may be ascribed to presence or absence of suitable habitats as scree slopes, riverbanks, road verges, alpine slopes or moraine ridges in the areas where they occur. The two major habitat types are calcareous screes and river banks. Suitable river banks are lacking in the areas where subspp. gjarevollii, oeksendalense and relictum are found. Calcareous screes are rare in the area of subsp. intermedium whereas riverbanks are common. In areas where all suitable habitats are abundant, as in the Dovrefjell area with subsp. ovatilobum, P. radicatum occurs in all.

In a comparison between Papaver radicatum and other Scapiflora species, comparatively little variation of isoenzymes was found. The first axis in a PCO analysis (Fig. 3a) based on the isoenzyme multilocus phenotypes separated between P. dahlianum and the remaining taxa. The second axis separated between P. nudicaule and the majority of P. alpinum at one end and the group of P. radicatum, P. laestadianum, P. lapponicum and some few P. alpinum plants at the other end. The isoenzyme multilocus phenotype of Papaver laestadianum was identical to the majority phenotype in P. radicatum. The deviating multilocus phenotype in P. radicatum subsp. steindorssonianum was identical with one of the four phenotypes found in P. alpinum, and closest to the deviating multilocus phenotype in subsp. gjaerevollii.

Two multilocus phenotypes were found in P. dahlianum from Svalbard (one population Fig. 3a). The isozyme phenotype found in one of the few populations in N Norway, close to the type locality of the species, was identical to one of the Svalbard phenotypes.

No direct evidence of additive patterns in isoenzymes was found between P. alpinum (2x) / P. lapponicum (8x) and P. radicatum (10x), or between P. 'nudicaule' (=P. croceum) (probably 2x) / P. lapponicum (8x) and P. dahlianum (10x).

button-arrow-back.gif (860 bytes) Contents


Fig. 3

Fig3.jpg (32446 bytes)

a. A PCO ordination of the results of analyses of isoenzymes in Papaver radicatum, P. alpinum P. lapponicum and P. laestadianum. The calculations are made on the basis of absence (0) or presence (1) of eight homomeric enzyme bands: Gpi-2a, Gpi-2c, Gpi-2d, Tpi-b, Mdh-1a, Mdh-1d, Mdh-1e, and Pgd-2b. b. An UPGMA-dendrogram based on the results RAPD analyses of S Norwegian and Icelandic Papaver radicatum populations. The calculations are made on the basis of absence (0) and presence (1) of six polymorphic RAPD markers. In both cases are Euclidean distance used as dissimilarity measure. Abbreviations: Alp=P. alpinum ssp. sendtnerii, Dhl=P. dahlianum, Lae= P. laestadianum, Lap=P. lapponicum, Nud=P. nudicaule, Rad=P. radicatum – including the 7 analysed subspecies: Rgj= ssp. gjaerevollii, Rgr= ssp. groevudalense, Rin= ssp. intermedium, Roe=ssp. oeksendalense, Rov=ssp. ovatilobum, Rre=ssp. relictum, Rst=ssp. steindorssonianum

Discussion

The species and subspecies of the Scapiflora Papavers, including P. radicatum, P. dahlianum, P. laestadianum and P. lapponicum, have been central in the discussion of survival and speciation of the North European mountain flora during the Weichselian or throughout all the Pleistocene glaciations see e.g. Nordhagen (1936, 1963), Knaben (1959a, 1959b), Gjærevoll (1963), Nordal (1985, 1987), and Dahl (1989). Some geographically structured morphological differences are found within both P. radicatum (see, e.g., Selin 1999) and the other species, but mainly in quantitative characters and mainly in combinations of them.

The scant variation in genetical markers among populations of P. radicatum and its subspecies does not support the recognition of subspecies.

It is interesting to note that seeds from one population of the diploid P. alpinum subsp. sendtneri, are much more genetically (enzymatically) variable than the entire body of material analysed for P. radicatum-laestadianum-lapponicum complex. The reason may well be that P. alpinum is outcrossing whereas the complex of P. radicatum-laestadianum-lapponicum is predominantly inbreeding.

Morphologic differences between North Norwegian and Svalbard plants of Papaver dahlianum were the reason for Kiger & Murray (1997) to doubt the validity of the name P. dahlianum for the arctic poppies. The morphologic differences are slight and may easily have been caused by genetic drift in postglacial time, in these small, mainly selfing, semi-isolated and fluctuating populations on the mainland. The enzymatic identity between P. dahlianum from N Norway and one of the multilocus phenotypes from Svalbard supports the view that these plants should be placed in the same species. By implication, P. dahlianum should then, due to priority, be the accepted name for this high arctic species both in the Nordic area, Russia, Greenland, and Canada, replacing the younger name P. polare. Papaver dahlianum is unambiguously typified (O) whereas Tolmachev (1923) included sites also of P. lapponicum in his protologue (and determinations) of P. polare. A possible type of P. polare designed by Tolmachev (in LE) has been lost. And the name was lectotypified by Egorova (1998) on a material from Svalbard. This typification further supports the reduction of P. polare to synonymy of P. dahlianum.

The relationship of Papaver dahlianum to other species within the genus is, however, still unsolved. Knaben's hybrid origin hypothesis is not supported by the presented results. Papaver dahlianum seems to represent a distinct species, at least in the N Atlantic area, much less related to the others (P. laestadianum, P. lapponicum, P. radicatum) than those are among themselves. It probably has an evolutionary history different from the other North European taxa, and we should perhaps look towards the Beringian area where, P. gorodkovii Tolm. & Petrovsky appears to be a closer relative.

The C European diploid Papaver alpinum may have furnished genomes to the North European polyploid complex, and an allopolyploid origin of P. radicatum from P. alpinum and P. lapponicum can not be excluded by our results. It is, however, not the simplest hypothesis. A simpler alternative might be auto-polyploidization from P. alpinum stock (or a similar stock) to reach both the octoploid (P. lapponicum and P. laestadianum) and the decaploid (P. radicatum) levels. The very low genetic diversity in the group of P. radicatum-laestadianum-lapponicum argues against an allopolyploid origin. It was striking that most isozymes displayed fewer bands when compared to other arctic polyploids of allopolyploid origin (see Solstad et al. in prep.).

Papaver laestadianum is so similar to P. radicatum isozymatically that it may differ from P. radicatum only in having one genome in single dose that P. radicatum has in double dose. Maintenance of P. laestadianum as a separate species, even if octoploid, is therefore problematic. The documented morphological differences are also small, not larger than the morphological differences between the recognized subspecies of P. radicatum. One of the very few Scandinavian mountain range endemics might therefore belong to the P. radicatum species which is not an endemic.

The implications are clear: there are much smaller differences genetically among many of the N Atlantic Scapiflora poppies than previously assumed. The differences between P. radicatum and P. lapponicum might be so small that they might be included within one single species.

The analyses of the N Atlantic Papaver Sect. Scapiflora may also throw some light on the problems of the 'Species Concept in the Arctic'. It is a classical case of different results reached in different 'political' areas, e.g. the Nordic countries, Russia, America and Greenland. It has often been assumed that the Russians, following the tradition of Komarov (1934 and later), have applied a more narrow species concept than most Europeans and Americans. In the present case, the major splitters seem to have been most active in the N Atlantic area. If we consider both species and subspecies, about as many taxa of Papaver Sect. Scapiflora have been described within the very small variation found around the N Atlantic as within the much more impressive variation found in the Beringian area.

The investigations should now be extended to includ the taxa recognized as P. lapponicum and P. radicatum in Greenland and North America, the Russian taxa described within P. lapponicum, and to possible progenitors of the high-ploid arctic complex(es), if extant in the Beringian, Cordilleran and C and E Asian areas.

button-arrow-back.gif (860 bytes) Contents


Acknowledgements

We have had inspiring discussions with Dr. D.F. Murray, Dr. O. Nilsson and Dr. V.V. Petrovsky on taxonomical questions. We thank for all the comments, and a special thank to Dr. D.F. Murray for refereeing the manuscript.

button-arrow-back.gif (860 bytes) Contents


References

Bay, C. 1992. A phytogeographical study of the vascular plants of northern Greenland - north of 74 º northern latitude. – Meddel. Gronland, Bioscience 36.

Dahl, E. 1989. Nunatakk-teorien II. - Endemismeproblemet. – Blyttia 47: 163-172.

Egorova T.V. 1998. Genus Papaver L. (Papaveraceae) in the flora Eastern Europe. [Rod Papaver L. (Papaveraceae) vo flore Vostochnoy   Evropy]. – Nov. sist. vysshykh rast. 31: 90-118 (in Russian).

Elven, R. & Elvebakk, A. 1996. Part 1. Vascular plants. – In: Elvebakk, A. & Prestrud, P. (Eds) A catalogue of Svalbard plants, fungi, algae, and cyanobacteria. - Norsk Polarinst. Skr. 198: 9-55.

Feilberg, J. 1984. A phytogeographical study of South Greenland. – Meddel. Grønland, Bioscience 15.

Folkestad, K., Høiland, K., Paulsen, B.C. & Malterud, K.E. 1988. Alkaloid chemotaxonomy of Nordic Papaver sect. Scapiflora (Papaveraceae). – Nord. J. Bot. 8: 139-146.

Fredskild, B. 1996. A phytogeographical study of the vascular plants of West Greenland (62 º20' - 74º 00'). Meddel. Grønland, Bioscience 45.

Gjærevoll, O. 1963. Survival of plants on nunataks in Norway during the Pleistocene glaciation. – In: Löve, Á. & Löve, D. (Eds) North Atlantic biota and their history. Pergamon Press, Oxford. pp. 261-283

Holmen, K. 1952. Cytological studies in the flora of Peary Land, North Greenland. - Medd. Grønl. 128: 1-40.

Horn, K. 1938. Chromosome numbers in Scandinavian Papaver species. - Avh. Norske Vidensk. Akad. Oslo., I. Mat.-Naturv. Kl. 1938, 5.

Hultén, E. 1945. Flora of Alaska and Yukon. V. - Lunds Univ. Arsskr., N.F., Avd. 2, 41, 1: 799.978.

Kadereit, J.W. 1993. Papaver L. – In: Tutin, T.G. et al. (Eds) Flora Europaea 1, 2. ed. Cambridge Univ. Press, Cambridge. pp. 297-301

Kiger, R.W. & Murray, D.F. 1997. Papaver L., – In: Morin, N.R. et al.(Eds) Flora of North America north of Mexico. 3. Magnoliophyta: Magnoliidae and Hamamelidae. Oxford Univ. Press, New York. pp. 323-333

Knaben, G. 1958. Papaver-studier, med et forsvar for P. radicatum Rottb. som en islandsk-skandinavisk art. – Blyttia 16: 61-79.

Knaben, G. 1959a. On the evolution of the Radicatum-group of the Scapiflora papavers as studied in 70 and 56 chromosome species. A. Cytotaxonomical aspects. – Opera Bot. 2, 3: 1-74.

Knaben, G. 1959b. On the evolution of the Radicatum-group of the Scapiflora papavers as studied in 70 and 56 chromosome species. B. Experimental studies. – Opera Bot. 3, 3: 1-96.

Knaben, G. & Hylander, N. 1970. On the typification of Papaver radicatum Rottb. and its nomenclatural consequences. - Bot. Not. 123: 338-345.

Komarov, V.L. (Ed) 1934-1960. Flora of USSR [Flora SSSR]. - Izdatelstvo AN SSSR, Leningrad (in Russian).

Lid, J. & Lid, D.T. 1994. Norsk Flora, 6. ed. by R. Elven. Det Norske Samlaget, Oslo.

Linnaeus, C. 1753. Species plantarum. - Holmiae.

Löve, Á. 1955. Cytotaxonomical remarks on the Icelandic Papaver. - Nytt Mag. Bot. 4: 5-18.

Löve, Á. 1962a. Typification of Papaver radicatum - a nomenclatural detective story. - Bot. Not. 115: 113-136.

Löve, Á. 1962b. Nomenclature of North Atlantic papavers. - Taxon 11: 132-138.

Lundström, E. 1914. Beobachtungen und Studien bei den in den Jahren 1912-13 ausgeführten Pflanzenbestimmungen im Botanischen Garten Bergielund (Hortus Botanicus Bergianus). - Acta Hort. Berg. 5, 3: 1-121.

Lundström, E. 1923. Über Papaver nudicaule L. und P. radicatum Rottb. in Fennoskandia und Arktis sowie uber einige mit P. nudicaule verwandte Arten. - Acta Hort. Berg. 7: 403-430.

Murbeck, S. 1894. Neue oder wenig bekannte Hybriden in dem Botanischen Garten Bergielund (Hortus Botanicus Bergianus). - Acta Hort. Berg. 2, 5: 1-24.

Nilsson, Ö. (in press). Papaver sect. Scapiflora, – In: Jonsell, B. (Ed) Flora Nordica 2.

Nordal, I. 1985. Overvintringsteori og evolusjonshastighet. – Blyttia 43: 33-41.

Nordal, I. 1987. Tabula rasa after all? Botanical evidence for ice-free refugia in Scandinavia reviewed. – J. Biogeogr. 14: 377-388.

Nordal, I., Hestmark, G. & Solstad, H. 1997. Reproductive biology and demography of Papaver radicatum - A key species in Nordic plant geography. – Opera Bot. 132: 77-87.

Nordhagen, R. 1932. Studien über die skandinavischen Rassen des Papaver radicatum Rottb. sowie einigie mit denselben verwechselte neue Arten. – Bergens Mus. Årb. 1931, Naturv. R. 2.

Nordhagen, R. 1936. Skandinavias fjellflora og dens relasjoner til den siste istid. - Nord. Naturf.-mötet Helsingfors 1936: 93-124.

Nordhagen, R. 1963. Recent discoveries in the South Norwegian flora and their significance for the understanding of the history of the Scandinavian mountain flora during and after the last glaciation. – In: Löve, Á. & Löve, D. (Eds) North Atlantic biota and their history. - Pergamon Press, Oxford. pp. 242-260.

Perfiljev, I.A. 1934-1936. Flora of the Northern Land [Flora Severnogo Kraya].  - Sevkraigiz,Arkhangelsk,1: 159 pp; 2-3: 393 pp. (in Russian).

Petrovsky, V.V. 1999. The problem of the species width in poppies of Russian Arctic. – Det Norske Videnskaps - Akademi. I. Mat. Naturv. Klasse, Skrifter, Ny serie 38: 243-259.

Rändel, U. 1974. Beiträge zur Kenntnis der Sippenstruktur der Gattung Papaver L. Sectio Scapiflora Reichenb. (Papaveraceae). – Feddes Repert. 84: 655-732.

Rottbøll, C.F. 1770. Afhandling om en Deel enten ganske nye eller vel forhen bekiendte, men dog for os rare Planter, som i Island og Grønland ere fundne, tilligemed en kort Indledning om Urtelærens Tilstand i Dannemark. – Skr. Kiöbenhavnske Selsk. L?rd. Elsk. 10: 393-462.

Selin, E. 1999. Morphometric differentiation in Papaver radicatum (Papaveraceae). Geographic pattern and significance for refugial survival theory. – Acta Univ. Upsal., Compr. Summ. Uppsala Diss. Fac. Sci. Techn. 444.

Selin, E. & Prentice, H.C. 1988. Morphometric analysis of disjunct Papaver radicatum (Papaveraceae) populations in southern Norway. – Pl. Syst. Evol. 159: 237-247.

Solstad, H. 1998. Genetical and ecological variation in S Norwegian Papaver radicatum Rottb. Comparisons with related species, and implications for taxonomy and phytogeography. – Cand. scient. thesis, Univ. of Oslo.

Solstad, H., Elven, R. & Stabbetorp, O. 1997. Habitatvalg og demografi hos de sørnorske fjellvalmuene (Papaver radicatum). – NTNU Vitensk. Mus. Rapp. Bot. Ser. 1997-1: 67-87.

Tolmachev, A. 1923. On the european races of Papaver radicatum Rottb. [O evropeyskikh rasakh Papaver radicatum Rottb.] – Not. Syst. Herb. Horti Bot. Petrop. 4: 81-90.

Tolmachev, A. 1927. Über die Formen von Papaver radicatum Rottb. und ihre Verbreitung in Skandinavien. – Sv. Bot. Tidskr. 21: 73-83.

Tolmatchev, A.I. 1975. Genus Papaver L. [ Rod Papaver L.]. – In: Tolmatchev, A.I. (Ed) Arctic Flora USSR. VII. Papaveraceae-Cruciferae. Nauka, Moskva-Leningrad. pp. 7-32 (in Russian).

button-arrow-back.gif (860 bytes) Contents


 
Send mail to webmaster@binran.ru with questions or comments about PAF web site.
Copyright 2000-2005 Panarctic Flora Project
Last modified: 04.02.2005