A cytotaxonomic survey of the Pteridophyta of Australia

2002 ◽  
Vol 15 (6) ◽  
pp. 839 ◽  
Author(s):  
Mary D. Tindale ◽  
S. K. Roy

A cytotaxonomic survey of the ferns and fern allies of Australia (including Lord Howe Island) is presented. Five-hundred-and-twenty-six chromosome counts of 268 Australian species, subspecies, varieties, variants and hybrids are recorded, only a small number having been previously investigated by other botanists on Australian material. Diploids represent c. 62% of the counts on species and c. 38% on polyploids, the latter ranging principally from triploids to a single decaploid and dodecaploid (but no heptaploids). More than one ploidy level has been reported in 19 taxa (almost 8% of taxa). Counts of 10x for Asplenium aethiopicum and 12x for A.�flabellifolium are the highest definite ploidy levels for the Australian pteridophyte flora. Chromosome counts for 29 families and 89 genera are cited. Only diploids were reported for Osmundaceae and Cyatheaceae, but only polyploids for the Psilotaceae, Vittariaceae and Ophioglossaceae. An analysis is given of the levels of ploidy in 248 taxa, excluding the Lycopodiaceae and Hymenophyllaceae. The percentages of diploids and polyploids in Australian species are compared with those of nearby countries. Many species reported on here have never been cytologically investigated before, while others have not been studied previously on Australian material. The following genera have been examined cytologically for the first time: Coveniella Tindale, n = 41; Paraceterach (F.Muell.) Copel., n = 29; 'Oenotrichia Copel.', 2n = 82 (2x); Revwattsia (Watts) D.L.Jones, 2n = c. 328 (8x); and Pteridoblechnum Hennipman (2n = 54). The phylogeny of the genera is discussed in the light of these findings. Certain families such as the Adiantaceae, Cyatheaceae, Hymenophyllaceae, Lindsaeaceae and Marsileaceae were given special attention by collecting as much living material as possible. A number of species-complexes has been found and further chromosome counts added to intercontinental species complexes. The Döpp-Manton and Braithwaite forms of reproductive apomixis have been reported amongst some genera. Endemism, hybridity and apogamy amongst Australian pteridophytes are discussed, as well as homosporous and heterosporous species. The new combination Phymatosorus membranifolius (R.Br.) Tindale is made.

2008 ◽  
Vol 8 (2) ◽  
pp. 247-250
Author(s):  
Cristina de Oliveira Dias ◽  
Guilherme Fulgêncio de Medeiros ◽  
Sérgio Luiz Costa Bonecker

During a series of zooplankton surveys carried out during 1984, off the south coast of the state of Rio Grande do Norte, Brazil, several species of monstrilloids were present in the samples. A total of 50 individuals of monstrilloid copepods were collected. These belong to four species (Monstrilla brasiliensis Suárez-Morales & Dias, Cymbasoma cf. longispinosum, Cymbasoma cf. rigidum, and Cymbasoma gracilis Gurney). The taxonomic complexes formed by the species C. cf. longispinosum and C. cf. rigidum in Brazilian waters are discussed. The lengths of the specimens are provided in order to contribute to studies and revisions of the specimens belonging to these species-complexes. The species Monstrilla brasiliensis is recorded for the first time in the Rio Grande do Norte coastal region, thus expanding its geographical range in the Brazilian northeastern coast. The results presented herein increase to four the number of species of Monstrilloida known from off Rio Grande do Norte state.


Caryologia ◽  
2021 ◽  
Vol 74 (1) ◽  
pp. 53-61
Author(s):  
Maryam Hasaninejad ◽  
Ziba Jamzad ◽  
Saeid Afsharzadeh ◽  
HojJatollah Saeidi

In this survey, the chromosome counts of eight Nepeta L. species were investigated and the karyotypic diversity among these species was studied. The examined species belong to N. cephalotes Boiss. species group, namely N. eremokosmos Rech.f., N. gloeocephala Rech. f., cephalotes Boiss., N. pungens (Bunge) Benth., N. ispahanica Boiss., N. mahanensis Jamzad & Simonds, N. hormozganica Jamzad and N. denudata Benth. collected from different habitats in Iran. The ploidy levels, karyotype formula, chromosome length range, total karyotype length, several karyotype asymmetries values and Stebbins classification were determined in this study. Results showed the same chromosome number, 2n = 2x= 18 for all studied species. The basic chromosome number for the above mentioned species are x = 9. Also, the smallest chromosome length is 1.02 μm in N. mahanensis. The largest chromosome length is 2.3 μm in N. ispahanica. The chromosomes of species were metacentric or submetacentric. According to the Stebbins classification, these species were located into three classes 1A, 2A and 3A. The chromosome numbers for six of studied species are reported here for the first time.


Brunonia ◽  
1981 ◽  
Vol 4 (2) ◽  
pp. 309
Author(s):  
HP Nooteboom

A complete account with full descriptions is given of the Australian species of Symplocos. Keys to all accepted taxa are provided. The following new taxa are described: Symplocos hylandii Nooteboom and S. cochinchinensis vars glaberrima Nooteboom and pilosiuscula Nooteboom. A new combination is S. cochinchinensis var. candelabrum (Brand) Nooteboom for a taxon endemic to Lord Howe Island.


Genes ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 906
Author(s):  
Gloria Martínez-Sagarra ◽  
Sílvia Castro ◽  
Lucie Mota ◽  
João Loureiro ◽  
Juan A. Devesa

Polyploidy has played an important evolutionary role in the genus Festuca (Poaceae), and several ploidy levels (ranging from 2n = 2x = 14 to 2n = 12x = 84) have been detected to date. This study aimed to estimate the genome size and ploidy level of two subspecies belonging to the F. yvesii polyploid complex by flow cytometry and chromosome counting. The phenotypic variation of the cytotypes was also explored, based on herbarium material. The genome size of F. yvesii subsp. lagascae has been estimated for the first time. Nuclear 2C DNA content of F. yvesii subsp. summilusitana ranged from 21.44 to 31.91 pg, while that of F. yvesii subsp. lagascae was from 13.60 to 22.31 pg. We report the highest ploidy level detected for Festuca (2n = 14x = 98) and previously unknown cytotypes. A positive correlation between holoploid genome size and chromosome number counts shown herein was confirmed. The morphometric approach showed a slight trend towards an increase in the size of some organs consistent with the variation in the ploidy level. Differences in characters were usually significant only among the most extreme cytotypes of each subspecies, but, even in this case, the high overlapping ranges prevent their distinction.


1984 ◽  
Vol 62 (6) ◽  
pp. 1279-1282 ◽  
Author(s):  
Gary H. Morton

The Solidago gigantea complex is usually treated in floristic works as being composed of a single species with two infraspecific taxa: var. gigantea and var. serotina. Recent studies by Beaudry revealed that the complex is composed of individuals of three different chromosome numbers. He proposed that the individuals at each ploidy level be treated as belonging to separate species: S. gigantea, 2n = 18; S. serotina, 2n = 36; and S. shinnersii, 2n = 54. Chromosome counts reported in this paper of individuals of the S. gigantea complex from a wide geographic range verify the existence of the three different ploidy levels. Evaluation of the morphological characters of these vouchers, however, shows that plants with different chromosome numbers cannot be consistently separated using morphological characters. It is proposed, therefore, that the complex be treated as a single species without any infraspecific categories.


Biologia ◽  
2008 ◽  
Vol 63 (3) ◽  
Author(s):  
Petr Šmarda

AbstractUsing flow cytometry in fresh plants and herbarium vouchers, DNA ploidy levels for 411 individuals of 44 taxa of the genus Festuca, including 4 natural hybrids, originating from 237 sites in Austria, Bulgaria, Croatia, Czech Republic, Estonia, Germany, Hungary, Italy, Poland, Romania, Slovakia, Slovenia, and Switzerland were estimated. The following taxa and DNA ploidy levels are reported: F. airoides (2n ≈ 2x), F. alpestris (2n ≈ 2x), F. alpina s.l. (2n ≈ 2x), F. amethystina subsp. amethystina (2n ≈ 4x), F. bosniaca subsp. bosniaca (2n ≈ 2x), F. brevipila (2n ≈ 6x), F. bucegiensis (2n ≈ 2x), F. carnuntina (2n ≈ 6x), F. csikhegyensis (2n ≈ 4x), F. csikhegyensis × F. eggleri (2n ≈ 4x), F. dalmatica (2n ≈ 4x), F. duvalii (2n ≈ 4x), F. eggleri (2n ≈ 2x, 4x), F. filiformis (2n ≈ 2x), F. glauca (2n ≈ 6x), F. heterophylla (2n ≈ 4x), F. inops (2n ≈ 2x), F. laevigata (2n ≈ 8x), F. laxa (2n ≈ 4x), F. lemanii (2n ≈ 6x), F. norica (2n ≈ 2x), F. ovina subsp. ovina (2n ≈ 2x), F. ovina subsp. guesfalica (2n ≈ 4x), F. ovina × F. pallens (2n ≈ 4x), F. pallens (2n ≈ 2x, 3x), F. pallens × F. pseudodalmatica (2n ≈ 3x, 4x), F. pirinica (2n ≈ 2x), F. polesica (2n ≈ 2x), F. psammophila subsp. dominii (2n ≈ 2x), F. pseudodalmatica (2n ≈ 4x), F. pseudovina (2n ≈ 2x), F. quadriflora (2n ≈ 4x), F. rupicola (2n ≈ 6x), F. rupicola × F. vaginata (2n ≈ 3x, 4x), F. saxatilis (2n ≈ 6x), F. stricta subsp. bauzanina (2n ≈ 8x), F. supina (2n ≈ 4x), F. tatrae (2n ≈ 2x), F. valesiaca (2n ≈ 2x), F. versicolor subsp. pallidula (2n ≈ 2x), F. versicolor subsp. versicolor (2n ≈ 2x), F. violacea subsp. puccinellii (2n ≈ 2x), F. wagneri (2n ≈ 4x), F. xanthina (2n ≈ 2x). In F. pallens, up to 12-year-old herbarium specimens were proved to be suitable for DNA ploidy level measurements with flow cytometry.DNA ploidy levels of F. bucegiensis, F. bosniaca, and F. versicolor subsp. pallidula are reported here for the first time. The taxonomy of some polyploid complexes and several records of mixed ploidy level populations are briefly discussed. Festuca pseudodalmatica and its hybrid F. × krizoviensis were first recognised as native to the Czech Republic, and F. brevipila as native to Hungary. Also some new records of F. filiformis, F. brevipila, and F. wagneri from Slovakia are reported.


1966 ◽  
Vol 66 (9) ◽  
pp. 169-237 ◽  
Author(s):  
Trevor G. Walker

SynopsisResults are presented of a cytological survey of the Pteridophyte flora of Jamaica. Approximately 270 species or cytotypes were investigated, only a few of which have previously been investigated from other parts of the world. Several genera have been cytologically examined for the first time and their phylogeny has been discussed in the light of these findings. A number of species complexes and interspecific hybrids have been revealed. The overall statistics of the survey are compared with those compiled from an investigation of the Pteridophyte flora of Ceylon, by Manton and Sledge (1954). Finally, endemic species are discussed in the light of the cytological results and the time known to have been available for their establishment in Jamaica.


2004 ◽  
Vol 129 (1) ◽  
pp. 77-80 ◽  
Author(s):  
Loreto Araneda ◽  
Paulina Salas ◽  
Leví Mansur

Few cytological studies have been conducted on the endemic Chilean genus Leucocoryne, which is comprised of 14 species and a number of populations whose taxonomy has not been elucidated. Eleven species/populations of Leucocoryne have been examined cytologically and L. ixioides (Hook.) Lindl., L. coquimbensis var coquimbensis F.Phil., L. narcissoides R. Phil., L. sp. `Alcones', L. sp. `Talinay' and L. sp. `Combarbalá' were observed to be 2n = 18; L. purpurea Gay, L. sp. `Ñague', L. sp. `Alicahue' and L. sp. `Pichicuy' are 2n = 10 and L. coquimbensis var alba had 2n = 14. Furthermore, a natural hybrid population of L. purpurea and L. coquimbensis var coquimbensis had individuals with 2n = 14 and 2n = 22 chromosomes in addition to the normal complement of 2n = 10 and 2n = 18. The results indicate that Leucocoryne with the exception of L. coquimbensis var alba is typically either 2n = 10 or 2n = 18 with a similar number of species or populations at each ploidy level. Furthermore, the hybrid population demonstrated that there is gene flow between the species at different ploidy levels.


2005 ◽  
Vol 54 (1-6) ◽  
pp. 42-44 ◽  
Author(s):  
P. O. Adebola ◽  
J. A. Morakinyo

Abstract This paper reports the results of chromosome countings in four wild Cola species (Cola lateritia, C. ballayi, C. verticillata and C. gigantea). Cytological investigation of these species gave a constant mitotic chromosome counts of 2n = 4x = 40 for the first time. The karyotypes were found to consist mostly of metacentric and submetacentric chromosomes. In addition to confirming the chromosome numbers and ploidy levels in these species, the results also reveals high symmetry and homogeneity of the karyotypes with those of the cultivated species (C. nitida and C. acuminata) already reported. The similarity in chromosome morphology between the cultivated and wild species indicate their common origin and suggests the possibility of using these wild species as bridges for gene transfer in Cola breeding programmes involving interspecific hybridization.


HortScience ◽  
2010 ◽  
Vol 45 (7) ◽  
pp. 1029-1033 ◽  
Author(s):  
Todd J. Rounsaville ◽  
Thomas G. Ranney

An extensive survey of genome sizes and ploidy levels was conducted for a diverse collection of Berberis and Mahonia taxa (Berberidaceae). Propidium iodide flow cytometric analysis was conducted using Pisum sativum L. ‘Ctirad’ (2C DNA = 8.76 pg) as an internal standard to determine genome sizes. Mean 1CX genome sizes varied between the two Mahonia subgenera (Occidentales = 1.17 ± 0.02, Orientales = 1.27 ± 0.01), whereas those of Berberis subgenera were similar (Australes = 1.45 ± 0.03, Septentrionales = 1.47 ± 0.02) and each significantly larger than those of Mahonia. Traditional cytology was performed on representative species to calibrate genome sizes with ploidy levels. Polyploidy among both wild and cultivated taxa was found to be rare. Although the majority of species were determined to be diploid with 2n = 2x = 28, artificially induced autopolyploid Berberis thunbergii seedlings were confirmed to be tetraploid and an accession of Mahonia nervosa was confirmed to be hexaploid. Genome size and ploidy level reports for the majority of taxa sampled are presented for the first time and are intended to be of use to plant breeders, ecologists, and systematists.


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