A taxonomic study on Centaurea sect. Rhizocalathium and C. sect. Pseudoseridia (Asteraceae, Cardueae–Centaureinae) in Iran

A taxonomic review of Centaurea sect. Rhizocalathium Tzvelev and C. sect. Pseudoseridia Wagenitz in Iran was carried out. The latter, with only one species, Centaurea stevenii, is reported here as new to Iran. In Centaurea sect. Rhizocalathium, C. lasiorhiza is treated as a correct name, C. ispahanica subsp. sirjanensis is described as a new subspecies and C. ispahanica subsp. macrocarpa is proposed as a new combination. Finally, C. ispahanica is typified and its chromosome number is reported for the first time, and a new basic chromosome number for C. sect. Rhizocalathium is proposed.

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Chromosome studies on African plants. 9. Chromosome numbers in Ehrharta (Poaceae: Ehrharteae)

Bothalia ◽

10.4102/abc.v19i1.948 ◽

1989 ◽

Vol 19 (1) ◽

pp. 125-132 ◽

Cited By ~ 2

Author(s):

J. J. Spies ◽

E. J. L. Saayman ◽

S. P. Voges ◽

G. Davidse

Keyword(s):

Chromosome Number ◽

Ploidy Level ◽

Chromosome Numbers ◽

Basic Chromosome Number ◽

B Chromosomes ◽

Basic Chromosome ◽

Cytogenetic Studies ◽

African Plants ◽

First Time

Cytogenetic studies of 53 specimens of 14 species of the genus Ehrharta Thunb. confirmed a basic chromosome number of 12 for the genus. Chromosome numbers for 13 species are described for the first time. The highest ploidy level yet observed in the genus (2n = lOx = 120) is reported for E. villosa var. villosa. B chromosomes were observed in several specimens of four different species.

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Chromosome numbers in some species of Trifolium

Australian Journal of Agricultural Research ◽

10.1071/ar9690883 ◽

1969 ◽

Vol 20 (5) ◽

pp. 883 ◽

Cited By ~ 11

Author(s):

AJ Pritchard

Keyword(s):

Chromosome Number ◽

Chromosome Numbers ◽

Basic Chromosome Number ◽

Basic Chromosome ◽

First Time

The chromosome numbers of 31 species of Trifolium are reported, 18 for the first time. A reduction in basic chromosome number has occurred only in the three most highly specialized subgenera, and polyploids occur mainly in one of the more primitive subgenera.

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Alteration of basic chromosome number by fusion–fission cycles

Genome ◽

10.1139/g95-170 ◽

1995 ◽

Vol 38 (6) ◽

pp. 1289-1292 ◽

Cited By ~ 20

Author(s):

Ingo Schubert ◽

Rigomar Rieger ◽

Jörg Fuchs

Keyword(s):

Chromosome Number ◽

Vicia Faba ◽

Karyotype Evolution ◽

Basic Chromosome Number ◽

Metacentric Chromosome ◽

Field Bean ◽

Basic Chromosome ◽

Chromosome I ◽

First Time

A complete chromosomal fusion–fission cycle is described for the first time. In the field bean, Vicia faba, this cycle probably started with a reversible fusion of two telocentrics giving rise to the standard metacentric chromosome I. The next step was a recent fission of this chromosome into two stable telocentrics eventually followed by a new fusion reconstituting the metacentric chromosome.Key words: karyotype evolution, chromosome number, chromosomal fusion–fission cycle, Vicia faba.

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Chromosome numbers of selected species of Elatine L. (Elatinaceae)

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.2015.036 ◽

2015 ◽

Vol 84 (4) ◽

pp. 413-417 ◽

Cited By ~ 2

Author(s):

Anna Kalinka ◽

Gábor Sramkó ◽

Orsolya Horváth ◽

Attila Molnár V. ◽

Agnieszka Popiela

Keyword(s):

Chromosome Number ◽

Chromosome Numbers ◽

Basic Chromosome Number ◽

Basic Chromosome ◽

First Time

The paper reports chromosome numbers for 13 taxa of Elatine L., including all 11 species occurring in Europe, namely E. alsinastrum, E. ambigua, E. brachysperma, E. brochonii, E. californica, E. campylosperma, E. gussonei, E. hexandra, E. hungarica, E. hydropiper, E. macropoda, E. orthosperma, E. triandra originating from 17, field-collected populations. For seven of them (E. ambigua, E. californica, E. campylosperma, E. brachysperma, E. brochonii, E. hungarica, E. orthosperma) the chromosome numbers are reported for the first time. With these records, chromosome numbers for the whole section Elatinella Seub. became available. Although 2n = 36 was reported to be the most common and the lowest chromosome number in the genus, our data show that out of thirteen species analyzed, six had 36 chromosomes but five species had 54 chromosomes, and the lowest number of chromosomes was 18. These data further corroborates that the basic chromosome number in Elatine is x = 9.

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Karyotype evolution of the genus Eranthis Salisb. (Ranunculaceae)

Проблемы ботаники Южной Сибири и Монголии ◽

10.14258/pbssm.2020075 ◽

2020 ◽

Vol 19 (2) ◽

pp. 056-060

Author(s):

E. Yu Mitrenina ◽

A. S. Erst

Keyword(s):

Chromosome Number ◽

Comparative Study ◽

Karyotype Evolution ◽

Basic Chromosome Number ◽

B Chromosomes ◽

Basic Chromosome ◽

Meristematic Cells ◽

Pericentric Inversions ◽

Root Meristematic Cells ◽

First Time

We have conducted comparative study of karyotypes for nine Eranthis Salisb. species: E. bulgarica (Stef.)Stef., E. hyemalis (L.) Salisb., E. longistipitata Regel (section Eranthis), E. byunsanensis B. Y. Sun, E. lobulata W. T.Wang, E. pinnatifida Maxim., E. sibirica DC., E. stellata Maxim., and E. tanhoensis Erst (section Shibateranthis). Thespecies-specifity of karyotypes was established for all species investigated. The chromosomes of each species weremedium or large in size (4–12 µm). Besides E. sibirica and E. tanhoensis, all the investigated specimens had diploidcytotypes with 2n = 16 and the basic chromosome number x = 8. Plants from five E. sibirica populations were tetraploidand hexaploid with x = 7, 2n = 28 and 2n = 42 respectively. Plants from seven E. tanhoensis populations were diploid withx = 7 and 2n = 14. Diploid karyotypes of Eranthis included 4–5 pairs of large equal-armed (metacentric) chromosomes,and 2–4 pairs of unequal-armed chromosomes belonging to different morphological types (submetacentric, subtelocentric,and acrocentric ones). We have revealed B chromosomes in root meristematic cells of E. lobulata and E. tanhoensis forthe first time. We suppose that the key developments in Eranthis karyotype`s evolution were pericentric inversions,polyploidy, and probably translocations.

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Karyotype analysis of medicinal plant Liriope spicata var. prolifera (Liliaceae)

Biologia ◽

10.2478/s11756-009-0069-8 ◽

2009 ◽

Vol 64 (4) ◽

Cited By ~ 1

Author(s):

Qun Zhou ◽

Jianqiu Zhou ◽

Jiachun Chen ◽

Xiaogang Wang

Keyword(s):

Chromosome Number ◽

Medicinal Plant ◽

Endemic Species ◽

Secondary Constriction ◽

Karyotype Analysis ◽

Basic Chromosome Number ◽

Separate Species ◽

Basic Chromosome ◽

First Time

AbstractKaryotype of Liriope spicata var. prolifera, a Chinese endemic species, was described in detail for the first time. Its proto-variety L. spicata was also investigated for comparison. The basic chromosome number of these two species was x = 18. L. spicata var. prolifera, recorded as triploid 2n = 54, consisted of 30 metacentric chromosomes and 24 submetacentric chromosomes. Only one chromosome of the 11th group had a secondary constriction with a satellite in the short arm. L. Spicata was tetraploid 2n = 72 and consisted of four sets of 6 submetacentric chromosomes and 12 metacentric chromosomes without visible satellites. This paper provides further available data on Liriope chromosomes, and also indicates that L. spicata var. prolifera and L. spicata are probably separate species.

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Extraction of disomic addition lines of Brassica napus – B. nigra

Genome ◽

10.1139/g89-463 ◽

1989 ◽

Vol 32 (3) ◽

pp. 408-413 ◽

Cited By ~ 36

Author(s):

J. Jahier ◽

A. M. Chèvre ◽

A. M. Tanguy ◽

F. Eber

Keyword(s):

Brassica Napus ◽

Chromosome Number ◽

Anther Culture ◽

Genome Structure ◽

Basic Chromosome Number ◽

Meiotic Pairing ◽

Addition Lines ◽

Basic Chromosome ◽

Disomic Addition Lines ◽

First Time

The hybrid Brassica napus × B. nigra was produced and backcrossed three times to rapeseed. BC3 genotypes with one or two additional chromosomes were either selfed or haplodiploidized by using anther culture followed by colchicine doubling. Thirty-four fertile disomic addition lines have so far been obtained. Meiotic pairing in most of them was close to 20 II at metaphase I of meiosis. Their characterization is in progress. This material obtained for the first time in B. napus should be of great interest in the study of genome structure and basic chromosome number in Brassica species.Key words: Brassica, genome, disomic addition lines, meiotic behaviour.

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Cytotaxonomic Study of Hypodematium (Hypodematiaceae) from China

Phytotaxa ◽

10.11646/phytotaxa.161.2.1 ◽

2014 ◽

Vol 161 (2) ◽

pp. 101 ◽

Cited By ~ 6

Author(s):

Renxiang Wang ◽

Wen Shao ◽

Ling Liu

Keyword(s):

Chromosome Number ◽

Chromosome Numbers ◽

Habitat Preferences ◽

Northeast Asia ◽

Basic Chromosome Number ◽

Basic Chromosome ◽

Dry Conditions ◽

Diakinesis Stage ◽

First Time ◽

Meiosis I

Chromosome numbers and reproductive biology of nine species of the fern genus Hypodematium (Hypodematiaceae) from China were investigated. The chromosome numbers of eight species are reported here for the first time: H. daochengensis n=41 (41 II); H. fordii n=40 (40 II), n=80 (40 II+40 I), 2n=120; H. glanduloso-pilosum n=41 (41 II), 2n=82, 2n=123; H. gracile n=41 (41 II); H. hirsutum n= 41 (41 II); H. microleptoides n=41 (41 II); H. sinense n= 40 (40 II) and H. squamuloso-pilosum n=41 (41 II). Two cytotypes, n=82 (41 II+41 I) and 2n=123 in H. crenatum, are reported for the first time. Our results showed that the species with these cytotypes are agamospermous triploids: H. crenatum n = 82 (41 II +41 I), H. glanduloso-pilosum n = 82 (41 II +41 I) and H. fordii n = 80 (40 II +40 I), based on the unequal size and presence of aborted spores in the sporangium, and the allotriploid hybrid chromosomes in the spore mother cell at the diakinesis stage of meiosis I. The remaining species are sexual diploids and tetraploids, based on the chromosome number n = 41 and n =82 at the diakinesis stage of meiosis I of spore mother cells. The relationships among habitat preferences, frond hairs and reproductive modes in Hypodematium are discussed and illustrated. It appears that plants with large fronds and sparse, thin hairs, living in humid and shady places undergo sexual reproduction, while small plants living in sunny and dry conditions with thick hairs undergo agamospermous reproduction. The distribution pattern and basic chromosome number all indicated the basic chromosome number x= 41 was plesiomorphic, whereas x=40 was apomorphic. Chromosome aneuploid changes occurred in this genus. The distribution of the sexual diploids and tetraploids and agamospermous triploids suggests that the genus might have originated in the Himalayas and dispersed from there to northeast Asia and Japan.

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In vitro propagation and cytological analysis of Sophora mollis Royle: an endangered medicinal shrub

Journal of Genetic Engineering and Biotechnology ◽

10.1186/s43141-021-00140-3 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Aakriti Bhandari ◽

Harminder Singh ◽

Amber Srivastava ◽

Puneet Kumar ◽

G. S. Panwar ◽

...

Keyword(s):

Chromosome Number ◽

Average Length ◽

Germplasm Conservation ◽

Basic Chromosome Number ◽

Shoot Tip ◽

Ex Situ ◽

Ms Medium ◽

Basic Chromosome ◽

Shoot Tip Explants

Abstract Background Sophora mollis Royle (family Fabaceae, subfamily-Papilionaceae) is a multipurpose legume distributed in plains and foothills of the North-West Himalaya to Nepal and is facing high risk of extinction due to habitat loss and exploitation by the local people for its fuel and fodder values. Therefore, the present study was conducted to standardize a micropropagation protocol for Sophora mollis by using shoot tip explants and to study the meiotic chromosome count in the species. Results Multiple shoots were induced in shoot tip explants of Sophora mollis in Murashige and Skoog medium supplemented with different concentrations of cytokinins alone (BAP, TDZ, and Kinetin) and in combination with varying concentrations of NAA. MS medium supplemented with BAP (8.9 μM) was observed to be the optimal medium for multiple shoot induction and maximum 25.32 shoots per explant was obtained with average length of 4.5 ± 0.8 cm. In vitro developed shoots were transferred onto rooting media supplemented with different concentrations of auxin (IAA, IBA, and NAA). Maximum 86% rooting was observed in half-strength MS medium supplemented with 21.20 μM NAA with an average of 21.26 roots per culture. In vitro raised plantlets were adapted to greenhouse for better acclimatization and 60% plants were successfully transferred to the open environment. Based on the chromosome counts available from the literature and the current study, the species tend to show a basic chromosome number of x = 9. Conclusion The micropropagation protocol standardized can be helpful for the ex situ mass multiplication and germplasm conservation of the endangered species. Moreover, the ex situ conservation approach will be helpful in actively bridging the gap between ex situ and in situ approaches through the reintroduction of species in the wild. The cytological studies revealed the basic chromosome number x = 9 of the species.

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Relations and evolution in Cheilanthes (Sinopteridaceae, Pteridophita) in Macaronesia and Mediterranean area, deduced from genome analysis of their hybrids

Acta Botanica Malacitana ◽

10.24310/actabotanicaabmabm.v8i.9648 ◽

1983 ◽

Vol 8 ◽

pp. 101-126 ◽

Cited By ~ 2

Author(s):

G. Vida ◽

A. Major ◽

T. Reichstein

Keyword(s):

Chromosome Number ◽

Genome Analysis ◽

Chromosome Doubling ◽

Diploid Species ◽

Mediterranean Area ◽

Basic Chromosome Number ◽

The Other ◽

Experimental Conditions ◽

Natural Group ◽

Basic Chromosome

Nine species of "Cheilantoid ferns" are known to grow in Macaronesia and the Mediterranean basin. Two of them (lacking a pseudo-indusium and having the basic chromosome number X = 29), both aggregate species which we prefer to retain in Notholaena, are not included in this study. The other seven species (with distinct pseudo-indusium and the basic chromosome number X = 30), which we accept as members of the genus Cheilanthes Sw. sensu stricto, were subjected to detailed genome analysis of their natural and experimentally produced hybrids and shown to represent an aggregate of four very distinct ancestral diploids and three allotetraploids. The latter must have once been formed by chromosome doubling in the three diploid hybrids of C. maderensis Lowe with the other three diploid species. Theoretically three more allotetraploids would be possible but their formation has obviously been prevented by the geographical separation of the three respective diploids. The most widely distributed of the tetraploids, i.e. C. pteridioides (Reich.) C.Chr. has also been resynthesized from its ancestors (still sympatric) under experimental conditions. The intermediate morphology of the allotetraploids (as compared with their diploid ancestors) is obviously the reason why their status and existence has so long escaped recognition in Europe. These seven species form a natural group and, in our opinion, should not be divided into sections.

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