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

Bothalia ◽  
1989 ◽  
Vol 19 (1) ◽  
pp. 125-132 ◽  
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.

Chromosome numbers in some species of Trifolium

1969 ◽  
Vol 20 (5) ◽  
pp. 883 ◽  
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.

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

2015 ◽  
Vol 84 (4) ◽  
pp. 413-417 ◽  
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 <em>Elatine</em> L., including all 11 species occurring in Europe, namely <em>E. alsinastrum</em>, <em>E. ambigua</em>, <em>E. brachysperma</em>, <em>E. brochonii</em>, <em>E. californica</em>, <em>E. campylosperma</em>, <em>E. gussonei</em>, <em>E. hexandra</em>, <em>E. hungarica</em>, <em>E. hydropiper</em>, <em>E. macropoda</em>, <em>E. orthosperma</em>, <em>E. triandra</em> originating from 17, field-collected populations. For seven of them (<em>E. ambigua</em>, <em>E. californica</em>, <em>E. campylosperma</em>, <em>E. brachysperma</em>, <em>E. brochonii</em>, <em>E. hungarica</em>, <em>E. orthosperma</em>) the chromosome numbers are reported for the first time. With these records, chromosome numbers for the whole section <em>Elatinella</em> Seub. became available. Although 2<em>n</em> = 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 <em>Elatine</em> is <em>x</em> = 9.

scholarly journals Karyotype evolution of the genus Eranthis Salisb. (Ranunculaceae)

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.

Cytogenetic studies in some representatives of the subfamily Pooideae (Poaceae) in South Africa. 1. The tribe Aveneae, subtribe Aveninae

Bothalia ◽  
1996 ◽  
Vol 26 (1) ◽  
pp. 53-61 ◽  
Author(s):  
J. J. Spies ◽  
S. K. Spies ◽  
S. M. C. Van Wyk ◽  
A. F. Malan ◽  
E. J. L. Liebenberg
Keyword(s):  
South Africa ◽  
Chromosome Number ◽  
Chromosome Numbers ◽  
Basic Chromosome Number ◽  
Ploidy Levels ◽  
Basic Chromosome ◽  
The World ◽  
Cytogenetic Studies

This is a report on chromosome numbers for 14 species of the subtribe Aveninae. which is largely naturalized in South Africa. This is the first chromosome number report for Helictotrichon longifolium (Nees) Schweick. (n = 14). H. longum (Stapf)Schweick. (n = 14). H. namaquensis Schweick. (n = 14) and Lophochloa cristata (L.) Hyl. (n = 7, 21/2. 14). The subtribe has a basic chromosome number of seven, and fewer ploidy levels occur in the naturalized species in South Africa than in the same species in other parts of the world. All tetraploid specimens were alloploids.

scholarly journals Cytotaxonomic Study of Hypodematium (Hypodematiaceae) from China

Phytotaxa ◽  
2014 ◽  
Vol 161 (2) ◽  
pp. 101 ◽  
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.

Chromosome studies on African plants. 11. The tribe Andropogoneae (Poaceae: Panicoideae)

Bothalia ◽  
1994 ◽  
Vol 24 (2) ◽  
pp. 241-246 ◽  
Author(s):  
J. J. Spies ◽  
T. H. Troskie ◽  
E. Van der Vyver ◽  
S. M. C Van Wyk
Keyword(s):  
Chromosome Number ◽  
Basic Chromosome Number ◽  
Basic Chromosome ◽  
African Plants

Representative specimens of various species of the genera  Andropogon L.,  Cymbopogon Spreng.,  Elionurus Kunth ex Willd.,  Hyparrhenia Foum. and  Hyperthelia Clayton were cytogenetically studied. All specimens had a secondary basic chromosome number of ten. Polyploidy, either as alloploidy or segmental alloploidy. was frequent. The taxa studied represent mature polyploid complexes.  

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

Phytotaxa ◽  
2014 ◽  
Vol 174 (1) ◽  
pp. 43 ◽  
Author(s):  
Kazem Negaresh ◽  
MOHAMMAD REZA RAHIMINEJAD ◽  
MASSOUD RANJBAR
Keyword(s):  
Chromosome Number ◽  
Basic Chromosome Number ◽  
New Combination ◽  
Taxonomic Study ◽  
Basic Chromosome ◽  
New Subspecies ◽  
Taxonomic Review ◽  
First Time

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.

Basic chromosome numbers and polyploid levels in some South African and Australian grasses (Poaceae)

Bothalia ◽  
1991 ◽  
Vol 21 (2) ◽  
pp. 163-170 ◽  
Author(s):  
J. J. Spies ◽  
E. Van der Merwe ◽  
H. Du Plessis ◽  
E. J. L. Saayman
Keyword(s):  
South Africa ◽  
South African ◽  
Chromosome Numbers ◽  
B Chromosomes ◽  
Basic Chromosome ◽  
First Time ◽  
Chromosomal Behaviour

Chromosome numbers of 46 specimens of grasses, involving 24 taxa from South Africa and Australia, have been determined during the present study. For the first time chromosome numbers are given for Eragrostis sarmentosa (Thunb.) Trin. (n = 20). Panicum aequinerve Nees (n = 18),  Digitaria argyrograpta (Nees) Stapf (n = 9) and D. maitlandii Stapf C.E. Hubb. (n = 9). Additional polyploid levels are described for Diplachne fusca (L.) Beauv. ex Roem. Schult. (n = 10) and Digitaria diagonalis (Nees) Stapf var.  diagonalis (n = 9).B-chromosomes were observed in several different specimens. The presence of B-chromosomes often results in abnormal chromosomal behaviour during meiosis.

scholarly journals Studies on Basic Chromosome Number, Ploidy Level, Chromosomal Association and Configuration and Meiotic Behavior in Mulberry (Morus Spp.)

2021 ◽  
Author(s):  
Koluru Honnegowda Venkatesh
Keyword(s):  
Ploidy Level ◽  
Chromosome Numbers ◽  
Pollen Fertility ◽  
Basic Chromosome Number ◽  
Basic Chromosome ◽  
Chromosomal Association ◽  
Morus Spp ◽  
Bombyx Mori L ◽  
Normal Meiosis ◽  
Silkworm Bombyx Mori

Mulberry leaves are primary food for silkworm, Bombyx mori L. to feed silkworms and harvest quality silk cocoons. Mulberry belongs to family Moraceae and includes 60 species found distributed in both Hemisphere. In mulberry, chromosome numbers are varies from 2n = 28 to 22n = 308 (Diploid to Decosoploid) with ploidy level x to 22x. Based on chromosome numbers and meiotic behaviors x = 14 has been considered as basic chromosome numbers of the genus. In the present study, two diploids, two uneuploids, two triploids and two teteraploids mulberry varieties were selected for detailed chromosomal numbers and meiotic behaviors belongs to three species, namely Morus indica, Morus alba and Morus latifolia. Varieties, Vishaala and Kosen were diploids with 2n = 2x = 28 chromosomes and varieties Ber-S1 and S13 were uneuploids with 2n = 30 chromosomes belongs Morus indica. Varieties NAO Khurkul and KPG-1 were triploids with 2n = 3x = 42 chromosomes belongs to Moru alba and varieties Kokuso and Icheihei were tetraploids with 2n = 4x = 56 chromosomes. Diploids and uneuploids were showed normal meiosis with high pollen fertility and triploids and teteraploids were showed abnormal meiosis with low pollen fertility, due to virtue of higher ploidy level have been discussed in this chapter.

scholarly journals Fertility of Triploid Highbush Blueberry

1991 ◽  
Vol 116 (2) ◽  
pp. 336-341 ◽  
Author(s):  
N. Vorsa ◽  
James R. Ballington
Keyword(s):  
Gene Transfer ◽  
Chromosome Number ◽  
Chromosome Numbers ◽  
2N Gametes ◽  
Basic Chromosome Number ◽  
Highbush Blueberry ◽  
Pollen Stainability ◽  
Frequency Distributions ◽  
Basic Chromosome ◽  
2N Gamete

Eight highbush blueberry (V. corymbosum L.) triploids (2n = 3x = 36) were crossed with diploids (2n = 2x = 24), tetraploids (2n = 4x = 48), and hexaploids (2n = 6x = 72). No plants were recovered from 4021 3x × 2x crosses. One triploid was relatively fertile in 3x × 4x and 3x × 6x crosses, which is most likely attributable to 2n gamete production in the triploid. The lack of fertility of triploids, which do not produce 2n gametes, in crosses with diploids and tetraploids suggests that the production of gametes with numerically balanced (n = 12 or 24) chromosome numbers is extremely low. In addition, the inability to recover progeny from 3x × 2x crosses also suggests that aneuploid gametophytes and/or zygotes, including trisomics, are inviable in blueberry. Pollen stainability was also highly reduced in triploids. Frequency distributions of anaphase I pole chromosomal constitutions of three triploids were significantly different from one another. Two of the three distributions were shifted toward the basic chromosome number of 12, with one triploid having 25% poles with 12 chromosomes. However, the sterility of 3x × 2x and 2x × 3x crosses indicates that lagging chromosomes during meiotic anaphases are probably not excluded from gametes, resulting in unbalanced gametes in blueberry. Triploids can be used as a bridge to facilitate gene transfer from the diploid and tetraploid levels to the hexaploid level in blueberry.

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