Cytogenetic studies in the genus Pentaschistis (Poaceae: Arundinoideae)

Bothalia ◽  
1998 ◽  
Vol 28 (2) ◽  
pp. 231-238 ◽  
Author(s):  
K. C. Klopper ◽  
J. J. Spies

Cytogenetic studies of 45 specimens, representing 16 taxa of the genus Pentaschistis (Nees) Spach confirmed two basic chromosome numbers (x = 7, 13) for the genus. Chromosome numbers for five species and one subspecies are described for the first time, i.e. P. aimides subsp.  jugorum (n = 2x = 14). P. colorata (n = 2x = 14). P densifolia (n = x = 7), P. linui (n = 6x = ± 42), P. rigidissima (n = x = 7, n = 3x = 21) and P viscidula (n = 3x = 21). Polyploidy occurs frequently and new ploidy levels are described m four of the species, namely P airoides (Nees) Stapf subsp. airoides (n = 3x = 21), P. cir- rhulosa (Thunb.) McClean (n = x = 7), P. eriostoma (Nees) Stapf (n = 3x = 39+0-4B) and P rupestris (n = 4x = 28) The majority of species form young polyploid complexes. There seems to be no correlation between cytogenetic data and mor­phological groupings within Pentaschistis.


Bothalia ◽  
1989 ◽  
Vol 19 (1) ◽  
pp. 125-132 ◽  
Author(s):  
J. J. Spies ◽  
E. J. L. Saayman ◽  
S. P. Voges ◽  
G. Davidse

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.



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

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.



Bothalia ◽  
1997 ◽  
Vol 27 (1) ◽  
pp. 75-82 ◽  
Author(s):  
J. J. Spies ◽  
S. M. C. Van Wyk ◽  
I. C. Nieman ◽  
E. J. L. Liebenberg

This is a report on chromosome numbers for the tribe Poeae, which is represented in South Africa mainly by naturalized exotics. Chromosome numbers of 67 specimens, representing 26 species and 11 genera, are presented. These numbers include the first reports on Poa binata Nees (n = 3x = 21 and n = 4x = 28), Puccinellia acroxantha C.A.Sm. CE.Hubb. (n = 3x = 21) and P. angusta (Nees) C.A.Sm. C.E.Hubb. (n = x = 7). New ploidy levels are reported for Catapodium rigidum (L.) CE.Hubb.(n = 2x = 14), Festuca caprina Nees (n = 2x = 14) and F. scabra Vahl (n = x = 7).



Bothalia ◽  
1991 ◽  
Vol 21 (2) ◽  
pp. 163-170 ◽  
Author(s):  
J. J. Spies ◽  
E. Van der Merwe ◽  
H. Du Plessis ◽  
E. J. L. Saayman

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.



1969 ◽  
Vol 20 (5) ◽  
pp. 883 ◽  
Author(s):  
AJ Pritchard

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.



Taxonomy ◽  
2021 ◽  
Vol 1 (4) ◽  
pp. 290-301
Author(s):  
John C. Semple ◽  
Jie Zhang ◽  
Rachel E. Cook ◽  
Bambang Agus Suripto

Chromosome numbers are reported here for the first time from 117 individuals of Solidago rugosa and S. fistulosa. Including 178 previously published reports for the two species plus S. latissimifolia, chromosome numbers have been determined from 295 individuals from 269 locations. Only diploids (2n = 18) were found throughout the range of S. fistulosa on the coastal plain in the eastern U.S.A. (44 counts). Diploids (2n = 18) were found in the northern portion of the range of S. latissimifolia, and tetraploids (2n = 36) and hexaploids (2n = 54) were found in the central and southern portions of the range (nine counts in total). Diploids (2n = 18) were found throughout the range of S. rugosa in much of eastern North America in four of the five varieties (northern var. rugosa, var. sphagnophila; southern var. aspera and var. celtidifolia). Tetraploids (2n = 36) were found in all four of these varieties and exclusively in var. cronquistiana in the southern high Appalachian Mountains. Hexaploids (2n = 54) were found in var. sphagnophila at scattered locations. One possible hexaploid in var. rugosa was found in the Allegheny Mountains. The diversity in ploidy levels was independent of the size of the range and the diversity of growing conditions among the three species of S. subsect. Venosae.



2021 ◽  
Vol 106 ◽  
pp. 234-244
Author(s):  
Ana Isabel Honfi ◽  
Osvaldo Morrone† ◽  
Fernando Omar Zuloaga

Chromosome numbers and ploidy levels of 24 accessions of 17 species of tribe Panicoideae from Argentina, Cuba, and Brazil are given. Most of the studied species are endemics. The studied taxa are: Axonopus aureus P. Beauv., Dichanthelium aequivaginatum (Swallen) Zuloaga, D. stipiflorum (Renvoize) Zuloaga, D. surrectum (Chase ex Zuloaga & Morrone) Zuloaga, Homolepis isocalycia (G. Mey.) Chase, Paspalum arenarium Schrad., P. blodgettii Chapm., P. capillifolium Nash, P. coryphaeum Trin., P. distortum Chase, P. durifolium Mez, P. lindenianum A. Rich., P. oligostachyum Salzm. ex Steud., P. pumilum Nees, P. scutatum Nees ex Trin., P. strigosum Döll ex Chase, and Plagiantha tenella Renvoize; of these, the chromosome numbers of D. aequivaginatum, D. stipiflorum, D. surrectum (n = 9), Homolepis isocalycia (n = 20), Paspalum capillifolium, P. distortum, P. lindenianum, P. oligostachyum, and P. strigosum (n = 10) are presented for the first time. A new diploid cytotype (n = 10) for Paspalum blodgettii was found.



Author(s):  
Pedro Jara-Seguel ◽  
Gladys Lara ◽  
María Paz García ◽  
Iván Valdebenito

<p>A database containing data from cytogenetic studies of Chilean fish species is documented for the first time. The cytogenetic data compiled for Chilean fishes include 28 species belonging to 11 families, 9 orders and 16 genera, taking as reference 18 publications since 1972. The application of a variety of cytogenetic methods has provided information on chromosome number, karyotype morphology, genome size, and /or location of different DNA sequences. These data represent only ca. 2.7% of Chile’s fish diversity.</p>



2015 ◽  
Vol 84 (4) ◽  
pp. 413-417 ◽  
Author(s):  
Anna Kalinka ◽  
Gábor Sramkó ◽  
Orsolya Horváth ◽  
Attila Molnár V. ◽  
Agnieszka Popiela

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.



Turczaninowia ◽  
2021 ◽  
Vol 24 (1) ◽  
pp. 89-97
Author(s):  
Elena Yu. Zykova ◽  
Tatyana V. An’kova ◽  
Maria N. Lomonosova

Chromosome numbers (2n) in 10 invasive and potentially invasive plant species from the families Asteraceae, Brassicaceae, Caryophyllaceae, Fabaceae, Malvaceae, Oxalidaceae, Poaceae and Solanaceae are reported on the samples collected in the Republic of Altai. To determine the ploidy levels, we used methods of direct chromosome counting and flow cytometry in some cases. Among them, chromosome complements were first examined in Russia for Eruca vesicaria subsp. sativa (2n = 22). Psammophiliella muralis (2n = 34), Medicago sativa subsp. varia (2n ≈ 32; 2C = 4.8 pg) and Solanum nigrum (2n = 48) were first studied from Siberia. Malva verticillata (2n = 42), Oxalis dillenii (2n = 24), Lolium perenne (2n = 14) and Setaria faberi (2n = 36) were first studied from the Republic of Altai. Tetraploid cytotype and genome size of Picris hieracioides (2n = 4x = 20; 2C = 8.89 pg) were discovered for the first time. Common distribution and the history of floristic findings of these species in the Republic of Altai are given. Previously published data on chromosome numbers from Russia are cited.



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