Karyology

Unlike other tribes of Gentianaceae, Exaceae have so far received little attention regarding their karyological evolution. Indeed, only 35 chromosome number counts (19 species) have been referenced to date, representing only a negligible fraction of the tribal diversity. In this paper, we performed an intensive chromosome count on material collected in the field (South and central Africa, plus Madagascar), encompassing 155 populations and c. 60 species from four genera of Exaceae, including Exacum, Ornichia, Sebaea and Tachiadenus. Fifty nine species (14 Exacum, one Ornichia, 42 Sebaea and two Tachiadenus) were examined for the first time, revealing a broad set of chromosome numbers (2n = 18, 28, 32, 36, 42, 56) and the occurrence of polyploid systems within Exacum and Sebaea. These results allow us to postulate x = 7, 8 or 9 as possible base chromosome numbers for Exaceae and emphasize the importance of both dysploidy and polyploidy processes in the evolution of the tribe. Finally, chromosome numbers appear to be associated to some morphological or geographical traits, suggesting new systematic combinations and likely active speciation patterns in the group. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158, 556–566.

This study presents investigations on the morphological, anatomical, karyological and ecological features a perennial shrubby species Teucrium microphyllum Desf., belonging to Sect. Chamaedrys (Mill.) Schreb., endemic to Central and South Aegean Islands and Southwest Anatolia. Description of T. microphyllum was expanded. The morphological features indumentum of stem, leaf, calyx and corolla were determined using stereo-microscope and scanning electron microscope. Cross-sections of stem and leaf was taken using razor by manually. Stem is rectangular and has 4-5-layered collenchyma in the corners. Leaf is bifacial. There are 2(-3)-layered palisade parenchyma and spongy parenchyma has 2-4 layers. Chromosome number was determined with using squash preparation method and the somatic chromosome number was found as 2n = 30. The basic chromosome number of the species was x = 15. The karyotype formula of this species consists of fifteen median chromosome pairs. The soil samples were collecte...

In the Ćićarija, the mountain range in northern Istria between Trieste in the west and Rijeka in the east, occur 5 species of the genus Aconitum. Aconitum anthora is rare in the hills north of the mount Slavnik. Aconitum variegatum grows only in the northwestern part, southeastwards to the mountains Žabnik and Žbevnica. Aconitum degenii is known until now only from the mountains Planik and Vojak. Yellow flowering Aconites of the subgenus Lycoctonum can be found in the whole mountain range, but they have not been differentiated yet. Here the characteristics, which differ the two species Aconitum lupicida and Aconitum lycoctonum, are explained and shown in figures and in a table. The main difference of the leaf shape is expressed by leaf indices (following WARNCKE 1964). The distribution of all species is shown in a dot map, and a key for the determination is given.

Here we describe Allium telmatum Bogdanović, Brullo, Giusso & Salmeri, a new species of Allium sect. Codonoprasum from North Dalmatia (Croatia). Its chromosome number (2n = 32), karyotype, leaf anatomy, ecology and taxonomical relationships are examined. Several features, such as phenology (flowering in autumn), occurrence in coastal salt marshes, tetraploid chromosome number, and morphology, indicate that it is most closely related to the Tyrrhenian species Allium savii. On the basis of our herbarium survey, we present here a distribution map of the autumn-flowering species of Allium sect. Codonoprasum in the Mediterranean area.

Momordica charantiaL. (Cucurbitaceae) is a commonly cultivated functional food plant. In the present study, karyological variation among 34 accessions ofM. charantiaoriginating from the Indian subcontinent (Bangladesh, India and Pakistan) and Thailand was evaluated. Ploidy levels ranging from diploid (2n= 22) to hexaploid (2n= 66) were observed. Hexaploidy inM. charantiais reported herein for the first time. Chromosome length ranged from 0.8 to 2.9 μm. The hexaploid accessions had submetacentric and subtelocentric chromosomes. All accessions harboured median and submedian chromosomes. Only one hexaploid accession (TOT1140) had chromosomes with subterminal centromeres. There was considerable variation in chromosome length and chromosome arm ratio.

One of the largest monocotyledonous genus in the Amaryllidaceae family is the Allium genus that includes approximately 900 species. This study aimed to examine the variations and clustering of eight Iranian endemic Allium species based on karyotype features. The species were collected from wild habitats across different geographical areas of Iran. A. sativum, A. stipitatum, A. fistolosum, A. umbellicatum, A. stamineum, A. lenkoranicum, and A. rubellum, were diploids (2n = 2x = 16), but A. atroviolaceum was triploid (2n = 3x = 24). The results represent x = 8 for basic chromosome numbers in all species. Analysis of variance showed significant interspecific variations for all eight chromosomal parameters tested. The mean of chromosome lengths was 11.19 μm, varied from 8.59 μm to 13.81 μm for A. atroviolaceum and A. stipitatum, respectively. In all species, the chromosome types were determined as mostly metacentric (m) and submetacentric (sm), formed five different karyotype formulas of 16m (A. stipitatum, A. fistolosum, A. stamineum), 14m+2sm (A. sativum, A. rubellum), 12m+4sm (A. lenkoranicum), 10m+6sm (A. umbellicatum), and 24m (A. atroviolaceum). According to Stebbins' classification, all karyotypes were grouped in the 1A class and represented the most symmetrical karyotypes. The information obtained from karyotype and chromosome morphology has an appreciable value in understanding the taxon evolution and interrelations.

The present study determines the morphological, anatomical, palynological, karyological, chorological features and conservation status of the rediscovered rare endemic Turkish taxon Cota fulvida (Grierson) Holub. (Asteraceae) after ca.110 years. C. fulvida distributes naturally in Gölcük Plateau (Türkmen Mountain), Eski?ehir-Turkey. In the cross-sections of the root of C. fulvida, the pith was found completely covered by xylem cells. As to stem, it was observed that large parenchymatic cells were present in the pith of the stems. Leaves are equifacial and amphistomatious having amaryllis type of stomata. They are mesomorphic. Stomata are anisocytic. The results of the light and scanning electron microscope investigation revealed that the pollen grains of C. fulvida are tricolporatae, amb shape triangular, pollen shape spheroidal. Exine tectatae-echinate. The somatic chromosome number of C. fulvida was found to be 2n =18 without any satellite. It is considered "Critically Endang...

Momordica charantia L. (Cucurbitaceae) is a commonly cultivated functional food plant. In the present study, karyological variation among 34 accessions of M. charantia originating from the Indian subcontinent (Bangladesh, India and Pakistan) and Thailand was evaluated. Ploidy levels ranging from diploid (2n ¼ 22) to hexaploid (2n ¼ 66) were observed. Hexaploidy in M. charantia is reported herein for the first time. Chromosome length ranged from 0.8 to 2.9 mm. The hexaploid accessions had submetacentric and subtelocentric chromosomes. All accessions harboured median and submedian chromosomes. Only one hexaploid accession (TOT1140) had chromosomes with subterminal centromeres. There was considerable variation in chromosome length and chromosome arm ratio.

Cytogenetic approaches are used in systematic studies implying differences between species and variation between populations. In this study, morphology of chromosomes and chromosome number of 210 specimens of 23 rodent species from different localities of Iran were investigated. Specimens belong to five families comprising Dipodidae (Allactaga elater (2n=48, FNa=92); A. williamsi (2n=48, FNa=92); A. tuossi (2n=48, FNa=92); A. euphratica (2n=48, FNa=92); A. hotsoni (2n=48, FNa=92); Jaculus jaculus (2n=48, FNa=88 and 92); Pygeretmus pumilio (2n=48, FNa= 82 to 92)), family Cricetidae (Microtus socialis (2n=62, FNa=60); M. qazvinensis (2n=54, FNa=52); M. transcaspicus (2n=52, FNa=50); M. levis (2n=54, FNa=52); M. paradoxus (2n=62, FNa=60); Ellobius talpinus (2n=54, FNa=52); E. fuscocapillus (2n=36, FNa=54); Cricetulus migratorius (2n=22, FNa=38 and 40); Mesocricetus brandti (2n=42, FNa=78)), family Gliridae (Dryomys nitedula (2n=48, FNa=84 to 90)), family Scuridae (Funambulus pennantii ...

Micromys minutus was recorded from six localities in Turkish Thrace. The external, cranial and karyological peculiarities of the specimens were determined. The dorsal colour of the specimens is dark brownish, being lighter on the sides, but the rostrum and cheek are markedly ochre. Mean tail length relative to body length is 90.5%, and the occipito-nasal length is 18.1 mm. The diploid number of chromosomes was 2n = 68 with NF = 136 and NFa = 132.

Momordica charantiaL. (Cucurbitaceae) is a commonly cultivated functional food plant. In the present study, karyological variation among 34 accessions ofM. charantiaoriginating from the Indian subcontinent (Bangladesh, India and Pakistan) and Thailand was evaluated. Ploidy levels ranging from diploid (2n= 22) to hexaploid (2n= 66) were observed. Hexaploidy inM. charantiais reported herein for the first time. Chromosome length ranged from 0.8 to 2.9 μm. The hexaploid accessions had submetacentric and subtelocentric chromosomes. All accessions harboured median and submedian chromosomes. Only one hexaploid accession (TOT1140) had chromosomes with subterminal centromeres. There was considerable variation in chromosome length and chromosome arm ratio.

This study presents investigations on the morphological, anatomical, karyological and ecological features a perennial shrubby species Teucrium microphyllum Desf., belonging to Sect. Chamaedrys (Mill.) Schreb., endemic to Central and South Aegean Islands and Southwest Anatolia. Description of T. microphyllum was expanded. The morphological features indumentum of stem, leaf, calyx and corolla were determined using stereo-microscope and scanning electron microscope. Cross-sections of stem and leaf was taken using razor by manually. Stem is rectangular and has 4-5-layered collenchyma in the corners. Leaf is bifacial. There are 2(-3)-layered palisade parenchyma and spongy parenchyma has 2-4 layers. Chromosome number was determined with using squash preparation method and the somatic chromosome number was found as 2n = 30. The basic chromosome number of the species was x = 15. The karyotype formula of this species consists of fifteen median chromosome pairs. The soil samples were collecte...

Botanical Journal of the Linnean Society, 2007, 153, 301–310. With 24 figures ... © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153, 301–310 ... Blackwell Publishing LtdOxford, UKBOJBotanical Journal of the Linnean ...