Chromosome Reports in South American Nicotianeae (solanaceae), with Particular Reference to Nierembergia
نویسندگان
چکیده
Chromosome counts and karyotype information from 41 populations of 20 species and 6 varieties of Nicotianeae (Solanaceae) from South America belonging to Bouchetia Dunal (x 5 8), Fabiana Ruiz & Pav. (x 5 9), Leptoglossis Benth. (x 5 10), Nierembergia Ruiz & Pav. (x 5 8, 9), and Petunia Juss. (x 5 7, 9) are given, including first reports from 14 taxa: F. densa Rémy, N. ericoides Miers, and P. patagonica (Speg.) Millán, with 2n 5 2x 5 18, and N. browallioides Griseb., N. calycina Hook., N. graveolens A. St.-Hil., N. linariifolia Graham var. glabriuscula (Dunal) A. A. Cocucci & Hunz., var. pampeana (Millán) A. A. Cocucci & Hunz., and var. pinifolioides (Millán) A. A. Cocucci & Hunz., N. pulchella Miers var. pulchella and var. macrocalyx (Millán) A. A. Cocucci & Hunz., N. rivularis Miers, N. tucumanensis Millán, and N. veitchii Hook., with 2n 5 2x 5 16. All species studied are diploids, and most have 2n 5 16. In addition, infraspecific polyploidy is recorded for the first time in N. rigida Miers (2n 5 4x 5 32) and confirmed in N. aristata D. Don (n 5 3x 5 24, 2n 5 6x 5 48). In general, karyotypes of the examined species are symmetrical and composed of comparatively small and uniformly sized chromosomes, mostly of the metacentric (m) type except in L. linifolia (Miers) Griseb., P. axillaris (Lam.) Britton, Stern & Poggenb., and P. patagonica, where submetacentric (sm) chromosomes are predominant. There are one or, rarely, two chromosomes bearing nucleolar organizing regions per basic complement. In Nierembergia, karyotype data reflect species grouping. Results suggest that Bouchetia is the closest taxon to Nierembergia, while Leptoglossis, Petunia, and Fabiana appear more distant. Possible chromosome number evolution in the tribe is speculated based on molecular phylogenetic studies by other authors. In Nierembergia, x 5 9 is proposed to be derived from x 5 8. Dysploid changes in chromosome number and conservation of chromosome morphology in the karyotypes appear as important evolutionary events in the tribe, while polyploidy is noteworthy only in Nicotiana L.
منابع مشابه
Variation of pollinator assemblages and pollen limitation in a locally specialized system: the oil-producing Nierembergia linariifolia (Solanaceae).
BACKGROUND AND AIMS Few studies have examined the dynamics of specialist plant-pollinator interactions at a geographical scale. This knowledge is crucial for a more general evolutionary and ecological understanding of specialized plant-pollinator systems. In the present study, variations in pollinator activity, assemblage composition and pollen limitation were explored in the oil-producing spec...
متن کاملNeurotoxicity in calves induced by the plant, Nierembergia hippomanica Miers var. violacea Millán in South Africa.
The plant Nierembergia hippomanica var. violacea has been incriminated in field outbreaks of neurotoxicity in calves in the Free State Province. Hepatotoxicity and electrocardiogram (ECG) deviations were induced in a sheep dosed with 5 g/kg dried plant material on four consecutive days. A calf dosed with 2.5 g/kg dried plant material, on two consecutive days, did not show overt clinical changes...
متن کاملDiversity and distribution patterns of Solanaceae in Iran: Implications for conservation and habitat management with emphasis on endemism and diversity in SW Asia
The increasing rate of irreversible damages to natural habitats has reinforced the need for gathering biodiversity fundamental data to conservation. Priority setting is the most important step in protection programs. Solanaceae as the the one of important economic families of eudicots distributed throughout North and South America, Europe, Africa, Asia, Australia, and the South Pacific. Up to n...
متن کاملKaryotype differentiation of four Cestrum species (Solanaceae) revealed by fluorescent chromosome banding and FISH
The karyotypes of four South American species of Cestrum (C. capsulare,C. corymbosum,C. laevigatum and C. megalophylum) were studied using conventional staining, C-CMA/DAPI chromosome banding and FISH with 45S and 5S rDNA probes. The karyotypes showed a chromosome number of 2n = 2x = 16, with metacentric chromosomes, except for the eighth submeta- to acrocentric pair. Several types of heterochr...
متن کاملPartial and complete microdeletions of Y chromosome in infertile males from South of Iran
Y chromosome microdeletions are the second genetic cause of male infertility. The incidence of Y chromosome microdeletions can vary considerably depending on several factors, including patient selection criteria, population composition, and diagnostic protocols. They are associated with spermatogenic failure and lead to azoospermia or oligozoospermia. The advance in assisted reproductive techno...
متن کامل