Chromosome studies of some species ofVernonanthuraandVernonia(Asteraceae, Vernonieae)

Abstract

The chromosome numbers of 18 populations belonging to 10 species of Vernonanthura H. Rob. and one species of Vernonia Schreb. (Vernonieae, Asteraceae) from South America were determined. Vernonia echioides (n = 34) are in agreement with previous records for these species. All the species of Vernonanthura and Vernonia analyzed here showed basic number x 2 = 17 and almost all them were diploid with 2n = 34. The single exception was Vernonia echioides which showed diploid (2n = 34) and tetraploid (2n = 68) populations.

Cytogenetic characterization ofSchinus terebinthifoliusRaddi (Anacardiaceae) accessions from Rio Grande do Sul State, Brazil

“…In studies of the family Asteraceae, due to the large variability in chromosome number and lack of cytological data, Vega and Dematteis (2012) determined the numbers of Vernonanthura and Vernonia. It was the first chromosome count for Vernonanthura lucida (Less.)…”

Cytotaxonomy of some species ofVernonanthuraandVernonia(Asteraceae, Vernonieae) from South America

“…The chromosome morphology was determined using the centromeric Vernonia (Hunter 1964;Jones 1979Jones , 1982Galiano and Hunziker 1987;Stutts 1988;Ruas et al 1991;Dematteis 1996Dematteis , 1997Dematteis , 2002Dematteis and Fernández 1998;Salles de Melo et al 2010;Oliveira et al 2007). The single analysis after the genus segregation reported chromosome numbers of 15 populations belonging to 10 taxa of Vernonanthura (Vega and Dematteis 2012). In this study, first chromosome counts were presented for three taxa: V. lucida (n = 17II, 2n = 34); V. oligactoides (n = 17II, 2n = 34) and V. pseudolinearifolia (2n = 34).…”

“…str. has only two South American species, V. incana, which is always diploid with 2n = 2x = 34, and V. echioides with diploid and tetraploid cytotypes (Vega and Dematteis 2012).…”

“…The ideograms and chromosome measures were estimated from 10 metaphases plates of 7-10 individuals per species. The karyotypes of V. loretensis (2n = 34), V. lucida (2n = 34), V. nudiflora (2n = 34), V. oligactoides (2n = 34), V. pseudolinearifolia (2n = 34), V. squamulosa (2n = 34), and V. tweediana (2n = 34) were carried out from a population analyzed by Vega and Dematteis (2012).…”

“…Chromosome numbers have not been utilized in the proposed classification and less than 20% of the species from the New World have been analyzed (Dematteis 2002). However, the cytological data from South America Vernonieae show that chromosomes are widely variable 1998; Carr et al 1999;v2007;Salles de Melo et al 2010;Vega and Dematteis 2012).…”