01728naa a2200229 a 450000100080000000500110000800800410001910000190006024500510007926000090013052011300013965000160126965000170128565000180130265000150132065300170133565300210135270000150137370000250138870000220141377300630143511325312018-04-30       1997    bl uuuu     u00u1 u    #d1 aMELO, N. F. de  aCytogenetics and cytotaxonomy of Velloziaceae.  c1997  aChromosome number and other cytological features are reported from 35 species of Velloziaceae, including several african and brazilian populations. All analyzed species show areticulate interphase nuclei and prophase/prometaphase chromosomes with proximal early condensation. Most heteropycnotic blocks do not seem to correspond to heterochromatin since, at least in Vellozia patens, they do not stain differentially after C-banding procedures. Regarding the chromosome number, three main groups could be identified. The first comprised diploid species of the genera Nanuza, Vellozia and the brazilian species of Xerophyta with 2n=14 or 16; the second comprised tetraploid species with 2n=34, and included all brazilian species of subfam. Barbacenioideae; the third group, of hexaploid species, comprised the African representatives of the genus Xerophyta. A single population of Vellozia, possibly of hybrid origin, had 2n~=32. A basic number of x=8 is proposed for the family. The karyological information supports the hypothesis that the Velloziaceae originated on the South American, rather than on the African continent.  achromosomes  aVelloziaceae  aCitotaxonomia  aCromossoma  aCytotaxonomy  aHeterochromation1 aGUERRA, M.1 aBENKO-ISEPPON, A. M.1 aMENEZES, N. L. de  tPlant Systematics and Evolutiongv. 204, p. 257-273, 1997.