Chromosome numbers of species of atriplex section obione (chenopodiaceae) and their relation to taxonomy
Por:
Flores-Olvera H., Mercado-Ruaro P.
Publicada:
1 ene 1997
Resumen:
The meiotic chromosome numbers for 18 species of Atriplex section Obione (Chenopodiaceae) are presented. This is the first report for Atriplex abata, A. elegans, A. linifolia, A. minuscula, A. parishii, A. pueblensis, A. tampicensis, A. texana and A. thornberi. Photographs of the meiotic figures of 12 species are presented. All the species are diploid with 2n = 18, except for A triplex argentea, A. cordulata, A. coronata and A. leucophylla tetraploids with 2n = 36. The basic chromosome number (x=9) for the section is confirmed. Atriplex argentea, with the broadest geographic distribution, has at least two ploidy levels. All the tetraploid species occur in southwestern United States, the area of greatest diversity of the section Obione. Chromosome numbers appear to have taxonomic value and allopolyploidy might have played an important role in the evolution of the section.
Filiaciones:
Flores-Olvera H.:
Instituto de Biología, Univ. Nac. Auton. de México, A. P. 70-233, Delegacion Coyoacán, D. F., Mexico
Mercado-Ruaro P.:
Instituto de Biología, Univ. Nac. Auton. de México, A. P. 70-233, Delegacion Coyoacán, D. F., Mexico
All Open Access; Bronze
|