INVESTIGADORES
SEIJO jose guillermo
artículos
Título:
Karyotype analysis and chromosome evolution in South American species of Lathyrus (Leguminosae)
Autor/es:
JOSE GUILLERMO SEIJO; FERNANDEZ, A.
Revista:
AMERICAN JOURNAL OF BOTANY
Editorial:
BOTANICAL SOC AMER INC
Referencias:
Año: 2003 vol. 90 p. 980 - 987
ISSN:
0002-9122
Resumen:
The karyotypes of 10 species and one variety of South American Lathyrus were determined and compared with those obtained of
five entities from the Northern Hemisphere. Although all the species have a chromosome number of 2n 5 14, they could be differentiated
by their karyotype formula and quantitative parameters of the karyotypes. Phenetic distance and principal component analysis
showed that in spite of the differences observed among entities, they can be grouped in clusters that coincide with the taxonomic
sections established by F. K. Kupicha and with the life cycle of the species. South American species form a homogeneous group and
can be distinguished by the presence of a subtelocentric pair, which has a macrosatellite in the long arm, and the lack of a short
metacentric pair characteristic of most species of the Northern Hemisphere. From an evolutionary point of view, variation in total
chromosome length without major changes in the karyotype formula suggests that changes in the amounts of genomic DNA are
proportional to the relative length of each chromosome arm and that species of Notolathyrus evolved in a concerted fashion. Variation
in genome size, however, is congruent with morphological variation of some reproductive organs as well as with the life cycle and
minimum generation time, as predicted by the nucleotype hypothesis.