INVESTIGADORES
BRUGNOLI Elsa Andrea
artículos
Título:
Diversity in Apomictic Populations of Paspalum simplex Morong
Autor/es:
BRUGNOLI, ELSA ANDREA; URBANI, MARIO HUGO; QUARÍN, CAMILO LUIS; ZILLI, ALEX LEONEL; MARTÍNEZ, ERIC JAVIER; ACUÑA, CARLOS ALBERTO
Revista:
CROP SCIENCE
Editorial:
CROP SCIENCE SOC AMER
Referencias:
Lugar: Baltimore; Año: 2014 vol. 54 p. 1656 - 1664
ISSN:
0011-183X
Resumen:
Paspalum is considered a genetic model for
studying the sources of genotypic variability and
breeding techniques in apomictic plants. Paspalum
simplex is a warm-season forage grass
that well represents the genus since it contains
different ploidy levels and apomixis is linked to
polyploidy. The objective was to evaluate the
diversity present within and among apomictic
polyploid populations of P. simplex. Germplasm
was collected from 17 sites covering the species?
region of natural distribution. The diversity
present at the molecular level within and among
populations was evaluated using ISSR markers.
Variability for agronomic traits was also evaluated
by cultivating all populations into the field.
The 17 analyzed populations were all polyploid,
including 13 pure tetraploid, and 4 mixed tetraploid-
hexaploid with predominance of the tetraploid
cytotype. Most of the diversity was present
among polyploid populations (85% of the
total variation), and there was not a correlation
between genetic and geographical distances.
The within-population diversity was low for most
populations with the exception of one of them.
Each genotype was restricted to a single location.
Variability for initial growth, spring and fall
growth, and the extent of the vegetative phase
was observed within and among polyploid populations.
The within-population variation for these
phenotypic traits was mainly due to the presence
of one or a few off-type plants. A highly genotype-
specific colonization of new sites appears
to occur in P. simplex, and then apomixis mediates
the formation of uniform populations