CERZOS   05458
CENTRO DE RECURSOS NATURALES RENOVABLES DE LA ZONA SEMIARIDA
Unidad Ejecutora - UE
artículos
Título:
A comparative study of invasive Helianthus annuus populations in their natural habitats of Argentina and Spain
Autor/es:
POVERENE M.; CANTAMUTTO M.
Revista:
HELIA
Editorial:
Institute of Field and Vegetable Crops
Referencias:
Lugar: Novi Sad; Año: 2010 vol. 33 p. 63 - 74
ISSN:
1018 1806
Resumen:
Wild Helianthus annuus is native to North America but it naturalized in
other parts of the world as well. Although the origin of exotic populations is
uncertain, they have probably evolved very differently in different countries. To
unravel the origin of invasive populations from Argentina and Spain, morphological
and agro-ecological data of nine populations from central Argentina, six
from Andalusia and one from Gerona were collected in their natural habitats
during three exploration trips in 2007 and 2008. In Argentina wild H. annuusHelianthus annuus is native to North America but it naturalized in
other parts of the world as well. Although the origin of exotic populations is
uncertain, they have probably evolved very differently in different countries. To
unravel the origin of invasive populations from Argentina and Spain, morphological
and agro-ecological data of nine populations from central Argentina, six
from Andalusia and one from Gerona were collected in their natural habitats
during three exploration trips in 2007 and 2008. In Argentina wild H. annuusH. annuus
was found mainly in disturbed areas between roads and fences. In a few cases
the populations were located on the margins of cultivated fields. The Argentinean
populations are spread across more than 50,000 m2 at a density of
about 25 plants m-2. In Spain, the populations were found mainly in croplands.
The largest population covered about 1,500 m2 and comprised no more
than 200 plants. The Argentinean populations had taller plants with a higher
number of heads of small size, while the Spanish populations were characterized
by bigger heads with wider ligules and bracts. Plants were shorter and leaf
size was larger in Gerona than in Andalusia. Multivariate analysis differentiated
populations from Argentina and Spain by many traits. Wild-crop gene flow
is likely the source of genetic variation among them. In Argentina, the populations
keep the appearance of early wild introductions, while the Spanish populations
are weedier and probably originated from pollen contamination of
commercial seed with wild plants or crop-wild hybrids.2 at a density of
about 25 plants m-2. In Spain, the populations were found mainly in croplands.
The largest population covered about 1,500 m2 and comprised no more
than 200 plants. The Argentinean populations had taller plants with a higher
number of heads of small size, while the Spanish populations were characterized
by bigger heads with wider ligules and bracts. Plants were shorter and leaf
size was larger in Gerona than in Andalusia. Multivariate analysis differentiated
populations from Argentina and Spain by many traits. Wild-crop gene flow
is likely the source of genetic variation among them. In Argentina, the populations
keep the appearance of early wild introductions, while the Spanish populations
are weedier and probably originated from pollen contamination of
commercial seed with wild plants or crop-wild hybrids.-2. In Spain, the populations were found mainly in croplands.
The largest population covered about 1,500 m2 and comprised no more
than 200 plants. The Argentinean populations had taller plants with a higher
number of heads of small size, while the Spanish populations were characterized
by bigger heads with wider ligules and bracts. Plants were shorter and leaf
size was larger in Gerona than in Andalusia. Multivariate analysis differentiated
populations from Argentina and Spain by many traits. Wild-crop gene flow
is likely the source of genetic variation among them. In Argentina, the populations
keep the appearance of early wild introductions, while the Spanish populations
are weedier and probably originated from pollen contamination of
commercial seed with wild plants or crop-wild hybrids.2 and comprised no more
than 200 plants. The Argentinean populations had taller plants with a higher
number of heads of small size, while the Spanish populations were characterized
by bigger heads with wider ligules and bracts. Plants were shorter and leaf
size was larger in Gerona than in Andalusia. Multivariate analysis differentiated
populations from Argentina and Spain by many traits. Wild-crop gene flow
is likely the source of genetic variation among them. In Argentina, the populations
keep the appearance of early wild introductions, while the Spanish populations
are weedier and probably originated from pollen contamination of
commercial seed with wild plants or crop-wild hybrids.