CERZOS   05458
CENTRO DE RECURSOS NATURALES RENOVABLES DE LA ZONA SEMIARIDA
Unidad Ejecutora - UE
artículos
Título:
Ecological characterization of wild Helianthus annuus and H. petiolaris germplasm in Argentina.
Autor/es:
M. POVERENE, M. CANTAMUTTO, G.J. SEILER
Revista:
Plant Genetic Resources Characterization and Utilization
Editorial:
CropGen International, UK
Referencias:
Año: 2008 vol. 7 p. 42 - 49
Resumen:
Abstract
Helianthus annuus and H. petiolaris (Asteraceae) are wild sunflowers native to North America
but have become naturalized in central Argentina covering an area of about 5 million hectares.
Wild H. annuus has been recognized as invader species in several countries, but no research
has been done to study the ecological determinants of their distribution. In a survey covering
seven provinces between 318580 388S and 608330 698W, we described the ecology of the main
wild populations. Wild Helianthus populations were located in three of the 18 ecological
regions of Argentina, on five Mollisol and seven Entisol soil groups. The associated plant communities
were comprised 60 species belonging to 16 families, all being frequent components
of the native flora. Disease symptoms were seldom observed in wild populations, with Alternaria
helianthi being the most commonly observed pathogen. Population size varied from less
than 100 to more than 100,000 plants, covering from 100 to more than 60,000m2 with densities
most frequently up to 3 plants/m2, but reaching 80 plants/m2 at certain sites. Intermediate plant
phenotypes between wild species and cultivated sunflower were found in one-third of the
populations providing evidence of intense gene flow. Hybrid swarms were found at three
localities with population sizes between 100 and 10,000 individuals.and H. petiolaris (Asteraceae) are wild sunflowers native to North America
but have become naturalized in central Argentina covering an area of about 5 million hectares.
Wild H. annuus has been recognized as invader species in several countries, but no research
has been done to study the ecological determinants of their distribution. In a survey covering
seven provinces between 318580 388S and 608330 698W, we described the ecology of the main
wild populations. Wild Helianthus populations were located in three of the 18 ecological
regions of Argentina, on five Mollisol and seven Entisol soil groups. The associated plant communities
were comprised 60 species belonging to 16 families, all being frequent components
of the native flora. Disease symptoms were seldom observed in wild populations, with Alternaria
helianthi being the most commonly observed pathogen. Population size varied from less
than 100 to more than 100,000 plants, covering from 100 to more than 60,000m2 with densities
most frequently up to 3 plants/m2, but reaching 80 plants/m2 at certain sites. Intermediate plant
phenotypes between wild species and cultivated sunflower were found in one-third of the
populations providing evidence of intense gene flow. Hybrid swarms were found at three
localities with population sizes between 100 and 10,000 individuals.H. annuus has been recognized as invader species in several countries, but no research
has been done to study the ecological determinants of their distribution. In a survey covering
seven provinces between 318580 388S and 608330 698W, we described the ecology of the main
wild populations. Wild Helianthus populations were located in three of the 18 ecological
regions of Argentina, on five Mollisol and seven Entisol soil groups. The associated plant communities
were comprised 60 species belonging to 16 families, all being frequent components
of the native flora. Disease symptoms were seldom observed in wild populations, with Alternaria
helianthi being the most commonly observed pathogen. Population size varied from less
than 100 to more than 100,000 plants, covering from 100 to more than 60,000m2 with densities
most frequently up to 3 plants/m2, but reaching 80 plants/m2 at certain sites. Intermediate plant
phenotypes between wild species and cultivated sunflower were found in one-third of the
populations providing evidence of intense gene flow. Hybrid swarms were found at three
localities with population sizes between 100 and 10,000 individuals.8580 388S and 608330 698W, we described the ecology of the main
wild populations. Wild Helianthus populations were located in three of the 18 ecological
regions of Argentina, on five Mollisol and seven Entisol soil groups. The associated plant communities
were comprised 60 species belonging to 16 families, all being frequent components
of the native flora. Disease symptoms were seldom observed in wild populations, with Alternaria
helianthi being the most commonly observed pathogen. Population size varied from less
than 100 to more than 100,000 plants, covering from 100 to more than 60,000m2 with densities
most frequently up to 3 plants/m2, but reaching 80 plants/m2 at certain sites. Intermediate plant
phenotypes between wild species and cultivated sunflower were found in one-third of the
populations providing evidence of intense gene flow. Hybrid swarms were found at three
localities with population sizes between 100 and 10,000 individuals.Helianthus populations were located in three of the 18 ecological
regions of Argentina, on five Mollisol and seven Entisol soil groups. The associated plant communities
were comprised 60 species belonging to 16 families, all being frequent components
of the native flora. Disease symptoms were seldom observed in wild populations, with Alternaria
helianthi being the most commonly observed pathogen. Population size varied from less
than 100 to more than 100,000 plants, covering from 100 to more than 60,000m2 with densities
most frequently up to 3 plants/m2, but reaching 80 plants/m2 at certain sites. Intermediate plant
phenotypes between wild species and cultivated sunflower were found in one-third of the
populations providing evidence of intense gene flow. Hybrid swarms were found at three
localities with population sizes between 100 and 10,000 individuals.Alternaria
helianthi being the most commonly observed pathogen. Population size varied from less
than 100 to more than 100,000 plants, covering from 100 to more than 60,000m2 with densities
most frequently up to 3 plants/m2, but reaching 80 plants/m2 at certain sites. Intermediate plant
phenotypes between wild species and cultivated sunflower were found in one-third of the
populations providing evidence of intense gene flow. Hybrid swarms were found at three
localities with population sizes between 100 and 10,000 individuals.being the most commonly observed pathogen. Population size varied from less
than 100 to more than 100,000 plants, covering from 100 to more than 60,000m2 with densities
most frequently up to 3 plants/m2, but reaching 80 plants/m2 at certain sites. Intermediate plant
phenotypes between wild species and cultivated sunflower were found in one-third of the
populations providing evidence of intense gene flow. Hybrid swarms were found at three
localities with population sizes between 100 and 10,000 individuals.2 with densities
most frequently up to 3 plants/m2, but reaching 80 plants/m2 at certain sites. Intermediate plant
phenotypes between wild species and cultivated sunflower were found in one-third of the
populations providing evidence of intense gene flow. Hybrid swarms were found at three
localities with population sizes between 100 and 10,000 individuals.2, but reaching 80 plants/m2 at certain sites. Intermediate plant
phenotypes between wild species and cultivated sunflower were found in one-third of the
populations providing evidence of intense gene flow. Hybrid swarms were found at three
localities with population sizes between 100 and 10,000 individuals.