Preventing botanical contamination risk of sunflower hybrid seed in the Valle Bonaerense del Río Colorado, Argentina

CANTAMUTTO M, PRESOTTO A, RENZI JP, POVERENE M.

Proceedings of 17th Intern. Sunflower Conference

International Sunflower Association

Lugar: Cordoba, Spain; Año: 2008; p. 697 - 702

River Colorado Valley in southern Buenos Aires province (VBRC) is the main sunflower seed production area in Argentina, with over 8000 hectares, standing for 85% of the controlled fields over the country. The wild annual species Helianthus annuus and H. petiolaris naturalized in Argentina can pollinate crop plants giving fertile progeny. As in the US and in Europe, the presence of these species limits seed production because they represent a contaminating pollen source. However, at present none of them have invaded the VBRC area. An ecological characterization was performed in order to assess the invasiveness of the VBRC. To test agro-ecological dissimilarity, habitats of both wild species in Argentina and the center of origin were compared using macro-abiotic (climatic and soil taxa), micro-abiotic (soil composition), and biotic (plant community) variables. Ecological conditions were found not to be restraining for the establishment of wild Helianthus invaders in the VBRC. An active alertness was initiated, comprising an exhaustive cleaning of machinery coming from other regions, roguing for off-type plants within seed production fields, to avoid annual Helianthus species culture for ornamental purposes, and removal of all feral forms of annual Helianthus within the protected region. Helianthus annuus and H. petiolaris naturalized in Argentina can pollinate crop plants giving fertile progeny. As in the US and in Europe, the presence of these species limits seed production because they represent a contaminating pollen source. However, at present none of them have invaded the VBRC area. An ecological characterization was performed in order to assess the invasiveness of the VBRC. To test agro-ecological dissimilarity, habitats of both wild species in Argentina and the center of origin were compared using macro-abiotic (climatic and soil taxa), micro-abiotic (soil composition), and biotic (plant community) variables. Ecological conditions were found not to be restraining for the establishment of wild Helianthus invaders in the VBRC. An active alertness was initiated, comprising an exhaustive cleaning of machinery coming from other regions, roguing for off-type plants within seed production fields, to avoid annual Helianthus species culture for ornamental purposes, and removal of all feral forms of annual Helianthus within the protected region.