Orobanche rameuse (Orobanche ramosa L.) du colza : un risque émergent sous surveillance

¹ Laboratoire de parasitologie végétale, case courrier 155, Université Pierre et Marie Curie, 4 Place Jussieu, 75252 Paris cedex 05, France
² CETIOM, Direction scientifique, BP n°4, 78850 Thiverval-Grignon France

^* pinochet@cetiom.fr

Reçu : 21 Juillet 2005
Accepté : 21 Février 2006

Abstract

Broomrapes are parasitic plants without chlorophyll, nutritionally depending from their host plant. Orobanche ramosa L. is a parasite of numerous plants including winter oilseed rape. Its presence has been reported for a long time in the South of France. Nevertheless, its presence became a major problem in the Central West region Poitou-Charentes since the middle of the nineties. The phenomenon is under observation, and research work has been undertaken to evaluate its extension risks and to propose efficient solutions. The main extension factors are its ability to produce seeds, its wide ability to germinate in different environmental conditions, its large number of potential host plants, including common weeds present in cropped fields. Short term recommendations intend to favour the host in the nutritional competition and to limit the soil seed bank. For a longer term, several possibilities could be carried out : optimization of false hosts/trap-crops introduction in the rotation which could decrease the soil seed bank ; and breeding for herbicide resistant plants through mutagenesis or genetic transformation.