Faba bean is mostly grown as spring crop in Central Europe; additionally it is grown as winter crop in few mild areas of UK and France. A genetically divers winter bean population selected for high winter hardiness and very promising as winter crop in Germany was studied here. The population was assessed for its agronomic performance as well as for the effect of inbreeding depression due selfing using an open-pollinated generation and two inbred generations developed from it. The assessment was carried out at four environments in two successive seasons (2001 and 2002)
at Goettingen, Central Germany. The open-pollinated population showed better performance in overwintering ability than the UK checks but equivalent performance in yield and other agronomic traits. Winter damage, plant height and yield suffered from inbreeding depression proving heterosis in the open-pollinated generation. Overwintering ability and yield were shown to exhibit a mid parent heterosis of about 32% and of about 75%, respectively. Application of the results in breeding of synthetic cultivars is discussed.
