Residual Effects of Legumes in Wheat-Based Cropping Systems in a Temperate Environment

Sustainable agricultural systems preserve soil quality and biodiversity through an appropriate croprotation. In Southern Europe's environments, non-irrigated agricultural systems depend on wintercrops; with limited alternatives, farmers rely on short rotations of wheat and barley. One way toimprove the sustainability of these systems is to introduce legume crops such as faba bean and fieldpeas into the rotation. These species play beneficial effects including increased soil organic mattercontent, reduced incidence of root and leaf diseasesi n subsequentc rops, reduced weed populations(Blackshawe t al.,1994), increasedP , K and S availability (Bullock, 1992),improved soil structurea ndstability (Karle et al., 1994). Overall they may represent an altemative to commercial nitrogenfertilizers and provide a net input to soil N, particularly important in organic farming systems.This work is aimed at investigating on the residual effect on wheat of two legume species (faba beanand freld peas) at two different sowing time (autumn and winter) in a biannual rotation system wheatpulsecrops[...]