The different farming systems had no influence on the incidence of disease, except for fungal pathogens on the leaves, which were reduced by fungicide treatment in the conventional systems. The influence of the annual weather conditions was significant. The amount of fertiliser applied and the previous crop in some cases significantly affected the incidence of fusaria and Microdochium nivale on wheat grains. So the incidence of M. nivale in the organic systems was lower at the higher fertiliser input level. Moreover germination capacity deteriorated with increasing incidence of M. nivale. In 2003, when summer was very dry and hot, a high incidence of Fusarium poae on wheat grains after maize as previous crop was observed. Grain yield in the organic farming systems, where the input of mineral nitrogen was 75% lower, was significantly lower (15 %) than in the conventional farming systems. Hectolitre weight though was not influenced by the farming system. In 1999 and 2002, when part of the wheat plants lodged, and in 2003, a very dry year, the poorer growth of the plants was reflected in the lower yields and smaller, less well-formed wheat grains.
Arbuscular mycorrhizal fungi are important for healthy soils and crops. A pan-European study shows that plant-protection products adversely affect these fungi, reducing their ability to supply plants with phosphorus via their roots.
Birdsfoot trefoil and sainfoin are used in mixtures for perennial hay meadows and for tannin-containing fodder. Agroscope is adding two new cultivars of birdsfoot trefoil to the ‘List of Recommended Varieties of Forage Plants’, whilst there is no change in the case of sainfoin.
Tall oat grass and golden oat grass are typical hay-meadow grasses that are also suitable for forage mixtures. Of the four tall and three golden oat grass varieties tested, only one new variety of tall oat grass is likely to make it onto the List of Recommended Varieties.