A network of experimental fields in northern and western Switzerland was used to better understand the behavior of various cover crops in diversified environmental conditions. Several species were oriented towards soil cover in autumn (e.g. brown mustard). Others produced an important aerial biomass (e.g. sunflower). Some, with intermediate performance during autumn, had a good soil cover at the end of winter, as black oat for example. Multifactorial analysis allowed us to precise the relationship between cover crops performance and environmental and agronomical constraints. We identified positive correlations between soil covering in autumn and the sum of precipitations 10 days before sowing or intermediate tillage before cover crop sowing. Aerial biomass of cover crops at the time of the first frost was correlated with soil texture: lighter soils were more suitable for high aerial development. No species combined all the advantages expected from cover crops all along the fallow period but species mixtures offer the best opportunities.
Spring J.-L-, Zufferey V., Verdenal T., Reynard J.-S., Lorenzini F., Bourdin G., Blouin A., Carlen C., Jermini M., Morisoli R., Ferretti M.
Five Merlot clones bred in Switzerland are currently being distributed by the certification sector. A multiyear trial conducted by Agroscope in Gudo (Canton of Ticino) has made it possible to compare them with French and Italian reference clones and to highlight their very good performances.
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.