This paper explains the principle of economically optimal N-fertilisation (Nopt). This principle allows the quantitative derivation of N-fertilisation standards based on N-fertilisation trials. The optimum level of N-fertilisation thus found represents a good compromise between the economic and ecological aims of arable farming. Within the framework of the ‘Principles of Fertilisation in Arable and Forage-Crop Production’ (GRUDAF) 2009 studies, the Nopt for several important arable crops was determined based on extensive N- fertilisation trials. For all crops but maize, the results of these studies have led to an increase in optimum N-fertilisation by 10 to 40 kg N ha-1. In order to promote N-fertilisation adapted to site productivity, however, the N- fertilisation standards of these crops were not as a rule raised, but rather yield-dependent correction factors were introduced for the N-quantities to be applied.
Stucky T., Hochstrasser M., Meyer S., Segessemann T., Ruthes A. C., Ahrens C. H., Dahlin P., Pelludat C.
The root knot nematode (RKN) Meloidogyne incognita causes damage in field and greenhouse crops. Agroscope researchers have developed a new screening test to identify bacteria that antagonise this agricultural pest.
With CULTAN fertilisation, nitrogen is injected into the soil as an ammonium solution. Multi-year trials conducted by Agroscope show that this method reduces nitrogen leaching by an average 38% without negatively affecting yields.
Tuta absoluta is one of the most destructive pests of solanaceous crops. Agroscope has developed a statistical model to study the population dynamics of the pest and its parasitoids and allows interventions to be optimally planned.