In recent years, quality problems in Swiss potato production have increased. In an on-farm experiment on 93 plots all relevant management, site and quality parameters are studied. The results can be summarised as follows: In 2001, only 30% of the plots fulfilled the Swiss quality standard without sorting out damaged tubers. For 19% the quality was even insufficient after sorting out damaged tubers. The proportion of plots with insufficient quality was highest for the organic farming system. In 2001, the most important external quality deficiencies were slug damage, wire worm and dry core. For all of them the position of potatoes in the crop rotation had an important influence. No serious attack of dry core was recorded after a fungicide treatment. An insecticide treatment in the preceding wheat crop could not always reduce wire worm damage sufficiently. A high occurrence of powdery scab was only observed for the variety Agria. No relationship could be found to soil pH. The starch content showed a high variability even within varieties, especially for Bintje and Agria. There was no clear influence of the farming system.
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.