NITROGEN SUPPLY OF VEGETABLES BASED ON THE “KNS-SYSTEM”

This paper reviews 12 years experience of experiments and farm practice with the very flexible N_min target values system named KNS, which is described in full detail.
The acceptance of this system by the vegetable growers in the Pfalz area of Germany is based on the provision of rapid soil sampling and fertilizer recommendations.
Demand for this system has consistently increased since its introduction and a very high percentage of the vegetable fields are now checked by Nmin-soil analysis before fertilizing.
The average savings of nitrogen fertilizer amount to about 50% of that used before the introduction of KNS. In some cases there are still problems with high N_min residues which have important implications for controlled integrated crop production.
It is shown that nitrogen applications for insurance reasons are decreasing with growing experience in farm practice, but high residues can be a problem with the second crop in the year.
The influence of the crop rotation offers further possibilities to reduce N_min residues.

Ecological aspects of Vegetable Fertigation in Integrated crop Production in the Field

J. Ziegler, K. Strohmeier, T. Brand

nitrogen recommendation system, fertilizing system, N_min residues, soil samples, N-buffer, N-uptake

https://doi.org/10.17660/ActaHortic.1996.428.23