M. Mijas, O. Nowosielski
The present investigations were based on field experiments carried out in 1966–1968 with increasing nitrogen fertilization levels.

For the investigations vegetables with different nitrogen requirements, viz.: late cabbage and cucumber, were selected The nitrogen fertilizer rates, from 0 to 900 kg N/ha, were applied against a uniformly high phosphorus-potassium fertilization level. In the growing season plant and soil samples were taken with the purpose of:

  1. establishing the indicative part of the given plant ilustrating most exactly nitrogen nutrition degree;
  2. determining the range of the indicative nitrogen form content in the growing season depending on the nitrogen fertilization level;
  3. determining critical levels of mineral nitrogen in the soil.

It has been assumed that the nitrogen nutrition status of plants will be estimated by means of analyzing plants for N-NO3 content and soil for nitrate and ammonium nitrogen content in arable layer.

N-NO3 was determined in air-dry matter of plants and in dry soil using the methods with brucine (soil and cucumbers) or brucine and phenol-disulphonic acid application (cabbage). N-NH4 in soil was determined using the Nessler's reagent.

The investigations have shown that:

  1. This selection has been made on a basis of the
Mijas, M. and Nowosielski, O. (1973). INVESTIGATIONS ON NITROGEN NUTRITION INDICES OF CABBAGE AND CUCUMBER. Acta Hortic. 29, 101-104
DOI: 10.17660/ActaHortic.1973.29.6

Acta Horticulturae