Applicability of Variable-Rate Nitrogen Top Dressing Based on Measurement of the Within-Field Variability of Soil Nutrients for Cabbage Production

To improve the efficiency of nitrogen (N) fertilization, it is necessary to perform rapid direct measurements in field rather than time-consuming laboratory-based chemical analysis. Herein, crop and soil data from early stages cabbage growth were acquired through two fall cultivations. Chlorophyll meter value, height, projected leaf area evaluated as indicators. A positive correlation was observed between or its rate increase 2–3 weeks after transplantation head fresh weight (FW). After comparing water-content reflectometers (WCR) a nitrate sensor, we selected WCR with 12 cm-long rod indicator. The diagnostic method verified using varying amounts N basal fertilizer during spring cultivation. variable top dressing (25, 50, 75% total N) based on electrical conductivity (EC) 14 days reduced subsequent EC variability. No differences FW treatments. 25% reduction considered possible for half plots. quantity inorganic extracted by potassium chloride cultivation unaffected amount fertilizer. Therefore, proposed herein suitable management.