STUDY OF THE EFFECTS AND INTERACTIONS OF POTASSIUM, CALCIUM AND MAGNESIUM SUPPLY IN POT EXPERIMENTS

LOCH JAKAB¹ – VÁGÓ IMRE^1* – TOLNER LÁSZLÓ² – KISS SZENDILLE¹:

¹University of Debrecen CAS, FA, Department of Agricultural Chemistry

H-4015 Debrecen, P.O. Box: 36. E-mail: Vago@agr.unideb.hu

phone.: +36-52-508-410; fax: +36-52-413-385

²Szent István University, SAES, Department of Soil Science and Agrochemistry

H-2100 Gödöllő, Páter K. u. 1. E-mail: Tolner.Laszlo@mkk.szie.hu

phone.: +36-28-522-000/1807

Introduction

It has been well known from the literature, that some nutrients can modify, help or prevent the uptake and utilization of other nutrients by plants (Bergmann and Neubert, 1976). A typical example of this is the interaction of potassium, calcium and magnesium (Loch, 2000), which is considered generally only from qualitative aspects.

The study of the phenomenon, the quantitative determination of the causative relationships between the measurable parameters can only be performed correctly if the effects and interactions of the several factors are studied in the same experiment.

For the precise study of the treatment effects, it is necessary to apply several doses of the factors, which results in an almost unmanageably high number of treatment combinations when the experiments are planned and implemented in a traditional way. The number of the treatment combinations increases proportionally with the number of factors (k) and the number of treatment levels for the given factor (n): kⁿ. Meaning that if the three treatment factors (potassium, calcium and magnesium) are examined at 5 levels, then the number of treatment combinations is 3⁵ = 125. A further problem is that the treatment combinations should be performed in repetitions, which is indispensable for statistical analyses. When applying the general 4 repetitions, the number of studied elements is 500, which is obviously not or hardly manageable for the performer of the experiment.