THE EFFECT OF IRRIGATION WATER QUALITY ON THE GROWING MEDIUM

This report presents results of greenhouse evaluations of the effect of Na, Cl, HCO₃, F, B, Cd, Cu, Mn, Zn, Al and Pb, present in irrigation water, on the growing medium (peat, coniferous litter or a 1:1 mix of coniferous litter and oak leaf mould) and on ornamental plants.

The influence of various chemical constituents of irrigation water and their associated potential hazards with regard to the substrate and to plant growth could be divided eighter in salinity effects, due to substances contributing to the total osmotic pressure of the soil solution (Na, Cl, HCO₃), or specific ion effects of solutes of a nutritional nature (F, B, heavy metals), becoming toxic above a certain concentration.

The element contents of substrate extracts and plant leaves were analyzed for diagnostic interpretation.
Except for HCO₃, all ions accumulated in the substrate.
Treatments were also well reflected in the foliage of test plants, subsequent to uptake by roots.

Based on this work and on the litterature, guidelines for interpretation of quality of water for irrigation, are given.

Symposium on Production of Protected Crops in Peat and other Media

R. Gabriëls

https://doi.org/10.17660/ActaHortic.1978.82.27