The prudence exercised in removing residual aqueous ozone
from treated irrigation solutions prior to distribution to the crop
is not justified in terms of potential negative impacts on plant productivity
when using drip style irrigation systems. On the contrary,
this study supports the conclusion that low to moderate residual
ozone concentrations (those used in this study) applied directly to a
mineral fibre growth substrate improves several key tomato performance
metrics. In no instance was the ozone treatment detrimental
to productivity. The benefits of retaining a residual ozone concentration
during distribution to the crop in terms of irrigation system
maintenance and hygiene as well as water use efficiency can now
be realized in drip hydroponic tomato culture