Enhancing Root Distribution, Nitrogen, and Water Use Efficiency in Greenhouse Tomato Crops Using Nanobubbles

The aim of this work was to determine the effect of saturating the irrigation solution with air (MNBA) or oxygen nanobubbles (MNBO) on relevant agronomic, productive, and postharvest parameters of tomato crops (Solanum lycopersicum L.) in greenhouses. As a control, conventional management was established, without nanobubbles, under the best possible agronomic conditions used in commercial greenhouses in southeastern Spain. No significant differences were found in the soil properties analysed or in the ionic concentration of the pore water extracted with Rhizon probes. Both MNBA and MNBO modified the root distribution and improved the N uptake efficiency and field water uptake efficiency compared to the control. MNBA had the highest harvest index. The total or marketable production was not affected, although it did increase the overall size of the fruit and the earliness with which they were produced compared to the control. MNBA significantly decreased titratable acidity and soluble solids content compared to the control in the last harvests. Both nanobubble treatments improved postharvest storage under room-temperature (20-25 degrees C) conditions.