Oxygenation of Irrigation Water during Propagation and Container Production of Bedding Plants

Abstract

<jats:p>Oxygen supply to the root zone is essential for healthy plant growth, and one technology that can potentially supply additional oxygen is the injection of purified oxygen (oxygenation) into irrigation water. The objective was to evaluate whether oxygenation of irrigation water affected plant growth and substrate dissolved oxygen (DO) levels during mist propagation of unrooted cuttings and subsequent growth in containers. Dissolved oxygen measured at source tanks for ambient tap water (averaging 7.1 mg·L<jats:sup>−1</jats:sup>) or oxygenated tap water (31.1 mg·L<jats:sup>−1</jats:sup>) was pumped through fine (69 µm) mist nozzles for propagation of <jats:italic>Calibrachoa</jats:italic> ×<jats:italic>hybrid</jats:italic> ‘Aloha Kona Dark Red’ and <jats:italic>Lobelia erinus</jats:italic> ‘Bella Aqua’. There were no measured differences in root length or root dry mass for <jats:italic>Calibrachoa</jats:italic> and <jats:italic>Lobelia</jats:italic> propagated using oxygenated water compared with ambient water because DO of ambient or oxygenated water reached ≈100% oxygen saturation in water (8.7 mg·L<jats:sup>−1</jats:sup>) after passing through mist nozzles. To evaluate subsequent growth without the effect on DO of fine emitters, rooted cuttings of these two plant species and <jats:italic>Pelargonium</jats:italic> ×<jats:italic>hortorum</jats:italic> ‘Patriot Red’ were grown in 10.2-cm diameter pots. The plants were irrigated with either ambient (6.0 mg·L<jats:sup>−1</jats:sup>) or oxygenated (27.7 mg·L<jats:sup>−1</jats:sup>) nutrient solutions, delivered by top watering or subirrigation when the substrate dried to ≈45% of container capacity (CC), measured gravimetrically. Oxygenated water did not enhance root or shoot growth compared with ambient water for the three bedding plants. In addition, <jats:italic>Pelargonium</jats:italic> growth was not enhanced when irrigated at high moisture level (maintained at 80% CC) with oxygenated water compared with ambient water. In container substrate without plants, it was possible to increase DO of the substrate solution by 68% when a high volume of oxygenated water (200% container volume or 850 mL) was applied by top watering because existing substrate solution was displaced. In contrast, when containers were subirrigated at 45% CC, the smaller 180-mL volume of oxygenated water was absorbed by the substrate and did not increase DO compared with ambient water. Overall, irrigating with oxygenated water did not enhance root or plant growth of three bedding plants grown in porous, peat-based substrate. To increase oxygen supply to roots in container production, growers should focus on having adequate air porosity in substrate and avoiding overwatering.</jats:p>

Assessment of the Quality of Well Dug Water Samples in Nigeria and Their Suitability for Drinking and Irrigation Purposes

“…When there is less water in the water than there is in the root, the permeability of the roots to water decreases, and the absorption of nutrients decreases (or even reverses). Irrigation water that has been oxygenated has been shown to increase plant biomass in some studies (Yafuso and Fisher, 2017).…”

Water quality analysis of old and new Phuleli Canal for irrigation purpose in the vicinity of Hyderabad, Pakistan

“…The reason may be the activities of microbes were decreased such as Ammonia Oxidizing Bacteria (AOB) (Keerio & Bae 2020;Keerio et al 2020a). However, regarding the plant and crops DO between 3.5 to 6.5 mg/L is sufficient for high corn yield (Yafuso & Fisher 2017).…”

“…Oxygen supply to the root zone is important for plant health. Irrigating plants with two aeration systems oxygenated with DO from 3.5 to 6.5 mg/L, resulting in higher corn yield and biomass as compared with grown with low DO water 0.3-4.5 mg/L (Yafuso & Fisher 2017). DO in water can cause the microbial reduction as nitrate to nitrite and sulfate to sulfide.…”

Renewable Energy Integration Into Cloud & IoT-Based Smart Agriculture

“…• Advantages: -Collecting rainwater: by collecting rainwater, water table resources are saved, and energy use is reduced. -Improving water quality: when water is kept in basins, it becomes more oxygenated, thus becoming more beneficial for the plants [49]. • Drawbacks:…”