Location: Water Management and Conservation Research
Project Number: 2020-13660-009-016-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: May 1, 2025
End Date: Apr 30, 2027
Objective:
Evaluate the potential of nanobubble-enriched irrigation to enhance crop productivity and WUE in both soil-based and hydroponic systems. Specifically, we seek to determine whether the sustained delivery of different gases as nanobubbles can significantly improve early-stage plant growth, biomass production, and increase the “crop per drop” ratio under water-limited and saline conditions. The proposed research will focus on two complementary systems:
1) turf grass grown in saline soil to assess the resilience and efficiency of NB irrigation in conventional agriculture;
2) lettuce grown in hydroponic systems to explore how NBs influence plant physiology, nutrient uptake, and root-associated microbial activity in soilless environments.
Approach:
We aim to test how nanobubbles of different gases (O2, CO2, N2, and air) can improve crop yield, plant physiology, and microbial activity, particularly under water-stressed conditions.
1. Hydroponic Lettuce Cultivation
Lettuce (Lactuca sativa) will be grown in mid-scale hydroponic systems greenhouse supplied with nutrient solution and enriched with nanobubbles of either O2, CO2, or N2, generated using a Gaia Water NB generator. Control systems without NBs will also be included. Plants will be grown under controlled greenhouse conditions, and performance will be monitored over a 4-to-6-week period.
Key metrics will include:
• Growth parameters: biomass (fresh and dry), number of leaves, stem/root length.
• Photosynthetic performance: chlorophyll content (SPAD), FPSII, Fv/Fm, and rETR using a Mini-PAM II system.
• NB stability: pH, DO, N-species, NB size and concentration over time using NTA and zeta potential analysis.
2. Turfgrass Irrigation in Saline Conditions
Turfgrass will be grown in sandy-loam soil with elevated salinity levels to simulate arid environments. Plots will be irrigated with either control water or water enriched with nanobubbles (O2, CO2, or N2) using water with different ionic strength. Growth performance and stress indicators will be monitored during the entire growth cycle:
• Growth assessment: shoot density, root length, turf greenness (NDVI), and biomass.
• Stress indicators: antioxidant enzyme activity (catalase, ascorbic peroxidase), leaf sodium accumulation, and visual stress scoring.
• Soil microbiome activity: root-associated bacterial growth and biofilm formation via microscopy and sequencing.
This two-pronged approach will allow us to evaluate the benefits of NB irrigation under both soil-based and hydroponic systems, addressing the need for resilient and efficient crop production technologies in water-limited environments.