The split-root technique is a promising system for cultivating plants under saline conditions, facilitating the production of salt-sensitive vegetables in saline aquaponics . While saline aquaponics typically uses salt-tolerant plants due to high salinity levels, these plants have not yet reached consumer acceptance. Integrating high-value vegetables like red kale could significantly enhance economic feasibility. Split-root enables a plant to have m ore than one root zone environment, which is crucial for nutrient and water uptake under salinity stress. The system allows direct use of shrimp aquaculture effluents at high salinity levels, without dilution, avoiding reduced nutrient concentrations for plants.
Despite its potential, there is a lack of studies on split-root application in Deep Water Culture (DWC), a prevalent aquaponics system. Thus, a study was conducted to evaluate the split-root system in managing salinity stress in red kale within a DWC aquaponics setup based on shrimp effluent. The experiment encompassed a completely randomized design with three treatments: Hydroponics at 0 parts per thousand (ppt), Saline Hydroponics at 10 ppt , and Shrimp effluent at 10 ppt. Two split-root conditions, homogeneous and heterogeneous, were used to create different root environments.
The results of the ANOVA showed significant interactions (p<0.05) among the conditions and salinity levels for size index, biomass accumulation, and plant height. Heterogeneous conditions demonstrated higher performance at 10 ppt salinity compared to homogeneous conditions and there were no significant differences (p>0.05) between the saline hydroponics and the shrimp effluent treatments. However, in photosynthesis measurements and tissue analysis, no interactions were found between conditions, but there were significant differences among the salinity levels. Hydroponics (0 ppt) was significantly different (p<0.05) from the rest of the treatments under both the homogenous and heterogenous conditions, whereas saline hydroponics and shrimp effluent did not show significant differences (p>0.05). Th e study highlights the effect of the split-root heterogeneous condition in managing salinity stress in red kale , offering valuable insights into optimizing plant growth under saline conditions while showing potential opportunities for further research.