Coriander cultivation under different nutrient solution depths in hydroponic systems: a comparison between conventional DFT and adapted DFT with PVC pipes

Due to the water scarcity in arid and semi-arid regions, hydroponic cultivation can be an alternative for these areas since it requires less water than traditional cultivation systems. Thus, this study aimed to evaluate the growth, production, water consumption, water use efficiency, and visual quality of coriander using the Deep Flow Technique (DFT) under different nutrient solution depths. We conducted two experiments concurrently in an entirely randomized block design and a factorial arrangement in a split plot. In the main plots, we evaluated two nutrient solution depths (0.02 and 0.03 m in the hydroponic channel of the adapted DFT system with PVC pipes) and three solution depths (0.013, 0.017, and 0.025 m in wooden tanks of the conventional DFT system), with two coriander cultivars (Tabocas and Verdao) in the sub-plots. At 20 and 25 days after transplanting following variables were determined: plant height, water content in the shoot, shoot fresh matter, shoot dry matter, water consumption, and water use efficiency. In general, coriander Verdao was more productive than coriander Tabocas. Lower depths of nutrient solution in the hydroponic channels or in the tanks promoted responses in the evaluated variables similar to those obtained under higher solution depths, thus reducing the volume of solution and production cost for growing coriander.