Oxygen content and its diurnal variation in a new recirculanting water soilless culture for horticultural crops

Based on a new structure for plastic culture channels, a new system for soilless culture called New Growing Systems (NGS) has been developed. It is similar to the nutrient film technique (NFT) but with several potential advantages. Each NGS growing channel has five plastic layers and a large number of holes, there is a dripper every 0.5 m above the first layer of plastic, and each dripper supplies the nutrient solution which flows from the second layer over the others to the end. Three separate greenhouse experiments with tomato, cucumber, and sweet pepper using NGS channels were conducted in Almería (southeastern Spain). The oxygen content in the circulating nutrient solutions was determined at different points and different times along the channels of all crops. Depletion of oxygen content in the nutrient solution was lower than NFT channels. Oxygen content in NGS showed some advantages compared to NFT.