Harnessing Nutrient Uptake Dynamics for Smarter SoillessCultivation of the Apulian Landrace Cucumis melo L. ‘Scopatizzo’

Within the framework of the regional project “BiodiverSO Karpos”, the Apulian landrace Cucumis melo L. ‘Scopatizzo’ was characterized and a valorization pathway was initiatedthrough its cultivation in closed-cycle soilless systems. Building on this eff ort, the presentstudy used ‘Scopatizzo’ as an experimental model to design advanced fertigation strategiesaimed at optimizing water and nutrient use effi ciency (WUE, NUE). The trial assessed theeff ects of diff erent nutrient solution (NS) distribution methods and supplemental LEDlighting (170 μmol m - 2 s - 1 ) on yield, mineral partitioning, and nutrient uptake dynamics in aclosed Nutrient Film Technique (NFT) system. The experiment was conducted in an unheatedgreenhouse (Southern Italy) for 61 days under three treatments: (i) single-point NS supply, (ii)distributed NS through nine drippers, and (iii) single-point NS supply combined with LEDinterlighting. Growth, yield, NS consumption, and macro- and micronutrient partitioning inroots, stems, leaves, and fruits were monitored. Supplemental lighting increased yield by27% and fruit number per plant without increasing NS consumption, improving WUE andNUE by about 30%. Mineral analysis showed distinct patterns of nutrient partitioning:phosphorus and potassium were mainly accumulated in early growth, calcium andmagnesium increased in later stages (particularly in leaves), while iron, zinc, and copperconcentrated in roots and sodium accumulated in roots and stems at the end of the cycle.These results emphasize the importance of dynamically managing the ionic composition ofthe NS in recirculating systems. Establishing daily nutrient uptake curves based oncontinuous monitoring of NS composition could enable real-time adjustment of fertigationto crop demand. The integration of ion-selective sensors for real-time measurement ofnutrient concentrations could make this approach operational, provided their accuracy isvalidated through systematic comparison with laboratory analyses. This study lays thefoundation for nutrient management programs based on daily nutrient uptake in sustainablehydroponic systems.