Hydroponic production of ‘Biquinho’ pepper with brackish water

In order to generate information about the potential of ‘Biquinho’ pepper as an alternative crop for regions with limited supply of freshwater but with availability of brackish water, such as the semiarid region, a study was carried out with this crop grown in NFT (Nutrient Film Technique) hydroponic system for 120 days after transplanting (DAT). The experiment used nutrient solution prepared in water from the local municipal supply system (electrical conductivity of water –ECw = 0.34 dS m−1) and six other brackish waters prepared artificially by the addition of NaCl, with electrical conductivity of the nutrient solution -ECsol: 2.70 (control), 3.64, 4.58, 5.28, 6.09, 6.90 and 7.77 dS m−1, composing seven treatments repeated six times in randomized blocks. Fruit yield, salt tolerance and yield earliness index were evaluated. The yield of ‘Biquinho’ pepper cultivated in NFT hydroponic system, without restriction of salinity, was 2.87 kg per plant, corresponding to 46.1 Mg ha−1, considering an estimated area of 0.62 m2 per plant. A plateau followed by exponential decay model was fitted to determine the threshold salinity of ‘Biquinho’ pepper, which was 5.22 dS m−1 in the nutrient solution, corresponding to the relative potential yield. Salinity reduced the yield earliness index of ‘Biquinho’ pepper. •Production of ‘Biquinho’ pepper is satisfactory in NFT hydroponic cultivation system.•The threshold salinity of ‘Biquinho’ pepper is 5.22 dS m−1 in the nutrient solution.•The increase in the salinity of the nutrient solution reduces the initial character of 'Biquinho' pepper production.•Nonlinear models better explained the reduction in the relative productivity of ‘Biquinho’ pepper, under NFT hydroponic cultivation.