ABSTRACT
Sustainable hydroponic lettuce production with artificial lighting and different nutritional irrigation parameters

Glauco V. Miranda1*, Oneir S. Molina1, Dayane Carvalho2, Jakeline da S. Andrade3, and Pedro L. de Paula Filho3
 
The hydroponic indoor production of lettuce (Lactuca sativa L.) represents a technological advancement in cultivation methods, emphasizing sustainability. This study aimed to identify the optimal management strategy for indoor hydroponic crisp lettuce (L. sativa L. var. crispa L.) production under artificial lighting and varied nutritional and irrigation parameters. Experiments were conducted in a refrigerated container using hydroponic benches with six hydroponic profiles with nutrient film techniques, each with an independent management system. The crisp lettuce ‘BS AC0055’ was harvested 21 d post-transplantation. The optimal management for combinations of irrigation interval (IR), electrical conductivity (EC), and pH was found to be 16 min, 1.6 dS m-1, and 6.10, respectively, resulting in productivity of 138 g plant-1. It is concluded that optimal pH plays a crucial role in determining the significant impact of IR and EC on plant productivity. Once the ideal EC 1.9 dS m-1 is achieved, the irrigation interval becomes secondary in the range of 22 to 42 min, given that the pH is also maintained within the appropriate range of 6.0 to 6.2. The study also demonstrated the attainment of highest productivity through various combinations of irrigation interval, EC, and pH.
Keywords: Controlled environment agriculture, protected environment, urban agriculture, vertical farm.
1Universidade Tecnol?gica Federal do Paran?, Santa Helena, Paran?, Brasil.
2Faculdade Unigua?u, São Miguel do Igua?u, Paran?, Brasil. 3Universidade Tecnol?gica Federal do Paran?, Medianeira, Paran?, Brasil.
*Corresponding author (glaucovmiranda@utfpr.edu.br).