Effect of microalgae biomass concentrations and electrical conductivity of the nutrient solution on the production and quality of lettuce seedlings in indoor vertical cultivation

• Grant number: 25/17208-0
• Support Opportunities: Scholarships in Brazil - Master
• Start date: January 01, 2026
• End date: February 28, 2027
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Luis Felipe Villani Purquerio
• Grantee: Amanda Cavallari Augusto
• Host Institution: Instituto Agronômico (IAC). Agência Paulista de Tecnologia dos Agronegócios (APTA). Secretaria de Agricultura e Abastecimento (São Paulo - Estado). Campinas , SP, Brazil

Abstract

The production of robust seedlings is fundamental to the success of lettuce cultivation, especially on a large scale, where specialized nurseries are commonly used. Currently, seedling cultivation in agricultural greenhouses is predominant, but the indoor vertical system with artificial lighting emerges as an innovative alternative, offering greater environmental control and potential for quality and acceleration of the cultivation cycle. Among the innovations incorporated by agriculture to increase efficiency, sustainability, and production quality, the use of bioinputs, such as beneficial microorganisms and plant extracts, stands out, improving nutrient absorption and reducing the need for chemical inputs. Among the bioinputs, the green microalgae of the genus Chorella sp. stands out, rich in bioactive compounds such as amino acids, vitamins, and phytohormones, which promote plant growth and increase tolerance to abiotic stresses. The combination of indoor vertical farming with the use of Chlorella sp. can improve lettuce seedling production. The objective of this research is to verify whether the productivity and quality of tropicalized lettuce seedlings produced in indoor vertical farming is enhanced by different concentrations of Chlorella sp. microalgae biomass (0.0, 0.5, 1.0, 1.5, 2.0 g L-1) and electrical conductivity of the nutrient solution (1.1 and 1.8 mS cm-1) and whether the effect observed is maintained after cultivation in a nutrient film technique (NFT) hydroponic system. Evaluations will be carried out on seedlings and plants at the horticultural harvest point for biometrics, macro and micronutrient contents in the aerial part, and root development, with the aid of WinRHIZO software. (AU)