Reusing Coir-Based Substrates for Lettuce Growth: Nutrient Content and Phytonutrients Accumulation

• Autor(a) principal: Machado, Rui M.A.
• Data de Publicação: 2023
• Outros Autores: Alves-Pereira, Isabel, Alves, Inês, Ferreira, Rui M. A., Gruda, Nazim S.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Texto Completo: http://hdl.handle.net/10174/37572; https://doi.org/Machado, R.M.A.; Alves-Pereira, I.; Alves, I.; Ferreira, R.M.A.; Gruda, N.S. (2023) Reusing Coir-Based Substrates for Lettuce Growth: Nutrient Content and Phytonutrients Accumulation. Horticulturae, 9, art. no. 1080. https://doi.org/10.3390/ horticulturae9101080; https://doi.org/10.3390/ horticulturae9101080
• topic: Lactuca sativa; soilless system; short-cycle crops; municipal compost; biochar; total phenols; flavonoids; ascorbic acid; circular economy

This research aimed to assess the influence of reusing coir-based substrates on growth, nutrient content, and phytonutrients accumulation in lettuce. The experiment included a new coir pith and four coir-based mixes (1) coir, biochar, and perlite; (2) coir, compost, and perlite; (3) coir, biochar, and pine bark; and (4) coir, compost, and pine bark. All mixes had been previously utilized to grow transplanted spinach and possessed identical ratios of 78:12:10% (v/v) among their components. Lettuce (Lactuca sativa L. cv. ‘Godzilla’) seedlings were transplanted into Styrofoam plant boxes. Each day, the planting boxes received a nutrient solution via drip irrigation. Plants grown in reused mixes had similar macronutrient concentrations as those grown in coir for the first time, except for N and K in the third mix. Plants grown in reused mixtures had similar yields as those in new coir. Lettuce heads yielded 4.6–4.9 kg/m2, while plants grown in reused mixtures had equal or higher total phenols than those in new coir. Ascorbic acid content was higher in plants cultivated in reused mixes. Coir-based growing media can be reused for another short-cycle crop, like lettuce, without yield loss or phytonutrients decrease.