Light spectrum differentially modulates physiology and secondary metabolism in underutilized leafy greens grown in aeroponics

Conventional agriculture faces growing concerns regarding sustainability, biodiversity, and nutritional quality. Aeroponic systems, coupled with optimized light spectra, present a potential solution for enhancing crop performance and minimizing environmental impact. This study examines the morphophysiological and antioxidant responses of four neglected and underutilized plant genetic resources leafy landraces (Cichorium intybus 'Cicoria del Marzocco', Cichorium endivia 'Radicchia di Lucca', and Lactuca sativa 'Foglia di Cerro' and 'Rossina di Pescia') grown aeroponically under different red:blue light ratios, with and without far-red light supplementation. Plants were grown under seven LED light treatments, and growth parameters, gas exchange, photosynthetic efficiency, and antioxidant profiles were assessed. The results showed genotype-specific responses to light quality. Far red light significantly increased biomass accumulation and leaf expansion in L. sativa but had little effect on Cichorium species. Blue light reduced growth but increased polyphenol and flavonoid content across all genotypes. Principal component analysis indicated that genotype had a greater effect on overall physiological variation than light treatment. These results suggest that manipulating the light spectrum can differentially affect growth and secondary metabolism in traditional leafy crops. Genotype-specific light strategies may promote the use of neglected germplasm and the development of sustainable, high-efficiency cultivation systems.