Roses exhibited higher production and postharvest longevity in response to nano-nutrients of Fe, Ca and Zn under LED supplemental lighting

In greenhouse production systems, enhancing photosynthesis, a biophysical-chemical process that converts carbon dioxide into organic compounds using light as an energy source, is of vital importance. This study was conducted to evaluate the effects of two types of supplemental lighting including high-pressure sodium (HPS) and light-emitting diode (LED) vs. control (CL) and three concentrations (0, 1, and 3 mg L−1) of nano-nutrients (Fe, Ca, Zn) on ‘Jumilia’ and ‘Samurai’ rose cultivars’ growth performance, photosynthesis functionality, nutrient content, production, and vase life using an L9 (27) orthogonal array layout by Taguchi statistical methodology. Results demonstrated that higher mean leaf nutrients and photosynthetic parameters led to increased production performance and postharvest longevity. Production and postharvest longevity of LED-exposed roses increased by 33.3% and 34.7% in ‘Jumilia’ and 34.0% and 44.4% in ‘Samurai’, respectively, in comparison to CL. Moreover, by increasing the concentration of nano-Fe to the level of 1 or 3 mg L−1 and adding nano-Zn in 1 mg L−1 and nano-Ca in 3 mg L−1, the rose production and postharvest longevity of both cultivars significantly increased. Taguchi statistical methodology suggested that supplemental lighting made a higher-ranking response compared to nano-nutrient application and Fe nano-chelate had a higher rank of response compared to Ca and Zn nano-nutrients for rose photosynthesis and production. Our analysis indicates that enhancing nutrient absorption efficiency by manipulating light quality and application of nano-elements may be a promising strategy for rose qualitative production management.