مشخصات پژوهش

Selenium (Se) is an essential micronutrient for human health, yet its dietary intake is insufficient in many populations worldwide. Agronomic biofortification represents an effective strategy to enrich crops with Se, and Totally Controlled Environment Agriculture (TCEA) provides a reliable platform to evaluate cultivar-specific responses under standardized conditions. This study evaluated the effects of foliar sodium selenate doses of 0, 5, 10, and 15 µM on two basil (Ocimum basilicum L.) cultivars, ‘Fine Verde’ (FV) and ‘Red Rubin’ (RR), in a micro-TCEA system. The yield was not significantly different at 5–10 µM but declined by 21% at 15 µM, particularly for FV. RR out-yielded FV (+14%), whereas FV produced taller shoots. The 5 µM Se concentration did not affect the total chlorophyll content and quantum yield of photosystem II under control conditions. The highest Se dose (15 µM) decreased the chlorophyll content and electron transport rate by 18% and 12%, respectively, while increasing the stomatal conductance (50%) and transpiration rate (120%). The total phenolics content in RR was double that in FV and increased with Se, whereas the NO3− concentration in RR decreased by 9% at 10 µM. Principal component analysis separated treatments by Se dose (PC1 = 44.5%) and cultivar (PC2 = 42.7%), showing RR’s stronger connection of RR to biomass and antioxidant accumulation under moderate Se. Overall, a single foliar application of 5 µM sodium selenate appears optimal to achieve effective Se enrichment while maintaining productivity and quality. These findings support basil as a promising candidate for Se biofortification in TCEA systems, with potential contributions to dietary Se intake.