Environmental and Cultivation Effects on Growth and Phytochemical Profiles of Chicory (Cichorium intybus L.) in Soil, Hydroponics, and Aquaponics

The increasing demand for sustainable food production has intensified interest in controlled-environment agriculture and soilless cultivation systems. This study evaluated the performance of local chicory (<i>Cichorium intybus</i> L., cultivar "Otrantina") grown for 45 days in soil, hydroponics, and decoupled aquaponics under two different environments: a fully controlled growth chamber and a naturally variable greenhouse. Morphological, anatomical, biochemical, and physiological traits were analyzed to assess the combined influence of growth environment and cultivation system on plant development and nutritional quality. Across all parameters, the growth environment emerged as the main driver of plant performance. Greenhouse-grown plants exhibited greater leaf expansion, enhanced mesophyll and vascular development, and higher fresh and dry biomass than those cultivated in the growth chamber. Within each environment, hydroponics consistently supported vigorous growth, whereas aquaponics produced smaller leaves and pronounced root elongation, likely reflecting nutrient and pH instability in the decoupled system. Biochemical analyses revealed system-specific adaptive responses. Soilless cultivation promoted higher lipid accumulation and, under growth chamber conditions, increased protein content. Aquaponically grown plants, particularly in the greenhouse, accumulated elevated levels of soluble sugars and phenolic antioxidants, consistent with stress-related metabolic activation. In contrast, soil-grown plants displayed the highest flavonoid concentrations, suggesting a prominent role of rhizosphere-microbiome interactions in modulating secondary metabolism. Overall, these results indicate that, under the tested conditions, environmental control exerts a stronger influence than cultivation systems on chicory growth and metabolism. Hydroponics proved to be the most efficient system for biomass production, whereas aquaponics requires improved nutrient management to ensure stable growth and quality. The distinct metabolic profiles associated with each cultivation system highlight opportunities to tailor chicory nutraceutical traits within sustainable controlled-environment agriculture.