Smooth golden fleece and prickly golden fleece as potential new vegetables for the ready-to-eat production chain

Smooth golden fleece (Urospermum dalechampii (L.) F.W. Schmidt) and prickly golden fleece (Urospermum picroides (L.) Scop. ex F.W. Schmid) are two wild edible plants used in traditional cuisine and folk medicine. In this research, the domestication of both species was tested for the first time using a floating system and two plant densities (412 and 824 plants m−2) to evaluate yield and quality. Some quality traits were also compared in cultivated plants and wild ones gathered in grasslands. The results show that both species are suitable for cultivation, although prickly golden fleece showed highest total phenols (132 mg 100 g−1 fresh weight—f.w.) and total antioxidant activity (0.19 mg 100 g−1 f.w.). At low sowing density, smooth golden fleece showed a nitrate content of about 7200 mg kg−1 f.w., 38% higher than plants of the same species grown at high density and plants of prickly golden fleece. These results suggest that high density can be used to optimize yield in two harvests. By permitting modulation of nutrients and a product without soil residues, the floating system used in this study proved suitable for growing U. dalechhampii and U. picroides as new vegetables for the ready-to-eat production chain.