Smallanthus sonchifolius (Poepp. & Endl.) H. Robinson (Asteraceae), known as yacon is a high-altitude tropical herbaceous species. It was introduced into several countries, including Brazil, because of its nutritional potential, high yield but mainly as a source of inulin. Although its agronomy and biochemistry are relatively well established, little is known about the morphology and nature of its underground system, the main inulin source. The underground system is heterogeneous in nature, consisting of rhizophores, and adventitious thin and tuberous roots. The rhizophores and roots present secretory ducts of lipid in the inner cortical layers, which is derived from the meristematic endoderm.
meristematic endoderm; rhizophore; secretory ducts; Smallanthus sonchifolius; tuberous roots