Leaf anatomy of the genus Smallanthus (Asteraceae, Millerieae).

Abstract

Leaf anatomy of the genus Smallanthus (Asteraceae, Millerieae). Given the great medicinal and nutritional importance of the leaf in Smallanthus species, such as the world famous “yacón” (Smallanthus sonchifolius), and that so far only have been studied four of the 23 species that constitute the genus, the leaf anatomy of all species of Smallanthus is analyzed here. A table of uses and vernacular names of the species of Smallanthus and a general description of leaf anatomy, including the petiole is presented. Three types of trichomes were identified: an eglandular simple conical hair, a glandular biseriate vesicular hair, and a glandular biseriate capitate subtype beta hair. Smallanthus species show almost no differences in the anatomy of the blade and petiole. The schizogenous secretory channels show a tendency to increase in number in the southernmost species.