Sepal Identity of the Pappus and Floral Organ Development in the Common Dandelion (Taraxacum officinale; Asteraceae).

ABSTRACT: The dry one-seeded fruits (cypselae) of the Asteraceae are often crowned with a pappus, an appendage of hairs or scales that assists in dispersal. It is generally assumed, but little investigated, that the pappus represents the outer floral whorl where the sepals are usually located. We analysed pappus-sepal homology in dandelions using micromorphological and floral gene expression analyses. We show that the pappus initiates from a ring primordium at the base of the corolla, heterochronic to the petals. Pappus parts form from this ring, with those in the alternipetalaous position usually being ahead in growth, referring to sepal identity. Tof-APETALLA1 expression increased during floret development and was highest in mature pappus. Tof-PISTILLATA expression was high and confined to the flo

SUBMITTER: Vijverberg K 

PROVIDER: S-EPMC8398263 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature