Molecular analysis of orchid pollinaria and pollinaria-remains found on insects

Authors


Alex Widmer. Fax:. + 41 (0)1 632 14 63; E-mail:alex.widmer@geobot.umnw.ethz.ch

Abstract

Direct observations of pollinator visits to orchids are often difficult and time consuming, especially in orchids with a deceptive pollination system where seed set is typically pollinator-limited. This lack of direct observations greatly inhibits our understanding of orchid–pollinator relationships and especially the degree of pollinator-specificity. Here we describe a molecular approach to the study of orchid–pollinator relationships based on the analysis of DNA recovered from pollinaria found on insects. The insects were collected from nectar-rich plants flowering near natural orchid populations, or taken from museum collections. Sequence analysis of the nuclear ribosomal ITS region allowed the identification of the orchid species or species-group from which the pollinaria originated. Four out of eight orchid–pollinator relationships established with this approach have not been reported previously, which highlights the value of molecular tools for the study of orchid pollination biology.

Ancillary