XVI International Botanical Congess

Dracunculus is a protogynous arum lily with thermogenic inflorescences consisting of male and female florets on a spadix within a floral chamber. Above the chamber, an odor-producing appendix attract flying insects. The appendix produces a large amount of heat and a powerful scent during the first day, but its temperature does not significantly increase, nor does it thermoregulate. Conversely, temperature within the floral chamber is regulated near 18C during the following night. Respiration rate of its florets is inversely related to ambient temperature. Thus temperature regulation is not associated with scent production, but correlates with entrapment of insects inside the floral chamber where they may benefit from the warmth.