Titan Arum: Amorphophallus titanum

The largest (unbranched) flower inflorescence in the world

The stake to the world's largest flower can be given to one of many different plants, depending on how you classify flower.  Technically the plant with the largest flower is the parasitic Rafflesia arnoldi from the indonesian islands.  The absolute largest flowering inflorescence, is the massive terminal stalk that shoots out of the amazonian Talipot palm (Corypha umbraculifera).  But, the largest single, unbranched inflorescence goes to the titan arum (Amorphophallus titanum), it is truly an amazing sight to be seen.

Whats in a name: Amorphophallus titanum

The scientific name for the titan arum is Amorphophallus titanum.  Its roots are Greek.  Amorphos means "without form" or "misshapen".  Phallos peans "penis" and titan means "giant".  I'm sure the phallic figure of a blooming titan arum does look a bit like a misshapen giant penis, especially to explorers that were trecking through the hot Bornean jungles.  The common name titan arum, refers the fact that it is an giant arum, the name given to members of the family Araceae.

How does the titan arum attract pollinators

Like the largest single flower, the Rafflesia, the Titan Arum emits an unmistakable corpse-like smell.  It attracts putative pollinators such as carrion beetles and blow flies that might otherwise be looking for a piece of a carrion. A combination of the smell and the heat released by the arum creates a much stronger attraction for these insects. 

Background on the Plant

The titan arum was discovered by Odoardo Beccari in Sumatra in 1878. Corms, which may weigh as much of 100 pounds and have a diameter of half a meter were brought back to botanical gardens. Yet, the plant has bloomed very few times in the gardens and when it does flower the nearly six foot yellow-red stalk lasts for only about 3-4 days.

In 2006 a rare botanical flowering event occurred where three titan arums flowered at the same time.  A study by Barthlott studied the heating of the central column.  He showed that the central column would heat up in pulses originating from the base.  It would reach a temperature of 36 degrees.  The following is a picture from that study.

References and Links

• Gandawijaja, D. Idris, S., Nasution, R., Nyman, L.P. and J. Arditti. Amorphophallus titanum Annals of Botany 51: 269-278, 1983 © 1983 Annals of Botany Company Becc.: a Historical Review and Some Recent Observations.
• A torch in the rain forest: thermogenesis of the Titan arum (Amorphophallus titanum) titanum Plant Biology, 2008