After Rafflesia arnoldii, Amorphophallus titanum (also named as Titan arum) is considered to be the plant with second largest flower in the world and the two are most often dealt with together. This is, however, a general misconception as the giant structure is not the flower but a collection of flowers i.e. inflorescence which is unbranched and biggest of all plants. It is also named Titan arum and classified as vulnerable in 1997 by International Union for Conservation of Nature (IUCN). Just like the largest, the second largest flower in the world, although beautiful to look at, smells deceptively bad.
The first encounter to this plant happened in 1889 when Italian Botanist Odoardo Beccari travelled to tropical Southeast Asia. He sent back seeds to his patron in Italy and one of the young plants that germinated from them was subsequently dispatched to Kew, where it flowered in 1889, exciting great public interest. In 1926, when it flowered again, the crowds attracted by the phenomenon were so large that the police were called to control them.
The plant belonging to family Araceae (Order Alismatales, class Equisetopsida) is native to rainforests of Sumatra, Indonesia. The inflorescence can reach over 3 metres (10 ft) in height. Both male and female flowers grow in the same inflorescence. The female flowers open first, then a day or two following, the male flowers open. This usually prevents the flower from self-pollinating. The flower remains open for 48 hours. Corm is the largest known, typically weighing around 50 kilograms (110 lb) but may reach 91 kilograms (201 lb). In 2006, a corm in the Botanical Garden of Bonn, Germany was recorded at 117 kilograms (258 lb). The titan arum generally requires 7–10 years to bloom. However, considerable variation in blooming frequency is reported with occasional back-to-back blooms occurring within a year and corms simultaneously sending up both, a leaf (or two) and an inflorescence. Corms producing multiple simultaneous blooms are also on the record. At Kew gardens, several specimens are always there making it possible to always see a plant in leaf and flower. Interestingly, however, the flowering being rare and unpredictable, it always grabs the news headlines.
Due to its odour like that from a rotting animal, the titan arum is characterized as a carrion or corpse flower (bunga bangkai in Indonesian). The deep red color and texture of inflorescence (Spadix) gives the illusion of a piece of meat. The “fragrance” attracts carrion-eating beetles and flesh flies that serve as pollination agents. The odour gradually increases from late evening until the middle of the night, when carrion beetles and flesh flies are active as pollinators. In fact, most of the 170 or so species of Amorphophallus produce a variety of obnoxious odours ranging from rotting meat, dung and rancid cheese to a nauseating gaseous stench. However, few species like A. haematospadix and A. dunnii produce pleasant odours like that from bananas (due to Isoamyl acetate) and freshly chopped carrots (due entirely to 1-phenylethylacetate), respectively.
Analyses of stinky chemicals released by the spadix show the presence mostly of sulfur containing compounds. Some of these chemicals are i) dimethyl trisulfide (like limburger cheese), ii) dimethyl disulfide, iii) trimethylamine (rotting fish), iv) isovaleric acid (sweaty socks), v) benzyl alcohol (sweet floral scent), vi) phenol (like chloraseptic), and vii) indole (like human feces).
Viewing the above, it would appear that this plant provides an alternate food for the life forms that feed on rotting matter of animal origin. Thus nature provides livelihood for all types of life in all kinds of habitats. However, the plant being not so common in distribution, its utility as feed for carrions is difficult to understand; means to attract them for purpose of pollination notwithstanding. Amazingly, however, this plant, carrying the second largest flower in the world, is an immense human attraction when it blossoms, mainly for the unusual size of its inflorescence; stink not being a hindrance to the view that is fairly rare.