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WonderParasitic plant fact

Rafflesia arnoldii lives almost entirely inside a tropical vine as a parasite, emerging briefly to produce a vast carrion-scented flower.

Rafflesia arnoldii

NatureBiologyEvolutionScience

The story behind the card

Rafflesia arnoldii grows in the rainforests of Sumatra and Borneo. It is named after Sir Stamford Raffles and the surgeon and naturalist Joseph Arnold, who recorded it in Sumatra in 1818; local people knew it long before. It is a holoparasite: it has no green tissue at all and takes all its water and food from its host, a Tetrastigma vine of the grape family, living as threads of cells inside the vine's stem. A bud swells for many months before opening into a flower up to about a metre across and weighing several kilograms, the largest single flower of any plant. Its smell of rotting meat draws the carrion flies that pollinate it, and the bloom lasts only about a week. Several Rafflesia species are threatened as forests are cleared.

Türkçe oku
Rafflesia arnoldii, tropik bir asmanın içinde asalak olarak yaşar ve neredeyse hiç görünmez. Yalnızca leş kokulu, dev bir çiçek açmak için kısa bir süreliğine dışarı çıkar.

Rafflesia arnoldii, Sumatra ve Borneo'nun yağmur ormanlarında yetişir. Adını, onu 1818'de Sumatra'da kayda geçiren Sir Stamford Raffles ile cerrah ve doğa bilimci Joseph Arnold'dan alır; yöre halkı bitkiyi çok daha önceden tanıyordu. Rafflesia tam asalaktır: hiç yeşil dokusu yoktur ve bütün suyunu, besinini üzüm ailesinden bir Tetrastigma asmasından alır. Asmanın gövdesinin içinde iplik gibi uzanan hücreler hâlinde yaşar. Tomurcuğu aylarca şiştikten sonra açılır. Çiçeğin çapı bir metreye yaklaşabilir, ağırlığı birkaç kiloyu bulabilir; bitkiler âlemindeki en büyük tek çiçek budur. Çürümüş et kokusu, onu tozlaştıran leş sineklerini çeker. Çiçek yalnızca bir hafta kadar açık kalır. Ormanlar kesildikçe Rafflesia türlerinin birçoğu tehlikeye giriyor.

Sources and further reading

Background reading: Rafflesia arnoldii
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