Thursday, February 10, 2011

Top 5 parasitic plants

Our top 5 parasitic plants - these freeloaders have ways of getting what they need from hosts that are clever or downright bizarre.



Top 5 parasitic plants

Researchers have discovered that a parasitic plant emits a plastic-like 'perfume' smell to attract small mammals that it uses to pollinate its flowers.

The South-African plant, Cytinus visseri, buries itself into the host scrub in order to obtain its supply of chlorophyll.

There are over 4,000 species of parasitic plants. They all have a special root, called a haustorium, which is used to pierce the host and reach its xylem or phloem. Here are our top five:
1) The Corpse Flower (Rafflesia arnoldii)

Not only does this plant boast the world’s largest flower - at over 1m in diameter - it also smells strongly of rotting meat.




2) Mistletoe (e.g. Viscum album)

Much-sought around Christmas time, these familiar white-berried plants live on the branches of trees and shrubs. They are known as ‘hemi-parasites’ because, though they do feed off their hosts, they can also sustain themselves through photosynthesis.
3) Western Australian Christmas Tree (Nuytsia floribunda)

This is another hemi-parasite and has been known to damage underground cables by attaching its haustoria (root) to them. It gets its name from the bright orange flowers that appear on the plant around the Christmas season. For more information see the Australian Native Plants Society.
Cacti4) Cactus Mistletoe (Tristerix aphylla)

Found in Chile, this bright red parasite thrives on cacti, making a pretty dramatic combination.
5) Bird’s-nest Orchid (Neottia nidus-avis)

These plants are unusual because they feed off a fungi that is itself feeding off a photosynthetic host, a technique which classes them as ‘myco-heterotrophs’. They live entirely underground beneath Beech trees. The only time you might catch a glimpse of a Bird's-nest Orchid is in summer when it pokes up a yellow flowering stem.

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