Tuesday, August 9, 2011

Underground Orchid ???

        Selalunya kita lihat pokok orkid yang tumbuh di atas pokok atau di atas tanah..tapi Kali ni kita tengok pula sejenis orkid yang tumbuh di dalam tanah..Namanya ialah Rhizanthella gardneri, spesis yang sangat jarang dijumpai ini hanya terdapat di negara Australia. Kalau siapa yang tidak pernah tengok saya tunjukkkannya di sini..Sungguh unik dan membuktikan kepelbagaian genus orchidacea yang tidak ada pada tumbuhan lain..


         Rhizanthella gardneri
is a cool growing terrestrial orchid from the genus Rhizanthella.
The plant blooms in May and June and measures 2.5–3 cm. The flower head contains 8 to 90 small dark maroon flowers.The white leafless plant is made up of a tube which produces a flowerhead. Unlike any other orchid in Australia, the Western Australian underground orchid remains completely underground for its whole life. Not being able to obtain the sun's energy, it instead feeds on the broom honey myrtle, a shrub. It is linked to it by a fungus named Thanatephorus gardneri.
         The plant was discovered in the spring of 1928 when Jack Trott had bent to investigate an odd crack that had appeared in his garden's soil, and had noticed a sweet smell that arose from the ground. Scraping away the soil, he soon uncovered a tiny white flower, about half an inch across, growing underground. What he had found was an entirely new type of orchid.
This particular orchid is a myco-heterotroph as it relies completely on the Melaleuca uncinata and a mycorrhiza fungus for its nutrients and carbon dioxide. Having received this from the fungus the plant is then able to convert the water, nutrients and carbon dioxide into the energy needed for growth and maintenance.
         Rhizanthella gardneri reproduces vegetatively by which it can produce three daughter plants, as well as sexually. In the latter case the pollinated flower will then take six months to mature - pollination is thought to be effected by some animal species attracted by the fragrance. The seed is thought to be dispersed by Marsupialia, who eat the fruit, but substantial findings are hard to come by as only 19 mature specimens of the orchid are known to currently exist in the wild and only 300 specimens have been collected to date. Plant is found in the sandy dry soil of Western Australia at elevations of 300 to 400 meter





Spesis orkid yang unik ini adalah bersifat parasit, iaitu bergantung kepada tumbuhan lain untuk hidup..Tumbuh dan berbunga sepenuhnya di dalam tanah. Hanya terdapat di kawasan yang sangat terhad di bahagian barat Australia.

A very bizarre species, an endemic parasite, can be added to the long list of known orchids. This species grows and blooms totally underground while attached to the roots of shrubs in a highly restricted zone of Western Australia.


Discovered in 1928 but not thoroughly investigated until recently. This may be due to the fact that it is extremely rare, with only 50 known individuals


 Keseluruhan pokok orkid ini tumbuh dan berbunga di dalam tanah berpasir.


  Sekeliling bunganya dikelilingi 'tampuk' yang menyebabkannya kelihatan seperti bunga tulip. Bunganya yang sebenar ialah yang berwarna merah hati di tengah-tengah tu..

The tulip-like inflorescense of the Western Underground Orchid



Dengan hidup di bawah tanah orkid ini terlindung dari kekeringan dan kemarau. 

The orchid had to make a Faustian deal to receive this protection: without the light of the sun to nourish it, the orchid became a parasite.

 
 The white leafless plant is made up of a fleshy underground storage stem (or tuber), which produces flower head consisting of around 150 tightly packed, tiny flowers.


  This subterranean and parasitic lifestyle is a big change from normal plant life. Other plants use their green chloroplasts to obtain energy from the sun via photosynthesis. But underground, Rhizanthella no longer needed its chloroplasts. Its flower bract turned purple instead of green.


Rhizanthella gardneri is a cute, quirky and critically endangered orchid that lives all its life underground, making it virtually unique amongst plants.


 
 Gambar jarak dekat yang menunjukkan kluster bunganya yang berwarna merah hati.

The plant blooms in May and June and measures 2.5–3 cm. The flower head contains 8 to 90 small dark maroon flowers.The plant blooms in May and June and measures 2.5–3 cm. The flower head contains 8 to 90 small dark maroon flowers.


 Close up of the flowers clustered in the centre



 Unlike any other orchid in Australia, the Western Australian underground orchid remains completely underground for its whole life. 
 


For Rhizantella the dependency on the fungus and broom bush comes on top of its dependence on termites for pollination of its flowers and mammals for the dispersal of its seeds. With so many delicate interactions with other species, no wonder it’s so rare. 


 Rhizanthella gardneri reproduces vegetatively by which it can produce three daughter plants. They also undergoes sexual reproduction, and underground insects such as termites and gnats attracted by the fragrance. The pollinated flower will then take six months to mature.


  Even if you had the luck to wander near this beautiful orchid, you still wouldn’t notice it, because it lives several centimetres below the ground. Its maroon flowers never see the light of day.


 Rhizanthella gardneri Underground Orchid View with only leaf litter removed.



.
Rhizantella Gardneri close-up



 Habitat - Melaleuca uncinata (Broom Bush) thickets



"Full many a flower is born to blush unseen,
And waste its sweetness on the desert air."
-  Thomas Gray 


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