Jumat, 29 Januari 2010

Anggrek Thailand

Seperti halnya di Indonesia, hutan Thailand juga menyimpan kekayaan anggrek Hutan yang beraneka ragam. Permasalahan yang sama yang di hadapi bangsa Indonesia yaitu ancaman hilangnya spesies-spesies anggrek hutan karena faktor alami maupun kelalaian manusia. Sudah sepatutnya masyarakat untuk lebih peduli dan lebih reaktif terhadap keadaan ini terutama kita pecinta dan penikmat anggrek khususnya anggrek alam.

Anggrek Simpodial dan Anggrek Monopodial


All Orchids have their own unique characteristics and charms. The mere fact that their roots live on air is enough to make us wonder how they can sustain themselves. The roots of the orchid are different from those of other plants, consisting of a special sponge-like layer of tissues called velamen that covers up the true roots inside. This special sheathing acts as a moisture collecting device while protecting the roots underneath from direct sunlight. The orchid's green leaves play the actual role of food manufacturing. Orchids are epiphytes, that is the roots' main duty is to grasp and cling to other larger structures such as trees, without in any way harming or taking away food from the host, unlike a parasitic plant. Some orchids have roots that go into the ground like most other plants, while others even find unusual places to grow such as in the crevices of rocks on the side of a cliff. Orchids are monocotyledonous plants and have two different types of growth structures. One is to grow from the vegetative apex (monopodial), an example being the Vanda Coerulea. The other is to grow out horizontally (sympodial), sending pseudobulbs up from the rhizome. The new shoots will collect and replenish the old ones with food, Orchids that grow in this fashion are, for instance, Dendrobiurn chrysotoxum, and so on. The flowers are what clearly distinguish one orchid from another. Some bear large flowers of bright hues, and some have smaller or even tiny little flowers of softer tones. They may flower singly or in small groups of two or three per stem. Others will bloom in a big cluster or a bunch with some standing up on an erect stem and yet others bending down in a flowing cluster. Some have flowers that bloom in alternating sequences and take quite a few days to wither while some bloom and wither together and do not last as long. The scent of orchids also differs, ranging from those without any smell to a soft and subtle scent through to a more full-bodied and pungent fragrance. Each orchid flower has two sets of petals consisting of three outer and three inner ones. The three inner petals will usually consist of an identical pair and a singular one with distinctive features both in shape and colour. This single petal, which most often will be brighter in colour, is called the "lip" or "labellum". The pouch-shaped lip of the Lady Slipper orchid usually looks like the toe of a shoe. The outer petals are generally smaller and do not have as vivid a colour as the inner petals. They may also have a pair with an identical look and a singular one like the inner petals, or all three of them may look the same. Inside the blooms are the stylis with the stigma, fused with the filament and anther. The poilinia--the mass of pollen--has the appearance of a tightly squeezed clump of wax. When the pollen comes in contact with the stigma, the bloom will rapidly wither and the ovary located at the base will expand into a pod, which will take from six months to one year to ripen. As maturity peaks, the full grown pod will burst open longitudinally and the mass of minuscule seeds inside will be distributed into the air. Some of these pods can contain millions of seeds. The seeds will be, air-borne until, with great luck, some land on a spot of a host tree which happens to be covered with a kind of fungi called mycorrhiza which is essential to help in finding food during the first part of the seedling's growth, until it can mature into another orchid plant. Most wild orchids bloom only once a year. Those that do so more than once are rare. The times of year that certain orchids bloom are as follows: December through January starting with the flowering of Rhyncostylis Gigantea; while Dendrobium Aggregatum, Dendrobium Chrysotoxum and Dendrobium Thyrsiflorum, the clustered orchids usually bloom in February and March. Whereas the Rhyncostylis Retusa follows in April and May right along with Aerides Odorata, Aerides Falcata and Aerides Multiflora. July and August is the time for Vanda Coerulea. Those mentioned are only some of the more prominent and better known ones. There are quite a lot more orchids which bloom at different periods of the year. Aerides Crassifolia, Ascocentrum Curvifolium, Bulbophyllum, Bulbophyllum-Dearei, Bulbophyllum-Obii, Bulbophyllum-Picturatum, Cirrhopetalum, Cirrhopetalum-Louis-Sander, Cirrhopetalum-Umbelatum, Dendrobium Cariniferum, Dendrobium Draconis, Demdrobium Harveyanumto name a few. There are quite distinct differences between wild orchids and cultivated orchids nowadays, particularly in the sizes, shapes and colours. For example, the Wild Vanda Coerulea has a paler shade, the tesselation is not as clear and as vivid, and the petals are significantly more twisted (although retaining their natural beauty) than the Vanda Coerulea sold in the market. Breeders have improved and altered those features by bringing some specimens from the wild to cultivate, then using the process of either self-pollination or cross-pollination to develop hybrids. The seeds from the pods of these new "breeds" are then brought to the laboratory for further embryo culture, cultivation and selection to obtain the features desired. Generally the features sought by these processes are brighter colours, more obvious tesselation, and less twisted petals so that a circular form is achieved. Other than self-pollinating and cross-pollinating, the orchids are sometimes pollinated from orchids of different species and families in order to obtain other special features such as, in the case of Vanda SP. for example, being able to produce flowers more than once a year. Another distinct quality of the wild orchid is its vigour and resistance to diseases and insects, plus its ability to withstand adverse environmental factors, and the fact that it can produce a great quantity of seeds at one time. In some cases, there is still a need to re-pollinate the already cultivated and hybridised orchids from wild orchids once more in order to regain some of the missing features in response to the market trends of the moment. So, it can be clearly seen that wild orchids are the source of essential factors and play an important role in the continuing development and maintenance of healthy hybrids. Thus they should always be highly regarded and preserved with utmost care. As mentioned earlier, most wild orchids flower only once a year and the form of their blooms are not those most popular on the market, so not too many people raise them except the enthusiasts of wild orchids who truly love their natural looks, who may also raise them for experimental and hybridization purposes. We don't know how many of our Thai orchids have already become extinct, both from natural causes such as many fungal diseases, insects or forest fires, and from human negligence. Not realising the dangers of extinction, villagers and dealers are cooperating in collecting wild orchids from the forests in increasing number in order to supply the annually rising international demand for Thai wild orchids. It is to be hoped that the problem of wild orchid conservation, along with the conditions and problems faced by the existing forests, will be looked into and dealt with soon, before it becomes too late. Although leaving the orchids in their own natural environment could be the best way to preserve them, a small number of orchids should perhaps be brought out from the forest for research or for conservation purposes. Our hope is that some of the charms of these Thai wild orchids may have already touched your heart and fascinated you with their forms and colours.
Nature has given us these splendid plants and hopefully their beauty will create in all of us a consciousness of and a love for nature, along with the Thai forests where they come from.

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