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“Heavenly fair” – this is how a word “orchids” can be translated in Russian. They are standing out even against background of tropical forests bright plants by their original shape, exotic shades and unique aroma. Heavenly fair Starting from a high antiquity orchids have been at- tracting attention of scientists. Even in ancient epoch (370– 300 years B.C.) a Greek botanist Teophrast gave a description of orchids. Confucius mentioned orchids in his works. They were stitched on silk, drawn on paper, imaged on porcelain, described in poems... Ancient Aztecs considered orchids to be divinities and worshipped them, used to decorate temples and ceremonial clothes. Nowadays orchids are decorating coats of arms and flags, being emblems of some countries. Peristeria elata (picture 1) is considered to be a national relic of Panama, its “holy ghost”, it seems like a fragile pigeon with uplifted wings is sitting in the center of this ice-blue flower. Indians of Costa-Riсa from the ancient times has adored an amazingly beautiful orchid – Cattleyaskinneri – and now it is decorating country’s coat of arms. One more species of the genus – Cattleyamossiae – is a national flower of Venezuela. Beautiful Lycaste is a na- Picture 1 tional flower of Guatemala, Epidendrum mutelianum with Peristeria elata bright-yellow flowers in purple lines, having an unusual fra- grance is a symbol of the island Guadeloupe. The Australians were also unable to resist the Orchidaceae. Colorful purple Nowadays about 500 stamps of 88 demonstrating fair Heavenly Dendrobium phalaenopsis was chosen to be an emblem of orchids were issued in the world. Orchids the Australian state Queensland. 1 Lapland state nature biosphere reserve Tropical orchids were brought into Europe only in the XVII variations do exist: it is whole at Limnarchis, Liparis and Pla- century, initially they were delivered in Holland. tanthera, dissected into two blades at twayblade, into three Orchids are represented on stamps. Orchid vanilla blades at Dactylorhiza, all three blades are long and filiform at (picture 2) gives the world the finest and the most expensive lizard orchis, fimbriate – at Pogonia. spice produced from its fruits. In nature vanilla flowers coming The other peculiarity of an orchid’s flower is one stamen. out only in the third year of its life and gladden one’s eyes only This single stamen grows together with a baculum and style. for one day are pollinated by small bees and humming birds. Only Paphiopedilum are an exception – they have two stamens. Vanilla from the island Guadeloupe was the first to be depict- One more systematic attribute of the Orchidaceae is their ed on a stamp in 1905. Nowadays about 500 stamps of 88 pollen. These plants have inferior ovary developing under demonstrating orchids were issued in the world. a flower, fruit-capsule. When ripened, seeds are falling from six The Orchidaceae is the second family in abundance of longitudinal slots. Capsules of tropical species reach large sizes metasperms. There are up to 35 000 wild growing and up (chicken egg-sized), our species are smaller. They are heavier to 150 000 artificially cultivated species and they constitute and smaller in numbers comparing to growing on trees stems. 10 % of all plants in the world. Why do orchids need such abundance of shapes? The answer Among abundance of their species there are no tree or is simple: all manoeuvres are to improve successful cross-fer- shrub forms, all of them are redivives. The majority of orchids tilization. For a long period of evolution these plants has adapt- are epiphytes – they inhabit stems and branches of trees, but ed to pollination by certain types of insects. Result of it was don’t think that are parasitizing on a host plant. Not at all! No- called by a prominent Russian biologist I.I. Mechnikov one of ble orchids use trees only as support growing in cavities and the most surprising and harmonious conformations. fractures of cortex where humus and dust are accumulated. Orchids produce a lot of nectar and pollen and this is a fa- The other group of the Orchidaceae – is ground species. Picture 2 vorite delicacy not only for insects, but also for some species The most wonderful part of the plant is doubtless elegant Orchid vanilla of birds, for example, hummingbirds and sugar birds. Orchids flowers. A broad range of their marking – from sharply white adapted to taste of both. Birds are mainly attracted by red col- and tender pink to bright-green, dark-purple and almost black – ors of corolla, flies – by red-brownish and dirty-purple tones, becomes even broader due to various combinations of shades. butterflies – by ice-white petals shining in twilights of tropical Reticulate, striped and fancy colored flowers are met. Ophrys forests. Orchids grant their floral envelopes to some insects insectífera’s flower (photo of ophrys) resembles a large dark for blowing. Sometimes flowers are alluring insects imitating spider; when waving among branches it can scare even people. their mates. There is one more trick among plenty of the others Ophrys genus orchids are “entertainers”: they learned eas- worth mentioning. It consists in a very long blossom of un- ily to simulate butterflies, bumblebees and even mosquitoes. fertilized flowers. Thus, lady’s slipper waiting for insemination There are species which flowers can be confused with snow- doesn’t droop for more than three weeks, and immediately white pigeons (photo of Habenaria) or sparkling humming- droops after fertilization. Our orchids can blossom up to two birds. Rare flowers called Dracula simian (picture 3) are hiding weeks and tropical orchids can preserve their blossom heads cloud forests in south-east of Ecuador and Peru at the elevation during 2–3 months. about 2 thousand meters. It seems like the nature was in a good Life’ journey from a tiny seed to a gorgeous beauty – or- mood when drawing a monkey’s face on their velvet petals. chid is very complicated and different from the other plants. Orchid flowers amaze us not only by their colors but by Already Charles Darwin paid attention that orchids are trying a shape as well. They consist of six petals organized in two Picture 3 to produce as much seeds as possible. So, one capsule of spot circles. Three petals of the outer circle are almost similar, and Dracula simia leaf orchids can contain more than 6 thousand seeds, capsule the one in the middle significantly differs from the others. For of Gymnadenia conopsea – up to 10 thousand, capsule of but- such irregular shape Goethe called orchids ugly lilies. One can terfly orchid – up to 200 thousand. disagree with an uncomplimentary definition, but there are no But only the smallest part of seeds will survive, at the best doubts that lilies are the first-degree relatives of orchids. Lilies case one per one thousand. Seeds of light-minded beauties are are strict beauties; their hexalobed flower is considered to be almost not supplied with nutritious matters. Strange things an icon of harmony and mathematical accuracy. It has many are not over: their corcule is not divided (as the others are) symmetry axes, whereas flowers of their extravagant relatives – into a radicle, pedicle, bud and seed lobe. In compensation or- orchids have only one. chids’ seeds are very light thanks to a special membrane with The lower petal of the inner circle of a floral envelope air bubbles. doesn’t look like the others, is called labellum and fulfills an Orchids make sure that seeds are leaving their capsules important function during pollination as it serves as a “landing namely in dry “flying” weather. Capsule blades have long hy- field” for insects-pollinators. The main difference of labellum groscopical fuzzes which change their shape in wet weather: is its size – it is larger than the other petals and it has various in dry air they are twisting, mixing seeds and pushing them forms. closer to exit. But during moist weather capsules are swol- Heavenly fair Heavenly The Orchidaceae from Calypso and Paphiopedilum genera len up and safely block this exit. Botanists believe that given have labellum which is overblown and resembles accordingly a good wind and dry weather weightless orchid seeds are able Orchids Picture 4 a fine shoe. Lebellum of the other orchids is flat, but different Habenaria to travel for several tens of kilometers. Somehow or other or- 2 ABCGheritage – Our common arctic heritage variations do exist: it is whole at Limnarchis, Liparis and Pla- chids turned out to be the first plants inhabiting the island tanthera, dissected into two blades at twayblade, into three Krakatoa (Indonesia) where all alive perished in the previous blades at Dactylorhiza, all three blades are long and filiform at century after volcanic explosion. lizard orchis, fimbriate – at Pogonia. Once a seed has landed, it needs adequate moisture and The other peculiarity of an orchid’s flower is one stamen. “patron” – a mushroom. If an environment is favorable, the This single stamen grows together with a baculum and style. embryo begins to develop, forming something strange – col- Only Paphiopedilum are an exception – they have two stamens. orless, spherical, and even covered with unicellular hairs. This One more systematic attribute of the Orchidaceae is their tiny “miracle” (up to 2 mm in diameter) is called protocorm. pollen. These plants have inferior ovary developing under As if realizing that it is not too much attractive, an “ugly duck- a flower, fruit-capsule. When ripened, seeds are falling from six ling” hides underground for a long time: – up to 3 years at but- longitudinal slots. Capsules of tropical species reach large sizes terfly orchids and – up to11 years at orchis. Protocorm grad- (chicken egg-sized), our species are smaller.

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