Каминяр Дмитрий Генаддьевич : другие произведения.

N. Verzilin. A plant of the tropical swamps

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A PLANT OF THE TROPICAL SWAMPS

   Plants can have strange names. For example, one of the widespread domestic plants earlier was called "tattle tales". The scientific name of this plant is better sounding - tradescantia, given in honor of the XVII century botanic, John Tradescant, who had visited Moscovia in 1618 with the goal to study the flora of our north.
   The tradescantia belongs to the dayflower family of the monocots.
   This family is named after the dayflower (Commelina).
   So why the nonprofessional name of the tradescantia is "tattle tales"?
   If one looks at this plant with its long drooping stems that is usually suspended in a pot on a window, then one can find similarity with tattle-tales. The stems, drooping from the pot are densely covered with lancet-like leaves that jut everywhere, and are intertwined all over, so it is hard to separate them from each other, to find the beginning or the end of a branch.
   "Tattle tales" live on the swamps of America's tropical forests.
   This plant is used to moist soil, to receiving little light; its stems are located on the surface of soil and fasten to it with rootlets that grown on branches, reproducing in a vegetative style.
   The stems are very fragile and easily break off, but bits of them grow roots.
   The stems of tradescantia often wither, starting at the roots, but at the end of a dry stem, a juicy twig with green leaves continues to live for a long time. This is the adaptation of the plant for the vegetative reproduction.
   Under the leaves, which grab the stem with their lower parts, there is an inflammation or a knot that contains small buds of roots. Nearby around it one can see transparent hairs, which apparently, catch water droplets thus allowing the formation of roots.
   During rains, water overwhelms these plants, but they do not live but live underwater.
   Despite the life of tradescantia in moist conditions of swampy and humid air, its' leaves in bright light form a line of watery cellular tissue, sometimes several.
   Cacti, aloe and agaves have previously shown water-holding tissues on the inside - this plant has it on the outside, above the chlorophyll-holding cells.
   Why the tradescantias, if put onto bright sunlight, suddenly grow pale, become greyish, pale green?
   It is because they form the water-bearing tissue that protects them from sunlight.
   Tradescantias exist not just in the green variety (viridis), but also with white stripes (zebrine - zebra-like), with brown, pinkish-violet, silver stripes (multicolor), and with furry, hairy stems and leaves (T. pilosa).
   The tradescantias with striped leaves feature this adaptation: they become greener in shade, and in sunlight, their coloration becomes brighter.
   Back in its' homeland, the tradescantia blooms during the dry season.
   This plant sometimes blooms indoors too (especially T. pilosa). The flower is a bloom with small petals. All parts of the flower, like in case of the other monocots, divide into three.
   The flower has three green petals forming a cup and three pink or blue-violet petals, three big and three small stamens that do not always develop. A fertilized flower forms a box-like fruit.
   The stamens have noticeable hairs that are very valued by scientists: under the microscope, their cells are very noticeable as is the movement of protoplasm.
   This domestic plant was the subject of the first scientific experiment by the Russian scientists N.I. Zheleznov, the first director of the Petrovskaya, now Timiryazevskaya agricultural academy.
   In 1840 the 24-year-young scientist, working with a magnifying glass and a microscope, had studied the development of the flower, petals, stamens, their hairs, pollen, fertilization and seeds of the plant called "tattle tales" and disproved the incorrect statements of the German scientists.
   For this work--"On the development of flower and fruit in a plan"--N.I. Zheleznov received the master's degree. He wrote the first Russian work on the plant physiology.
   If a tradescantia lacks flowers, one can look at the cells and the protoplasm of the thin hairs that cover the leaf bases.
   If a tradescantia twig is put into moist ground that is in a wide-mouthed bottle, then the knots under each leaf will sprout thin air roots that are covered in hairs.
   It is interesting to look through the glass at the dense stems of tradescantia with the downwards-dropping long `air' roots. It is quite a `landscape' of a tropical forest.
   When growing a tradescantia in a bottle one should compare the roots that have grown inside and outside.
   The twigs of the tradescantia will quickly crawl out of the thin mouth of the bottle.
   Scientists highly value the leaves of the tradescantia. The lower sides of leaves have visible `openings', that is - closing and opening holes that pull the oxygen and water vapour in, visible through the microscope and even through a strong magnifying glass. When it is hot, they are open, and evaporating water cools down the tender leaflets.
   The chlorophyll cells undertake a lot of work in sunlight: the carbon dioxide, once inside and in contact with water, forms sugar and starch. The openings are open all day long and close at night. Still, if there is not enough water in the soil and the weather is very hot, then the openings also close if there's too much moisture lost.
   Thus, the tradescantia is not just an interesting domestic plant from the tropical swamps but also a plant that the students study in school and college labs and the scientists make new discoveries.
   The tradescantia improves a room just fine if it is suspended in a beautiful basket or a special ceramic pot container before a window or even under a lamp in the middle of a room. Its twigs with green or striped leaves will elegantly droop downwards. The tradescantia is an irreplaceable plant for wall vases. It's enough to put its' twig into a vase, and it will spread roots and for several months it will live and grow even in pure water.
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