The club-shaped clown (Latin Lycopodium clavatum) is found in pine and mixed forests. Thin evergreen grassy shoots crown dense spikelets. But this is not an inflorescence, because the plun is the highest spore plant and never blooms. Reproduction and the life cycle have peculiar features associated with the ancient origin of the whole group. The structure of the mace is club-shaped.
Living fossils
In the Paleozoic era, forests of tree horsetails, plunders and ferns covered vast spaces on the planet. Over time, these groups of organisms, for the propagation of which need water in a drip-liquid form, have given way to more adapted plants - gymnosperms and flowering. Tree-like clowns - lepidodendron and sigillaria, which reached a height of 40 m did not survive in this struggle for existence. But it was they who gave rise to powerful coal seams in some regions of the planet. Modern plants of the Plaunova family are not similar in appearance to lush carbonaceous vegetation, but they inherited the method of reproduction and the development cycle of their ancient ancestors.
Why is the plant called "plun"?
Creeping green stems begin to grow from the original place of attachment of one of the stages in the life cycle of the plunger - a sprout. Along the perimeter they are still young, without spore-bearing spikelets, and in the central ring they have outlived their own. It seems that the club-like clown moves through the forest. This is due to the constant withering away of old shoots and the growth of new ones. A feature has long been noticed by the Slavic peoples and gave the “floating” plant the name “plun” (quicksand). The origin of the Latin name for the genus of the pluno is interesting. It is associated with the German word "wolf paw." So in ancient times, the plaun was called in Germany. In the XVI century, the word was translated into Latin, resulting in Licopodium. Different peoples call the plun "lycopodium", "dereza."
Features of the pluns
Peculiar and very ancient plants are found in the forest zone of the Northern and Southern Hemispheres. The genus Lycopodium, to which the club-clown belongs, existed in the Paleozoic forests over 350 million years ago. Many signs indicate that this group is gradually dying out. But in the structure of the plunas there are features of a higher organization compared to mosses. You can get acquainted with them by the example of a club-shaped club.
The oldest signs:
- dichotomous branching;
- spiral leaf arrangement.
Features of higher plants at the plun:
- differentiated tissues;
- leafy grassy stems;
- real roots.
A characteristic feature is microphilia associated with the origin of leaves from superficial stem outgrowths.
The structure of the clan club-shaped
The entire perennial plant (asexual stage) looks fluffy from many deviating small leaves. They have a linear lanceolate shape, each ending in a white extremely brittle hair. The club-shaped clown has a long and thin creeping stalk. This peculiar live cord reaches a length of 1 to 4 m. From it, lateral ascending shoots (50 cm) originate. There is no core root, there are only subordinate, with which the plant is attached to the ground. Long thin legs with sparse leaves lead from the stem to the thickenings on top of the shoot. These are spore-bearing spikelets having a cylindrical shape and reaching a length of 4 cm. Usually collected in two, less often found in groups of three or four. Sporangia are placed in the sinuses of sporolorists. Each of these sacs is filled with small spores.
Gametophyte structure
Spores of the club-shaped clown give rise to a gametophyte, or sprout. The structure of the clavate club at this stage is completely unlike a perennial plant, as we used to see it. The sporophyte reaches a diameter of just over one millimeter. This growth is a temporary phenomenon in the life of the plant, but very necessary. If the spores are in adverse conditions, then for a long time they cannot give rise to a new organism. Microscopic gametophyte cannot independently absorb nutrients; it uses the “services” of soil fungi. If spores quickly germinate on the surface, then the translucent overgrowth acquires a pale green color and is capable of photosynthesis. In favorable conditions, the gametophyte matures faster. Sexual gametes occur in special formations. Female - ovules - large and motionless. Male - sperm - small, equipped with flagella and move quickly. Sex cells mature at different times. Male cells need droplets of water to move to the eggs. When gametes merge, fertilization occurs. The zygote begins to divide, giving rise to cells and tissues of the future sporophyte.
Club life
Let us trace the
development of a plant from spores to an adult plant. It is he who we usually see in the forest or in the photo "The club-shaped clown". In summer sporangia sacs of spikelets, a huge number of spores ripen, resembling yellow powder. It is possible to examine the structure of dust particles only under a microscope. Chemical analyzes indicate a significant content of vegetable fat in them. Disputes are poured in July-August, are carried by the wind through the forest and serve to spread the clown. Under favorable conditions, germination begins in the soil. A gametophyte sprout is formed, resembling a small pea with a tail.
The sexual reproduction of the club-shaped clown is an intermediate stage in the life cycle, providing genetic diversity. After the formation of gametes and fertilization, a microscopic sporophyte appears on the growth. In its structure, one can already see the thin green stem and leaves. The shoot rushes towards the light, and the spine - down into the soil. More often, a clown
multiplies vegetatively - each of its lashes, which has roots, is able to survive without a mother plant.
Practical use
For medical purposes, spores of a plant known as Lycopodium are used. It uses raw materials collected in natural conditions for the preparation of baby powder and anti-pressure sores. Lycopodium contains:
- butter;
- proteins;
- polysaccharides;
- sitosterol;
- phenol carboxylic acid;
- minerals.
Folk healers appreciate the healing ability of lycopodia, recommend for burns, frostbite. The grass has anti-inflammatory properties and is used for diseases of various organs and systems. External forms of medications from the spores of the ploon help with eczema, boils, lichens. Treatment with the preparations of the plung should be carried out on the recommendation and under the supervision of a doctor.
Environmental requirements
The stems of the plow gradually “sprawl” away from the original spore germination site. The ability to form them in a plant appears in the 15-30th year of life. Growth dies at the stage of formation of shoots and roots. The structural features of the club-shaped clown and its reproduction predetermined the distribution of the plant. Undemanding to soils, it needs droplets of water for fertilization at the sexual stage. Such conditions are found in many regions and countries, including Russia, Belarus, Ukraine. The plant is found mainly on sandy soils in light pine forests. Less often - in mixed and deciduous. In the last half century, the number of plunas has decreased significantly. One of the problems of resuming the range is associated with the slow formation of spore-bearing spikelets. In forests, vegetative shoots can be found much more often than generative ones. In addition, suitable conditions for the germination of spores are not always found. They can die from drying out or for years not give rise to a gametophyte. This is only part of the environmental issues associated with the oldest plant on Earth. It can repeat the fate of the planetary neighbors in the far Paleozoic - lepidodendron and sigillaria.
Deforestation, their conversion into agrolandscapes adversely affected the sexual and asexual reproduction of the club-shaped clown. Its protection is carried out in a number of US states, where the plant is recognized as rare, in need of protection.