Scientific work on the theme of cacti. Research work on the topic "Why does a cactus need thorns?"

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Research“Cactus is a prickly friend” The work was completed by: Yarullina Adela Faizovna, student of the 4th “A” class of the city of Nurlat RT MAOU “Nurlat Gymnasium” Teacher: Yakovleva Svetlana Nikolaevna

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Work plan: 1. Introduction 2. Purpose and objectives 3. Main part 4. What is a cactus? Cacti near us 5. Transplanting and propagating cacti 6. How to grow a flowering cactus 7. Poems about cacti 8. How to issue a passport to cacti 9. Conclusions 10. Prospects for further research 11. Use of the project 12. Literature used

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When I was 7 years old, I came to work with my mother in Kindergarten. My attention was drawn to the cacti that stood on the windowsill, on the cabinets, high on the shelves and green lashes freely descended. Cacti struck my imagination with a variety of shapes and sizes, original thorns, flowers of amazing beauty. I fell in love with cacti, noticing my delight, my mother gave me a crumb - a cactus.

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Cactus The word "cactus" comes from the Greek "cactus", which in ancient Hellas called plants with thorns. Cacti came to Europe after the discovery of America. They belong to the family of dicotyledonous, perennial plants, usually with fleshy, succulent stems. With their well-developed root and fiber system, they draw moisture up to 147 bar. Cactus leaves are replaced by spines, hairs and bristles. This is a good defense against those who want to enjoy the juicy pulp of the plant. The color of the spines changes with age and is an adornment of many types of cactus. Over 3000 species of these plants are distinguished in the world. There are tree-like, shrubby and liana-like cacti. They can be found in arid deserts, on bare impregnable rocks, near the seashore.

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Plants can be propagated different ways: seeds, layering, cuttings. The simplest and fastest in time is reproduction by “kids”. Cacti themselves will tell you when it is better to transplant them. As a rule, this happens in the spring once every two years, when they began to grow, their tops climbed. At this time, it is necessary to increase watering and prepare an earth mixture consisting of 2/3 of the earth with a small amount of fertilizer 1/3 of the sand. A few days before transplanting the cactus, it is better not to water it, then the earthen lump is easily removed from the pot, and the small roots remain intact. Cacti are flowering and non-flowering. I was more interested in flowering cacti. These include: Echinopsis, Mammillaria, Parody Rebutius, Gymnokamentium. At proper care cacti bloom annually and even twice a year. So I decided to awaken flower buds to life. And this experiment worked for me. To do this, in the spring I planted two cubs from one Echinopsis cactus into different pots and began to care for them, put them in the light, watered them with water at room temperature at certain times in summer and winter, fed them, strictly maintained a dormant period that lasted seventy days . In December, for one cactus, I stopped the current care, moved it to the shady side, stopped watering, feeding, planting children, left it at rest for about two months. She continued to take care of the first cactus as before. In March, I noticed that he grew noticeably, spread out in width, children began to appear.

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In September, a bump appeared on my "second" cactus, it gradually grew over three days, then stretched out into a tube, The tube stopped growing, but its end began to thicken and suddenly opened

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This is what the flower looked like on the second day. There was no limit to the joy that the experiment was a success, I even invited my girlfriends to look at this miracle, how long I had been waiting for it, and everything happened. We even took pictures with a blooming cactus. It bloomed for exactly three days. I also noticed that the Echinopsis flower has a long tube and grows from the side, this is its feature, as I later read. On the fourth day, the tube became thinner, lost its elasticity, and on the fifth day it fell off completely. On the first cactus, the flower did not appear. Only now he has become very large, important and prickly, living in my house today. Creating favorable conditions for the flowering of a cactus at home, I acquired a lot useful information about cacti and came to the conclusion that even a flowering cactus variety blooms only under certain conditions.

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Now I am taking care of two more cacti and will continue my research in the future, as this work has interested me and fascinated me.

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I had to visit a flower exhibition, where I noticed that each cactus has its own passport, in which the name of the family is written, like the surname and name of the plant in Russian and scientific in Latin. Its homeland and place of growth, signs of longevity, plant number and care. I also made a passport for my cactus.

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Echinopsis / Echinopsis Sem. Cactus "Cactacae" Homeland - South America. Biology - succulent "juicy". Care: location - bright, sunny, loves warmth in summer, coolness in winter. Humidity is low. Watering when the soil surface dries out, in winter - economical. During the flowering period, feed, spray regularly with water. Humus, clay-soddy soil, sand "1: 1: 1". Reproduces by children.

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Cereus Peruvianus (monstrous form) / Cereusperuvianusf. monstrosa Fam. Cactus (Cactacae) Motherland - South America Biology - succulent Care: undemanding to conditions. All year long in the bright sun Leaf and sod land, weathered clay, coarse sand (2:2:1:2) Vegetatively propagated.

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Prickly pear /Opuntia azurea Fam. Cactus (Cactacae) Homeland - South America Biology - succulent Care: location - bright, sunny, loves heat in summer, coolness in winter. Humidity is low. Watering when the soil surface dries out, in winter - economical. Spray regularly with water. Leafy and soddy soil, weathered clay, coarse sand (2:2:1:2) Propagated vegetatively.

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Mammillaria / Mammillaria elongata Fam. Cactus (Cactacae) Homeland - Mexico Biology - succulent Care: location - bright, sunny, loves heat in summer, coolness in winter. Humidity is low. Watering when the soil surface dries out. Leaf, sod, peat soil, sand, brick chips (1: 1: 1: 1/2: 1/2) Propagated vegetatively.

Hypothesis my research: if cacti grow in natural environment in warm countries, then you can grow them at home in Siberia from
seed.

Object of study: cactus.

Purpose of the study: grow a cactus from a fruit seed at home in Siberia.

Research objectives:

• learn the history of the cactus;
• grow a cactus from a seed;
• find out what my classmates know about cacti.

Research methods:

• search for information on the Internet and literature;
• monitoring the growth and development of a cactus.

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Introduction

Cacti, perhaps, have lost some of the popularity they enjoyed about fifty years ago. They no longer top the lists of the most purchased plants, but they can still be seen in millions of homes, and they are still the most misunderstood of all indoor plants.

It is generally accepted that cacti do well if they are not cared for at all. There is hardly another living organism that can be placed in a house in such bad conditions as a cactus, and it still outlasts the owner! Therefore, millions of slightly living cacti throughout the country have been kept for years as green decorations, outwardly almost unchanged and only slightly increasing in size. Well, how! After all, everyone knows that cacti in nature live in the desert, perfectly tolerate drought and constant heat, and with luck, bloom once every seven years.

All this is not so! An abundance of fine-grained sand can actually kill cacti. The summer heat will put them into hibernation. For normal development and regular flowering, they need such a winter temperature that makes a person shiver, and in summer many of the cacti would prefer open air to overheated stuffy rooms.

Now, when almost every office, home has computer equipment, there is an opinion that the cactus helps to protect yourself from all kinds of radiation coming from the computer, but there is a second opinion: cacti grow much better when they are next to the computer.

So what kind of plant is this cactus, and how to take care of it so that it becomes “alive” and helps us avoid radiation (if there is one)?

Based on this, we have chosen the topic of our work "Cacti and computers".

The purpose of the study was the study of literature on cacti and computers and the experiment of growing a cactus near a computer.

Object of study: the process of growing a cactus near the computer.

Subject of study: conditions affecting cactus growth.

Hypothesis: near the computer, the cactus grows faster.

Tasks:

1. To study the available literature on the topics: "Cacti", "Computers".
2. Conduct an experiment to establish a connection between a cactus and a computer.

Research methods:

• Analysis of scientific literature;
• Conducting an experiment;
• observation.

Chapter 1

Cacti belong to the group of perennial plants that can store and retain water for a long time. There are over 3,000 types of cacti on earth. Their homeland is Mexico. The ancient Indians considered them sacred. Cacti gained fame in Europe only in the middle of the 15th century, after the discovery of America. Even Eastern civilizations, tightly closed to Western influences, made an exception for cacti. Already at the end of the 17th century, these plants are mentioned in Japanese and Chinese literature. In 1867, the first cactus exhibition was held in Japan, at which 48 species were exhibited, and unusual, unnaturally colored cacti were also bred.

It is believed that the London apothecary Morgan was their first collector. The peak of interest in Central American and Mexican cacti: echinocereus, mammillaria, prickly pear falls on the first half of the 18th century and then gradually subsides. Since the beginning of the 19th century, large collections have reappeared, made up of collections in nature, expeditions specially sent for cacti. At the same time, societies of lovers of these plants were created and special magazines devoted exclusively to cacti began to be published. Since the end of the 19th century, the cultivation of cacti has ceased to be the privilege of a few amateurs; even inexperienced flower growers are trying to widely cultivate them. Before World War II, Bolivian, Argentinean, Peruvian and Chilean cacti began to enter the European collection - types of lobivia, rebutia, parodies.

As for Russia, here rich people became interested in cacti. Interest was fueled by the high price and rarity of these plants - cacti adorned the most brilliant European palaces.

In Russia, during the time of Alexander I, a special expedition was organized to America for cacti. And a special connoisseur and truly fan of cacti, Prince Viktor Pavlovich Kochubey, who financed this expedition, was presented with three copies of a completely new, unlike anything plant.

The prince gave one copy to the St. Petersburg Botanical Garden, left the other in his collection, and sold the third for an absolutely fabulous amount of gold - the weight of this gold was many times greater than the weight of the cactus itself.

This deal was one of the most expensive in the history of cacti growing. Cacti have truly conquered the world - they are collected and eaten, they decorate the house and even are treated.

Cacti are very different - tree-like, shrubby, herbaceous. Some look like a hedgehog, others look like a pumpkin, others look like a candlestick. There are crumbs of 1 cm and giants of 25 m. Babies weigh a few grams, and giants weigh tons. The flower of the cactus "Queen of the Night" has a length of each petal up to 14 cm.

For us, cacti are decorative houseplants. When caring for them, you need to know their individual characteristics. So, in summer, plants need a lot of water. Some in the hot season stop their growth (this is noticeable in their appearance), and they need to be watered very rarely. With the onset of cool autumn days, watering is gradually reduced. In winter, most cacti are kept at a temperature of 8 - 10 ° C. Watering in the cold season should be no more than 2-3 times a month, avoiding complete drying. Cacti wintering in warm rooms are watered more often. Such plants, not receiving winter rest, are depleted and do not bloom. Spring cacti require much more water. It is better to water early in the morning with boiled or settled tap water at room temperature. On cold days, the water is slightly heated. Excess and stagnant water in pots can lead to rotting plants.

Most cacti are very light-loving. Therefore, it is better to keep them on the balcony or in the window box, covering the plants in rainy weather with plastic wrap. In the hours of midday heat, the plants shade. In winter, it is better to put cacti on a light window sill between frames or on a window sill, which is protected from room heat with film or glass.

The soil for cacti is coarse-grained, loose, quite nutritious, without undecayed organic residues. Cacti are propagated by sowing seeds and cuttings - reproduction by parts of stems or individual processes - by children, which are cut from the mother plant in spring.

Thus, having studied the literature on cacti, we came to the conclusion: the cactus plant is whimsical and in order for it to bloom, a lot of effort must be made

Chapter 2. Cacti and computers.

Humanity born in the environment flora, since ancient times learned to use its beneficial properties. To date, extensively studied beneficial features tens of thousands of plants that help almost all known diseases and ailments. But the change in the human environment poses new challenges, and, simultaneously with the massive appearance of computers, the search for plants began that would help protect against radiation.

As numerous studies have shown, almost all types of cacti are "friends" with computer technology. The experts of the Center for Electromagnetic Safety have developed the requirements of sanitary standards. But there are simpler solutions - just put a pot of cacti on both sides of the equipment, and you will feel much better - electromagnetic radiation will not hurt you, these exotic thorns will "eat" them. The presence of a cactus in the room has a beneficial effect on a person.

Scientists believe that the healing properties of cacti are due to their excellent adaptability to survive in conditions of increased radiation in their distant homeland - in the highlands of Peru and Mexico.

In addition, the Business Ecology article states:

“Cacti help to protect yourself from all kinds of radiation. It turns out that they have a remarkable ability to "absorb" rays that negatively affect our body. Therefore, in the West last years Cultivation of cacti right in front of a computer monitor has become a kind of hobby.

It is especially important to breed plants in offices and apartments with outdated types of computers and monitors that do not have protection. Apart from everything else, it is also very beautiful. By the way, scientists have noticed that cacti grow better in computer rooms and bloom more often.

Chapter 3. Experimental work

Experiment status: experiment done at home.

The purpose of the experiment was: to compare the process of growing a cactus near a computer and on a bookshelf.

Research methods:

• Study of scientific literature;
• Observation;
• Creation of favorable conditions;

Experiment timeline:

• Start time: 18.08.09
• Estimated completion time: 02.02.10.

Description of the experiment:

On August 18, 2009, we placed cacti of the same length and age in the same room. One flower was placed near the computer, and the second on the bookshelf. During the period from 18.08.09. until 02.02.10 watching the growth of plants. 05.11.2009 a barely noticeable "daughter" appeared on the tip of the cactus standing near the computer. During from 05.11. until 02.02. her height increased and reached 5cm. And the cactus itself, standing near the computer, also grew by 2 cm.

The cactus standing on the shelf remained unchanged.

As a result of the research, the following output : The cactus located near the computer grows faster than its counterpart growing on the shelf.

CONCLUSION

Analysis of the literature and work experience allowed us to draw the following conclusions:

In order for the plants to feel “at home” in the room, it is necessary, first of all, to know the basic requirements of each of them for humidity, light, temperature and soil. All this mainly depends on the origin of the plants in which they grow in their homeland.

We must immediately abandon the common misconception that any plant can grow in any room - you just need to water it regularly. It should be firmly remembered that each plant is a specific organism with its own “character”, its own requirements for conditions. external environment. In addition, a cactus is a plant and, like any plant, it requires care. And it is not so important where the cactus stands, the main thing is to care and love the plant, and it will surely repay you in the same way in the form of a beautiful flower.

Based on our experience, we want to support scientists who noticed that when growing a cactus on a monitor, the plant is fed by radiation and heavy ions, which favorably affects its growth.

Bibliographic list.

1. Klevenska T.M. "Flowers in the interior" - Moscow, 1990
2. Lobko V.D. "Your greens."
3. "Computer cacti".
4. Great Encyclopedia of Cyril and Methodius 2009
5. "Cacti". - Rostov n/a, 2002
6. Encyclopedia for children. Biology.
7. A book for flower lovers. - M., 2000
8. Hession D.G. All about indoor plants - M., 2002
9. "What's happened? Who is this?”: Vol. 2 - 4th ed., revised. and additional - M.: Pedagogy-Press, 1999.
10. Internet.

Their spines are of great variety. There are sharp, like needles, while long and short. Curved and hook-shaped, hard and soft, radiant and twisted into balls, feathery and hairy, more like down. All varieties and not to list. But, regardless of their external structure, they play a primary role in the life of plants of the family.

First of all, they serve to absorb moisture. Indeed, in those places where these unusual grow, for long months, and sometimes for years, there is no rain. As a rule, during the day there is a sharp temperature drop. At the end of the night it can be only a couple of degrees of heat, and in the middle of the day the air heats up to + 40-50 degrees. Naturally, under such conditions, intense condensation of water vapor occurs with the formation of abundant dew. It is precisely dew that serves as the main source of moisture.

Cacti are able to absorb water with the entire surface of the stem, but the spines do this especially intensively. They are modified leaves that resemble microscopically thin tubes that actively absorb the slightest moisture. Yes, one drop will not get you drunk. But there are thousands of spines on one adult cactus! And each in the morning produces its own drop of dew. As they say, with the world one by one, that is, drop by drop, so I quenched my thirst.

Of course, to some extent, thorns also serve for protection. But, on reflection, it is not difficult to guess that in those places where it rains every few years, animals are unlikely to be able to live. Therefore, there is no one to defend against. In such regions grow cacti with soft and thin spines that do not pose a particular danger.

Cacti with large and sparse spines that do not cover the stem at all are inhabitants of grassy places. It is clear that these spines cannot actively water or protect from the scorching sun. Yes, and there is no need for this when there is a lot of grass and shrubs around, giving a fertile shade. And there is enough moisture here for a normal life. The dry period is always followed by the rainy season. Therefore, such thorns are quite impressive in size and serve solely to protect against herbivores. Hard and sharp, they discourage the desire to taste such a cactus for a long time.

Another task of the spines is to protect the stem from the scorching sun. In some species of cactus, the spines cover the stem so tightly that it is almost invisible. And there are species covered with thick white fluff, reminiscent of luxurious fur. And White color here it is not at all accidental: after all, its ability to effectively reflect light is well known. All this helps to avoid fatal overheating in the sun. And on a cold night, such a fur coat will protect from the cold, when sub-zero temperatures are not uncommon in these places.

They also serve as decoration to attract cactus lovers. I know it sounds funny, but cactus lovers will understand. For the variety of shapes, sizes and shades of cactus thorns is simply stunning. I will give just a few examples. The spines of Mammillaria plumosa cannot help admiring - this beauty is simply beyond competition!

Mammillaria lasiacantha can showcase a whole group of plants with feathery spines. What do these look like? Thin rays of numerous spines diverge from the areoles, each of which individually resembles a feather in its structure.

Photo: I. Lukyanchik, personal archive

And Mammillaria bocasana in her white downy coat is just charm itself, the Snow Maiden, lost in hot latitudes. By the way, about the snow. Impressive Mammillaria egregia, perfectly covered with snow-white spines, reminiscent of openwork snowflakes. I think these descriptions are enough to imagine the unique beauty of these creatures.

The world of cacti is large and diverse. For centuries, these amazing plants have been adapting to the extreme climatic conditions that arose in their habitats. And as a result, these plants, having neither branches nor foliage, were able to learn how to live and successfully solve the problem of obtaining, accumulating and rationally using life-giving moisture every day. I think they deserve our admiration.

The main functions of leaves are photosynthesis and water evaporation. In order to perform these functions most effectively, the sheet must be in the form of a plate, that is, it must have a large surface and be thin. These are the leaves of most plants. However, in some plants, the leaves in the process of evolution have changed (have undergone changes) and become unlike ordinary leaves. The reason for this phenomenon is that the leaves began to perform other functions not related to photosynthesis and evaporation.

The leaves of a number of plants in arid habitats have evolved into spines. Such leaves, on the one hand, almost do not evaporate water, on the other hand, protect plants from being eaten by animals. An example of plants of desert places with thorns are various cacti. Their photosynthesis proceeds in the cells of the thick stem located closer to the surface. The stem also stores water. Thus, the leaves modified into spines lost both of their main functions (photosynthesis and evaporation), but instead began to perform a protective function.

Spiny leaves can be observed not only in plants of deserts and semi-deserts. Barberry, rose bushes, wild rose, etc. have spines. However, in these plants, not all leaves are modified into spines, but only some. At the same time, the function of the spines here is the same as that of cacti - protection from being eaten by animals.

The leaves of other plants in arid habitats have adapted to the lack of moisture in a different way. So in aloe and agave, the leaves have changed into thick and juicy formations in which water is stored. And to reduce evaporation, such leaves are covered with a wax coating, hairs, and have fewer stomata. In this case, the leaves have changed so that they have not lost their main functions, while acquiring an additional one - storing water.

There are plants whose leaves are modified to antennae. With these tendrils, the plant clings to the support and is held in an upright position. An example of plants with tendrils are peas, chin, vetch and other legumes. In peas, the upper parts of the leaves are turned into antennae.

In nature, there are insectivorous plants. Their leaves are modified into peculiar trapping devices. When an insect sits on a leaf of a sundew plant, it sticks to it, because the leaf is covered with hairs that secrete a viscous mass. After that, the hairs and the leaf itself are folded. Inside the resulting cavity, the insect is digested due to the enzymes secreted by the leaf. Sundew assimilates nitrogen-rich organic matter from the insect. It is precisely because of the lack of nitrogen and other trace elements in their habitats that sundew leaves have acquired such a specific function.

Another modification of the leaves are scales. In this case, the scales are different, because they perform various functions. For example, in an onion in a bulb, the leaves are turned into juicy scales, in which a reserve is deposited. nutrients. Other scales cover the kidneys. In this case, they perform a protective function.

* This work is not a scientific work, is not a final qualifying work and is the result of processing, structuring and formatting the collected information, intended to be used as a source of material for self-preparation of educational work.

Cacti are perennial succulents of the cactus family. Mostly inhabitants of deserts and semi-deserts of the American continent.

The leaves of cacti are reduced and replaced by spines in most species, the stems are capacious water reservoirs. All cacti have areoles (axillary bud metamorphosis), from which flowers develop, "children" of cacti grow. A peculiar appearance, combined with a very beautiful flowering, has made these plants very popular among lovers of indoor floriculture. The following species and groups of species are recommended for room culture.

Peyrescias have true leaves and grow into large shrubs, often serving as rootstocks for grafting cacti with weak roots onto them.

Prickly pear are characterized by flattened articulations of the stem and areoles, on which, in addition to spines, very sharp small bristles (glochidia) develop, which easily pierce skin and clothing. However, they are often very decorative (for example, in varieties of finely pubescent prickly pear).

Cereus are distinguished by columnar faceted stems, in different species originally pubescent with long or short hairs, or naked and bluish (cereus, cephalocereus, espostoa, oreocereus, lemereocereus, trichocereus).

The group of "blackberry" cacti covers a wide variety of genera, which are characterized by a rounded shape and many spines (hence the name). For breeding in rooms, we can recommend Echinopsis, Echinocactus, Echinocereus, Rebutia, Ailostera, Lobivia and Pseudo-Lobivia, parody, hymnocalycium, ferocactus, hamatocactus and many others.

Mammillaria - a group of papillary cacti; differ in a variety of shapes and spines. In Mammillaria, the tubercles (papillae) are arranged in a spiral around the stem, and the flowers arise between the areoles on the tubercles.

Unlike the above species, epiphyllum, ripsalis, epiphyllopsis, ripsalidopsis and zygocactus are forest cacti. Most of them are epiphytes, so in room culture they develop better when grafted (for example, on Peyres). These are shade-loving plants, they do not tolerate direct sunlight. In winter, they require constant moisture. They should be planted in loose humus soil with an admixture of sand and coal.

All desert cacti can be cultivated in soil composed of soddy and leafy soil with the addition of river sand, broken bricks or shards, chalk and charcoal. These are photophilous plants, they need the maximum number full sun and grow very well outdoors. In winter, cacti should be kept in a cold (from -6 degrees to -8 degrees) and always dry place. From October to March, cold wintering cacti should not be watered, then they bloom intensively. The best way watering - immerse the pots with plants in water until air bubbles stop, and then dry them well. The bottom of the pot must be covered by 3-4 cm with a layer of small shards. In young plants, the need for moisture is higher, so in winter they need to be watered once a month and ensure that the earth does not dry out and does not turn into dust. It is difficult to dry adult cacti, and they easily rot from excess water. Reducing watering in winter does not yet give the cactus the desired dormant period.

For this, it is necessary low temperature, which is easy to achieve by fencing off the window sill with cacti on it from the room with glass or plastic wrap.

Sowing cacti requires special attention. It is necessary to sow the seeds in washed river sand, mixed in half with leafy soil, slightly pressing the seeds. Before the emergence of seedlings, it is advisable to keep the crops at a temperature of 25-30 degrees and spray only from a spray bottle. At first, crops should be covered with glass. Small shoots should be dived several times so that they develop better. In the first year, they should not be dried out, kept in too bright sun or in drafts.

It is easier to propagate cacti from cuttings. Cuttings should be cut with a sharp knife, sprinkled with sulfur or coal and left to dry for 3-4 days. Cuttings should be rooted in washed river sand (preferably heated). As soon as the roots are formed, and the cuttings begin to grow noticeably, they can be planted in a small dish. 3-5 days before transplanting, watering the cacti should be stopped so that the earth ball dries up and the earth easily separates from the roots. After transplantation, the plant must be placed in the shade and not watered for 5 days, so that the roots accidentally injured during transplantation do not rot. Best time for transplantation - spring. In order not to prick your hands, cacti during transplantation should be kept with a strip of sufficiently dense paper folded several times.

Cactus adaptations to environmental conditions.

Spreading. Homeland cacti - continental and island America. They are found from Canada to Patagonia and Tierra del Fuego and from the Galapagos Islands to the West Indies. Mexico is richest in species and life forms of cacti. In the USA, cacti are especially abundant in Texas, Arizona, and New Mexico, although the natural range of the family covers almost all states, with the exception of Hawaii, where cacti have become naturalized after the introduction. Thinly branched epiphytic cactus Rhipsalis grows wild in western Africa, Madagascar and Sri Lanka.

Chemistry, Biology, preparation for the GIA and the Unified State Examination

It is believed that it was brought there in ancient times by birds or humans.
Origin: The ancestors of cacti were, most likely, rather moisture-loving plants with well-developed leaves, possibly lianas. As a result of geological processes, the climate in the places of growth of ancient cacti has become much drier. Plants that failed to adapt to the changed conditions died out, and cacti survived due to partial or complete reduction of leaves.
Adaptations.

The cactus tries to absorb as much moisture as possible and store it for a long time. And then very slowly consumes it. So, the cactus must increase its volume in order to store more water, but must decrease its surface area in order to reduce evaporation. It is known from mathematics that a geometric body that has largest volume at the smallest surface, is a ball. Therefore, cacti are most often found spherical.

The function of the leaves is performed by a green stem of a round, squat or elongated cylindrical shape, ribbed, flat like a leaf or elongated like a vine. They took over the main function of the leaves - photosynthesis.

The giant carnegia cactus lives 150-200 years, sometimes reaching a weight of 7 tons. spread wide root system located at the very surface of the soil. This is probably why there are no other cacti within a radius of 15-20 m. The resistance of carnegia to adverse environmental conditions is amazing: for more than a year, for example, it can be without water, and lateral shoots continue to bloom even after the death of the main trunk. The trunk of the carnegia is quite dense, and some species of woodpeckers gouge hollows in it, in which other species of birds can nest in the future.

Organisms adapt to the same environment often in different ways. General and different adaptations of shark and dolphin.

Output: adaptations of organisms appear as a result of the action of the driving forces of evolution (the struggle for existence, natural selection, hereditary variability). So the natural selection of their entire variety of non-directional hereditary changes selects and fixes only those that provide the population or species as a whole with optimal adaptations to given conditions of existence .

The relative nature of fitness.

The adaptability of organisms to the environment has been developed in the process of long historical development under the influence of natural causes and not absolute, but relative, since environmental conditions often change faster than adaptations are formed. Corresponding to a specific habitat, adaptations lose their meaning when it changes. Proof of the relative nature of fitness may be the following facts: protective devices from some enemies are not effective from others (for example, poisonous snakes that are dangerous for many animals are eaten by mongooses, hedgehogs, pigs); the manifestation of instincts in animals may turn out to be impractical (moths collect nectar from light flowers, clearly visible at night, but they also fly to the fire, although they die at the same time); an organ that is useful under certain conditions becomes useless and even relatively harmful in another environment (the membranes between the fingers of mountain geese, which never sink into the water); better adaptations to a given environment are also possible.

Adaptation to the environment is relative, useful only in the conditions in which it was historically formed. When these conditions change, adaptations lose their value or even harm the body.

Where do cacti grow?

Cacti, or simply cacti, are perennial flowering plants. It is generally accepted that they evolved about 40 million years ago. Then Africa and South America were already separated from each other, and North America not yet connected with the South.

Despite the fact that no fossil remains of cacti of those times were found, it is believed that they first appeared in South America, and only 5-10 million years ago came to the northern continent.

Where do cacti grow in nature?

To this day, cacti in wild nature grow mainly on the American continents. It was from there that they were once transported by people and carried by birds to Europe.

However, representatives of cacti in nature can be found not only in America. Some species have been growing for a long time in the tropical part of Africa, in Ceylon and other islands of the Indian Ocean.

Where else do cacti grow: thickets of this plant can be found in Australia, the Arabian Peninsula, the Mediterranean, the Canary Islands, Monaco and Spain. Cacti grow wild in the territory of the former Soviet Union. In most cases, cacti in these places were artificially brought by man.

Conditions for the growth of cacti

Basically, cacti prefer steppes, deserts and semi-deserts. Sometimes they can be found in tropical rainforests. Quite rare, but they still grow on wet coasts.

In Mexico, cacti grow in sagebrush, creosote, and also in high-altitude succulent deserts. In the high deserts, cacti are concentrated mainly on the Mexican plateau, as well as in the western and eastern parts of the Sierra Madre.

In what deserts cacti grow: cacti quite extensively and densely inhabit the deserts of Peru, Chile, Bolivia and Argentina. There is a rich diversity of these plants.

In which countries do cacti grow?

If we indicate the geography of cactus growth by country, the list will be approximately as follows: Mexico, Brazil, Bolivia, Chile, Argentina, USA (Texas, Arizona, New Mexico), Canada, China, India, Australia, Spain, Monaco, Madagascar, Sri- Lanka, West Africa.

As ornamental plants, people have learned to grow cacti in open ground almost everywhere, with the exception, perhaps, of the Arctic. As indoor plants, cacti have long populated the entire planet.

One of the serious but controversial reasons for the appearance of cristats in cacti some scientists consider viruses and bacteria.

As a more important and possible factor in the appearance of such formations, the mechanism of heredity is currently called. Indeed, the seeds of monstrous cereus, echinopsis, parodies, chamecereus give part of the seedlings of a normal structure, and some of them are ugly. On the other hand, among seedlings from non-monstrous cacti, crests may spontaneously form. Apparently, cacti have a hereditary tendency to crystallize, which manifests itself under certain conditions. Such conditions, as suggested by G. G. Volsky, can be an increase in moisture or nutritional value of the soil. Another form of malformed growth are the so-called rock cacti. Here, probably, we can talk about the incorrect formation of side shoots, some of which become long, while others remain short.

Areoles, spines. Areoles - limited small areas on the stem of cacti, where spines, hairs, flowers, fruits, lateral shoots develop - babies. A cactus can be easily distinguished from another succulent plant, often very similar to it, precisely by the presence of areoles. The latter are modified axillary, or lateral, kidneys. The size and shape of the areolas are different. In most cacti, the upper part of the areola produces flowers and vegetative shoots, while the lower part produces spines. In some representatives belonging to the group of papillary cacti (mamillariaceae), the growth point of the areola in the early phases of development is divided into two. In this case, in one part of the areola, located at the top of the papilla, spines develop, and in the other, located in the axil of the papilla, or axilla, flowers and children are formed. If such separation of the areola occurs at a late stage of development, as in Coryphantha, then a groove forms between the two parts of the areola.

What is a thorn? Through the work of many scientists, it has been proven that the thorn of a cactus is of leaf origin. This is evidenced by the presence of intermediate forms between the spine and the leaf, the entry of vascular cords into the spines, the formation of spines from the same tissues as the leaves, the cases of finding chlorophyll in some spines, etc. However, it is not entirely correct to say that the spines are modified cactus leaves. After all, the latter are initially laid on the top of the plant in the form of small tubercles, but do not develop further. Therefore, spines should be considered as modified kidney scales (recall that the areola is a modified kidney). Since the areola remains active all the time, more and more spines can appear in it, in addition, the spine itself can increase due to the growth of its lower part. The size, shape, location, color of the spines are different. According to their location, they are divided into central and radial. The central ones are usually smaller than the radial ones, they are longer, thicker and often have a hook at the end. Young spines are usually soft, brightly colored, and pubescent. Sometimes the spines change greatly, becoming flat, flexible, "papery" ( Tephrocactus articulatus var. papyracanthus) or bristle-like ( Opuntia leucotricha). The length of the spines varies from 1-2 mm to 24-25 cm ( Cereus jamacaru, Corryocactus brevistylus). In addition to spines, soft thin hairs can form in the areoles, often almost completely covering the plant ( Cephalocereus senilis, Echinocereus delaetii, Mammillaria bocasana and etc.). An interesting formation, inherent only to prickly pear, are glochidia. Unlike spines, they are very fragile, covered with numerous microscopic hook-shaped outgrowths, and arranged in a bunch in the areola. At the slightest touch to the glochidia, they easily break off, digging into the skin.

The nectar-bearing spines found in the hamatocactus bristle-prickly are peculiar ( Hamatocactus setispinus), in representatives of the genus Coryphantus and Ferocactus. They secrete nectar to attract pollinating insects.

What are the functions of spines? One of the most important is the ability of spines to condense water vapor. Spines, due to the peculiarity of their microscopic structure, have the properties of a capillary. For species with a poorly developed root system (for example, in disco cacti), they are the main organ of water supply. The hairs on the stem of astrophytums, consisting of cells penetrated by tiny pores, actively absorb moisture. The spines protect the cactus, especially its young parts, from the scorching rays of the sun during the daytime and from the cold at night, from being eaten by animals and from mechanical damage. The spines on the fruits also contribute to the rapid spread and settlement of cacti.

flowers. Flowers of cacti, as a rule, are solitary, in pereskia and rhodocactus they are collected in an inflorescence-brush, almost always sessile, bisexual (with the exception of Mammillaria dioica), usually correct, less often (in Aporocactus, Cleistoeactus, Cochemiea, Schlumbergera) irregular shape.

In most cacti, the flower has a more or less well-developed floral tube. It can be naked (mamillaria, hymnocalycium) or equipped with spines, bristles, hairs. In the flower there is no clear distinction between petals and sepals. The latter gradually pass into the inner brightly colored petals. Stamens numerous. For example, in a giant carnegia, there are up to 3480 of them in one flower! In prickly pear and notocactus Otta ( Notocactus ottonis) they are irritable, i.e., when touched, they move towards the stigma. As a rule, flowers appear one at a time, and in many (ripsalis, myrtillocactus, lophocereus, neoporteria) several flowers form simultaneously in the areole. Most cacti are characterized by the appearance of flowers at the top of the stem and less often in its middle and lower parts (Rebutia, Ailostera, Echinocereus).

Sometimes, under adverse weather conditions, the buds do not develop and turn into a vegetative shoot. Some cacti ( Melocactus) flowers develop on a special organ - cephaly (from cephalus- head). It is a dense felt formation at the top of the stem and appears by the time the plant enters the flowering phase. At this time, the growth point of the stem divides in such a way that instead of ribs, numerous papillae with areoles densely covered with hairs and bristles are formed. The so-called false cephaly (pseudocephaly) is possessed, for example, by pilosocereus Sartorius ( Pilosocereus sartorianus), species of the genus Seticereus. In pseudocephalus, the position of the ribs on the stem does not change, but by the time of flowering, the areoles develop many long hairs and setae. The emerging "head" outwardly resembles a real cephaly. Cactus flowers are pollinated by bees, bumblebees, beetles, flies, ants. And many cacti ( Austrocylindropuntia cylindrica, Gylindropuntia imbricata and etc., Opuntia Imdheimeri, O. elate and etc., Helianthocereus pasacana, Nopalea cochenillifera, Stetsonia coryne, Trichocereus littoralis The flowers are pollinated by birds. Hummingbirds visit the flowers of giant carnegia, pink-flowered neoraymondia, woolly esposta, species of the prickly pear and echinocactus genera. Flowers of pilosocereus Sartorius, cephalocereus, pachycereus are pollinated bats. In representatives of the genus Frailea, flowers do not open under adverse weather conditions (cleistogamous) and self-pollinating. There are cacti that bloom during the day and bloom at night. The latter include the famous "Queen of the Night".

The sizes of flowers are very diverse. The largest flower is considered to be Hylocereus multiroot ( Hylocereus polyrhizus) and selenicereus - 25-30 cm in length, the smallest - flowers of epitheliant and bloomsfeldia. The color of the flowers is white, pink, all shades of red, yellow, lemon green, brownish. The duration of flowering of one flower is from several hours to 10-12 days.

Blooming cacti always bring a lot of joy to lovers of these plants. A huge number of species bloom from April to June. You can choose a collection so that cacti bloom throughout the year. You can speed up the flowering of cacti by 1-3 months.

fruits, seeds. Cactus fruits are berry-like, edible in many species, ranging in size from 2-3 mm to 10 cm. According to F. Buxbaum, they can be classified into juicy, semi-succulent and dry. Thanks to juicy seed stalks, seeds stick to the body of insects, birds, and animals. In notocactus Otta and astrophytum stellate seed stalks contain fats that are readily eaten by ants, which are seed carriers. Cacti with dry fruits have developed other adaptations for dispersing seeds: numerous bristles, hairs, spines, with the help of which the fruits are easily attached to the body of the animal. In addition, dry fruits may fall apart ( Pachycereus pectenaboriginum, Frailea pumila).

An interesting phenomenon (proliferation) occurs in some species of peresian and prickly pear. Its essence lies in the fact that the areoles located on the flower tube form flowers and fruits that serve only for vegetative propagation, like cuttings: falling off, the fruits take root and give new shoots. This phenomenon is most pronounced in proliferating cylindropuntia ( Cylindropuntia prolifera) and sparkling cylindric ( C. fulgida).

Seeds of most cacti with a thin, fragile shell, smooth or rough with tiny tubercles. Prickly pear seeds differ from all other cacti - flat, with a hard roofing shell. In one fruit there can be from 1-3 (Peleciphora) to 1500 (Trixanthocereus) seeds. The smallest seeds are in parodies, blossomfeldia, strombocactus, the largest are in peresian and prickly pear.

Cactus seeds germinate, as a rule, on the 2nd - 10th day. In epiphytic cacti, seeds germinate in the fruit. Cactus seeds remain viable for up to a year or more. According to some reports, the seeds of the cereus and mamillaria germinate after 7-9 years, and for the cracked rosecactus ( R. fissuratus) a case is known when the seeds germinated after 30 years!

Describing the Cactus family, it is necessary to note one more biological feature- extremely slow growth. At home, the height of a 20-30-year-old giant carnegia is no more than a meter, that is, the average annual growth is 2-3 cm. In spherical forms of cacti, slow growth in length is partly offset by growth in thickness. For example, a huge echinocactus at the age of 500 reaches a height of up to 1.5 m in its homeland with a diameter of 1.25 m. The slow growth of cacti persists even in greenhouse conditions. For example, a 70-year-old Gruzon's Echinocactus has a height of 40 cm with a diameter of 20 cm. The average growth per year is 5 mm!

Cacti are associated with a round green hedgehog planted in a small pot, but this is absolutely not the case - they are suitable for indoor cultivation. different types, which botanists divide into 4 groups. This article contains detailed agricultural techniques for growing forest and desert cacti.

Charming thorny plants belong to the Cactus family.

Among indoor plant lovers, there is a fairly large group that collects cacti and other succulents. Why did their choice fall on these plants? The prickly indoor cactus does not take up much space, and caring for this plant is quite simple. During flowering, it is impossible to take your eyes off the plants - bright, showy flowers on a prickly ball can please any grower.

Botanical reference

It's hard to believe that pereskia is also a cactus.

Modern classification involves the division of plants of this species into 4 subgroups:

Pereskiidae (Pereskioideae)

This group includes only one representative (prickly pereskia), which is classified by botanists as a transitional species between deciduous plants and cacti proper. Pereskia has long vine-like stems with sparse spines and large elliptical leaves. An unusual plant blooms with amazing creamy flowers, but they can only be seen on adult plants.

They grow in South and Central America.

Prickly pear (Opuntioideae)

Opuntias are often grown as house cacti. It is easy to distinguish this species from others - the body of the plant consists of flat, thick cakes covered with special small spikes (glochidia). The plant uses small spines to protect against being eaten by animals.

Among the prickly pear there are miniature and giant species, this species from natural habitats has spread throughout the continent, where it can winter without shelter. In Russia, the natural ranges of prickly pear can be found in the Crimea, the Caucasus, and the Lower Volga region. Prickly pear blooms with large flowers, similar to luxurious roses, the fruits of some species are edible.

Mauhienivye (Maihuenioideae)

Includes one genus native to Patagonia. This variety is very similar to prickly pear, but does not have glochidia.

Cactus (Cactoideae)

The largest family includes varieties that grow in deserts and forests. On home windowsills, you can often find original specimens that are part of this group of plants. Outwardly, desert and forest cacti are not at all alike - the first ones have abundant spines, the second ones look like segments, their flat leaves do not have thorny outgrowths at all. The care of these cacti is also very different, due to the different growing conditions of the species in nature, the agricultural technique for caring for home cacti will be discussed below.

Desert

Blooming Mammillaria.

Many types of domestic cacti, which are successfully grown by amateurs on a sunny windowsill, belong to the desert group. These plants have a pronounced dormant period, so it is important to properly care for prickly pets during this time.

Desert cacti are accustomed to sudden changes in day and night temperatures, put up with prolonged drought and scarcity of stony soils, but the harmonious development of these plants is impossible without sunlight. If you decide to start a collection of thorns, you will have to free up a sunny window sill for them.

Types of desert cacti

Composition of desert species.

This subgroup includes most varieties with thorns, including prickly pear. Very often on the windowsills of amateurs you can find a representative of the Mammillaria genus - rounded or oval low cacti grow in colonies. Their spines are small, thin, with tenacious hooks at the ends.

The entire body of mammillaria is covered with papillary outgrowths, flowering of plants occurs at the top, small flowers of pink, white, crimson or yellow color bloom around the circumference. During flowering, mammillaria look like green hedgehogs with wreaths on their heads. After flowering, in place of flowers, fruits are formed in which seeds ripen. Mammillaria grow easily and quickly from seeds, seedlings adapt well to local conditions, forming charming prickly balls.

Prickly pear is protected by small spines that densely cover its body.

Spectacular parodies with large bright colors can often be found in the collections of experienced and novice amateurs. The body of the cactus (round or elongated) is densely covered with long hairs, among which sharp spines are hidden. The original appearance of the plants is given by multi-colored pubescence, as well as surprisingly bright and large flowers.

Spherical rebutia, growing in groups, have many varieties. Large funnel-shaped flowers rise along the body of the cactus from the bottom to the crown. Flowering is long, flower petals are painted in red, pink, crimson tones - very bright.

Ferocactus, azteciums, astrophytums, echinocactus are ranked among the elite of desert cacti. Mature plants are quite expensive, but they can be easily grown from seeds. Elite species have a round (sometimes flattened-rounded) shape, original spines and a ribbed body.

Rare cacti have huge flowers, the diameter may be larger than the parent.

A large group of specific cacti with a columnar shape belongs to the cereus species. Usually cereus grow in colonies, have an elongated shape and resemble a rock. In nature, cereus grow to gigantic sizes (above 40 m).

Very often on the windowsills of amateurs you can find echinopsis - this cactus is not very original in shape, but during flowering it can please with huge flowers of elegant shape. Echinopsis can be round or cylindrical, easily overgrown with numerous children, which can be used for vegetative propagation of the plant.

Agrotechnics care

Desert cacti require bright light, dry wintering at moderate temperatures, and careful watering. You can water the plants only during the growth period, in winter the cacti go to rest, they need to find a bright place at a temperature of + 10 ° C, reduce watering (you can not water at all for 2 months), but with the advent of spring, plant care is resumed by moistening the plants 1 time per month.

It is best to prepare the soil for planting yourself; peat-based store mixes are absolutely not suitable for growing prickly pets.

Each type of cactus requires planting in a specific land mixture, I will give an example of the classic soil composition for prickly natives of desert areas:

• Sod land - 1 hour
• Leafy earth - 1 tsp.
• Clay - 0.5 hours
• Coarse sand - 1 tsp.
• Small pebbles, brick chips or crushed gravel - 0.5 hours.

For planting echinopsis and cereus, peat and humus should be added to the mixture for 0.5 tsp.

It is important to remember that acidic soil is not suitable for planting cacti, the ideal Ph value is not higher than 6.5.

Planting substrate for desert cacti should not be filled with nutrients.

What to do if it is impossible to prepare the substrate yourself? Ready soil can be used by adding coarse sand, crushed stone and clay to it.

At the bottom of the pot when planting plants, it is necessary to lay drainage. Upper drainage is also necessary, it is arranged by adding a layer of dry, sifted sand of a large fraction with laying small pebbles over it.

Forest

These plants are also cacti, but the agricultural technique for caring for them is fundamentally different. Often on the windowsills you can find ripsalidopsis or Schlumbergera. Planted in rocky ground and sun-baked, these forest cacti are a deplorable sight.

Agricultural technology for growing forest species

A plant with wonderful bright flowers.

In nature, forest cacti live on tree trunks, the branches of which serve as a support for long whip-shaped leaves. Plants often live without access to sunlight, so the improper cultivation of these cacti by negligent lovers in the burning sun brings great harm to their appearance - disfiguring dry spots (burns) appear on the glossy surfaces of the leaves.

In the humid climate of tropical forests, these cacti absorb moisture not only with their roots, but with the entire surface of the leaves from the air. When keeping all types of forest cacti in a room, it is very important to provide them with high humidity, for which it is useful to spray the plants with soft settled water, as well as to humidify the air around your pets.

It is impossible to grow plants in the bright sun, so you should shade them in the summer from the scorching sun. The perfect place for growing forest cacti - the east window.

Watering the plants is carried out regularly, preventing the complete drying of the substrate in the pot. In winter, care for forest cacti does not stop - they are also watered with warm water 2 times a month, the ground is carefully loosened to improve aeration of the roots, and the ambient temperature is lowered to +15 ° C. In winter, plants are harmed by dry air, especially during the heating period. Do not forget to humidify the air in the room where forest species grow.

During the budding period, pots with plants cannot be rotated and rearranged - tender buds may fall off, flowering in this case will not occur.

Almost all forest cacti (except epiphyllum) require an annual transplant into a fresh substrate. For planting forest cacti, you can use ready-made soil, soil for violets and begonias is also suitable.

Types of forest cacti

Huge flowers bloom at the ends of the shoots.

A distinctive feature of forest cacti can be considered flat fleshy leaves, they are long or short with smooth edges or curly cutouts. The most interesting leaf shape of Cryptocereus is that its leaf blade is deeply indented on both sides, resembling the skeleton of a fish.

Very often in the collections of flower growers there are Schlumbergera, aporocactus, epiphyllum, ripsalidopsis. All plants are characterized by lush flowering - at the ends of green shoots a lot of buds are formed, which turn into elegant flowers of the original shape and colors.

The petals are like the wings of a hummingbird.

Very often, novice amateurs cannot distinguish a Schlumberger from a ripsalidopsis, but in fact everything is very simple.

Easter cactus.

Ripsadidopsis

The flower has rounded leaf segments without sharp protrusions, blooms in April - May (Easter cactus) with charming flowers of white, orange, red, fuchsia. The shape of the flower is a daisy with thin petals. During flowering, the entire cactus is covered with hundreds of pointed "suns". To stimulate the flowering of the plant, the cactus after flowering is taken out into the fresh air, located away from the sun's rays. The plant is not brought into the room until October. The cooling period helps the plant to set new buds.

Schlumbergera

The leaves consist of flat pointed segments with pronounced outgrowths. Flowers appear in November-December (Rozhdestvennik, Decembrist), they have a complex multi-tiered shape with an elegant limb. There are varieties with orange-yellow, lilac-pink, red and white petals.

Phylocactus (epiphyllum)

Long, flat leaves look like dense belts, flowering occurs in early summer. During flowering, the epiphyllum is completely transformed, its unpresentable appearance is already invisible, because the whole plant is decorated with huge (from 15 to 20 cm) double flowers of elegant shape.

They say that cacti protect the house from thieves and extinguish the negative radiation of computers. To help a person, the cactus itself must be well-groomed and healthy. We hope this article will help you take care of your prickly pets.

The birthplace of cacti is considered to be South America and part of North. Evolutionarily, cacti as representatives of the world of flora appeared approximately 40 million years ago. They belong to the succulent plant family. Thorns appeared not as a decorative element, but with meaning. They have evolved over many centuries and have become a real survival organ.

In the main thick stem of the cactus, a strategic supply of nutrient moisture is concentrated. Another feature of the cactus is the incredibly long roots that go underground and occupy an impressive surface radius in their habitat. Therefore, they can collect life-giving moisture over a fairly large area. Do not think that cacti do not tend to have leaves, like all plants known to us. It's just that the function of the leaves is performed by these very spines - a modified version of the leaves. The spines are based on a material similar to organic matter- chitin.

Cacti abandoned the leaves of the form we are used to for a completely objective reason. As a rule, cacti grow in dry places, and wide leaves would become completely irrational and in large quantities evaporate precious water. In part, the functions of the leaves were taken over by a thick, fleshy trunk. On its surface there are very thin stomata, which, if necessary, open their pores and absorb the carbon dioxide necessary for photosynthesis.

Another unique feature of spines is that they electrostatically attract small water droplets to themselves. Therefore, rain is not always needed for the cactus to get drunk. In the climate where cacti exist, the temperature fluctuates quite a lot. Dew is steadily formed in the air, which is a constant source of moisture for cacti.

In addition to the role of water getters, thorns also perform a defensive function. Few of the animal and plant kingdoms have adapted so successfully to survive in the desert dunes, and many animals would love to eat such a succulent plant. And it is here that thorns come to the defense, with which no animal can cope. Thanks to the spines, cacti are able to be reproductive. The spines secrete nectar that attracts insects, which act as pollinators.

It is curious that the length of the spines depends on climatic conditions. The milder the climate, the rarer the spines. But they are quite long, because. they have only a protective function. The drier the climate, the more thorns on the trunk of the cactus, respectively. The spines contain a large amount of mineral salts and calcium carbonate. So, in order for the spines to grow in the soil, there must be a sufficient amount of calcium. That is why it is necessary to pour old plaster or marble chips into the ground for growing cacti.

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Research project "Cactus - a prickly friend" Completed by: students of 1 "D" class Velikoglo Viktor Logunova Anastasia Primary school teacher: Somova R.V.
Municipal autonomous educational institution "School No. 18 of the city of Lipetsk"

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Hypothesis:
If you create conditions close to natural for cacti, then you can successfully grow these flowers at home. The object of study of this work are cacti.

slide 3

Objective of the project:
Tasks: Learn the history of cactus as a home ornamental plant; Determine the types of cacti in the house; Find out the conditions for growing cacti.
As a result of observations, find out what conditions are necessary for a cactus to bloom.
Problem: indoor cacti do not bloom

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Forms of work
Study of literature; Search for information on the Internet; Watching flowers in the house; Experiment

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cactus history
Cactus is the collective name for plants of the cactus family (lat. Cactaceae). In itself, the word "cactus" comes from the old Greek word of other Greek. κάκτος, which in classical Greek was used to refer to some not well-known plant, apparently quite prickly.

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Cacti in Russia
The appearance of the first cacti in Russia is associated with the name of Peter 1. At the beginning of the 18th century, one of the first botanical gardens, the Pharmaceutical Garden, was organized, now the Botanical Garden in St. Petersburg (Decree of Peter 1 in 1714). Cacti from greenhouses stepped into the world of indoor plants . They were very expensive at that time: a cereus 2 m 50 cm high cost 4 rubles (at that time a worker in the botanical garden received about 2 rubles a month).

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cactus living conditions
The soil is loose, well permeable to water and air, with a high content of sand; abundance of sunlight; uniform summer watering; dry and cold wintering not higher than 10 degrees

Slide 8

Do you know that…
The spines are the armor of the cactus. During a long dry period, the cactus drinks its own water. US scientists dug up a cactus from the ground and hung it from the ceiling. In this state, the cactus lived for 6 years !!! Cactus fruits can be eaten raw, dried, boil compotes, jam, candied or stewed as a side dish for meat.

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Practical activities.
Two cacti were chosen for observation, placed in different conditions, and these plants were cared for in different ways. Studies have been carried out on the growth and flowering conditions of cacti.

Slide 10

Experience No. 1 How the location of a cactus affects its growth and development.
Cactus #1 Cactus #2
Care features: moved, put in different places. Watered: in summer - 2 times a month, in winter - less often Care features: stood on the windowsill on one, permanent place. Watered: in summer - 2 times a month, in winter - less often.
Observation result: Observation result:
less bright coloring, did not increase in growth. bright coloring; increased in growth.

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Experience No. 2 How does the watering regime of a cactus affect its growth and development.
Cactus #1 Cactus #2
Features of care: stood in a permanent place, watered more than once a week. Features of care: He stood in one place, the sun fell on the same side of the flower, watered in the same mode: in summer - 2 times a month, in winter - less often.
observation result observation result
began to rot. bloomed.

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Conclusion.
Indoor plants heal the air in the apartment, and prickly pear cacti, similar to prickly "cakes", even absorb radiation from computer and TV screens. Cacti decorate our house with their flowering. They fill it with unusual shapes and colors, give us the warmth of distant lands, delight us with greenery when all members of our family are winter outside. They love us if we take proper care of them, and give us their beautiful flowers.