Post to the news page to learn about the help settings of MP3 picture and video encyclopedia.
Add to search and return to Baidu Encyclopedia home page to edit the entry cactus directory [hide]
General situation of cactus
History of cactus
Characteristics of cactus
Multiple uses
Indoor cultivation/cultivation
Pest control technology
Mexico's national flower
Water storage function
Alien invasive species
Flower language of cactus
Hong Kong film "Cactus"
The plot of a play
[place name]
History of Cactus: An Overview of Cactus
History of cactus
Characteristics of cactus
Multiple uses
Indoor cultivation/cultivation
Pest control technology
Mexico's national flower
Water storage function
The Flower Language of the Exotic Invasive Species Cactus The Story of the Hong Kong Film Cactus [Place Name] The History of Cactus
[Edit this paragraph] General situation of cactus
Alias fairy palm, overlord tree, flame, fire palm, jade hibiscus and ox tongue (called Quzhou, Zhejiang)
Latin cactus
English name cactus [2]
Scientifically classify angiosperms, dicotyledons, Dianthus, Dianthus, Cactus and Cactus.
Source: Cactus. ) hawthorn, cactus is a cactus plant.
country of origin
Cactus plants are native to tropical and subtropical continents of North and South America and some nearby islands, some of which grow in forests. Most species of succulents are native to South Africa, and only a few are distributed in tropical and subtropical areas of other continents, so South Africa is known as the "treasure house of succulents". From the origin and ecological environment, the above plants can be divided into three categories:
Native to tropical and subtropical arid areas or desert areas. Under the condition of extremely dry soil and air, it survives with the help of water stored in stems and leaves.
Originated in tropical and subtropical alpine arid areas. These areas are short of water, with strong sunshine, strong wind and low temperature. Succulent plants are short, and their leaves are mostly rosette-shaped, or densely covered with wax and fluff, so as to reduce the harm of strong wind and strong light in mountainous areas and reduce excessive transpiration.
Native to the tropical rain forest. These species do not grow in soil, but attach themselves to the rocks of tree trunks and shadow valleys. Its ecological habits are close to epiphytic orchids.
The medicinal method is to use the whole herb as medicine. It can be harvested all year round. Fresh or sliced and dried.
Functions: clearing away heat and toxic materials, removing blood stasis and swelling, invigorating stomach and relieving pain, and relieving cough. Used for gastric and duodenal ulcer, acute dysentery and cough; Externally used for treating parotitis, mastitis, carbuncle and furuncle, snake bite, burn and scald. Price: 3~ 10000 yuan per plant.
Bitter and cold in nature.
Usage and dosage: fresh1~ 2; Take a proper amount of fresh products for external use and apply them to the affected area.
Caution: Stings contain poisonous juice, which may easily cause allergic symptoms such as redness, swelling, pain and itching.
Alias: wind tail, dragon tongue, peaceful grass, fairy palm, Guanyin thorn.
Nature and taste: cold, bitter and astringent.
Meridian tropism: entering the heart, lungs and stomach.
Traceability of medical classics
"Seeking the Grassland": "Eliminate pimples at the beginning and wash hemorrhoids."
Guizhou folk prescription drug collection: "nourishing stomach and spleen, relieving cough and calming the nerves." Treat heart and stomach gas pain and snake edema. "
"Luchuan Materia Medica": "Anti-inflammatory and detoxifying, expelling pus and promoting granulation. The indications are sores, boils and coughs. "
Detailed explanation of materia medica
Traditional Chinese medicine believes that cactus has the functions of promoting qi and blood circulation, clearing away heat and toxic materials, and is mainly used to treat heartburn, swelling and pain, dysentery, hemorrhoids, cough, sore throat, lung abscess, breast abscess, furuncle, fire injury in soup, snake injury and other diseases.
Health care must read.
Edible cactus is one of the vegetables with the highest content of vitamin B2 and soluble fiber.
Edible cactus contains 8 kinds of amino acids and various trace elements necessary for human body, as well as precious components such as Gynura bicolor, Celastrus orbiculatus, hibiscus flower, etc. It not only has many effects on human body, such as clearing away heat and toxic materials, invigorating stomach and spleen, clearing throat and moistening lung, and beauty beauty, but also has obvious therapeutic effects on liver cancer, diabetes, bronchitis and other diseases.
Cactus is high in potassium, low in sodium and low in sugar, and its sugar content is lower than lettuce and cucumber.
cactus
Zygocactus trurncatus cactus
.. plural cacti. Ceres is just a kind of cactus, not a general term for cactus. There are many kinds of cacti, such as Poria cocos, the largest cactus in the world, and Blossfeldia liliputiana, the smallest cactus in the world.
A family of dicotyledonous flowering plants (characterized by having two cotyledons). It belongs to Dianthus. Some authoritative organizations list cactus as an order, and there is only one family-cactus family. Botanists estimate that there are 130 genera and about 1650 species of cactus.
Cactus is native to North and South America, from British Columbia and Alberta to most parts of the south; Its southern border extends to Chile and Argentina. Mexico has the largest variety of cacti. Only Rhipsalis may be native to the Old World and distributed in East Africa, Madagascar and Sri Lanka. However, many scholars believe that this genus was introduced to these areas from other parts of the world.
Cactus is a succulent perennial. Although a few species live in tropical or subtropical areas, most of them live in arid areas. The stem of cactus is usually thick and contains chlorophyll, grass or wood. Most kinds of leaves either disappear or are extremely degraded, thus reducing the surface area of water loss, while photosynthesis is replaced by stems. Only tropical Schizophyllum and Schizophyllum have obvious functional leaves. Roots are usually slender, fibrous, shallow and widely distributed, and are used to absorb surface water.
The size and shape of cactus plants vary greatly, from button-shaped Peott palm (Lophophora), short and rough Rosa roxburghii (Opuntia) and hedgehog palm (Echinocereus) to tall cylindrical barrel palms (Ferocactus and Echinocactus). Most cacti grow in soil, but some tropical species, including Corydalis, Epiphyllum and Schlumberger, are epiphytes. Others grow on hard surfaces, such as rocks. The stems of epiphytes are usually thin and flat. The surface morphology of plants is also different, either smooth or with prominent nodules, ridges or grooves.
The cactus is different from other succulent plants in that its stem has a cushion-shaped structure-community. In almost all kinds of communities, thorns or barbs will grow, from which flowers, branches and leaves (if any) will be born.
The internal structure of the stem of Golden Red Cactus (Opuntia dillenii) is consistent with other dicotyledonous plants, and there is a cambium between the internal xylem and the external phloem. However, stems are mostly composed of thin-walled storage cells, which contain mucilage, which can protect plants from losing water. The stem of cactus is the main organ for producing and storing nutrients.
A few cactus species can produce small plants near the ground level, so as to reproduce asexually. The tissues of various cacti are quite consistent, so the terminal part of one cactus can be grafted to the top of another cactus.
But cacti mainly reproduce through seeds. The flowers of cactus are usually large and gorgeous, and most of them are solitary. All genera have flower tubes (composed of perianth segments, calyx and petals are obviously different or indistinguishable), and the ovary is inferior and one room. There is a style on the ovary, and there are many stigmas at the top of the style to receive pollen. After pollination and fertilization, the ovule develops into seeds (multiple seeds) and the ovary develops into fruit (usually berries). Pollen is carried by wind or birds. Shortly after pollination, the flower tube falls off from the top of the ovary, leaving obvious scars.
Cactus is widely cultivated as an ornamental plant. In addition, Rosa roxburghii (immortal fruit) and Cioglia palm (both cactus) are also edible plants. In South America, cactus, wax cactus and other species are used as living fences, and in some desert areas, wooden columnar cactus is used as fuel. Barrel palm (cactus and cactus) is the water source in an emergency. Lophophora williamsii is a palm with hallucinatory effect, which has been used in some ceremonies since Columbus arrived in America.
Cactus is a big family with at least two thousand members. Its hometown is in America and Africa, especially Mexico, and it is called "cactus kingdom", and cactus is praised as "Xiantao" by Mexicans. China Yunnan minority areas also have the habit of taking cactus fruit as fruit. There is a beautiful legend in the local area: a huge Shan Ying flies around looking for a place to live with a snake in its mouth. When it landed on a cactus full of yellow flowers, it never wanted to leave. Since then, Mexicans have established their home in this vibrant place-Mexico City. The design of the Mexican national emblem is based on this legend.
[Edit this paragraph] The history of cactus
Cactus flowers are native to South America and North America, and can be found in Ontario, Canada at 50 degrees north latitude and Santa Cruz, Argentina at 50 degrees south latitude.
According to relevant records, after Columbus discovered the New World in 1496, cactus was first brought to Europe by sailors from Caribbean islands in South America in 1540, and was introduced to Japan in 1669. 1840, the botanical dictionary published in Britain recorded 400 species of cactus cultivation. At that time, cactus flowers had developed from wild introduction to artificial cultivation, and the original wild cactus had been improved into special ornamental flowers through horticultural cultivation.
[Edit this paragraph] Characteristics of cactus
Cactus mostly grow in arid environment. Some are cylindrical, 10 meters high and weigh about 20000 kilograms. They stand tall and spectacular. Some prickly cacti, some of which live for more than 500 years, can grow into giant balls with a diameter of two or three meters. People cut the upper part of it and dig soft and juicy stem meat to quench their thirst. Cactus also has a special ability. In the dry season, it can go into a dormant state without eating or drinking, minimizing the consumption of nutrients and water in the body. When the rainy season comes, they wake up very sensitively, and their roots immediately become active, absorbing a lot of water, making plants grow rapidly and blossom and bear fruit quickly. The roots of some cactus plants will turn into carrots, which can store 70 or 80 kilograms of water. Someone once put a cactus in a dry paper bag for more than two years. Although some of them withered, one cactus was put into a flowerpot. After watering, it quickly grew new roots and resumed its growth. Cactus is appreciated by human beings for its wonderful structure, amazing drought tolerance and tenacious vitality.
Cactus also has grotesque stems and bright flowers. Although the grotesque cactus with sharp spikes is daunting, the flowers they produce are particularly delicate and colorful, like tassels. The whip-like "Moonlight Queen" has large white flowers with a diameter of 50 to 60 cm. Epiphyllum, known as "a flash in the pan", is an epiphytic cactus plant native to tropical forests in Central and South America.
Cactus wins with flowers only for one reason, and thorns and fluff of different shapes and colors are also loved by many viewers. In particular, some bright red and golden thorns and white fluff varieties are even more varied. No wonder some people call it a "living handicraft".
Physiological characteristics of cactus photosynthesis: Sedum plants "Sedum acid metabolism" (CAM-) belong to C4 plants. The representative plants are cactus, pineapple and longevity flower.
In order to survive in arid tropical areas, CAM- plants has developed a set of survival strategies, and CO2 fixation will be separated in time in calvin cycle. In this way, excessive water loss can be avoided, because the stomata are only open at night to absorb CO2.
Pure C4 plants fix carbon dioxide through spatial separation (mesophyll cells and vascular bundle sheath cells). Sedum acid metabolizing plants follow the following circadian rhythm:
At night: CO2 is absorbed and fixed on phosphoenolpyruvate (PEP). The generated oxaloacetic acid (OA) will be reduced to malic acid and stored in vacuoles of cells. This process is accompanied by acidification, and the reducing substances produced by the decrease of pH value in daytime photoreaction will also play a role here.
During the day: acid substances in vacuoles (mainly malic acid and also aspartic acid) will be decarboxylated. The released CO2 enters calvin cycle.
CAM plants must prepare enough phosphoenolpyruvate for fixing CO2 at night. Because of this, plants store starch during the day and convert it into phosphoenolpyruvate at night.
This is probably the case with CAM access. In fact, it divides photosynthesis into two main steps. One is carried out during the day, which is the so-called photoreaction stage. At this stage, energy is obtained by absorbing light, water is electrolyzed, oxygen is released, and reducing force is generated. Then the second half step of photosynthesis-CO2 fixation is carried out at night.
[Edit this paragraph] Multiple purposes
People often think that cactus is just an ornamental plant and has no use. In fact, the fruits of many cactus plants can not only be eaten raw, but also made into wine or dried. Cactus has always been a traditional food in the United States, and it is an indispensable characteristic vegetable and fruit in people's daily life. People wash and chop the cactus and cook it in soup, or bake it on the stove, or make it into cake stuffing, or pickle the fresh cactus directly, and some make wine with cactus. In the Mexican market, the tender stems of some flaky cactus can be sold as vegetables. The trunks of some columnar cacti have been used as building materials by Indians. The flaky stems of cactus can not only be used as feed for livestock, but also its viscous juice can be used as a purifying agent to purify water. In some places, some prickly cacti are planted next to the house as barbed fences.
Medicinal use of cactus
Every 100g edible cactus contains about 220g of vitamin A, 0/6mg of vitamin C/kloc-0, 6 g of protein/kloc-0, and 2.7mg of iron, which can generate 25kcal-30kcal of heat. In recent years, many countries began to treat arteriosclerosis, diabetes and obesity with cactus, and achieved good results. It is said that this is mainly because the vitamins contained in cactus can inhibit the absorption of fat and cholesterol and slow down the intake of glucose. Edible cactus is rich in nutrition, contains a lot of vitamins and minerals, and has the functions of lowering blood sugar, blood lipid and blood pressure. The tender stems of edible cactus can be eaten as vegetables, and the fruit is sweet. Old stems can also be processed into health care products and medicines with the functions of reducing blood fat and cholesterol. Cakes, snacks and dishes in Mexico are famous. They are cooked with the flowers of local cactus plants.
As a medicinal plant, cactus was first seen in Zhao Xuemin's Compendium of Materia Medica in Qing Dynasty. According to the book, cactus is light in taste and cold in nature. It has the functions of promoting qi and blood circulation, clearing away heat and toxic materials, relieving swelling and pain, invigorating spleen and stopping diarrhea, calming the nerves and inducing diuresis, and can be used to treat various internal and external diseases. According to the herbal prescription written by Liu Shan in the Qing Dynasty, cactus tastes bitter and cold, and it is not difficult to cure diarrhea caused by five hemorrhoids. Children with baldness are covered with sesame oil, and insect sores and scabies are washed safely. "Seeking the Grassland" contains: cold, eliminating novelty and washing hemorrhoids. Lu Chuan's materia medica records the functions of diminishing inflammation, detoxicating, expelling pus and promoting granulation, and is used to treat sore, carbuncle, swelling and cough. "Lingnan Materia Medica Collection" records: "Cactus is baked to cure breast carbuncle and initial tuberculosis. "Minnan Folk Herbs" says that applying a proper amount of fresh cactus whole grass to the affected area can completely cure palmar furuncle. " "Guangxi Chinese Herbal Medicine" contains: cactus stops diarrhea and treats enteritis and diarrhea. "Mindong Materia Medica" contains: it can eliminate phlegm, relieve intestinal toxicity, strengthen stomach, relieve pain, nourish, relax tendons and activate collaterals, heal sores and stop bleeding. Treat intestinal wind, hemorrhoid, hemorrhage, lung abscess, gastropathy, and traumatic injury. Hunan Pharmacology records that cactus can relieve swelling and pain, promote qi and blood circulation, eliminate dampness and reduce fever, and promote granulation. The Picture Book of Chinese Medicinal Plants records that if the cactus skin is mashed, it can be used to treat fire injury and acute mastitis. Decocting with water can cure dysentery. "Classification of Materia Medica" contains: specializing in treating swelling pain, detumescence toxin and malignant sores. "Guizhou folk prescription drug collection" contains: cactus is a stomach-strengthening and stomach-nourishing agent, which can also replenish spleen, relieve cough and soothe the nerves. Treat heart and stomach gas pain, snake wound edema. It can be seen from the data records that cactus has a remarkable effect on treating furuncle and swelling. The existing reports are used for adjuvant treatment of nephritis, diabetes, palpitation insomnia, arteriosclerosis, hypertension, heart disease, obesity and liver disease, as well as dysentery, asthma, stomachache and intestinal hemorrhoid bleeding.
[Edit this paragraph] Indoor cultivation
Cactus has been transplanted from wild to indoor cultivation, which reflects a trend of urban residents to choose potted flower varieties. Because of the limited building area and dry air, it is often difficult to cultivate large or exquisite potted flowers. Only some varieties with small size, drought tolerance, simple management and high ornamental value are most suitable, and cactus plants just meet these requirements.
Indoor potted cactus, it is advisable to choose varieties with small spheres and many flowers. In cultivation, this plant should not be considered drought-tolerant, and its normal watering and fertilization should be ignored. Indoor cultivation can create a closed space with high temperature and high humidity with lead wire and plastic film on the windowsill. Under this condition, most cacti not only grow fast, but also have crystal clear colors.
Potted soil requires calcareous sandy soil or sandy loam with good drainage and ventilation. Don't water the newly planted cactus first, just spray it several times a day, then water it a little after half a month, and then water it normally after a month when the new roots grow. When the temperature is low in winter, plants should be watered less when they enter dormancy. After spring, with the increase of temperature, the dormancy of plants is gradually released, and watering can be gradually increased. Apply decomposed dilute liquid fertilizer every 10 day to half a month, and do not apply fertilizer in winter.
Under the general residential conditions, it is not difficult to make full use of space, plant dozens of pots of various cacti and arrange a small "cactus garden". At the turn of spring and summer, all kinds of cacti on the windowsill produce dazzling flowers. After work, people can rest under such conditions, which can not only eliminate fatigue, but also enjoy the natural beauty.
[Edit this paragraph] Pest control technology
First, pest control:
(1) Pieris rapae and locust: spray 25% deltamethrin 2000 times;
(2) Prevention and control of red spider: defense is the main factor, and the breeding environment should be properly ventilated, but a certain humidity should be maintained to avoid sultry and dry. Commonly used drugs are 40% omethoate 1000- 1500 times solution and 40% dicofol 1000 times solution. Spraying 1 time every 7- 10 days in high temperature and dry season, and spraying thoroughly before overwintering.
(3) Control of scale insects: Because there are waxy scales on the adults of scale insects, drug control often fails to achieve the expected results, so more attention should be paid to prevention. Farms should be kept clean. When scale insects are found, bamboo pieces can be scraped off in time, or branches with many insects can be cut off and burned. Drug control of scale insects must be carried out shortly after eggs hatch and before wax shells grow, and it must be sprayed repeatedly to be effective. The drugs used are usually 1000 times of 50% malathion, 800 times of 25% ethion EC, 40% omethoate EC and 80% dichlorvos EC with 1000 times of water.
(4) grubs, needle worms and cutworms: 50% phoxim 800- 1000 times solution can be used for irrigation.
Second, the disease control:
(1) Prevention of rot: Prevention should be the main measure to prevent rot. First of all, improve the environmental conditions of breeding places, which can greatly reduce the occurrence and spread of pathogenic bacteria. Secondly, it is necessary to strengthen cultivation management. Do not mix immature organic fertilizer into the planted soil, and the fertilizer should be light and not thick. If you find waterlogging, you should drain it in time. You can cut off some rotten roots and plant them when the wound is dry. Spraying fungicides on cactus or the surrounding environment regularly has a certain effect on preventing rot. Commonly used fungicides are zineb, carbendazim and Tobuzin.
(2) Gold spot, pockmarked spot and scab: 75% chlorothalonil 800 times solution or 50% carbendazim 600-800 times solution or 70% thiophanate methyl can be sprayed;
(3) Rust: 25% triadimefon can be sprayed 2000-3000 times.
[Edit this paragraph] The national flower of Mexico
Mexico is known as the "cactus country". Cactus is the national flower of Mexico. According to legend, cactus was given to Mexicans by God. Cactus has the reputation of "desert hero flower". There are more than 2000 kinds of cacti in the world, about half of which are from Mexico. In the harsh environment, no matter how barren the soil is and how dry the weather is, the cactus on the plateau is always full of vitality and straight up, which constitutes a unique feature of Mexico. Don't try to infringe it. It is full of thorns, tenacious vitality and tenacious personality. It doesn't care about water, waterless, hot or cold weather, but it can bloom bright and beautiful flowers on emerald palm stems, which is a symbol of the Mexican people's strength, courage, unyielding and fearless. In order to show the elegant demeanor of cactus and carry forward the spirit of cactus, a cactus festival is held in Mipa Alta near the Mexican capital every year in mid-August. During the festival, lanterns and colorful decorations are hung on the government seat, and restaurants are set up around it to display and sell all kinds of cactus food.
[Edit this paragraph] Water storage function
There is a layer of wax on the surface of cactus, and the leaves have evolved into needles, which reduces the evaporation of water.
Cactus evolved fleshy tissues, waxy skin, sharp thorns and specialized roots, which gave them all the growth advantages in this difficult ecological environment. The trunk is like a reservoir, which can expand and contract according to the amount of water it stores. The wax protective layer on the skin can keep moisture and reduce water loss. Sharp thorns can prevent thirsty animals from treating it as a free drink.
They usually develop many shallow roots, only a little below the surface, and the distribution of roots can extend to several feet around to absorb as much water as possible. When it rains, cactus will grow more roots. When it is dry, its roots will wither and fall off to keep water supply. Edwards said: "cactus is more closely combined with water than the soil in which it grows." When growing, cactus faces the risk of losing soil moisture, so it has to be separated from the soil. "
[Edit this paragraph] Alien invasive species
At the end of Ming Dynasty, cactus was introduced to China, and now it can be seen all over the country. In the coastal areas of South China and the southwest dry-hot valley, cactus has defeated the local native plants and become the dominant community, where the original natural vegetation landscape may never be seen again.
In Australia, the invasion of cactus is more harmful, and the local government and people have taken various measures to fight cactus, with little effect. Later, the problem was solved by introducing natural enemy Gaby crassus caterpillar from South America.
[Edit this paragraph] The flower language of cactus
Cactus has a soft heart. At the beginning of creation, cactus was the most delicate thing in the world. She is as delicate as water, and she may die at the slightest touch. God couldn't bear to put a suit of armor on her heart, as hard as iron and with hurtful steel thorns. Since then, no one can see the heart of the cactus, and all the creatures near her will bleed profusely. After a long time, a brave man tried to eradicate this evil thing. The sword fell and the cactus became two halves, but the middle was green liquid. It turned out to be a sealed cactus heart. Because no one understands loneliness, it becomes a teardrop, and the green teardrop makes the weak cactus more prominent in her strength. So the flower language of cactus is-strong.
Appearance characteristics of cactus
Primitive cactus plants have leaves. They were originally distributed in less arid areas, and their appearance is not much different from that of ordinary plants. Just because of the vicissitudes of life, the originally humid areas have become more and more dry. In order to adapt to the environment and survive, the shape has changed. Normal flat leaves gradually degenerate into cylinders, then become scales, and finally disappear completely. Today, some primitive cacti are distributed in some less arid areas of Central America. Among them, the species of cactus, lone vegetable and lone vegetable have normal flat leaves, but their size and meat quality have changed. Cactus leaves are big and thin, and there is basically no meat. In the south of China, the most common species of this genus-leaf cactus (also known as tiger thorn and wood unicorn) can often be seen crawling on the wall, but if it doesn't bloom, it is often mistaken for a common flowering shrub-bougainvillea. The leaves of Opuntia grandiflora of this genus are as long as 15 cm. Cactus, red sandalwood, red sandalwood and cactus also have leaves, but they all degenerate into cylindrical shapes, and most of them only grow in the tender part of the stem and fall off quickly. Of course, according to different species and different habitat conditions, the size, shape and life span of these single leaves are very different. The conical leaves of Mai Huna are only 0.4-0.7 cm long, while the cylindrical leaves of drill cactus are 12 cm long, and each leaf can exist for 3-4 years, so it always exists in the upper part of its stem.
Except the cactus with leaves mentioned above, other cactus plants have no leaves, but evidence that leaves once existed can still be found. Some experts pointed out that the prickles of cactus are actually developed from axillary buds. Some experts also pointed out that many kinds of cactus, the protrusion below the base of its thorn is equivalent to the leaf base of normal leaves.
Step 2 stop
The stem characteristics of primitive cactus with normal flat leaves are also different from those of most species. Some are liana shrubs, and the epidermis of the stems is usually not green, except for the tender parts, most of them are lignified. Some kinds of stems, such as common trees, are very tall and highly lignified, such as Bahia cactus and Moon Desert. Their main stems are 8-9 meters high.
The stems of species with cylindrical leaves are usually unsegmented. For example, the general's stem is 2 meters high, and only one section is upward, while many species of the same genus have flat jointed stems. Although the pig's ear palm (opuntia brasilnsis) has a flat jointed stem, its lignified main stem is very high, and the flat jointed stem is just a twig. However, the woody stems of cactus species with inconspicuous cylindrical leaves does not exist or is inconspicuous. Those species without leaves, because of their photosynthetic function, are mainly borne by stems, so under normal circumstances, the stems are green and will not be lignified. Morphologically, it can be said that no family of plants is as varied as cactus: some are flat as mirrors, some are lampstands and organs, some are overlapping mountains, and some are slender as snakes. Most of them are spherical or nearly spherical, which is the result of long-term adaptation to arid environment. Because of the same volume, the spherical surface area is the smallest and the transpiration is also reduced. So in the whole cactus family, spherical species account for more than half. 199 1 year, the United States published a picture book of cactus, which collected all spherical species, excluding cultivated varieties, hybrid collection and ban Jin types, reaching 1098 species, but as far as the author knows, not all of them were included. People usually call cactus lovers "fairy fans" or "keeping balls for fun", and we can also see the weight of spherical species in cactus.
3. Ribs and verrucous processes
Except for primitive species, cactus stems are horned. The species of Cactus, Hedysarum and some Phragmites have only two edges, while the species of Ranunculus and Ranunculus usually have three edges, and all other genera and species have more than four edges. Among them, the number of sides of spherical species is more, and some species have as many as 120 sides, generally more than 10 sides. This is of great significance to adapt to the arid environment. The origin of many cactus plants has such characteristics: it doesn't rain for a long time every year and it rains heavily for a short time in rainy season. The cactus growing in this environment is shrinking in size due to the continuous loss of water in dry season. Once it rains, it absorbs water to the maximum extent and makes the plant expand rapidly. If the ribs don't stretch like accordion folds, the skin will definitely break. The number and arrangement of edges objectively provide a basis for us to distinguish types, which has certain significance in classification.
In addition to the edge, cactus stems also have verrucous processes. This is a unique structure. In fact, in many spherical species, even without obvious verrucous processes, there are transverse tumor-like segments on the longitudinal edge, such as Aralia, gymnosperms, Echinococcus, Leptospira and so on. Verrucous process is the result of further development of these plants adapting to arid environment. With verrucous protrusions, it is more convenient for plants to stretch and dissipate heat. The small bulb of mastoid is attached to the axil of wart, and the tender bulb can be protected by wart and the thorn at the tip of wart to avoid sun exposure and animal damage. Therefore, at present, all taxonomists believe that the genus with obvious wart process is the most evolved species in cactus family.
According to different species, the shape, length, diameter and texture of verrucous processes are quite different. The pyramid-shaped wart in Huangshan is 12 cm long, while the villain hat in the moon world is only 0.2 cm long. Wu Yuyu, Venus and Neptune have soft wart processes, while Poirot's pontine process is hard. The species of Quercus are arranged in a rosette shape, and the sunlight can be fully seen in each process. The fertile soil of Huangshan Mountain is clustered at the end of the stem like agave. However, the wart processes such as the hope ball and the broken piano ball of the mastoid genus are strictly arranged in a logarithmic spiral shape around the growing point, and the pattern is perfect from above. The shape, size and arrangement of this wart are a basis for people's classification.
4. Spine seat, thorn and hair
Spine seat is a unique organ of cactus plants. Essentially, the thorn base is a short branch with abnormal height, which looks like a cushion structure on the surface. There are many kinds of buds on the thorn base, including leaf buds, flower buds and adventitious buds, so not only thorns and hairs grow on the thorn base, but also flowers, bulbs and branches grow on the thorn base. The size and arrangement of thorn seats are different. The spinous process of Saturn's crown, a columnar species, is as big as 20 cm, while the spinous process of the moon world and small truffle jade is only 0.2 cm. Most kinds of thorns are round or oval, with a certain distance between them, while the thorns of Baiyun Pavilion and Uber Ball are long and connected end to end on the edge.
Sutures are generally distributed on the stem. However, some species also have thorns in roots, flower receptacles, ovaries and fruits.