All cultivated plants on which humanity today feeds have descended from wild plant species that ancient man used for food. Then people noticed that these plants are much more profitable to grow themselves. Then agriculture was born. The moment of the emergence of agriculture is a radical turning point in the history of human society. The cultivation of the land allowed man to multiply the amount of food, because now he not only hunted and collected what he could find in nature, but began to produce food himself. This moment is also called the Neolithic Revolution. It first began in the Middle East, about 10,000 years ago, and came to America the latest. However, many peoples of the Earth, such as the American Indians, Pygmies or Aborigines, have not switched to agriculture to this day, preferring to remain hunters and gatherers in the same way as their ancestors did tens of thousands of years ago.
Modern plants and their fruits that we eat are not at all the same as they were thousands of years ago, when they were first discovered by man. Harvest after harvest, he selected the most perfect plants, as he noticed that their properties are transferred to plants grown from selected seeds. So, at first unconsciously, and then deliberately for thousands of years, artificial selection and selection was carried out - the breeding of new varieties of plants. In recent decades, people have learned to change plants at the genetic level without selection, but through modern technologies genetic engineering. Plants with altered genes are called genetically modified. They have significantly better performance in terms of productivity and adaptability to adverse environmental factors than their predecessors, bred by conventional selection. However, how safe genetically modified plants are when eaten remains to be seen.

Of course different plants happened in different regions planets. Scientists began to study the geography of their origin after the discovery by Charles Darwin of the laws of evolution and selection. Darwin put forward the idea that all species had centers of origin where they first arose. In 1883, A. Decandol published a work in which he established the geographical areas of the initial origin of the main cultivated plants. However, the most complete and holistic theory of the centers of origin of cultivated plant species was formulated by Nikolai Ivanovich Vavilov (pictured) in the course of research in the 20-30s of the last century. To do this, he had to travel around almost all the Earth - in America, and. During his expeditions, Vavilov collected the richest collection of cultivated plants, found family ties between them, predicted the previously unknown, but genetically incorporated, properties of these cultures, possible for breeding. Unfortunately, the science of genetics, without which it would be impossible to make all these discoveries, or develop productivity Agriculture, in the Soviet Union was recognized as false and ideologically hostile. Since she argued that the properties of living beings, including humans, are determined by heredity, which contradicted the ideas of universal equality promoted by the communist regime. N.I. Vavilov, like many other Soviet scientists of those times, was repressed in 1940 and died in prison in 1943.

During the study, N.I. Vavilov, 7 main geographical centers of origin of cultivated plants were identified.

South Asian tropical center (about 33% of total number cultivated plant species). (cucumber, lemon, jute, mango, rice, banana, coconut tree, black pepper)
East Asian center (20% of cultivated plants). (millet, soy, radish, Walnut, mandarin, persimmon, bamboo, ginseng)
Southwest Asian center (4% of cultivated plants). (wheat, barley, rye, plum, hazelnut, date palm)
Mediterranean center (approximately 11% of cultivated plant species). (oats, flax, laurel, grapes, cabbage, zucchini, parsley, celery, peas, beans, carrots, beets, radishes, mint, cumin, horseradish, dill)
Ethiopian center (about 4% of cultivated plants). (coffee, sorghum, cotton, sesame, watermelon)
Central American center (about 10%). (corn, beans, pumpkin, cocoa, pepper, sunflower, tobacco, Jerusalem artichoke, papaya)
Andean (South American) center (about 8%) (potato, tomato, pineapple, hevea, peanuts)

N. I. Vavilov deduced seven main centers of origin of cultivated plants. Many species of cultivated plants turned out to have two or three centers of origin.

Almost all seven centers of origin of cultivated plants are confined to mountainous tropical and subtropical regions in the band between 20° and 45° N. sh.

V.P. Alekseev established that the geographical centers of the formation of human races were associated with the Asian centers of the appearance of cultivated plants and even the ethnic picture of the world until the 17th century: Caucasoids - the Mediterranean center, Mongoloids - East Asian, Americanoids - the centers of the New World. For centuries, peoples have been chained to their food niche.

Given the complexity of the selection process, the centers of modern varietal richness of cultivated plants can serve as indicators of the origins of agricultural crops, and hence civilizations.

The oldest hearth Southwest Asian(according to the followers of N. Vavilov, it can also be divided into two centers - Western Asia and Central Asia) from which 14% of all cultivated plants came out.

Asiatic center

AT Western Asia in the territories of modern Palestine, Iran, Iraq, Turkey, Jordan cultivated wheat (one and two-grain), peas, fruit crops. The goat and the ancestors of the sheep, the Asian mouflon, were also domesticated here.

Central Asian center

AT Central Asian In the center, which includes the spurs of the Western Himalayas (Punjab, Kashmir, Hindu Kush), the maximum concentration of a variety of cereals (soft wheat with 42 chromosomes), legumes, flax, and carrots was noted. On relatively small space for only a few hundred kilometers, the population cultivates a colossal variety of soft wheats. Some of them are found nowhere else on Earth.

Later, under the influence of the Southwest Asian focus, a mediterranean center(11% of all cultivated plants), from which many vegetable crops originate, including beets, turnips, cabbage.

Ethiopian highlands or Abyssinia (4% of all cultivated plants) was the birthplace of the coffee tree and barley. The amount of durum wheat and barley cultivated on it exceeds all their diversity in all other countries. the globe. A number of cultures are also found nowhere else. Among them are teff cereal, purple-grained wheat, oilseed chickpeas. Flax was cultivated not for the sake of oil and fiber, but as a bread plant - for flour.

Another major center South Asian(33% of all cultivated plants), where rice was cultivated, cucumber and some citrus fruits originated from here. material from the site

From mountainous areas South China(East Asian center - 20% of all cultivated plants) buckwheat, soybeans, radishes, walnuts, and many citrus fruits have spread.

AT Mesoamerica- The Central American focus (10% of all cultivated plants) traces of the transition to a productive economy are attributed to the end of 3 thousand BC. - and associated with maize (corn) and legumes.

Practical work №3

cultivated plants. Centers of origin of cultivated plants

Theoretical part

Main centers of origin of cultivated plants

(according to N. I. Vavilov)

Sino-Japanese. World crop production owes East Asia the origin of many cultivated species. Among them are rice, multi-row and naked barley, millet, chumiza, naked oats, beans, soybeans, radish, many types of apple trees, pears and onions, apricots, very valuable types of plums, oriental persimmon, possibly orange, Mulberry tree, sugarcane Chinese, tea tree, short staple cotton.

Indonesian-Indochinese. This is the center of many cultivated plants - some varieties of rice, bananas, breadfruit, coconut and sugar palms, sugar cane, yams, manila hemp, the largest and tallest species of bamboo, etc.

Australian. Australia's flora has given the world the fastest growing woody plants - eucalyptus and acacia. Also found here are 9 wild species cotton, 21 types of wild tobacco and several types of rice. In general, the flora of this continent is poor in wild edible plants, especially with juicy fruits. At present, crop production in Australia is almost entirely based on foreign-origin cultivated plants.

Hindustani. The Hindustan Peninsula was of great importance in the development of crop production in ancient Egypt, Sumer and Assyria. This is the birthplace of spherical wheat, the Indian subspecies of rice, some varieties of beans, eggplant, cucumber, jute, sugar cane, Indian hemp, etc. In the mountain forests of the Himalayas, wild species of apple, tea tree and banana are common. The Indo-Gangetic Plain is a huge plantation of cultivated plants of world importance - rice, sugar cane, jute, peanut, tobacco, tea, coffee, banana, pineapple, coconut tree, oil flax, etc. The Deccan Plateau is known for the cultivation of orange and lemon.

Central Asian. On the territory of the center - from the Persian Gulf, the Hindustan peninsula and the Himalayas in the south to the Caspian and Aral Seas, o.ch. Balkhash in the north, including the Turan lowland, are of particular importance fruit trees. Since ancient times, apricot, walnut, pistachio, sucker, almond, pomegranate, fig, peach, grapes, wild types of apple trees have been cultivated here. Some varieties of wheat, bulb onions, primary types of carrots and small-seeded forms of legumes (peas, lentils, fava beans). The ancient inhabitants of Sogdiana (modern Tajikistan) developed high-sugar varieties of apricots and grapes. The wild apricot still grows in abundance in the mountains of Central Asia. Varieties of melons bred in Central Asia are the best in the world, especially the Chardjou melons, which remain suspended throughout the year.

The origin of cultivated plants according to Zhukovsky

Anterior Asian. The center includes Transcaucasia, Asia Minor (except for the coast), the historical region of Western Asia, Palestine and the Arabian Peninsula. Wheat, two-row barley, oats, the primary crop of peas, cultivated forms of flax and leeks, some types of alfalfa and melons originate from here. This is the primary center date palm s, the birthplace of quince, cherry plums, plums, cherries and dogwoods. Nowhere in the world is there such an abundance of wild wheat species. In Transcaucasia, the process of the origin of cultivated rye from field weeds, which still clog wheat crops, has been completed. As wheat moves north, winter rye, as more winter-hardy and unpretentious plant became pure culture.

Mediterranean. This center includes the territory of Spain, Italy, Yugoslavia, Greece and the entire northern coast of Africa. Western and Eastern Mediterranean - homeland wild grapes and primary center of its culture. Wheat, legumes, flax, and oats evolved here (in the wild in Spain, on sandy soils, Avena strigosa oats with strong immunity to fungal diseases have been preserved). In the Mediterranean, the cultivation of lupine, flax, and clover began. A typical element of the flora was the olive tree, which became a culture in ancient Palestine and Egypt.

African. It is characterized by diversity natural conditions from moist evergreen forests to savannas and deserts. In crop production, at first only local species were used, and then those already introduced from America and Asia. Africa is the birthplace of all types of watermelon, the center for the cultivation of rice and millet, yams, some types of coffee, oil and date palms, cotton and other cultivated plants. The origin of the kulebasy gourd, cultivated everywhere in Africa, but unknown in the wild, raises a question. A special role in the evolution of wheat, barley and other cereal plants belongs to Ethiopia, on the territory of which their wild ancestors did not exist. All of them were borrowed by farmers already cultivated from other centers.

European-Siberian. It covers the territory of all of Europe, except for the Iberian Peninsula, the British Isles and the tundra zone, in Asia it reaches the lake. Baikal. It is associated with the emergence of sugar beet crops, red and white clovers, northern alfalfa, yellow and blue. The main significance of the center lies in the fact that European and Siberian apple trees, pear, cherry, forest grapes, blackberries, strawberries, currants and gooseberries were cultivated here, wild relatives of which are still common in local forests.

Central American. He occupies the territory North America, bounded by the northern borders of Mexico, California and the Isthmus of Panama. In ancient Mexico, intensive crop production developed with the main food crop being corn and some types of beans. Pumpkin, sweet potato, cocoa, pepper, sunflower, Jerusalem artichoke, shag and agave were also cultivated here. Nowadays, wild types of potatoes are found in the center.

South American. Its main area is concentrated in mountain system Andes with rich volcanic soils. Andes - the birthplace of ancient Indian types of potatoes and various kinds tomatoes, peanut crops, melon tree, cinchona, pineapple, hevea rubber, Chilean strawberries, etc. Potato (Solarium tuberosum) was cultivated in ancient Araucania, which probably comes from the island of Chiloe. Neither Peruvian nor Chilean potatoes are known in the wild and their origin is unknown. In South America, a culture of long-staple cotton arose. There are many wild types of tobacco here.

North American. Its territory coincides with the territory of the United States. It is of particular interest primarily as the center of a large number of wild grape species, many of which are resistant to phylloxera and fungal diseases. The center is home to over 50 wild herbaceous species sunflower and the same number of lupine species, about 15 plum species, large-fruited cranberries and tall blueberries were cultivated, the first plantations of which have recently appeared in Belarus.

The problem of the origin of cultivated plants is quite complicated, since sometimes it is impossible to establish their homeland and wild ancestors. Often a cultivated plant occupies large areas and is of great importance in crop production not in the center of cultivation, but far beyond its borders. In this case, one speaks of secondary centers of cultivated plants. For rye from the Caucasus and Chilean potatoes, this is the temperate zone of Eurasia. Peanuts from Northern Argentina are now bred in Tropical Africa. Manchurian soybean in the USA covers an area of ​​about 20 million hectares. Peruvian long-staple cotton has taken a leading place in crop production in Egypt.

As noted by A. I. Kuptsov (1975), cultivated plants are a young group of species that have significantly pressed wild flora on Earth. Among them are the three "main breads of mankind" (rice, wheat and corn) and minor cereal plants (barley, oats, rye, millet, sorghum). Large areas are occupied by starch-bearing plants (potatoes in countries with a temperate climate, sweet potatoes, yams, taro, and others in more southern regions).

Leguminous crops (beans, peas, lentils, etc.) and sugar-bearing crops (sugar beet and sugar cane) are widespread. Fibrous plants (cotton, flax, hemp, jute, kenaf, etc.) provide a person with clothing and technical fabrics. The modern human diet is unthinkable without dishes prepared from fruit, berry aromatic and tonic plants, which are also widespread. The role of plants-sources of rubber in everyday life and industry is great, medicines, tannins, cork, etc. Modern animal husbandry is based on the cultivation of fodder plants.

Cultivated plants develop under the control of man, whose breeding work leads to the emergence of new varieties.

N. I. Vavilov’s research on the centers of origin of cultivated plants had great importance to establish the places of domestication of the first animals. According to S. N. Bogolyubsky (1959), the domestication of domestic animals probably took place in different ways: the natural rapprochement of man with animals, the forced domestication of young, and then adults.

The time and place of domestication of the first animals are judged mainly by the excavations of the settlements of primitive man. In the Mesolithic era, a dog was domesticated, in the Neolithic era - a pig, a sheep, a goat and a large cattle, later - a horse. The hypothetical centers of origin of domestic animals are determined by the ranges of their likely wild relatives. However, the question of the wild ancestors of domestic animals is not completely clear. It is assumed that the wild ancestors of cattle were tours, sheep - wild sheep common on the islands of Corsica and Sardinia, in Western, Central and Central Asia, goats - markhorn and bezoar goats, horses - the Przewalski horse and tarpan, domestic camel (Bactrian) - wild camel (haptagai), llamas and alpacas - guanaco, domestic goose - gray goose, etc.

It is easy to establish the places of origin and domestication of those animals whose ancestral ranges were small, for example, the yak. For animals such as dogs, pigs and cattle, whose wild ancestors were widely distributed in Eurasia and Africa, it is difficult to establish the alleged centers of origin. Probably, the first centers of origin of domestic animals were the Near and Near East, and then the areas of ancient cultures in the basins of the river. Nile, Tigris, Euphrates, Ganges, Indus, Amu Darya, Huang He, in the upper reaches of the Yenisei, where agriculture first arose.

The process of domestication of wild animals is not over yet. At present, spotted deer, arctic foxes, sables, foxes, nutrias, red deer, elk, etc. are in the transitional stage from wild to domestic animals. this case to establish the centers of their domestication is not particularly difficult: the domestication of these animals is carried out, as a rule, in the areas of their modern distribution.

Practical part

1. On the contour map, plot the centers of origin of cultivated plants according to Vavilov and Zhukovsky) (see figures.).

2. Analytics: give a brief comparative characteristic centers - arbitrarily .

3. Describe two cultivated plants (see plan).

Primary centers according to Zhukovsky:

1 - Sino-Japanese 7 - Mediterranean

2 - Indonesian- 8 - African

Indochinese 9 - Euro-Siberian

3 - Australian 10 - Central American

4 - Hindustani 11 - South American

5 - Central Asian 12 - North American

6 - Western Asian

Similar information.

There are 4 types of tasks in the proposed practical work. in the first task, compare plants with their centers, the second task is to work with a contour map. the third task is to compare the centers of cultivated plants with a description of the geographical location. The fourth task is to give a complete answer to the questions posed.

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"Practical work on the topic: "Centers of origin of cultivated plants" Grade 11"

Practical work on the topic:

"Centers of origin of cultivated plants" Grade 11

Exercise 1. Sort the plants into centers (each option distributes all 48 plant names to their centers).

Task 2. Working with the map . On the contour map, mark all the centers of origin of cultivated plants, indicate the geographical location of the centers.

Task 3.Fill the table. Match centers with geographic location and cultivated plants.

Ethiopian Highlands of Africa

Southern Mexico

Task 4. Answer the questions with full and detailed answers.

1. Why do most cultivated plants propagate vegetatively?

2. Why are breeders trying to create polypoid plants?

3. What is the essence of the law of homological series in the hereditary theory of N.I. Vavilov?

4. What is the difference between domesticated plants and cultivated ones?

5. For what purpose are mutagens used in breeding?

ANSWERS TO PRACTICAL WORK.

Table 1. Centers of origin of cultivated plants (according to N.I. Vavilov)

If you set the task: "Name the centers of origin of cultivated plants," then many people who are not associated with hybridization will not be able to cope with it. The article contains explanatory information.

Terminology

The centers of origin of cultivated plants are special geographical "foci". They concentrate the genetic diversity of agricultural varieties. Centers of origin are primary - these include areas where wild and domesticated forms originally grew, and secondary. The latter are the centers that were formed from the subsequent distribution of semi-cultivated, cultivated plant species and their further selection.

Historical information

Such a phenomenon as crop production arose long before the advent of our era. Initially, development took place, regardless of the types of surrounding flora, in five geographically isolated territories of the planet. In general, the floristic structure of the species that were attempted to be domesticated was endemic to most areas. This forced the use of local flora. Human civilization continued its development... The heyday of sea and land communications between peoples living in different geographical areas began. These processes were able to accelerate the spread of fruits and seeds of endemic domesticated plants. For this reason, it is not at all easy to establish the homeland of a particular cultural species. The progress of domestication, which took place in different geographical conditions of certain territories, was subject to the laws of evolution. For example, plants experienced such phenomena as random crossing, a multiple increase in the number of chromosomes against the background of natural hybridization. Mutations of various types also took place.

Research Conclusions

On the basis of the discovery of Charles Darwin about the geographical centers of origin of different biological species, a certain direction was formed in the study of hybridization. In the 19th century, A. Decandol published his research, in which he singled out the centers of origin of cultivated plants and the territories of their initial occurrence. In his writings, these areas referred to vast continents, as well as to other large-scale areas. For almost fifty years after the publication of Decandole's work, knowledge of the centers of origin of cultivated plants has expanded significantly. Several monographs have been published that have covered agricultural varieties different countries, as well as materials about individual species. Later, N. I. Vavilov took up this issue in earnest. Based on information about the world's flora resources, he identified the main centers of origin of cultivated plants. There are seven in total: East Asian, Mediterranean, Central American, South Asian, Southwest Asian, Ethiopian, and Indian. In each of them, a certain percentage of the entire variety of agricultural varieties grows.

Making adjustments

Some researchers, such as A. I. Kuptsov and P. M. Zhukovsky, continued the work of N. I. Vavilov. They made certain changes to his conclusions. Thus, the South-West Asian center was divided into the Central Asian and Central Asian ones, while Indo-China and tropical India act as two independent geographical centers. The Yellow River basin is considered the basis of the East Asian center. Previously, it was the Yangtze, but the Chinese, as a people engaged in agriculture, settled in this territory much later. New Guinea and Western Sudan were also singled out as areas of agriculture.

Note that fruit crops, including nut and berry crops, have an extensive habitat. They extend far beyond the borders of the territories of origin. This phenomenon is more consistent with the teachings of Decandole than with the others. The reason is justified mainly by forest origin, and not foothill, which corresponds to field and vegetable varieties. Selection is also key. The centers of origin of cultivated plants are now more clearly defined. Among them, the European-Siberian and Australian centers are distinguished. The North American center was also formed.

General information

In the past, certain plant species were introduced into cultivation outside the main foci. However, their number is relatively small. Previously, the main centers of ancient agricultural cultures were considered to be the valleys of the Nile, Euphrates, Tigris, Ganges and other large rivers. According to Vavilov's research, many agricultural varieties appeared in the mountainous zones of the tropics and subtropics. The original centers of origin of cultivated plants are closely related to floristic diversity and ancient civilizations.

Chinese section

This region includes the mountainous territories of the western and central parts of the country, with low-lying areas adjacent to them. The basis of this center is the latitudes of the temperate zone, located on the Yellow River. The local conditions are characterized by such characteristics as moderate, very high degree of moisture and high temperature regime. The hearth is a natural habitat for soybeans, angular beans, kaoliang, millet, rice, oats, paisa, chumiza, Tibetan barley and many other plants.

Southeast Asian section

The Indo-Malaysian center of origin of agricultural crops is complemented by the Indian region. It includes such territories as Indochina, the entire Malay Archipelago and the Philippines. The Hindustan and Chinese centers of origin of cultivated plants had some effect on given area. Local conditions characterized by year-round vegetation, extremely high humidity and temperature. The area is a natural habitat for nutmeg, cardamom, orange, bergamot, black pepper, mangosteen, betel, lime and many other species.

Indian section

It is also called the Hindustan Hearth and includes the Indian state of Assam, Burma, and the entire Hindustan peninsula, except for the northwestern states of India. The local climate favors a long growing season, high level temperature and humidity. The area was influenced by the Indo-Malay center. Citrus fruits, rice and many other representatives of the flora grow in this area.

Central Asian section

This focus includes the lands of the Western Tien Shan, Tajikistan, the northern part of Pakistan, Uzbekistan, Afghanistan and the northwestern part of India. Local conditions are characterized by a moderate growing season, high temperatures with strong seasonal and daily fluctuations, and very low levels of moisture. This area has experienced strong impact Western Asian and Chinese centers. For this reason, it is a secondary focus for most of the local fruit varieties.

Western Asian section

The outbreak is located in its region includes the territories of mountainous Turkmenistan, the entire Transcaucasia, Iran and inner part Asia Minor. The local climate is characterized by long dry periods, high temperatures and very low levels of humidity. This area has experienced the impact of the Central Asian and Mediterranean centers. The boundaries of these three foci are closely intertwined, so it is almost impossible to establish them.

South American Center of Origin of Cultivated Plants

These territories include the mountainous zones and plateaus of Bolivia, Ecuador, Colombia and Peru. Local conditions are characterized by insufficient moisture and very high temperature. The Central American center had some influence on this area.