If you set the task: "Name the centers of origin of cultivated plants", then many people who are not connected with hybridization will not be able to cope with it. The article contains explanatory information.
Terminology
Centers of origin of cultivated plants are special geographical "foci". They concentrate the genetic diversity of agricultural varieties. The centers of origin of cultivated plants are primary - they 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 onset of our era. Initially, development took place, regardless of the types of surrounding flora, in five geographically isolated territories of the planet. Basically, the floristic structure of the species that tried to domesticate was endemic to mostareas. This forced them to resort to the use of the local flora. Human civilization continued its development… The period of sea and land communications flourishing between the peoples living in different geographical areas. 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 various 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. There were also mutations of various types.
Research Conclusions
Based on the discovery of Charles Darwin about the geographical centers of origin of different biological species, a certain direction has been 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 were published that covered agricultural varieties of different countries, as well as materials on individual species. LaterN. I. Vavilov took up this issue in earnest. On the basis of 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. Each of them grows a certain percentage of the entire variety of agricultural varieties.
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 Near-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 have also been identified as farming areas.
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. Amongthey are distinguished by the European-Siberian and Australian centers. 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 temperate zone, tropics and subtropics. The original centers of origin of cultivated plants are closely related to floristic diversity and ancient civilizations.
Chinese section
This area includes the mountainous areas of the western and central parts of the country, with adjacent lowland areas. 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 a moderate growing season, a very high degree of moisture and a high temperature regime. The hearth is a natural habitat for soybean, angular bean, kaoliang, millet, rice, oats, paisa, chumiza, Tibetan barley and many other plants.
Southeast Asian section
The Indo-Malaysian home of agricultural origin complements the Indian region. It includes such territories as Indochina, the entire Malay Archipelago and the Philippines. Hindustani andThe Chinese centers of origin of cultivated plants had some impact on the area. Local conditions are characterized by year-round vegetation, extremely high humidity and temperature. The area is a natural habitat for nutmeg, clove, cardamom, orange, bergamot, black pepper, mangosteen, betel, lime and many more.
Indian section
It is also called the Hindustan hotbed and includes the Indian state of Assam, Burma and the entire Hindustan peninsula, with the exception of the northwestern states of India. The local climate favors a long growing season, high levels of temperature and humidity. The area was influenced by the Indo-Malay center. Citrus fruits, sugarcane, 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 a strong impact of the Near East and Chinese centers. For this reason, it is a secondary focus for most of the local fruit varieties.
Anterior Asian section
The outbreak is located in Western Asia. Its region includes the territories of mountainous Turkmenistan, the entire Transcaucasia, Fertilecrescent, Iran and the interior of 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 centers are closely intertwined, so it is almost impossible to identify 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 temperatures. The Central American Center has had some impact on this area.
