Abyssinian highlands are a secondary center of origin of certain types of wheat and barley, as well as certain varieties of peas and lentils. Furthermore, the birthplace of coffee. From Southeast Asia is multi-row barley. From the same area of the Far East there are peach, apricot, orange, lemon, tea and soy. India - the birthplace of rice and sugar cane, banana and coconut palms.
Of the centers of origin of many forms in the New World mountainous region from Mexico to Guatemala was home to various kinds of beans (Phaseolus), pumpkins (Cucurbita), tobacco, cotton and cocoa, in addition, this area is the primary center of origin of maize. Andes from Colombia to the north of Chile is home to potatoes and tomatoes, as well as a secondary center of origin of maize, tobacco, Virginia and other types of cotton (Gossypium barbadense).
The great variety of soil properties, temperature and rainfall in mountain regions is also aggravating isolation. Therefore, we now understand why the majority of cultivated plants have evolved at an altitude of 500 to 2500 m. Here, apparently, were the first centers of agriculture, which then spread to the lowlands, where he had the most favorable conditions, especially in river valleys. The emergence of large crops in the valleys, made possible by artificial irrigation or draining the land in the basins of the Indus, the Euphrates, the Tigris and the Nile, called for the creation of social formations that could emerge only much later.
Secondary crops. Many species have become useful plants from weeds. They are called secondary cultivated plants. These include rye and oats, which are first, infests wheat and barley. Rye is also now found as a weed in wheat fields in Asia Minor. Similarly, Ica, lentils, flax, and, apparently, also peas were originally weeds. Other plants were first satellite human settlements. They met in a local landfill, the piles of garbage or manure, where they were moved to the gardens to serve as a vegetable seasoning to food. Here we should mention the Chenopodiaceous and Cruciferae, capable of accumulating a lot of nitrates, such as beets and spinach, turnip and mustard greens. Apart from these, as celery and carrots, tomatoes, potatoes, poppies (Papaver), hemp (Cannabis) and stinging nettle (Urtica) were suitable for the growth conditions in nutrient-rich, near housing. Return of many of these useful plants in the field as a commodity or vegetable crops occurred only in relatively recent times. In addition to the barley and wheat, among the most ancient of useful plants are also flax and peas. They were known in Babylon and Egypt, at least 4,000 years BC. e. The oldest discovered the seeds of rye and oats are older than 3000 years. |
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