Len-dolgunets conducts the origin - from the centers of ancient agriculture of subtropical and moderate belts where it was cultivated for receiving oil. Advance of flax to more northern areas with a soft and humid climate promoted the best development of stalks that led to formation of new types of the flax-dolguntsa giving valuable fiber, and as podbochny production — as well oil from its seeds.
The various cultural plants relating to fibrous, oil-bearing, sugar-bearing crops which are used as raw materials for a number of industries are their part: oil milling,, textile, etc. therefore nature of territorial concentration of the main commercial crops is closely connected with features of formation of raw zones of the overworking enterprises which are a part of the distinguished types of agrarian and industrial complex
Grain krupyany crops (millet, buckwheat, rice) occupy 3 — 4% of all cultivated areas of grain crops. They have the different areas of a caused by ecological features of each of krupyany cultures.
The agriculture consists of two main parts: plant growing (agriculture) and animal husbandry. About 40% of gross output of agricultural production are the share of plant growing on average.
High potential efficiency of corn, ability it to extract nutrients from the soil and sharply to increase an at application of fertilizers, especially on water-permeable and soils, drew to it attention of many geneticists and selectors. Its high-yielding hybrid and early ripe types and grades were as a result created.
Now it is possible to note the following tendencies in development of family farms: increase in scales of application of wage labor; transformation of farmers into managers of farms; emergence of informal cooperation between farms.
The corn has important fodder value, is used in the food industry. This culture of a tropical origin starts growing quite high temperatures (10 °), the period of its vegetation will extend till 160 days, she badly transfers frosts (to — 2 °), needs large supplies of heat. For ripening of grain of early ripe grades it is required 1 — 2200 ° biologically active temperatures, and for more productive average and late-ripening grades-2500-2900 °. Thus the corn of a, especially in the first phases of vegetation, but a lack of moisture before ejection of whisks considerably reduces productivity.
The farmers of the second wave who were generally leaving collective farms and state farms preferred sites considerably to the bigger area (not less than 50-60 g, however by this moment the competition for the earth became aggravated also much it was not succeeded to receive an allotment of the desirable size any more.
The cultural plants coming from a moderate belt or vegetiruyushchy during the cold period in a subtropical belt are significantly less exacting to heat stocks, have shorter period of vegetation, start growing at low temperatures, are steady against frosts. Combinations of the indicators characterizing the relations of cultural plants to conditions warm and moisture security in various phases of vegetation form a basis for development of bioclimatic classifications of cultures.
Many agroecological signs of cultural plants (the requirement to conditions of the thermal and light mode, moistening during the different periods of vegetation, chemical reaction of soils, etc.) are connected with the centers of their. So, tropical plants begin growth at quite high temperatures (10 — 15 °), have the extended period of vegetation and demand large supplies of heat at all stages of development. These are the cultures of short day which are characterized by the greatest consumption of moisture in the middle of the period.
Millet occupies rather big spaces as a part of krupyany cultures. The beginning of growth occurs at quite high temperatures (10 — 12 °), the culture is sensitive to frosts and at the same time differs in high drought resistance, has low coefficient of a transpiration (To = 250 — 30, well transfers weak salinization of soils, but reacts to sour reaction of the soil environment.