WEEDS CONTAMINATION OF A WINTER RYE CROPS DEPENDING ON WAYS OF TILLAGE IN THE CONDITIONS OF TRANSITION TO ORGANIC FARMING

The winter rye, as well as to other crops of continuous sowing which effectively suppress weeds in organic farming possesses a special role. This culture is sensitive to the competition of weeds only at early stages of development. Starting from phase of shooting it acts as an important factor of counteraction of a weed invasion in the field. The problem of our researches consisted of studying the contamination degree of a winter rye crops which was grown up without use of fertilizers and means of plants protection, depending on main ways of tillage in a crop rotation. On the basis of 3-year-old observations it was established that at prolonged use of moldboardless main ways of tillage the contamination of crops at a seedling stage of a winter rye significantly grew – by 55.1 % at usual and for 36.7 % at small moldboardless tillage in comparison with moldboard tillage. At the same time, the air-dry mass of weeds was higher on 27.7 and 43.0 % concerning control, respectively. For harvesting period of culture on option of usual moldboardless tillage to depth 18–20 cm quantity of weeds for 46 %, and on option of small moldboardless – for 30.2 % was higher, than on plowing. The greatest contamination by weeds of crops for observation years is recorded at continuous moldboardless tillage on depth of 18–20 cm. The analysis of group structure showed significant dominance of the wintering and winter weeds over other groups irrespective of a main tillage way, though the increasing tendency of summer late and rootstock weeds part at usual moldboardless is traced. The winter rye successfully competed with weeds. Phytosanitary inspection of fields did not record oppression of culture before grain-harvesting works. On the best areas of soil fertility which were created at prolonged use of usual and small moldboardless main ways of tillage the productivity was higher on 1.7 and 3.9 c/hectare or 9.3 and 21.2 %, respectively in comparison with control. Perspectives of further researches are connected with specification of a winter rye productivity models which is grown up in the system of traditional and organic farming.