Productivity of sunflower varieties in crop rotation after oil flax on leached chernozem of West Precaucasus

The experimental material on crop rotation with cereals of field trials conducted in VNIIMK in 2005-2008 is analyzed and resulted. The different preceding crops of sunflower, such as winter wheat (now widely used in cultivation) and oil flax (earlier was not considered as preceding crop for sunflower) were studied. For the trial there were taken sunflower varieties of different maturing group: super early (SUR), early (Buzuluk) and middle (Lakomka, Master). The obtained data showed that at sunflower planting after oil flax seed yield and oil yield of super early sunflower variety (SUR) is higher on 24.8 and 25.2 % then after winter wheat, seed yield and oil yield of early sunflower variety (Buzuluk) is higher on 19.2 and 16.4 %, and of middle varieties (Lakomka, Master) - on 10.0 and 7.5 % and 9.0 and 6.2 %, respectively. But seeds oil content of all varieties is lower on 1.0-1.5 % at sunflower planting after oil flax in comparison with planting after winter wheat. Oil flax can be recommended as preceding crop for sunflower along with winter wheat at development of crop rotation with crops alternation according to specialization of farm production.