Formation of field crops grain quality depending on predecessors at cultivation in the forest steppe zone of Western Siberia

In the forest-steppe of Western Siberia in the long stationary experiment researches were carried out for define influence of alternation field crops on the yield and quality of grain of spring wheat Omskaya 36 and barley Omsky 90.In the field ex-periments using standard methods were studied in predecessors in the cultivation of crops for different purposes. The product quality was determined ac-cording to the State Standard of Russia R 52554-2006, the State Standard of Russia 5060-86.Math-ematical treatment of information was performed by B.A. Dospekhov (1985). The Links of crop rotations with a clean steam, corn and soybeans proved to be the best on the yield of grain crops. The quality of wheat after major predecessors produced con-sistent to the third class.Soybeans and wheat reg-ularly as a precursor formed a grain of wheat with low nature of the fourth class, the content of protein and gluten was at the level of the second class.Using linear regression analysis revealed the effect of the elements on the fertility of the grain yield of barley, depending on the precursor (r = 0.96).Productive moisture accumulated predeces-sor in the forest-steppe zone is practically no effect on characteristics brewing barley (r = 0.23), while soil nitrogen significantly limited their (r = 0.76). We have received the plural regression equation allow-ing predicting the protein content in grain barley de-pending on the predecessor.