Comparative productivity of legume and gramineous mixtures in the Tula region

The legume-grass mixtures were studied in 1999-2010 at the Tula Scientific Research Institute of Agriculture. These grass mixtures were destined for the foundation of the cultivated hayfields and pastures in the gully-beam systems of the Tula region under radioactive contamination. It was established, that the botanical composition of the grass mixtures was changed during the first six years of their cultivation strongly. Eastern galega was the best of the legume-grass mixture in the cultivation variant without fertilizers. Awnless brome supplanted eastern galega in the variant with applying N60P60K60. Variegated alfalfa ( Medicado varia Mart .), and birdsfoot deer vetch ( Lotus corniculatus L. ) were quite resistable in the double mixtures. The grass mixture of the Eastern galega ( Galega orientalis Lam. ) and awnless brome (Bromopsis inermis Leyss) was established as one of the best species of the productivity of green mass, air-dried matter, content of crude protein and exchange energy. Applying N60P60K60 provided rise in green mass yield by 30% compared to the control variant, by 2.4 t/ha of dry mass, by 0.36 t/ha of crude protein, by 23.6 GJ/ha of exchange energy. It is established that perennial legumes carry out approximately 2-3 times more 137Cs than cereals. In this case, in the Eastern galega for 4th and more years of life, the accumulation coefficients of 137Cs are reduced, which is due to the peculiarities of the root system. Old-growth Eastern galega (5 and more years) accumulated of 137Cs nearly to 2.5 times smaller compared to young plants (2-3 years). 137Cs content in air-dried matter of legume-grass mixture did not exceed the Standart for hay (400 Bq/kg) under radioactive contamination.