TY JOUR TI LEGUMES AND LEGUME-CROP PERENNIAL GRASSES - A CONSTITUENT PART OF ORGANIC FARMING OF THE REPUBLIC OF TATARSTAN KW organic farming KW alfalfa KW goat’s rue KW meadow clover KW legume bacterium KW biological nitrogen KW mobile phosphorus KW exchange potassium KW undesirable plant KW arable land productivity JO Vestnik of Kazan State Agrarian University AU Khismatullin, M.. PY 2019 IS 14 PB Kazan state agrarian University