Study on productivity of Medicago sativa with different agronomic measuresin blacksoil region of midtempenate agriculture zone

In order to improve the productivity of Medicago sativa in blacksoil region of midtemperature agriculture zone. Experiments were conducted in terms of variety, fertilization and sowing time. Results showed that the yield of M.sativa was 9 826.3-12 191 kg/hm2 under the integration of current techniques. The productivity of M.sativa could be improved if the related techniques were optimized. One of optimized techniques was applying the 15 cm width of ridge that could increase the number of seedlings and the branches of the plants. Another way was to use fast grow and cold tolerant variety such as Longmu 801. Fertilization of P2O5 (138 kg/hm2), K2O (150 kg/hm2) and manure (30 000 kg/hm2) could increase activation of soil and the roots growth. The fourth way was sowing early in summer (July 5th) to improve the productivity.