Breeding of new variety of Medicago sativa cv. Caoyuan No.4

Medicago sativa cv. Caoyuan No.4 with anti-thrips was selected through three cycles using insect resistance identification, superior clones, and combination of insect resistant identification and cooperation equipped with basic groups (registration number: 477). Root of the variety was erect with horizontal growth root. Stem was erect with setae. Leaf was three compounds with surface setae. Flower was purple. Pod was spiral of 2 to 3 times. Thousand grain weight was 1.86~2.35 g. The variety was high insect resistance (hazard point coefficient: 0.26, and pest index: 0.33), drought resistance, cold resistance, and barren resistance. It can be cut three times, average hay yield was 12 000~16 000 kg·ha-1, and seed yield was 230.90 kg·ha-1 in Hohhot regions. The crude protein content was 19%. This alfalfa specie was suitable for the cultivation in serious thrips harm regions as southern provinces of the north China.