Effects of sowing quantity on production characteristics of Onobrychis viciaefolia and Medicago varia at alpine region in Lintan County

Onobrychis viciaefolia cv. Gansu and Medicago varia cv. Gannong No.1 were planted with different sowing quantity (O. viciaefolia cv. Gansu with 70, 100 and 130 kg/ha and M.varia cv. Gannong No1 with 7,10 and 13 kg/ha) in the early spring on the terraces of 2 590 m above sea level at Yeliguan Town in Lintan County. During the study phenology of two varieties was observed; plant height, growth rate, yield, nutrient dynamics and winter survival rate were measured; and the productivity and adaptability of them on alpine region were also discussed. The results showed that the winter survive rate of two varieties was over 95% although they were not complete their life cycle in the sowing year. Yields of fresh forage and hay of the O. viciaefolia cv. Gansu the sowing quantity (100 kg/ha) were the highest, which were 11 734.0 and 3 357.8 kg/ha, respectively. Yields of fresh forage and hay of the M. varia cv.Gannong No.1 at 13 kg/ha were the highest, which were 5 217.5 and 1 690.9 kg/ha, respectively. There was little effect on the nutrient contents of two varieties at the different sowing quantity. However, crude protein, crude ash and phosphorus contents tended to decrease, while crude fiber content increased gradually after August 5th. O. viciaefolia cv. Gansu and M. varia cv. Gannong No.1 with the sowing quantities at 100 and 13 kg/ha respectively had the high performances and strong adaptability, so they can be used as forage at Lintan in the future.