Preliminary screening of appropriate grass species and seeding rate for orchard in Shenyang Area

In order to screen appropriate grass varieties and seeding rate for orchard in Shenyang area, three different forages including alfalfa (Medicago sativa cv. Zhaodong), white clover (Trifolium repens cv. Rivendel) and red clover (T. pratense cv. Renegade) were interplanted with different seeding rates in apple orchard. The winter surviving rate, grass yield, growth rate and crude protein were investigated to determine appropriate grass varieties and seeding rate. The results indicated that alfalfa with natural winter surviving rate of 100% performed better compared with white clover and red clover with highest winter surviving rate of 12% and 48%, respectively, which was appropriate in the orchard of this region. Alfalfa can be mowed three times throughout the year. The yield of hay, growth rate and the average crude protein of alfalfa were highest with the medium seeding rate (15 kg·hm-2) which were 15 783.74 kg·hm-2, 2.63 cm·d-1 and 19.79%, respectively. Alfalfa with the low seeding rate have the highest average of net assimilation rate which was 3.32 g·m-2·d-1. Alfalfa was appropriate grass variety for orchard in cool area and the appropriate seeding rate was 15 kg·hm-2 based on the yield of hay, growth rate and the average crude protein.