Abstract: Two and three-year-old apple trees were used as the test materials, and the two kinds of width of nutrition zone (1.9 and 2.5 m) was set up. Through the interaction test of two factors, the interaction effect of fruit trees and potatoes in different intercropping modes of young orchard was studied. The results showed that for 2-year-old fruit trees, different width of nutrition zone had no significant effect on the growth of fruit trees, but had significant effect on potato yield, when the width of nutrition zone was 1.9 m, the yield of potato was significantly higher than that of 2.5 m. Therefore, the optimum intercropping density for 2-year-old orchard was 0.70 m×0.35 m. For 3-year-old fruit trees, when the width of nutrition zone was 1.9 m, the yield of potato was significantly higher than that of 2.5 m, but the plant height, trunk diameter and branching number of fruit tree were significantly smaller than that of 2.5 m. Potato intercropping in young orchard needs to ensure the growth of fruit trees. Therefore, intercropping potatoes in 3-year-old apple orchard, the best intercropping density was 0.50 m×0.35 m.

Key words: young apple orchard, intercropping, potato, inter space width, interaction effect