[en] The effect of high-position grafting of apple trees on cold-resistance and high yield was significant. The yields of varieties 'Huantaiping' etc. grafted on high posotion after 7 years were increased by up to 100 kg per plant in comparing with that grafted on low position. The photosynthetic products synthesized by high grafting trees and ³²P absorbed by roots were studied by measuring the radioactivity of ³²P and ¹⁴C, and by autoradiograph. The distribution of nutrient in various organs was affected by graft union, and the accumulation of photosynthetic produts in fruit bearing portions was in favour of the differentiation of flowers and the formation of fruits