关键词: 苹果, 砧木, 品种

Abstract: ‘Qing Ai 3’is a new apple semi-dwarfing rootstock selected from the M₉ seedlings in 1978. Not only its crown but also its growth is medium. Grafting on the inter stock，the Fuji tree fully produced at 3 years old. The average yield of the tree of 7–14 years old is 42 270 kg · hm^-2，while that on M₂₆ is 34 785 kg · hm^-2，which shows it has high-yield character. The fruits have good quality and colour. The soluble solids content of Fuji grating on the inter stock is 14.3%，the hardness is 7.8 kg · cm^-2，and the fruit index is 0.87，which is equal to M₂₆.The Fuji tree dwarfing on the inter stock in high-yield year has a 3.83 m height and a 3.57 m crown diameter，which is 30% more than that of M₂₆. Therefore，‘Qing Ai 3’belongs to a semi-dwafing rootstock. It has straight trunk which can stand without pillars，which is suitable for the application in the main apple production area such as Shandong，Hebei，Shanxi and Shaanxi.

Key words: apple, rootstock, cultivar