关键词: 苹果, 根域, 交替灌水, 定位灌水, 生长, 生理特性

Abstract: Three-year old‘Royal Gala’apple（Malus domestica Borth.）trees［grafted onto（M. robusta Rehd.）］grown in split-root pots were used to study that effects of partial root-zone alternative irrigation （PRAI）and partial root-zone located irrigation（PRLI）on shoot growth and leaf physiological characteristics. The results indicated that in PRAI，large irrigation rate significantly improve shoot growth and make autumn shoots growth early，and the second growth of new shoots were observed except the treatments of 1/4，2/4，and 3/4 root-zone irrigated by 500 mL and 2/4 root-zone irrigated by 750 mL. In contract，there is no significant difference on shoot growth between treatments，and shoot growth was little in all the treatments in PRLI. Leaf water potential and stomatal conductance had no difference in PRAI and PRLI. However，those were more stable in PRAI than PRLI. Therefore，shoot second growth was determined by irrigation rate，and leaf physiological characteristics were effected by irrigation root-zone. The second growth of shoots can start when partly root-zone（1/4 or 2/4 root-zone）was irrigated. However，their growth was retarded when 3/4 or 4/4 root-zone was irrigated and the irrigation rate was more than 750 mL. PRAI can save much more water than PRLI with maintaining physiological characteristics of apple tree. In this study，irrigating 2/4 root-zone with 750 mL water in PRAI was optimal according to regulation of shoot growth and saving water and maintaining leaf physiological characteristics.

Key words: apple, root-zone, PRAI, PRLI, growth, physiological characteristics