【作者】 孙俊； 章镇； 盛炳成；

【Author】 Sun Jun, Zhang Zhen, and Sheng Bingcheng (Deparetment of Horticulture, Nanjing Agricultural Unversity, Nanjing 210095)

【机构】 南京农业大学园艺系；

【摘要】 本文回顾了目前国内外在落叶果树氮的贮藏、循环和利用及秋季氮的吸收等方面的研究现状。秋冬季节,氮以特异性贮藏蛋白质和其它形式贮藏在树体不同部位,为下一个生长季节,尤其是早春新器官的建造及时提供养分。这种作用不受当年根系从土壤中吸收氮多少的影响。生长季节,氮主要以RUBISCO和其它形式存在于叶片中至秋季落叶时,回撤到树体贮藏氮部位,为下一个季节的生长贮备营养,秋施氮对这种营养贮藏有促进作用,从而提高次年春季氮的重新利用效率。更多还原

【Abstract】 The processes of internal cycling of nitrogen are reviewed and discussed in relation to management of deciduous fruit trees. In deciduous fruit trees nitrogen is stored during the winter predominantly as protein in the bark, and remobilised in the spring when the buds break. During the summer, nitrogen is stored in the leaves and withdrawn during senescence. Remobilisation of nitrogen in spring provides nitrogen for leaf growth before rapid root uptake occurs and so is unaffected by the nitrogen supply to soil. Fertilizing in spring, therefore, increases growth and storage capacity but has little effect upon the efficiency of remobilization. However, appling fertilizer in the autumn can increase the partitioning of nitrogen to roots and provide more for internal cycling than when taken up during the summer.更多还原