矮砧苹果树氮素含量变化的研究

STUDIES ON THE CHANGE OF NITROGEN CONTENT OF THE APPLE ON DWARFING STOCK

矮砧苹果树之所以生长弱、长枝少、短枝多、树体矮化与早春根系以及发育枝内含氮量较低,主要依赖贮藏氮素,供氮不足等因素有关。叶内含氮量较高,有利树体的光合作用。果实发育中期,果内含氮量较高,有利果实体积增大和品质的提高,矮砧苹果树更应该注意生长前期根外追肥和秋季施氮,以保证贮藏氮素的积累。

The growth of apple on M 9 stock depends on the store nitrogen nutrient chiefly. The growth inhibited in previous peroid results from poor root absorbability, water and nutrient supply insufficient. The lower level of nitrogen in shoot effects on shooting activity while higher level promotes photosynthesis. Whereas higher nitrogen content in fruit contributes to enlarge fruit size and improves its quality. To sprage nitrogen in previous peroid and to fertilize in autumn for the apple on dwarfing stock should be paid more attention and this easures to accumulate nitrogen nutrient.