【摘要】 研究打顶时期、有效留叶数对中上部叶质量及等级构成及的影响。结果表明:随着打顶时间推迟和有效叶片数增加,烟株的株高、节距增加,上部叶叶面积降低;中、上部叶烟碱含量降低,上部叶糖分和钾的积累量增加。留叶数22片左右,现蕾后10d打顶(中心花开放50%左右)可以获得较高比例上等烟叶和经济效益。更多还原

【Abstract】 The effects of topping measures on middle and upper leaf quality and hierarchical structure of flue-cured tobacco was tested.Results showed that the plant height,the distance between internodes increased and upper leaf area decreased with the postponed topping stage and the improvement of apparent leaf number.When the topping date delayed and apparent leaf number increased,the nicotine content in middle and upper leaves decreased,and the carbohydrate and potassium content in upper leaves increased.The optimal economic efficiency and tobacco leaf quality appeared with approximately 22 leaves remained per plant,and topping at 10d after bud.更多还原