【摘要】 以‘牛心李’成龄树为试材测定了不同类型枝条和树体部位的净光合速率 (Pn)。结果表明 ,不同类型枝条叶片 Pn存在一定差异 ,短果枝叶片 Pn显著高于其他类型枝条叶片 Pn;在同一果枝上 ,果实上位叶具有最强的光合性能 ,果实的存在促进叶片 Pn提高 ,且显示出源 -库关系只在较近距离时作用显著 ;树体不同部位及不同层次叶片 Pn与光合有效辐射密切相关更多还原

【Abstract】 Pn of leaves of different branches and tree-crown location was measured.Te results showed the Pn was different in all kinds of branches,which the Pn of short fruit branches was much higher than the other branches.In the same branches,the upper leaves possessed the strongest photosynthetic characteristics because of fruit existence,which indicated the relation of source and store was obvious at closer range.In addition Pn of the leaves of different tree-crown and levels was closely related with PAR.$$$$更多还原