缺铁黄化对酥梨叶片营养元素含量和光合特性的影响

Effect of Iron Deficiency on Contents of Nutrient Elements and Photosynthetic Characteristic of Leaves in Pear Trees

对不同缺铁黄化程度酥梨叶片的矿质营养元素含量、光合色素和光合特性的研究 ,结果表明 ,随着缺铁黄化程度的加大 ,叶片的 P、K、Cu、Zn、B含量显著增加 ,N、Mg、Fe变化不明显 ,Ca、Mn、活性 Fe明显减少 ,全 Fe含量与缺铁黄化程度关系不明显 ,活性 Fe是叶内铁营养水平的指标。叶绿体各色素含量随黄化明显下降 ,a/b增大 ,叶绿素 /类胡萝卜素减小 ,其比值可作为缺铁的诊断指标。缺铁黄化还使 Pn下降 ,Ci增大 ,E、GS变化不明显。

Analysis on the contents of minerals, chloroplast pigments and photosynthetic characteristics with the degree of iron deficiency showed that with the yellow degree increasing the contents of P,K,Cu,Zn and B remarkablely increased, the contents of Ca, Mn and active Fe decreased. The contents of N, Mg and total Fe had not obviously changed, there was a close relationship between active Fe and the degree of iron deficiency. The contents of chloroplast pigments decreased obviously, a/b increased, chlorophyll/cartinoid decreased and its could be an index to diag iron deficiency. Net photosynthetic rate decreased. Intercellular CO 2 concentration increased. Transpiration rate and stomatal conductance had not obviously changed.