苹果缺铁失绿症的矫正途径及其机理

Approach to the mechanism of correcting iron dificicency chlorosis in apple trees

为了矫正石灰性土壤上存在的果树缺铁失绿症,进行了该试验。根系输液条件下,N-Fe能够在短时间内有效地矫正果树缺铁失绿症。红色邻二氮杂菲铁示踪结果表明:二价铁肥根系输液以二价态由根被动吸收、运输到根、茎、叶和主脉内,运输部位是靠近形成层的木质部。室内营养液培养的西府海棠苗用59Fe示踪结果表明,断1、2、3条根59Fe在叶中分配的比例分别为57.9%、63.6%和68.0%。树干强力高压注射铁肥以二价铁主要沿中央木质部的导管运输,大部分向下运往根系,致使根中贮存大量的铁,向上运输稍难。矫正缺铁失绿症的速度比根系输液慢,但由于根中贮存大量的铁,持效期较长。铁可以通过枝条和叶片进入树体并且运输。

The study was carried out to crrect the chlorosis of fruits in lime soil. The iron deficiency chlorosis of fruit trees can be corrected in a shorter time with root injection when N - Fe was entered into the tree. The trace of red O - phenanthroline Fe indicated： Fe^2＋ was absorbed by roots and transported to stem, leaves and main vein when iron feritilizer was root injected. Fe^2＋ was transported along xylem near cambium. Trace of ^59Fe with Malus micromalus cultured in nutrient solution under controlled conditions indicated： ratio of iron distributed in leaves by cutting one, two, three roots were 57.9 %, 63.6 % and 68.0 %, respectively. The iron fertilizer by high - pressure trunknjection indicated：Fe^2＋ was transported along the central xylem. Most of Fe^2＋ was transported and stored in roots. It was a little difficult for Fe^2＋ to be transported upto leaves. Regreening of iron deficiency chlorosis trees was slower but the effect of correcting iron deficiency chlorosis lasted longer when trunks were rejected with iron fertilizer than iron fertilizer was root injected. Iron could be absorbed and transported by branch and leaves.