Ciba-Geigy Ltd., Agrochemicals Division, Basel, Switzerland.
Plant Physiol. 1974 Oct;54(4):582-5. doi: 10.1104/pp.54.4.582.
The Fe requirements of four monocotyledonous plant species (Avena sativa L., Triticum aestivum L., Oryza sativa L., Zea mays L.) and of three dicotyledonous species (Lycopersicum esculentum Mill., Cucumis sativus L., Glycine maxima (L.) Merr.) in hydroponic cultures were ascertained. Fe was given as NaFe-EDDHA chelate (Fe ethylenediamine di (O-hydroxyphenylacetate). I found that the monocotyledonous species required a substantially higher Fe concentration in the nutrient solution in order to attain optimum growth than did the dicotyledonous species. Analyses showed that the process of iron uptake was less efficient with the monocotyledonous species. When the results obtained by using chelated Fe were compared with those using ionic Fe, it was shown that the inefficient species were equally inefficient in utilizing Fe(3+) ions. However, the differences between the efficient and the inefficient species disappeared when Fe(2+) was used. This confirms the work of others who postulated that Fe(3+) is reduced before uptake of chelated iron by the root. In addition, it was shown that reduction also takes place when Fe is used in ionic form. The efficiency of Fe uptake seems to depend on the efficiency of the root system of the particular plant species in reducing Fe(3+). The removal of Fe from the chelate complex after reduction to Fe(2+) seems to present no difficulties to the various plant species.
在水培条件下，确定了 4 种单子叶植物（燕麦、小麦、水稻、玉米）和 3 种双子叶植物（番茄、黄瓜、大豆）的铁需求。铁以 NaFe-EDDHA 配合物（Fe 乙二胺二（O-羟基苯乙酸））的形式提供。我发现，与双子叶植物相比，单子叶植物需要在营养液中摄入更高浓度的铁才能达到最佳生长状态。分析表明，铁的吸收过程在单子叶植物中效率较低。当使用螯合铁的结果与使用离子铁的结果进行比较时，表明低效的物种在利用 Fe(3+)离子方面同样低效。然而，当使用 Fe(2+)时，有效物种和低效物种之间的差异消失了。这证实了其他人的工作，他们假设 Fe(3+)在根吸收螯合铁之前被还原。此外，还表明当铁以离子形式使用时也会发生还原。铁的吸收效率似乎取决于特定植物物种根系还原 Fe(3+)的效率。还原后从螯合物复合物中去除铁似乎不会给各种植物物种带来困难。
