The effect of the chelated form of iron on its mobility and phytodavailability when applied to the soil

Abstract

In spite of well-known mechanisms of iron consumption by plants from the soil and action patterns of iron ions in the soils, the work to eliminate the deficiency of this trace element in plants is still relevant. The article presents an assessment of the effect of iron (III) chelate complexes with diethylenetriaminepentaacetic acid (DTPА Fe) and ethylenediaminetetraacetic acid (EDTA Fe) on the mobility and availability of iron for plants in soil with a pH close to neutral.  In a model experiment with using of drainage columns, there were established the patterns of iron distribution in the soil and its removal with irrigation water from the root zone of plants (10 cm). Against the background of similar distribution of iron in the soil, a higher content of its mobile forms in the lower layers was noted when using EDTA Fe. The leaching of iron from the soil was confirmed using both DTPA Fe and EDTA Fe. The vegetation experiment revealed the effect of chelate forms on the accumulation of iron in barley plants (Hordeum vulgare L.) during their early growth period (11 days). The iron content in the shoots varied from 120 to 140 µg/g, in the roots – from 233 to 244 µg/g, with a content of 200 µg/g in the control sample. A significant  contribution to the accumulation of iron in barley seedlings was observed at the level of the root system in the experiment with EDTA Fe. Data on the accumulation of iron in barley roots were correlated (r = 0.99) with data on their ash content.