Ilker Angin

Organic chelate assisted phytoextraction of B, Cd, Mo and Pb from contaminated soils using two agricultural crop species

This study was carried out to investigate the effects of adding different rates (0, 2.5, 5.0 and 10.0 mmol kg−1) of various organic complexifying agents (OCA) [ethylene diamine tetra acetate (EDTA), diethylene triamine penta acetate (DTPA), citric acid (CA), and humic acid (HA)] on heavy metal availability in the contaminated soils with 100 mg kg−1 B (H3BO3), 400 mg kg−1 Cd (CdCl2), 10 mg kg−1 Mo (Na2MoO4 2H2O) and 100 mg kg−1 Pb(NO3)2 and on the capacity of corn (Zea mays L.) and sunflower (Helianthus annus.) plants to uptake B, Cd, Mo and Pb in heated greenhouse conditions. Corn and sunflower plants were grown at 10,000 plants ha−1. Results indicated that OCA application increased heavy metal availability and uptake by plants. The capacity of OCA to release B, Cd, Mo and Pb in soils planted with corn and sunflower were HA>CA>EDTA>DTPA and HA>EDTA>CA>DTPA, respectively. Of the OCA tested, humic acid was the most effective in enhancing B, Cd, Mo and Pb uptake in both plant species. Significant differences were obtained in both species and plant parts. Plant species tested, sunflower was the most effective in uptake of B, Cd, and Mo. Root heavy metal uptake was greater than shoot heavy metal uptake in both species. As a conclusion, it can be said that humic acid facilitated B, Cd, Mo and Pb phytoextraction may provide effective soil decontamination strategy.

The use of iron (III) ferrocyanide soil amendment for removing salt from the soil surface

Abstract Accelerated soil salinization is a worldwide concern. Our study was carried out to determine the effects of different rates (0, 5, 10, and 15 mmol kg−1) of iron (III) ferrocyanide application to remove salts from the soil. Within two weeks of its application, iron (III) ferrocyanide at 5, 10, and 15 mmol kg−1 removed 12.2%, 26.5%, and 42.9% of the total salts from the soil, respectively. Results suggested that iron (III) ferrocyanide application at 15 mmol kg−1 is one of the most rapid and effective ways to remove substantial amounts of salts from undrained soil (land) where fresh water is scarce.

Ethylenediamine-N,N′-disuccinic acid mitigates salt-stress damages in strawberry by interfering with effects on the plant ionome

This study evaluated the hypothesis that the organic chelant ethylenediamine-N,N′-disuccinic acid (EDDS) mitigates plant damage under salinity, and that this is accomplished by EDDS-induced effects on cation uptake. Damaging effects of salinity on plants often involve inhibited uptake of nutritional cations, such as K and Ca, and excessive accumulation of Na. Therefore, mechanisms that improve uptake of K and Ca, or reduce Na uptake, have a potential for ameliorating salinity damages. Organic chelants increase heavy-metal cation availability at the site of uptake and increase their uptake by the roots or in planta transport. Although organic chelants are routinely used in agriculture to enhance uptake of heavy-metal cations into plants, and for soil bioremediation, their effect on uptake of cation-macronutrients is not known, and neither is their impact on plant function under salinity. In this study, we evaluated the response of strawberry plants to EDDS application (0, 1, 3 and 5 mmol kg soil−1), under six levels of NaCl (0, 3, 6, 9, 12 and 15 mmol L−1). EDDS application under salinity improved vegetative development, as well as reproductive growth and chlorophyll content, with statistically significant interaction between chelant dosage and level of salinity. The mitigation of salinity damage by EDDS occurred at high salinity treatments (from 9 mM NaCl). Application rates of 1–3 mmol EDDS kg−1 were optimal for mitigating salinity effects on reproductive development, but in accordance with the extent of chelant-induced accumulation of the macronutrients K, Ca and P in the leaves, higher application rates (3–5 mmol EDDS kg−1) were required for optimal improvement of vegetative development. These results suggest that EDDS improves plant function under mild salinities by interfering with salinity effects on the plant ionome.