Enhancement of Cadmium Phytoremediation Potential of Helianthus annuus L. with Application of EDTA and IAA

Abstract

The aim of the current study was to assess the cadmium (Cd) phytoremediation potential of Halianthus annus L. that was exposed to 50, 100, and 150 mg/kg of cadmium for 15, 30, and 60 days with application of EDTA (Ethylenediaminetetraacetic acid) in the soil and IAA (indole acetic acid) as a foliar spray. The results indicated that the concentration, duration of exposure, and amount of Cd affect the phytoremediation potential. The maximum Cd was observed at 60 days (32.05, 16.86, and 10.63%) of Cd application, compared to 15 (2.04, 0.60, and 1.17%) or 30 days (8.41, 3.93, and 4.20%, respectively), in a dose-dependent manner. The application of EDTA in the soil and foliar IAA enhanced the Cd accumulation in the plants at 15, 30, and 60 days of exposure, with maximum accumulation at 60 days. Exposed plants with foliar IAA application showed 64.82%, 33.77%, and 25.84% absorption at 50, 100, and 150 mg/kg, respectively. Apart from higher absorption, the cadmium translocation to the edible part of the plants ceased, i.e., the seeds had 0% accumulation. The interesting fact was recorded that efficient phytoremediation was recorded at 15 days of exposure, whereas maximum phytoremediation was recorded at 60 days of exposure. To minimize the stress, the host also produced stress-related metabolites (i.e., flavonoids, phenolics, proline, and sugar) and antioxidants (i.e., catalases and ascorbate peroxidases). From the current evidence, it could be assumed that the use of EDTA and IAA, along with hyperaccumulating plants, could be a possible green method to remediate Cd-contaminated soil efficiently in a short period of time.

EDTA and IAA Ameliorates Phytoextraction Potential and Growth of Sunflower by Mitigating Cu-Induced Morphological and Biochemical Injuries

“…The total copper content in plant biomass boosts with the inclination of metal concentration in the growth medium, showing a multifold accumulation from 0 to 75 mg Cu/kg soil. Similar results were previously recorded in the case of sunflower, brassica, and soybean treated with cadmium, chromium, and arsenic, showing a direct relation between metal levels and exposure duration [ 52 , 55 , 59 , 60 ]. A similar pattern was observed when EDTA was applied to soil.…”

“…Plants exposed for 15 days to Cu stress showed lower accumulation, with the exception of 75 mg/kg of copper, which showed a decline with the passage of time. Except for the plants exposed to 50 mg Cu/kg soil with foliar application of IAA [ 59 ], for which an increase was observed after 30 days of copper exposure. A comparable rise was also documented in the case of 60 days of exposure to copper supplementation, showing an increase up to 50 mg Cu/kg soil; however, a decline was noted in the case of 75mg Cu/kg soil [ 62 ].…”

“…Foliar application of IAA, for example, increases copper accumulation, although a declining pattern was observed with the incline of metal in the soil [ 64 ]. The decline recorded with the duration was due to more copper accumulation and the subsequent harm due to metal stress and successive oxidative stress; it negatively affects the physiological attributes of the host by altering the physiology of the host, lowering the biomass, and, therefore, lowering the phytoremediation potential of the host plant [ 35 , 36 , 59 , 60 ]. Similar arrays were observed in the transfer of metals to the aerial parts of plants and were also documented in the case of the translocation of metals to the aboveground parts of the plants.…”