The improved phytoextraction of lead (Pb) and the growth of maize (Zea mays L.): the role of plant growth regulators (GA3 and IAA) and EDTA alone and in combinations

Abstract

This investigation was made to examine the role of gibberellic acid (GA(3)), indole-3-acetic acid (IAA) and EDTA in improving phytoextraction of the Pb and plant growth on Pb added soil. GA(3), IAA and EDTA were applied separately and in combinations. GA(3) and IAA were applied as foliar spray and seed soaking. EDTA was applied in single and split doses. Analysis of the Pb in different parts of plant was carried out using atomic absorption/flame spectrophotometer. EDTA significantly reduced the plant growth and dry biomass, whereas GA(3) and IAA foliar spray increased it significantly when compared with control (only Pb added soil). In combined treatments of EDTA+GA(3) and EDTA+IAA, the growth and biomass was restored, which shows that GA(3) and IAA did compensate the negative effect of EDTA on plant growth. The separate treatments of EDTA, GA(3) and IAA increased the Pb uptake and translocation significantly moreover in combine treatments, synergistic effect was found and remarkable increase in Pb uptake and translocation into shoot was observed. EDTA increased the Pb uptake but declined the biomass; subsequently the total Pb accumulation was decreased in plant. The maximum total Pb was found in combined treatment of EDTA+GA(3). These findings suggest more investigation to find a combination of GA(3) with a very low concentration of EDTA, as in high concentration it causes soil and ground water pollution.

Physiological Studies on the Interactive Effects of Lead and Antioxidants on Carum carvi Plant

“…The inhibitory effect of heavy metals stress induced by Pb growth parameters of Carum carvi is in agreement with the results obtained by some authors using different plants (Chatterjee et al, 2004;Mishra et al, 2006;Sharma & Dubey, 2005;Hadi et al, 2010;Zhou et al, 2010 and Gupta et Non significant (n.s.) at P > 0.05 Significant ( * ) at P ˂ 0.05…”

“…Although lead is not an essential element for plants, it is absorbed easily and accumulated in different plant parts (Sharma & Dubey, 2005). It exerts adverse effect on plant growth (Hadi et al, 2010), changes in chemical composition, antioxidant enzymes system (Gupta et al, 2009(Gupta et al, , 2010 and lower uptake of many minerals. Lead can cause various physiological and biochemical dysfunctions of many physiological and biochemical processes such as nitrogen assimilation and photosynthesis, Dubey, 2005 andSeregin &Kosevnikova, 2008 ).…”

Assessment of lead speciation by organic ligands using speciation models

“…In most cases, the effect of EDTA was many times higher than other organic ligands (Hadi et al, 2010). Saifullah et al (2010) showed that EDTA was more efficient than CA and sulfur in solubilising Pb from the soil.…”

The development dynamics of the maize root transcriptome responsive to heavy metal Pb pollution

“…Roots, as a important organs of plants, that could accumulate large amounts of lead (Pb), thereby causing a potential health risk by absorbing from polluted soils [8,19]. Considerable efforts have been reported to investigate Pb stress in roots, such as its accumulation, translocation, physiological and metabolic variations, and cell deposition [1,6,8,16]. Therefore, it is an important step towards being able to control the health risk in pollution condition by understanding the mechanism of Pb accumulation in plants roots.…”