Biostimulator and biodegradable chelator to pytoextract stubborn soil Pb and Ni

Pb and Ni generally are stable associated with soil and sediment matrix rendering less phytoextraction efficiency. Sunflowers are selected for phytoremediation in this study. By integrating a plant growth hormone, GA3, as well as environmentally friendly and bio-degradable chelating agent, EDDS, this study aims to improve the effectiveness of the heavy metal contamination remediation via phytoremediation, thereby achieving environmental sustainability. The height and weight of the plants grown in the soil at a concentration level of Pb two times higher than regulatory standards performed worse than those at a concentration level one times higher than regulatory standards. The result indicates that the higher the Pb concentration level of the soil, the stronger the impact of toxicity to plant growth will be. The group with EDDS+GA3 is more suitable to be applied to the phytoremediation of soil at a concentration level of Ni two times higher than regulatory standards. DGGE analysis is conducted by using gradient screening after enlarging and purifying DNA sections. When a band appears, it indicates the dominant bacteria group. As a result, the more bands in a sample, the richer bacterial flora in the sample, and the higher possibility of diverse microorganisms. Intergrated phytoremediation has been proposed in this study.109