Biochelator Assisted Phytoremediation for Cadmium (Cd) Pollution in Paddy Field

Yangyang Wang,Ming Chang,Tongtong Li,Jianfeng Xu,Jinsheng Wang,Shaofeng Li,Ruyue Yang,Xiaoshu Wang,Lei Wang,Jia Zhu

doi:10.3390/su132112170

Abstract

To evaluate the efficacy of biochelators for phytoremediation of cadmium (Cd), effects of biochelators (humic acid, HA; polyaspartic acid, PASP; rhamnolipid, RLs) and synthetic chelator (sodium tripolyphosphate, STPP) on the growth, accumulation, and antioxidant index of Cd were investigated in Iris sibirica L. The results indicated that the addition of HA increased the dry weight of leaves and stems, and the addition of PASP, RLs, and STPP increased the growth of leaves but inhibited the growth of stems. The determination of Cd accumulation indicated that HA decreased the content of Cd in all tissues, while the addition of PASP, RLs, and STPP increased the accumulation of Cd in stems and roots. In addition, the determination of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities indicated that the treatment of PASP and RLs increased the activities of antioxidant enzymes, which might be beneficial to the resistance of Cd for Iris sibirica L. Overall, these results indicated that biochelators may improve the phytoremediation efficacy of Iris sibirica L. on Cd polluted paddy field. Among the tested chelators, PASP exhibited the best comprehensive efficacy and the highest commercial potential.

Highlights

Cadmium (Cd) is a highly toxic pollutant and is widely distributed in environments [1].Due to its strong mobility, Cd can enter water, soil, and paddy field, and accumulate in plants including crops
polyaspartic acid (PASP), RLs, and may be beneficial to the growth small (Figure 2). These results indicate that PASP, RLs, and sodium tripolyphosphate (STPP) may be beneficial to the of roots but damage the leaves, which is consistent with previous studies [16,17]
The application of humic acid (HA) significantly promoted the growth of Iris sibirica L. but reduced the accumulation of Cd in plants

Summary

Introduction

Cadmium (Cd) is a highly toxic pollutant and is widely distributed in environments [1]. Due to its strong mobility, Cd can enter water, soil, and paddy field, and accumulate in plants including crops. Scientists are actively seeking more economical methods to repair Cd-polluted areas. Adsorption and phytoremediation are commonly used methods to repair Cd-polluted in the environment. The method of adsorption is mainly to remove Cd2+ in the environment through the preparation of new adsorption functional materials (such as biochar [4], cellulose [5], etc.). The adsorbents are useful for the pollution of Cd, they are difficult to remove from the environment, which may cause new environmental problems

Methods

Results

Conclusion