Citric Acid Assisted Phytoremediation of Chromium through Sunflower Plants Irrigated with Tannery Wastewater.

Ali Imran Mallhi,Muhammad Rizwan,Elsayed Fathi Abd_Allah,Mohammed Nasser Alyemeni,Shafaqat Ali,Abeer Hashem,Syed Asad Hussain Bukhar,Parvaiz Ahmad,Afzal Hussain,Shahzad Ali Shahid Chatha,Abdullah Ijaz Hussain,Zahid Imran Mallhi

doi:10.3390/plants9030380

Abstract

Heavy metals are rapidly polluting the environment as a result of growing industrialization and urbanization. The presence of high concentrations of chromium (Cr), along with other pollutants, is widespread in tannery wastewater. In Pakistan, as a result of a severe shortage of irrigation water, farmers use tannery wastewater to grow various crops with a consequent decline in plants’ yield. This experiment was performed to assess growth revival in sunflower plants irrigated with 0%, 25%, 50%, 75%, and 100% tannery wastewater, by foliar application of 0, 2.5, and 5.0 mM citric acid (CA). The wastewater treatment curtailed biomass accumulation, the growth rate, and chlorophyll contents by exacerbating the oxidative stress in sunflowers. Foliar application of CA considerably alleviated the outcomes of Cr toxicity by curbing the Cr absorption and oxidative damage, leading to improvements in plant growth, biological yield, and chlorophyll contents. It is concluded that foliar application of CA can successfully mitigate the Cr toxicity in sunflower plants irrigated with tannery wastewater.

Highlights

Kasur, a city in Punjab Pakistan, is famous for tanneries
Findings revealed that increasing concentration of wastewater treatment progressively reduced the plant height, root length, number of leaves per plant, and the leaf area (Figure 1), along with the fresh and dry weight of root, shoot, and leaves of sunflower (Figure 2)
Various morphological parameters of sunflowers, such as biomass, leaf area, number of leaves per plant, root length, and plant height considerably decreased with an increasing wastewater concentration (Figures 1 and 2), which may be attributed to the noxious amount of Cr in wastewater [20]

Summary

Introduction

A city in Punjab Pakistan, is famous for tanneries. According to estimates, around 144,502 to215,036 gallons of wastewater day−1 is discharged into the environment by 650 registered tanneries [1].Plants 2020, 9, 380; doi:10.3390/plants9030380 www.mdpi.com/journal/plantsTannery wastewater contains several organic and inorganic pollutants [2].

Results

Discussion

Conclusion