Biochar and Bacillus sp. MN54 Assisted Phytoremediation of Diesel and Plant Growth Promotion of Maize in Hydrocarbons Contaminated Soil

Muhammad Hayder Ali,Muhammad Imran Khan,Fizza Mehmood,Muhammad Naveed,Rashad Qadri,Jawaher Alkahtani,Muhammad Aqeel Shoukat,Yheni Dwiningsih,Muhammad Azam,Mohamed S Elshikh,Saqib Bashir,Safdar Bashir,Yunzhou Li

doi:10.3390/agronomy11091795

Abstract

Contamination by petroleum hydrocarbons (PHs) is a great threat to environment due to the higher persistence and bio-toxicity of PHs. Therefore, removal of PHs from contaminated environment and strategies to reduce their toxic effects on living organisms are crucial for environmental safety and human health. The toxic effects of PHs from the polluted soil can be reduced by the addition of microbes and biochar. In this study, a pot trial was carried out to evaluate the effects of sugarcane bagasse (SB) biochar and Bacillus sp. MN54 addition on phytoremediation of PHs and growth of maize (Zea mays L.) in soil artificially contaminated with diesel. Maize seeds were sown in uncontaminated or contaminated (with PHs) soil, treated with biochar and Bacillus sp. MN54. The results revealed that PHs showed significant phytotoxicity to maize plants and the application of strain MN54 and biochar greatly reduced the toxic effects of PHs on plants growth and physiology by increasing the nutrients uptake in PHs contaminated soil. Interestingly, the phytotoxicity of PHs on maize plants was further reduced in the co-supplementation of strain MN54 and biochar. Plants physiological (25–48%) and agronomic (38–47%) attributes were significantly higher as compared to only PHs contaminated soil in the co-supplementation of strain MN54 and biochar. Similarly, nitrogen (41%), phosphorus (43%) and potassium (37%) concentrations were also increased in the co-supplementation of strain MN54 and biochar. Furthermore, maize plants successfully phytoremediate a considerable amount of PHs from soil particularly in the presence of strain MN54 and biochar, and this PHs removal was further enhanced in the co-supplementation of strain MN54 and biochar (i.e., 46% and 77% of initial PHs were removed in unplanted and planted treatments, respectively). The present results indicate that co-supplementation of biochar and Bacillus sp. MN54 could be effective in enhancing the degradation of PHs and improving plant growth in the hydrocarbons contaminated soil.

Highlights

Contamination by petroleum hydrocarbons (PHs) has become one of the most important environmental issues in the world [1]
The results showed that the toxicity of PHs caused significant reduction i.e., 56%, 51% and 42% in N, P and K contents of maize plant, respectively as compared to control
The results showed that the PHs removal in the planted soil was 25% higher besides of unplanted soil (Figure 2)

Summary

Introduction

Contamination by petroleum hydrocarbons (PHs) has become one of the most important environmental issues in the world [1]. Different anthropogenic activities such as improper management of underground storage tanks, transportation, industrial processes, accidental spills and mishandling of petroleum products have increased the PHs contamination in the environment [2,3]. Some of PHs are known to cause genotoxicity, reproductive toxicity, immuno-toxicity and carcinogenicity in animals and human beings [9,10]. The removal of PHs from the contaminated environment is crucial for the safety of ecosystem and human health [11]

Methods

Discussion

Conclusion