Enhanced phytoremediation of atrazine-contaminated soil by vetiver (Chrysopogon zizanioides L.) and associated bacteria

• Published in: Environmental science and pollution research international 2023-03, Vol.30 (15), p.44415-44429
• Main Authors: Zhang, Faming, Sun, Shixian, Rong, Yuhong, Mao, Lili, Yang, Shuchun, Qian, Ling, Li, Rongbiao, Zheng, Yi
• Format: Article
• Language: English
• Subjects: Agricultural land; Agricultural pollution; Aquatic Pollution; Arthrobacter; Atmospheric Protection/Air Quality Control/Air Pollution; Atrazine; Atrazine - metabolism; Bacteria; Bacteria - metabolism; Biodegradation, Environmental; Chrysopogon; Chrysopogon zizanioides; Degradation; Dissipation factor; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental science; Farm buildings; Food chains; Food contamination; Grasses; Herbicides; Humans; Metabolites; Nontarget organisms; Phytoremediation; Research Article; Rhizosphere; Rhodococcus; Roots; Shoots; Soil; Soil contamination; Soil degradation; Soil Pollutants - analysis; Soil pollution; Soil remediation; Soil treatment; Soils; Waste Water Technology; Water Management; Water Pollution Control
• ISSN: 1614-7499; 0944-1344; 1614-7499
• DOI: 10.1007/s11356-023-25395-w

The intensive and long-term use of atrazine (ATZ) has led to the contamination of agricultural soils and non-target organisms, posing a series of threats to human health through the transmission of the food chain. In this study, a 60-day greenhouse pot experiment was carried out to explore the phytoremediation by Chrysopogon zizanioides L. (vetiver). The uptake, accumulation, distribution, and removal of ATZ were investigated, and the degradation mechanisms were elucidated. The results showed that the growth of vetiver was inhibited in the first 10 days of the incubation; subsequently, the plant recovered rapidly with time going. Vetiver grass was capable of taking up ATZ from the soil, with root concentration factor ranging from 2.36 to 15.55, and translocating to the shoots, with shoot concentration factor ranging from 7.51 to 17.52. The dissipation of ATZ in the rhizosphere soil (97.51%) was significantly higher than that in the vetiver-unplanted soil (85.14%) at day 60. Metabolites were identified as hydroxyatrazine (HA), deethylatrazine (DEA), deisopropylatrazine (DIA), and didealkylatrazine (DDA) in the samples of the shoots and roots of vetiver as well as the soils treated with ATZ. HA, DEA, DIA, and DDA were reported first time as metabolites of ATZ in shoots and roots of vetiver grown in soil. The presence of vetiver changed the formation and distribution of the dealkylated products in the rhizosphere soil, which remarkably enhanced the occurrence of DEA, DIA, and DDA. Arthrobacter , Bradyrhizobium , Nocardioides , and Rhodococcus were the major atrazine-degrading bacterial genera, which might be responsible for ATZ degradation in the rhizosphere soil. Our findings suggested that vetiver grass can significantly promote ATZ degradation in the soil, and it could be a strategy for remediation of the atrazine-contaminated agricultural soil. Graphical Abstract