title: Unraveling the role of dark septate endophyte (DSE) colonizing maize (Zea mays) under cadmium stress: physiological, cytological and genic aspects.
abstract: A growing body of evidence suggests that plant root-associated fungi such as dark septate endophytes (DSE) can help plants overcome many biotic and abiotic stresses, of great interest is DSE-plant metal tolerance and alleviation capabilities on contaminated soils. However, the tolerance and alleviation mechanisms involved have not yet been elucidated. In the current study, the regulation and physiological response of Zea mays to its root-associated DSE, Exophiala pisciphila was analyzed under increased soil Cd stress (0, 10, 50, 100 mg kg(-1)). Under Cd stress, DSE inoculation significantly enhanced the activities of antioxidant enzymes and low-molecular weight antioxidants, while also inducing increased Cd accumulation in the cell wall and conversion of Cd into inactive forms by shoot and root specific regulation of genes related to metal uptake, translocation and chelation. Our results showed that DSE colonization resulted in a marked tolerance to Cd, with a significant decrease in cadmium phytotoxicity and a significant increase in maize growth by triggering antioxidant systems, altering metal chemical forms into inactive Cd, and repartitioning subcellular Cd into the cell wall. These results provide comprehensive evidence for the mechanisms by which DSE colonization bioaugments Cd tolerance in maize at physiological, cytological and molecular levels.
authors.affiliation: State Key Laboratory of Conservation and Utilization for Bioresources in Yunnan, Yunnan University, Kunming, 650091 Yunnan, P.R. China.|Key Laboratory of Microbial Diversity in Southwest China, Ministry of Education, Yunnan University, Kunming, 650091 Yunnan, P.R. China.|First People's Hospital of Qujing City, Qujing Affiliated Hospital of Kunming Medical University, Qujing 655000, China.
authors.forename: Jun-ling
authors.initials: JL
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Conservation and Utilization for Bioresources in Yunnan, Yunnan University, Kunming, 650091 Yunnan, P.R. China.|Key Laboratory of Microbial Diversity in Southwest China, Ministry of Education, Yunnan University, Kunming, 650091 Yunnan, P.R. China.
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.affiliation: State Key Laboratory of Conservation and Utilization for Bioresources in Yunnan, Yunnan University, Kunming, 650091 Yunnan, P.R. China.|Key Laboratory of Microbial Diversity in Southwest China, Ministry of Education, Yunnan University, Kunming, 650091 Yunnan, P.R. China.
authors.forename: Gao-yuan
authors.initials: GY
authors.lastname: Liu
authors.affiliation: Irving K. Barber School of Arts and Sciences, University of British Columbia Okanagan, Kelowna, British Columbia V1V 1V7, Canada.
authors.forename: Joshua M
authors.initials: JM
authors.lastname: Smith
authors.affiliation: State Key Laboratory of Conservation and Utilization for Bioresources in Yunnan, Yunnan University, Kunming, 650091 Yunnan, P.R. China.|Key Laboratory of Microbial Diversity in Southwest China, Ministry of Education, Yunnan University, Kunming, 650091 Yunnan, P.R. China.
authors.forename: Zhi-wei
authors.initials: ZW
authors.lastname: Zhao
mesh_terms: D000220:Adaptation, Biological; D000975:Antioxidants / Q000378:metabolism; D001692:Biological Transport; D002104:Cadmium / Q000378:metabolism*; D060026:Endophytes; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D008658:Inactivation, Metabolic / Q000235:genetics; D042541:Intracellular Space / Q000378:metabolism; D010084:Oxidation-Reduction; D017382:Reactive Oxygen Species / Q000378:metabolism; D013312:Stress, Physiological; D003313:Zea mays / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology*
chemical_list: D000975:Antioxidants; D017382:Reactive Oxygen Species; D002104:Cadmium