title: Piriformospora indica confers cadmium tolerance in Nicotiana tabacum.
abstract: Piriformospora indica, a root-colonizing endophytic fungus of Sebacinales, promotes plant growth and confers resistance against biotic and abiotic stresses. In order to confirm the influence of P. indica on growth, proline, malondialdehyde (MDA), chlorophyll, and cadmium (Cd) amounts in Nicotiana tabacum under Cd stress, hydroponics, pot and field trials were conducted. The results showed that P. indica can store Cd in plant roots and reduce leaf Cd content, reduce the concentration of MDA, and increase the proline and chlorophyll content and the activities of catalase, peroxidase, and superoxide dismutase under hydroponic Cd stress. RT-PCR analysis showed that the relative expression level of genes Gsh2, TaPCS1, oas1, GPX, and Hsp70 in colonized plants was 4.3, 1.4, 2.9, 1.7, and 6.9 fold higher than in un-colonized plants respectively. Cd exposure significantly reduced un-colonized plants' agronomic traits compared to P. indica-colonized ones. Our results suggested that P. indica can sequester Cd in roots, so that much less cadmium was transported to leaves, and the increased concentrations of antioxidant enzymes, pigments and proline contents, as well as the higher expression of stress-related phytochelatin biosynthesis genes in P. indica-inoculated plants, may also serve to protect N. tabacum plants against oxidative damage, enhancing Cd tolerance.
authors.affiliation: Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; China Tobacco Guizhou Industrial Co., Ltd., Guiyang 550001, China. Electronic address: hfq543@126.com.
authors.forename: Feiqiong
authors.initials: F
authors.lastname: Hui
authors.affiliation: China Tobacco Guizhou Industrial Co., Ltd., Guiyang 550001, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Liu
authors.affiliation: Analysis Center of Agrobiology and Environmental Sciences, Zhejiang University, China.
authors.forename: Qikang
authors.initials: Q
authors.lastname: Gao
authors.affiliation: Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China. Electronic address: bglou@zju.edu.cn.
authors.forename: Binggan
authors.initials: B
authors.lastname: Lou
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects; D000975:Antioxidants / Q000378:metabolism; D001487:Basidiomycota / Q000502:physiology*; D002104:Cadmium / Q000378:metabolism / Q000633:toxicity*; D002734:Chlorophyll / Q000378:metabolism; D060026:Endophytes / Q000502:physiology; D015227:Lipid Peroxidation / Q000187:drug effects; D008315:Malondialdehyde / Q000378:metabolism; D054811:Phytochelatins / Q000096:biosynthesis; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development; D011392:Proline / Q000378:metabolism; D013312:Stress, Physiological / Q000187:drug effects; D014026:Nicotiana / Q000187:drug effects* / Q000378:metabolism / Q000382:microbiology* / Q000502:physiology; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D000975:Antioxidants; D002104:Cadmium; D002734:Chlorophyll; D008315:Malondialdehyde; D054811:Phytochelatins; D011392:Proline
keywords: Chlorophyll; Malondialdehyde; Plant endophytic fungus; Proline; Stress-related genes; Tobacco plants