title: Raoultella sp. strain L03 fixes N2 in association with micropropagated sugarcane plants.
abstract: N2 -fixing bacteria belonging to the genus Raoultella of the family Enterobacteriaceae are widely associated with plants. Raoultella sp. strain L03 was isolated from surface-sterilized sugarcane roots. In this study, we inoculated the strain L03 to microbe-free micropropagated plantlets of the main sugarcane cultivar ROC22 grown in Guangxi, China and determined N2 -fixation and association between strain L03 and sugarcane plants. Inoculation of strain L03 increased plant biomass, total N, N concentration and chlorophyll, and relieved N-deficiency symptoms of plants under an N-limiting condition. An (15) N isotope dilution assay revealed (15) N isotope dilution in the inoculated sugarcane plants and incorporation of the fixed (14) N from air into chlorophyll. Moreover, a gfp-tagged and antibiotic-resistant L03 strain was reisolated from surface-sterilized sugarcane plants and was detected in plant tissues by fluorescent microscopy. This study for the first time demonstrates that a Raoultella bacterium is able to fix N2 in association with the plant host.
authors.affiliation: Sugarcane Research Center, Chinese Academy of Agricultural Sciences/Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences/Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture/Guangxi Key Laboratory of Sugarcane Genetic Improvement, Nanning, China.|College of Agriculture, Guangxi University/State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresource, Nanning, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Luo
authors.affiliation: College of Agriculture, Guangxi University/State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresource, Nanning, China.|Vegetable Research Institute of Nanning City, Nanning, China.
authors.forename: Xue-Qing
authors.initials: XQ
authors.lastname: Ou-Yang
authors.affiliation: Sugarcane Research Center, Chinese Academy of Agricultural Sciences/Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences/Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture/Guangxi Key Laboratory of Sugarcane Genetic Improvement, Nanning, China.|College of Agriculture, Guangxi University/State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresource, Nanning, China.
authors.forename: Li-Tao
authors.initials: LT
authors.lastname: Yang
authors.affiliation: Sugarcane Research Center, Chinese Academy of Agricultural Sciences/Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences/Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture/Guangxi Key Laboratory of Sugarcane Genetic Improvement, Nanning, China.|College of Agriculture, Guangxi University/State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresource, Nanning, China.
authors.forename: Yang-Rui
authors.initials: YR
authors.lastname: Li
authors.affiliation: College of Agriculture, Guangxi University/State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresource, Nanning, China.
authors.forename: Xiu-Peng
authors.initials: XP
authors.lastname: Song
authors.affiliation: Sugarcane Research Center, Chinese Academy of Agricultural Sciences/Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences/Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture/Guangxi Key Laboratory of Sugarcane Genetic Improvement, Nanning, China.
authors.forename: Ge-Min
authors.initials: GM
authors.lastname: Zhang
authors.affiliation: Sugarcane Research Center, Chinese Academy of Agricultural Sciences/Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences/Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture/Guangxi Key Laboratory of Sugarcane Genetic Improvement, Nanning, China.
authors.forename: Yi-Jing
authors.initials: YJ
authors.lastname: Gao
authors.affiliation: Sugarcane Research Center, Chinese Academy of Agricultural Sciences/Sugarcane Research Institute, Guangxi Academy of Agricultural Sciences/Key Laboratory of Sugarcane Biotechnology and Genetic Improvement (Guangxi), Ministry of Agriculture/Guangxi Key Laboratory of Sugarcane Genetic Improvement, Nanning, China.
authors.forename: Wei-Xing
authors.initials: WX
authors.lastname: Duan
authors.affiliation: Institute of Biotechnology, Zhejiang University, Hangzhou, China.
authors.forename: Qianli
authors.initials: Q
authors.lastname: An
mesh_terms: D018533:Biomass; D060026:Endophytes / Q000302:isolation & purification / Q000378:metabolism*; D004755:Enterobacteriaceae / Q000302:isolation & purification / Q000378:metabolism*; D009586:Nitrogen Fixation / Q000502:physiology*; D018517:Plant Roots / Q000382:microbiology; D031786:Saccharum / Q000254:growth & development* / Q000378:metabolism* / Q000382:microbiology; D013559:Symbiosis
keywords: Endophytic bacteria; Nitrogen fixation; Plant growth-promoting bacteria; Raoultella; Sugarcane