title: Colonization and modulation of host growth and metal uptake by endophytic bacteria of Sedum alfredii.
abstract: Sedum alfredii Hance is a Zn and Cd co-hyperaccumulating plant species found in an old mining area in China. Four bacterial strains, Burkholderia sp. SaZR4, Burkholderia sp. SaMR10, Sphingomonas sp. SaMR12 and Variovorax sp. SaNR1, isolated from surface-sterilized S. alfredii plants were used to investigate their endophytic nature and root colonization patterns and effects on phytoextraction of Zn and Cd. Laser scanning confocal microscopy revealed that gfp-tagged SaZR4, SaMR12, and SaNR1 cells formed biofilms on roots and that SaZR4 and SaMR12 cells could invade root tissues. SaMR10 showed the lowest total population associated with S. alfredii and little effect on plant growth and phytoextraction. SaZR4 significantly promoted Zn-extraction but not Cd-extraction. SaMR12 and SaNR1 significantly promoted plant growth in substrates supplemented with Zn or Cd and phytoextraction of Zn and Cd. Together, this study have shown that the four native endophytic bacteria differently colonize the host plants and modulate metal uptake and growth of host plant, and that SaMR12 and SaNR1 strains are promising assistants of S. alfredii plants for phytoremediation of Zn/Cd-contaminated soil.
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecosystem Health, College of Environmental and Resources Science, Zhejiang University, Zijingang Campus, Hangzhou, China.
authors.forename: Xincheng
authors.initials: X
authors.lastname: Zhang
authors.forename: Li
authors.initials: L
authors.lastname: Lin
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Zhu
authors.forename: Xiaoe
authors.initials: X
authors.lastname: Yang
authors.forename: Yuyan
authors.initials: Y
authors.lastname: Wang
authors.forename: Qianli
authors.initials: Q
authors.lastname: An
mesh_terms: D020562:Betaproteobacteria / Q000166:cytology / Q000502:physiology*; D001673:Biodegradation, Environmental; D018441:Biofilms; D018533:Biomass; D019117:Burkholderia / Q000166:cytology / Q000502:physiology*; D002104:Cadmium / Q000032:analysis / Q000378:metabolism*; D002681:China; D060026:Endophytes; D049452:Green Fluorescent Proteins; D049408:Luminescent Agents; D018613:Microscopy, Confocal; D018517:Plant Roots / Q000254:growth & development / Q000378:metabolism / Q000382:microbiology; D018520:Plant Shoots / Q000254:growth & development / Q000378:metabolism / Q000382:microbiology; D031963:Sedum / Q000166:cytology / Q000254:growth & development / Q000378:metabolism / Q000382:microbiology*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants; D020578:Sphingomonas / Q000166:cytology / Q000502:physiology*; D013559:Symbiosis; D015032:Zinc / Q000032:analysis / Q000378:metabolism*
chemical_list: D049408:Luminescent Agents; D012987:Soil; D012989:Soil Pollutants; D002104:Cadmium; D049452:Green Fluorescent Proteins; D015032:Zinc