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Microbial Ecology

, Volume 49, Issue 3, pp 343–352 | Cite as

Aggregates of Resident Bacteria Facilitate Survival of Immigrant Bacteria on Leaf Surfaces

  • J.-M. Monier
  • S.E. LindowEmail author
Article

Abstract

The fate of immigrant bacterial cells on leaves under stressful conditions was determined as a function of the anatomical features and the local spatial density of resident cells at their landing site. Pantoea agglomerans 299R was established on bean leaves and the survival of immigrant cells of Pseudomonas fluorescens A506 and Pseudomonas syringae B728a, as well as P. agglomerans itself, was determined by epifluorescence microscopy following subsequent exposure of plants to desiccation stress. Resident and immigrant bacterial strains constitutively expressed the cyan and the green fluorescent protein, respectively, and the viability of individual cells was assessed directly on leaf surfaces following propidium iodide staining. Although only a small fraction of the immigrant cells landed on established bacterial aggregates, their fate was usually strongly influenced by the presence of indigenous bacteria at the site at which they landed. Immigrants of P. agglomerans 299R or P. fluorescens A506 that arrived as solitary cells had about double the probability of survival when landing on aggregates formed by P. agglomerans 299R than when landing on uncolonized areas of the leaf surface. In contrast, the survival of P. syringae B728a was similar irrespective of whether it landed on colonized or uncolonized parts of a leaf. The nature of plant anatomical features at which immigrant bacteria landed also strongly influenced the fate of immigrant bacteria. The fraction of immigrant cells of each species tested that landed on veins, glandular trichomes, or epidermal cells altered by P. agglomerans that died was always less than when they landed on normal epidermal cells or at the base of hooked trichomes. Depending on the process by which immigrants arrive at a leaf, only a small fraction of cells may be deposited on existing bacterial aggregates. Although uncolonized sites differed greatly in their ability to influence the survival of immigrant cells, the fate of an immigrant bacterium will depend on the nature of the leaf structure on which it is deposited, and apparently indirectly on the amount of nutrients and water available at that site to support the development of bacterial aggregates.

Keywords

Leaf Surface Landing Site Glandular Trichome Desiccation Stress Resident Cell 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

We thank Dr. Maria Brandl and Dr. William Miller from the United States Department of Agriculture in Albany for providing us with Pantoea agglomerans 299R (pWM1009). This study was supported by grant 99-35303-8633 from the US Department of Agriculture National Research Initiative and by grant DR-F603-86ER13518 from the Department of Energy, as well as support from Torrey Mesa Research Institute, Syngenta Research and Technology, San Diego, CA.

References

  1. 1.
    Beattie, GA, Lindow, SE 1995The secret life of foliar bacterial pathogens on leavesAnnu Rev Phytopathol3345172Google Scholar
  2. 2.
    Brandl, MT, Lindow, SE 1996Cloning and characterization of a locus encoding an indolepyruvate decarboxylase involved in indole-3-acetic acid synthesis in Erwinia herbicolaAppl Environ Microbiol6241214128Google Scholar
  3. 3.
    Brandl, MT, Lindow, SE 1997Environmental signals modulate the expression of an indole-3-acetic acid biosynthetic gene in Erwinia herbicolaMol Plant Microbe Interact10499505Google Scholar
  4. 4.
    Brandl, MT, Lindow, SE 1998Contribution of indole-3-acetic acid production to the epiphytic fitness of Erwinia herbicolaAppl Environ Microbiol6432563263Google Scholar
  5. 5.
    Brandl, MT, Quiñones, B, Lindow, SE 2001Heterogeneous transcription of an indoleacetic acid biosynthetic gene in Erwinia herbicola on plant surfacesProc Natl Acad Sci USA9834543459Google Scholar
  6. 6.
    Hallman, JA, Quadt-Hallmann, A, Miller, WG, Sikora, RA, Lindow, SE 2001Endophytic colonization of plants by the biological control agent Rhizobium etli G12 in relation to Meloidogyne incognita infectionPhytopathology91415422Google Scholar
  7. 7.
    Hirano, SS, Upper, CD 2000Bacteria in the leaf ecosystem with emphasis on Pseudomonas syringae — a pathogen, ice nucleus, and epiphyteMicrobiol Mol Biol Rev64624653Google Scholar
  8. 8.
    Johnson, KB 1994Dose–response relationships and inundative biological controlPhytopathology84780784Google Scholar
  9. 9.
    Joyner, DC, Lindow, SE 2000Heterogeneity of iron bioavailability on plants assessed with a whole-cell GFP-based bacterial biosensorMicrobiology14624352445Google Scholar
  10. 10.
    King, EO, Ward, MK, Raney, DE 1954Two simple media for the demonstration of pyocyanin and fluoresceinJ Lab Clin Med44301307Google Scholar
  11. 11.
    Kinkel, LL, Wilson, M, Lindow, SE 1996Utility of microcosm studies for predicting phylloplane bacterium population sizes in the fieldAppl Environ Microbiol6234133423Google Scholar
  12. 12.
    Leveau, JHJ, Lindow, SE 2001Appetite of an epiphyte: quantitative monitoring of bacterial sugar consumption in the phyllosphereProc Natl Acad Sci USA9834463453Google Scholar
  13. 13.
    Lindow, SE, Brandl, MT 2003Microbiology of the phyllosphereAppl Environ Microbiol6918751883Google Scholar
  14. 14.
    Loper, JE, Lindow, SE 1987Lack of evidence for in situ fluorescent pigment production by Pseudomonas syringae pv. syringae on bean leaf surfacesPhytopathology7714491454Google Scholar
  15. 15.
    Mercier, J, Lindow, SE 2000Role of leaf surface sugars in colonization of plants by bacterial epiphytesAppl Environ Microbiol66369374Google Scholar
  16. 16.
    Miller, WG, Bates, AH, Horn, ST, Brandl, MT, Wachtel, MR, Mandrell, RE 2000Detection on surfaces and in Caco-2 cells of Campylobacter jejuni cells transformed with new gfp, yfp, and cfp marker plasmidsAppl Environ Microbiol6654265436Google Scholar
  17. 17.
    Monier, J-M, Lindow, SE 2004Frequency, size and localization of bacterial aggregates on bean leaf surfacesAppl Environ Microbiol70346355Google Scholar
  18. 18.
    Monier, J-M, Lindow, SE 2003Pseudomonas syringae responds to the environment on leaves by cell size reductionPhytopathology9312091216Google Scholar
  19. 19.
    Monier, J-M, Lindow, SE 2003Differential survival of solitary and aggregated bacterial cells promotes aggregate formation on leaf surfacesProc Natl Acad Sci USA1001597715982Google Scholar
  20. 20.
    Monier, J-M, Lindow, SE (2004) Spatial organization of dual-species bacterial aggregates on leaf surfaces. Appl Environ Microbiol (in press)Google Scholar
  21. 21.
    Morris, CE, Barnes, MB, McLean, RJC 2002Biofilms on leaf surfaces: implications for the biology, ecology and management of populations of epiphytic bacteriaLindow, SEHecht-Poinar, EIElliot, VJ eds. Phyllosphere MicrobiologyAPS PressSt. Paul, MN138154Google Scholar
  22. 22.
    Morris, CE, Monier, J-M, Jacques, M-A 1997Methods for observing microbial biofilms directly on leaf surfaces and recovering them for isolation of culturable microorganismAppl Environ Microbiol6315701576Google Scholar
  23. 23.
    O’Brien, RD, Lindow, SE 1989Effect of plant species and environmental conditions on epiphytic population sizes of Pseudomonas syringae and other bacteriaPhytopathology79619627Google Scholar
  24. 24.
    Sambrook, J, Fritsch, EF, Maniatis, T 1989Molecular Cloning, a Laboratory ManualCold Spring Harbor Laboratory PressCold Spring Harbor, NYGoogle Scholar
  25. 25.
    Upper, CD, Hirano, SS, Dodd, KK, Clayton, MK 2003Factors that affect spread of Pseudomonas syringae in the phyllospherePhytopathology9310821092Google Scholar
  26. 26.
    Wilson, M, Lindow, SE 1993Effect of phenotypic plasticity on epiphytic survival and colonization by Pseudomonas syringaeAppl Environ Microbiol59410416Google Scholar
  27. 27.
    Wilson, M, Lindow, SE 1994Inoculum density–dependent mortality and colonization of the phyllosphere by Pseudomonas syringaeAppl Environ Microbiol6022322237Google Scholar
  28. 28.
    Wilson, M, Lindow, SE 1994Coexistence among epiphytic bacterial populations mediated through nutritional resource partitioningAppl Environ Microbiol6044684477Google Scholar

Copyright information

© Springer Science+Business Media, Inc. 2005

Authors and Affiliations

  1. 1.Department of Plant and Microbial BiologyUniversity of CaliforniaBerkeleyUSA

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