Skip to main content

Some NLM-NCBI services and products are experiencing heavy traffic, which may affect performance and availability. We apologize for the inconvenience and appreciate your patience. For assistance, please contact our Help Desk at info@ncbi.nlm.nih.gov.

Applied and Environmental Microbiology logoLink to Applied and Environmental Microbiology
. 1995 Mar;61(3):899–906. doi: 10.1128/aem.61.3.899-906.1995

Population Sizes, Immigration, and Growth of Epiphytic Bacteria on Leaves of Different Ages and Positions of Field-Grown Endive (Cichorium endivia var. latifolia)

M Jacques, L L Kinkel, C E Morris
PMCID: PMC1388372  PMID: 16534973

Abstract

Total, fluorescent, and pectolytic epiphytic bacterial population sizes were quantified on leaves of different age groups of broad-leaved endive during field cultivation from leaf emergence until harvest. Greater bacterial population densities (log(inf10) CFU per square centimeter) were observed on outer leaves than on inner leaves of the plants throughout the growing season. These differences were statistically significant for total bacterial populations at all sampling times and were often significant for fluorescent and pectolytic bacterial populations. At harvest, a linear gradient of decreasing densities of epiphytic bacteria from outer (older) to inner (younger) leaves of the head was significant. Leaf age influenced the frequency distribution and variability of bacterial population sizes associated with leaves of broad-leaved endive. Total bacterial population sizes were greater at leaf emergence for leaves emerging during the second half of the cultivation period than for leaves emerging earlier. The size of fluorescent and pectolytic bacterial populations on newly emerged leaves increased throughout the season as plants aged. To assess the importance of plant age on bacterial immigration at leaf emergence, bacterial densities were quantified on leaves emerging simultaneously on plants of different ages. In two of the three experiments, greater bacterial population sizes were observed on leaves emerging on younger plants. This indicates that factors other than an increase in concentration of airborne bacteria can lead to increases in population sizes at leaf emergence as plants age in the field. Results of leaf pruning experiments suggested that adjacent leaves may act as a barrier for immigration of fluorescent bacteria on newly emerged leaves. Survival of an inoculated strain of Pseudomonas fluorescens on newly emerged leaves generally did not vary with the age of plants. However, these effects were not consistent among experiments, suggesting that interactions among micro- and macroenvironmental conditions, physiological condition of leaves, and accessibility of leaves to airborne bacteria are important in controlling epiphytic bacterial population sizes.

Full Text

The Full Text of this article is available as a PDF (357.0 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Andrews J. H., Kenerley C. M. The effects of a pesticide program on non-target epiphytic microbial populations of apple leaves. Can J Microbiol. 1978 Sep;24(9):1058–1072. doi: 10.1139/m78-175. [DOI] [PubMed] [Google Scholar]
  2. Ercolani G. L. Bacteriological quality assessment of fresh marketed lettuce and fennel. Appl Environ Microbiol. 1976 Jun;31(6):847–852. doi: 10.1128/aem.31.6.847-852.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Geeson J. D. The fungal and bacterial flora of stored white cabbage. J Appl Bacteriol. 1979 Feb;46(1):189–193. doi: 10.1111/j.1365-2672.1979.tb02599.x. [DOI] [PubMed] [Google Scholar]
  4. Hirano S. S., Upper C. D. Diel Variation in Population Size and Ice Nucleation Activity of Pseudomonas syringae on Snap Bean Leaflets. Appl Environ Microbiol. 1989 Mar;55(3):623–630. doi: 10.1128/aem.55.3.623-630.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Hirano S. S., Upper C. D. Dynamics, spread, and persistence of a single genotype of Pseudomonas syringae relative to those of its conspecifics on populations of snap bean leaflets. Appl Environ Microbiol. 1993 Apr;59(4):1082–1091. doi: 10.1128/aem.59.4.1082-1091.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. KING E. O., WARD M. K., RANEY D. E. Two simple media for the demonstration of pyocyanin and fluorescin. J Lab Clin Med. 1954 Aug;44(2):301–307. [PubMed] [Google Scholar]
  7. Lindemann J., Constantinidou H. A., Barchet W. R., Upper C. D. Plants as sources of airborne bacteria, including ice nucleation-active bacteria. Appl Environ Microbiol. 1982 Nov;44(5):1059–1063. doi: 10.1128/aem.44.5.1059-1063.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. PATON A. M. An improved method for preparing pectate gels. Nature. 1959 Jun 27;183:1812–1813. doi: 10.1038/1831812b0. [DOI] [PubMed] [Google Scholar]

Articles from Applied and Environmental Microbiology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES