Oecologia

, Volume 68, Issue 2, pp 279–284

Comparative water use and nitrogen relationships in a mistletoe and its host

  • James R. Ehleringer
  • Craig S. Cook
  • Larry L. Tieszen
Original Papers

DOI: 10.1007/BF00384800

Cite this article as:
Ehleringer, J.R., Cook, C.S. & Tieszen, L.L. Oecologia (1986) 68: 279. doi:10.1007/BF00384800

Summary

The impact of the xylem-tapping mistletoe Phoradendron juniperinum on the nitrogen and water relations of its host Juniperus osteosperma was investigated under natural field conditions. Leaf conductance, leaf water potential, and leaf Kjeldahl nitrogen contents were followed through the growing season on mistletoes, infected junipers (separating infected from uninfected stems) and uninfected junipers. Infected trees experienced lower leaf water potentials than uninfected trees and also had lower leaf conductances and lower leaf nitrogen contents. Infected juniper stems had higher conductances than uninfected stems. Mistletoes had higher leaf nitrogen contents than their hosts and much of this nitrogen appeared as arginine, a potential nitrogen storage compound. Photosynthetic rates (per unit leaf area) were significantly higher in junipers than in the mistletoe, and higher in the uninfected than infected junipers. Water use efficiencies as estimated by carbon isotope ratios were significantly lower in mistletoes than in their hosts. Increased mistletoe infestation appeared to increase absolute water use efficiency of both host and mistletoe.

Copyright information

© Springer-Verlag 1986

Authors and Affiliations

  • James R. Ehleringer
    • 1
  • Craig S. Cook
    • 1
  • Larry L. Tieszen
    • 2
  1. 1.Department of BiologyUniversity of UtahSalt Lake CityUSA
  2. 2.Department of BiologyAugustana CollegeSioux FallsUSA