, Volume 142, Issue 2, pp 187–193

The relationship between phytochrome-photoequilibrium and Development in light grown Chenopodium album L.

  • D. C. Morgan
  • H. Smith

DOI: 10.1007/BF00388211

Cite this article as:
Morgan, D.C. & Smith, H. Planta (1978) 142: 187. doi:10.1007/BF00388211


Chenopodium album seedlings were grown in light environments in which supplementary far-red light was mixed with white fluorescent light during various parts of the photoperiod. Both the logarithmic rate constant of stem extension and the leaf dry weight: stem dry weight ratio were linearly related to estimated phytochrome photoequilibrium (ϕ) in each treatment regime. These data are taken to be indicative of a functional link between phytochrome and development in the green plant. A layer of chlorophyllous tissue only affected the linearity between calculated ϕ and the logarithmic stem extension rate at high chlorophyll concentrations, whilst even low concentrations-equivalent to the levels found in stem tissue-caused a significant shift in measured ϕ. End-of-day supplementary far-red (FR) light induced between 0–35 per cent of the response elicited by all-day supplementary FR, whilst daytime supplementary FR (with a white fluorescent light end-of-day treatment) induced approximately 90 per cent. The ecological significance of this difference is discussed with respect to shade detection.

Key words

ChenopodiumFar-redPhotoequilibriumPhytochromeStem extension

Copyright information

© Springer-Verlag 1978

Authors and Affiliations

  • D. C. Morgan
    • 1
  • H. Smith
    • 1
  1. 1.Department of Physiology and Environmental StudiesUniversity of Nottingham, School of AgricultureSutton Bonington, LoughboroughUK