Light-stimulated cell expansion in bean (Phaseolus vulgaris L.) leaves. II. Quantity and quality of light required

Planta. 1990 Aug;182(1):77-80. doi: 10.1007/BF00239987.

Abstract

The quantity and quality of light required for light-stimulated cell expansion in leaves of Phaseolus vulgaris L. have been determined. Seedlings were grown in dim red light (RL; 4 micromoles photons m-2 s-1) until cell division in the primary leaves was completed, then excised discs were incubated in 10 mM sucrose plus 10 mM KCl in a variety of light treatments. The growth response of discs exposed to continuous white light (WL) for 16 h was saturated at 100 micromoles m-2 s-1, and did not show reciprocity. Extensive, but not continuous, illumination was needed for maximal growth. The wavelength dependence of disc expansion was determined from fluence-response curves obtained from 380 to 730 nm provided by the Okazaki Large Spectrograph. Blue (BL; 460 nm) and red light (RL; 660 nm) were most effective in promoting leaf cell growth, both in photosynthetically active and inhibited leaf discs. Far-red light (FR; 730 nm) reduced the effectiveness of RL, but not BL, indicating that phytochrome and a separate blue-light receptor mediate expansion of leaf cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Division / physiology
  • Cell Division / radiation effects
  • Culture Media
  • Culture Techniques
  • Fabaceae / cytology
  • Fabaceae / growth & development*
  • Fabaceae / radiation effects
  • Light*
  • Photons
  • Photoperiod*
  • Phytochrome / radiation effects
  • Plant Leaves / cytology*
  • Plant Leaves / growth & development*
  • Plant Leaves / radiation effects
  • Plants, Medicinal*
  • Potassium Chloride
  • Sucrose

Substances

  • Culture Media
  • Phytochrome
  • Sucrose
  • Potassium Chloride