Planta

, Volume 210, Issue 3, pp 497–501

Temperature-dependent internode elongation in vegetative plants of Arabidopsis thaliana lacking phytochrome B and cryptochrome 1

  • María Agustina Mazzella
  • Daniel Bertero
  • Jorge José Casal
Article

DOI: 10.1007/PL00008157

Cite this article as:
Mazzella, M., Bertero, D. & Casal, J. Planta (2000) 210: 497. doi:10.1007/PL00008157

Abstract.

 Vegetative plants of Arabidopsis thaliana (L.) Heynh. form a compact rosette of leaves in which internode growth is virtually arrested. Rapid extension of the internodes occurs after flower buds are present in the reproductive apex. Under natural radiation, continuous light from fluorescent lamps, or short photoperiods of light from fluorescent lamps, plants of the phyB cry1 double mutant (lacking both phytochrome B and cryptochrome 1) did not form normal rosettes because all the internodes showed some degree of elongation. Internode elongation was weak in the phyB single mutant and absent in the cry1 mutant, indicating redundancy between phytochrome B and cryptochrome 1. The absence of phytochrome A caused no effects. The failure to form normal rosettes was conditional because internode elongation was arrested at low temperatures in all the mutant combinations. In contrast, the temperature dependence of phytochrome B and cryptochrome 1 effects on hypocotyl growth was weak. The elongation of the internodes in phyB cry1 was not accompanied by early flowering as showed by the lack of effects on the final number of leaves. Apex dissection indicated that in phyB cry1 double mutants internode elongation anticipated the transition from the vegetative to the reproductive stage. Thus, stem growth in Arabidopsis thaliana is not fully dependent on the program of reproductive development.

Key words: Arabidopsis– Cryptochrome – Phytochrome – Stem growth – Vegetative development

Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • María Agustina Mazzella
    • 1
  • Daniel Bertero
    • 1
  • Jorge José Casal
    • 1
  1. 1.IFEVA, Departamento de Ecología, Facultad de Agronomía, Universidad de Buenos Aires, Av. San Martín 4453, 1417 Buenos Aires, ArgentinaAR