PMID- 12081538
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20240109
IS  - 1399-3054 (Electronic)
IS  - 0031-9317 (Linking)
VI  - 115
IP  - 3
DP  - 2002 Jul
TI  - Far red end-of-day treatment restores wild type-like plant length in hybrid aspen 
      overexpressing phytochrome A.
PG  - 448-457
AB  - Shoot elongation in woody plants is modulated by a multitude of light signals, 
      including irradiance, photoperiod and spectral composition, for which the 
      phytochrome system is the probable photoreceptor. In hybrid aspen (Populus 
      tremula x tremuloides) overexpression of the oat phytochrome A (PHYA) prevents 
      growth cessation in response to short photoperiod, and plants exhibit dwarf 
      growth that is related to reduced cell numbers and reduced gibberellin contents. 
      End-of-day far-red treatment significantly enhances internode elongation in PHYA 
      overexpressors as well as in the wild type, and this was found here to be caused 
      by stimulation of cell division and cell extension. In PHYA overexpressors the 
      effects were substantially larger than in the wild type, and resulted in complete 
      restoration of wild type-like plant length as well as cell numbers, and 
      gibberellin content was greatly increased. No clear effect of far-red end-of-day 
      treatment on gibberellin levels could be detected in the wild type. It thus 
      appears that the far-red end-of-day treatment might modify the responsiveness of 
      the tissue to GA rather than the GA levels. The observed effects were completely 
      reversed by a subsequent irradiation with red light. The present data show that 
      dwarfism due to PHYA overexpression can be completely overcome by far red 
      end-of-day treatment, and the observations indicate that effects of far red 
      end-of-day treatments appear to be mediated by phytochrome(s) other than 
      phytochrome A.
FAU - Olsen, Jorunn E
AU  - Olsen JE
AD  - Department of Biology, University of Tromso, N 9037 Tromso, Norway Present 
      address: Department of Biology and Nature Conservation, Box 5014, Agricultural 
      University of Norway, N-1432 As, Norway.
FAU - Junttila, Olavi
AU  - Junttila O
LA  - eng
PT  - Journal Article
PL  - Denmark
TA  - Physiol Plant
JT  - Physiologia plantarum
JID - 1256322
EDAT- 2002/06/26 10:00
MHDA- 2002/06/26 10:01
CRDT- 2002/06/26 10:00
PHST- 2002/06/26 10:00 [pubmed]
PHST- 2002/06/26 10:01 [medline]
PHST- 2002/06/26 10:00 [entrez]
AID - ppl1150315 [pii]
AID - 10.1034/j.1399-3054.2002.1150315.x [doi]
PST - ppublish
SO  - Physiol Plant. 2002 Jul;115(3):448-457. doi: 10.1034/j.1399-3054.2002.1150315.x.