| Abstract Detail
Environmental Physiology Villegas, Daniel [1], Alcalde, Jose A. [2]. Timing of Photoperiod Sensitivity for Time to Flowering in Arabidopsis thaliana Landsberg erecta as Revealed by Reciprocal Transfer Experiments - what genetic control models should be able to explain. In most annual and biennial plants time to flowering is regulated by genetically controlled responses to environmental factors, mainly photoperiod (P) and temperature (T). Some photoperiod-sensitive plants are induced by a single inductive day/night cycle (e.g. Pharbitis nil, Sinapis alba), and others have a long photoperiod-sensitive phase, requiring several photoperiodic cycles to become induced. By reciprocally transferring plants grown in long days (LD) to short days (SD) and vice versa at different times after sowing, the durations of P-sensitive and P-insensitive phases of preflowering development can be estimated. An analytical procedure devised by Ellis et al. [Ann. Bot. 70: 87-92, 1992] for soybean and other annual plants was used to analyze the durations from sowing to flowering of reciprocally transferred Arabidopsis thaliana Landsberg erecta plants, in order to estimate the durations of these subphases. Results indicated that: a) Plants grown under 10 h d-1 photoperiod (SD) flowered 24.1 days later than plants grown under 20 h d-1, at a mean 20.0 °C temperature (range 16.9 to 23.3 °C). b) A photoperiod-sensitive phase for time to flowering was detected, starting approximately at 2.6 days after sowing and lasting for 20.7 days under LD or 44.8 days under SD. c) Plants transferred from LD to SD and vice versa at different times during this sensitive phase modified their flowering times gradually, implying a quantitative modulation of time to flowering by photoperiod. d) A post sensitive phase lasting 3.1 days accounted for the remaining time to flower. This behavior is similar to that of other species previously evaluated in which differences in flowering time are explained by differences in the duration of the photoperiod sensitive phase. Log in to add this item to your schedule
1 - Pontificia Universidad Catolica de Chile, Facultad de Agronomia e Ingenieria Forestal 2 - Pontificia Universidad Catolica de Chile, Facultad de Agronomia e Ingenieria Forestal, Casilla 306 - 22, Santiago, 6904411, Chile
Keywords: photoperiod sensitivity Arabidopsis reciprocal transfers.
Presentation Type: Plant Biology Abstract Session: P Location: Exhibit Hall (Northeast, Southwest & Southeast)/Hilton Date: Sunday, July 8th, 2007 Time: 8:00 AM Number: P01046 Abstract ID:2079 |