Effects of Photoperiod and Vernalization on the Number of Leaves at Flowering in 32 Arabidopsis Thaliana (Brassicaceae) Ecotypes

Abstract

The extent of natural variation among wild type Arabidopsis thaliana L. Heynh for response to environmental stimuli that affect flowering is poorly documented. The effects of photoperiod and vernalization on the number of rosette leaves at the time of anthesis was measured for 32 Arabidopsis ecotypes. All ecotypes were vernalized 24 days at 4 C under continuous illumination. Vernalized and non vernalized plants were transplanted into 8-(short-day) and 20-hour (long-day) photoperiods In controlled environment growth chambers. Two ecotypes failed to flower after 110 days. Mean leaf number was less for all ecotypes under long day compared to short day. Sixteen ecotypes responded to vernalization; eight had reduced leaf number regardless of photoperiod, and eight had reduced leaf number only under short day. Two ecotypes required vernalization to flower in this study. For three ecotypes, vernalization and short day resulted in a reduction in leaf number whereas vernalization and long day resulted in increased leaf number. Documentation of the effects and interactions of photoperiod and vernalization across many ecotypes provides a broader range of described natural variation for genetic and physiologic study.

The effect of seed and rosette cold treatment on germination and flowering time in some Arabidopsis thaliana (Brassicaceae) ecotypes

“…This presumably explains the differences between our results and those of Karlsson, Sills, and Nienhuis (1993), who identified several ecotypes that did not respond to cold treatment, including two, LER and EDJ-O, that seemed to respond in our study. As can be seen from Table 1, all lines except TSU-O seem to respond to cold treatment under our conditions.…”

“…As can be seen from Table 1, all lines except TSU-O seem to respond to cold treatment under our conditions. TSU-0 stands out as being strikingly insensitive to cold treatment (this ecotype was also found insensitive by Karlsson, Sills, and Nienhuis [1993]). …”

Reduction of mineral nutrient availability accelerates flowering of Arabidopsis thaliana

“…Flowering time in A. thaliana is quantified either as the number of leaves (total or rosette) or as days to flowering (bud appearance, beginning of inflorescence shoot elongation or anthesis are used). There is usually a good correlation between days to flowering and leaf number (Koornneef et al, 1991;Karlsson et al, 1993). However, the total leaf number was not proportional to the time of bud appearance in our initial experiments.…”

“…Ecotype differences in flowering response to various factors have frequently been observed in A. thaliana, e.g. for vernalization (Karlsson et al, 1993) or light quality (Lee and Amasino, 1995). We employed three ecotypes: Ler, Col and Sf-2.…”

Arabidopsis Thaliana: From Weed to Model Organism

“…The most popular include Columbia (Col), Landsberg erecta (Laer), and Wassilewskija (Ws), with each ecotype named according to where it grows in the wild with some exceptions (Nordborg et al, 2005). Each ecotype developmental life cycle can vary widely (Karlsson, Sills, & Nienhuis, 1993;Nordborg & Bergelson, 1999). Since Col is considered the reference genome, as it was the first to be sequenced (The Arabidopsis Genome Initiative, 2000), most well-established protocols are drafted using this ecotype.…”