Scientific publications

Among environmental factors, photoperiod or light plays a decisive role in the timing of flowering in plants – one of the main adaptively significant traits. The effect of altered light conditions on the dynamics of transcriptional activity of the LFY gene, which plays a leading role in the initiation of plant flowering, was studied in laboratory settings. LFY expression was assessed in Arabidopsis thaliana from a northern natural population (Karelia). Plants of different ages (from 5 to 35 days) were tested in two groups: one group was grown under a natural long-day photoperiod (16L : 8D), and the other one was exposed to an artificial light regime, when light was provided at an unusual (night) time (8D : 16L). The dynamics of LFY expression were similar in the two groups: the level of transcriptional activity of the gene increased with plant age. However, under artificial light conditions, the transcriptional activity of LFY was higher in almost all age groups. Testing of flowering onset in plants under the altered light regime versus the natural conditions showed that such a change in the light regime leads to an increase in the proportion of early-flowering plants. It was thus concluded that light provision at unusual (nighttime) hours promoted the expression of the LFY gene. It was found that such a light schedule, while maintaining a long-day photoperiod, shifts the onset of flowering in plants to earlier timing. The LFY overexpression and earlier flowering are supposed to be evidence of an adaptive response to the altered light conditions.