Temperature signals contribute to the timing of photoperiodic
growth cessation and bud set in poplar
Bud set, the cornerstone delimiting the seasonal growth period in trees, is the dynamic net result of the often photoperiodcontrolled
growth cessation and the subsequent bud formation. Here, we show that in hybrid poplar, the critical day length
for growth cessation and the duration of bud formation each vary with local climatic conditions in identical genotypes. The
detailed dissection of bud set suggests temperature as one additional environmental factor that modifies the sensitivity to
day-length signals at growth cessation and influences the duration of bud formation in poplar. The ability of perennial plants
to integrate additional environmental signals with photoperiod signaling may add to short-term acclimatization to the predicted
longer growing seasons in future climates.