1995 Volume 57 Issue 2 Pages 43-50
The effect of difference (DIF) between day temperature (DT) and night temperature (NT) and photoperiod on stem elongation of Verbena bonariensis L. plant was investigated. The combination of treatments was -10, 0 and +10 DIF and photoperiod of 8, 12 and 16 hours. Stem elongation was measured and analyzed with a non-contact method by a computer vision based system. Daily elongation markedly increased as DIF increased in all photoperiod treatments of 8, 12 and 16 hours. Longer photoperiod enhanced daily elongation at positive DIF (DT>NT) and zero DIF (DT=NT). DIF significantly affected elongation during the light period (EL) comparing to that during the dark period (ED). The magnitude of EL increased with increasing DIF and photoperiod.
