Winter manipulation of photoperiod and chill to enhance the perpetual flowering nature of 'Soprano'
In central Europe traditional cold-storage (3 months at -1.5°C) after digging leads to excessive runner development, high peaks and dips in production and finally sub-optimal yields. There exists an opportunity to raise tray-plants in glasshouses during the winter to address these shortcomings; however, the photoperiod and chill requirement conducive to everbearer development is poorly understood. We suspect an optimum set of conditions exists along a continuum whereby the vigour and generative behaviour of each cultivar is in balance. This trial aims to elucidate this relationship, specifically regarding photoperiod and chill. Plants were initially exposed to four different chill regimes, either in cold-storage (at -1.5°C) for 3 or 6 weeks, or in the glasshouse with a minimum temperature of +12 or +6°C. After chill had been acquired, plants were exposed to one of three photoperiods (natural winter day length 8-10, 12 or 16 h d‑1) at +12°C until planting. Total yield, fruit and stolon number and fruit quality assessments were subsequently carried out. We conclude that winter conditions can be manipulated to establish a more desirable plant type, improve resulting fruit quality and help to optimise the perpetual flowering behaviour of everbearers.
Gallace, N. and Lieten, P. (2021). Winter manipulation of photoperiod and chill to enhance the perpetual flowering nature of 'Soprano'. Acta Hortic. 1309, 333-340
Fragaria × ananassa, stolon, day length, phyllody, green tips, everbearer