The Effect of Deficit Irrigation on the Flowering Behaviour of Two Day-Neutral and One Everbearing Strawberry Cultivar

To determine the effect of deficit irrigation on the flowering behaviour of day-neutral and everbearing strawberries, three cultivars ('Albion', 'Evie 2' and 'Portola') were exposed to one of three irrigation regimes; 100% (control), 80% (mild stress), 60% (severe stress) evapotranspiration (ETp) for a period of five weeks. The plants were then allowed to reach maximum water capacity before drought stress treatments were repeated for a further five-week period. Irrigation was adjusted daily in accordance with changes in potential evapotranspiration; calibration coefficients were determined weekly by changes in weight of the pots over a 24-hour period. The number of flowers and berries produced was recorded twice weekly and results are presented for flower numbers over a 12-week period. Application of either the mild or severe deficit treatments did not advance flowering in any of the cultivars tested. A mild stress had no effect on the flower numbers but the severe stress caused a reduction in number up to eight weeks after the deficit treatments. However following the recovery period there was no effect on flower quantity.