Optimization of the irrigation schedule in field-grown strawberry results in higher water use efficiency and improved taste quality

Open field strawberry in Belgium is always drip irrigated. Most field-grown June bearing cultivar is Elsanta (Fragaria × ananassa ElsantaRSQUO). Irrigation is a necessity to achieve a consistent production. Often field-grown strawberry is cultivated under plastic rain shelter to protect the strawberry fruit from rain impact. Also temperature is higher under the rain shelter, which speeds up the growing cycle and results in an early strawberry yield, at the beginning of June. Common practice among strawberry growers is to maintain the root zone humid, with soil matrix potential (Ψ_soil) close to 
-10 kPa. A tempered water uptake could result in a higher concentration of sugars and improved taste quality. To test this hypothesis, an experiment was set up in 2017 where conventional irrigation was compared with a deficit irrigation (DI) regime. Marketable yield in both treatments was equal, although Ψ_soil decreased to -70 kPa in the DI treatment. Predawn plant water potential (Ψ_plant) was lower in the DI treatment, which indicated moderate water deficit stress. This was reflected in taste quality parameters. Fruit in the DI treatment had higher concentrations of total soluble solids, sugars and acids. Also fruit aroma was significant affected by irrigation. Although overall variability in fruit quality over the experiment was high, this is an additional motivation for strawberry growers to cultivate June bearing field-grown strawberry under plastic rain shelter at a dryer irrigation regime.