Impacts of Deficit Irrigation on Strawberry Physiology, Water Productivity, Quality, and Yield

Strawberry (Fragaria × ananassa Duch.) has a unique flavor and nutritional value. To investigate the effects of deficit irrigation on the growth, yield, quality, and water use efficiency of strawberries, “Zhangji” and “Hongyan” varieties were assessed in a greenhouse. Four irrigation levels were set as 95% (CK), 75% (LS), 55% (MS), and 35% (±5%) (SS) of the field capacity, respectively. Five successive plant growth stages were analyzed. The results indicate that the plants’ daily water consumption intensity, as well as fruit yield and titratable acidity, decreased with increasing water stress, while vitamin C (Vc), soluble sugar, soluble protein, the sugar–acid ratio, and water use efficiency increased. Yield significantly decreased under the MS and SS treatments compared with CK. Malondialdehyde, proline contents, and superoxide dismutase activity reached the highest values under SS. Our results indicate that the greatest effect of water restriction occurs during the seedling growth and fruit color-turning periods. Given the higher Vc, titratable acidity, soluble sugars, and soluble proteins, the “Zhangji” variety may be preferable to the “Hongyan” variety, and an irrigation level at 70~80% of field capacity is recommended for good strawberry yield and taste quality. Deficit irrigation can save water resources, improve water use efficiency, and promote agricultural sustainable development.