Effect of water deficit irrigation and inoculation with Botrytis cinerea on strawberry (Fragaria x ananassa) fruit quality

Deficit irrigation (DI) detrimentally affected berry size but had a profound effect on fruit physiology and biochemistry. Strawberry cv. Elsanta fruit from DI-treated plants had higher levels of abscisic acid (ABA). Dry matter content as a proportion of fresh weight was increased by a quarter in fruit from water-stressed plants as compared to fruit harvested from plants held at or near field capacity. Concomitant to this, the concentration of some taste-related (viz. monosaccharides and sugar/acid ratios) and health-related compounds/parameters (viz. antioxidant capacity and total phenolics) were generally much greater in DI-treated fruit. The effect of inoculation with Botrytis cinerea on fruit quality was also tested. Fruit derived from inoculated plants displayed symptoms of gray mold postharvest disease earlier than noninoculated fruit and had double the concentration of ABA. Inoculation had no significant effects on all other target analytes measured. There was no interaction between water treatment and inoculation. The possible mechanisms for increased synthesis of ABA and the different effects of pathogen-induced stress versus drought stress on fruit quality are discussed.