Morphological Changes Associated with Bruising in Strawberry Fruit Surface and Internal Tissues

Abstract

Physical damage to strawberry fruit caused by bruising is a serious problem, and the underlying mechanisms remain poorly understood. In this study, the mechanism and location of bruising in strawberry fruit were investigated by confocal laser scanning microscopy. Observations of the three-dimensional and two-dimensional structure of the fruit surface and cross-sectional examination of the flesh and pith cells revealed that bruising is caused by external forces that induce flesh cell compression without affecting the skin surface and pith cell morphology. These results indicate that the skin that does not transmit external forces to internal tissues and the flesh cells that are not easily deformed are crucial for preventing bruising in strawberry fruit.