Postharvest storage affects the chemical composition of the avocado fruit cuticle in a cultivar-specific manner

The cuticle plays critical roles during fruit development, however there have been scarce research on how the cuticle regulates fruit quality and stress tolerance during storage. Here, we provide the first inclusive repertoire of cutin polymer composition of the avocado fruit cuticle via gas chromatography-mass spectrometry, revealing key aliphatic and phenolic monomers. Microscopy and metabolite profiling delineated natural variations in cuticle thickness and cutin loads of 'Ardit' and 'Hass' fruit cultivars. Postharvest storage assays suggested that cold temperatures and relative humidity affect the avocado fruit cutin compositions in a cultivar-specific manner. Ardit fruit maintained their cutin load and composition during storage, whereas reduced cutin loads were detected in Hass fruit that exhibited a unique ability to rewire their cuticle to a more phenolic profile. Our data may suggest that the thicker cuticles deposited by Ardit fruit provided a mean to cope better with injuries arise by pathogenic fungi during storage.