Grape Berry Splitting Is Correlated with Cell Wall Pectin Content and Cutin Composition.

Area of Science:

• Plant Physiology
• Horticultural Science
• Agricultural Chemistry

Background:

• Fruit splitting in horticulture leads to significant economic losses.
• The physiological basis of berry splitting in grapevine (Vitis vinifera L.) is not well understood.
• Understanding splitting mechanisms is crucial for improving table grape cultivation.

Purpose of the Study:

• To investigate the relationship between epidermal cell wall and cuticular traits and berry splitting susceptibility in grapevine cultivars.
• To identify key physiological and molecular factors determining resistance or susceptibility to splitting.
• To provide insights into potential strategies for reducing berry splitting.

Main Methods:

• Evaluated splitting susceptibility across six Vitis vinifera L. cultivars.
• Analyzed epidermal cell density and cuticle thickness.
• Quantified cell wall pectin content at ripeness.
• Utilized Gas Chromatography-Mass Spectrometry (GC-MS) for cutin monomer profiling.

Main Results:

• Splitting was not correlated with epidermal cell density or cuticle thickness.
• Resistant cultivars showed higher cell wall pectin content at ripeness.
• GC-MS revealed a shift from aliphatic to phenolic monomers during ripening.
• Higher accumulation of phenolic monomers (e.g., cinnamic acid-3,5-dimethoxy, methyl-3,4-dihydroxybenzoate) and fatty acids (C16:0, C18:0) in resistant cultivars was associated with reduced splitting.

Conclusions:

• Cell wall pectin content and cutin monomer composition are critical factors influencing grape berry splitting.
• Specific phenolic compounds and fatty acids in the cuticle play a role in mitigating splitting.
• These findings suggest potential molecular targets for breeding or treating table grape cultivars to reduce splitting.