Fruit Maturity and Variety Shape Postharvest Diseases in Avocados

Harvest maturity strongly influences postharvest performance

The quality and storage performance of avocados after harvest are closely linked to fruit maturity and cultivar. A new study evaluated ten California avocado varieties to determine how these factors influence fungal diseases and physiological disorders during postharvest storage.

Researchers examined commercial and experimental cultivars, including 'Hass', 'GEM', 'Luna UCR', 'Eugenin' and 'Flavia', while monitoring dry matter accumulation, stem-end rot, body rot and vascular streaking throughout the season.

Seven fungal pathogens were identified

Using morphological and molecular analyses, the researchers identified seven fungal species associated with postharvest avocado decay.

These included four Neofusicoccum species (N. australe, N. luteum, N. nonquaesitum and N. parvum), Colletotrichum perseae, and two Diaporthe species (D. baccae and D. foeniculina).

Pathogenicity tests showed that Neofusicoccum nonquaesitum was the most aggressive pathogen, followed by Colletotrichum perseae and Diaporthe foeniculina, highlighting the complexity of managing stem-end and body rots in avocado fruit.

Dry matter content helps predict disease risk

One of the study's key findings is the relationship between fruit dry matter content and postharvest disease severity.

Researchers found that monitoring seasonal dry matter accumulation can improve harvest timing decisions and reduce susceptibility to certain fungal disorders in specific avocado varieties.

The authors suggest that respecting both minimum and potential maximum maturity standards before harvest may help minimise postharvest diseases while improving fruit storage performance.

Fruit susceptibility outweighs seasonal conditions

According to the study, the occurrence of stem-end and body rots is more closely associated with the fruit's inherent susceptibility at harvest than with environmental conditions during the growing season.

However, the researchers also note that no universal seasonal pattern exists because disease intensity ultimately depends on the interaction between avocado variety and the specific pathogen involved.

Source

Camiletti, B. X., Asensio, C. M., Carraro, T. A., Gusella, G., Focht, E. D., Pandey, R., Michailides, T. J., & Arpaia, M. L. (2026). Influence of fruit maturity and variety on seasonal postharvest fungal diseases and vascular streaking in California avocados. PLOS ONE. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0351752