Interaction between cold storage period and variety with occurrence of postharvest fungal infections in California avocados

This study investigates the interaction between cold storage duration and avocado variety with the occurrence of postharvest fungal rot expression in California avocados. This investigation focused on five commercial and five experimental avocado varieties. Avocado fruits were harvested and subjected to cold storage at 5°C for 1, 3, or 6 weeks. The study evaluated the severity of three disease symptoms: stem-end rot, body rot, and vascular streaking, as well as the frequency of causal pathogens such as species of Botryosphaeriaceae, Colletotrichum, and Diaporthe. Results indicated that prolonged storage significantly increased the severity of postharvest fungal disorders, with notable differences among varieties. 'Hass' served as the reference variety, exhibiting high disease severities with extended storage. Longer storage periods resulted in notable differences among varieties, with the severity of symptoms varying significantly. Some varieties performed better than 'Hass', while others performed worse, depending on the specific disease symptom. This variability made it challenging to identify varieties that consistently outperformed 'Hass' across all disease symptom types. The study also found that the frequency of pathogens varied with storage duration, with Diaporthe spp. becoming more prevalent during extended storage. These findings underscore the importance of considering both storage duration and avocado variety in postharvest management strategies to mitigate fungal diseases. The study suggests that new avocado varieties may require tailored storage conditions to maintain quality and reduce postharvest losses. These insights contribute to the development of more effective postharvest handling practices, ensuring the long-term sustainability of the avocado industry.