Characterization of Fungal Communities Associated with the Lenticel-Like Damage of ‘Hass’ Avocados in Two Geographical Locations in Colombia

Abstract

Different postharvest diseases and disorders affect ‘Hass’ avocado fruits. Among them, lenticel-like damages, which compromise the fruit epidermis without affecting the mesocarp, are important causes of fruit rejection worldwide. However, lenticel-like damage etiology is still unclear. To better comprehend this disorder, we evaluated the level of the lenticel-like damage from Hass avocado fruits from two different growing regions in Colombia at different harvest seasons. We also characterized the fungal microbial communities associated with these fruits by Illumina MiSeq. We found that the level of lenticel-like damage varies with the farm and with the harvest season, and increases during cold storage. Fungal communities associated with Hass avocado fruits were influenced by the farm and the lenticel-like damage level. Regardless of the farm, Ascomycetes were increased four-fold compared with Basidiomycetes in severely damaged fruits, while in mildly damaged fruits the ratio was equal. In particular, severely damaged fruits from the more affected farm (El Sinaí) were enriched in Colletotrichum and Pseudocercospora, while fungi in mildly damaged fruits from the less affected farm (La Escondida) include Cladosporium, Vishniacozyma, Meira, and Symmetrospora. Altogether, our results suggests that fungal communities of Hass avocado exocarps influence the lenticel-like damage development and might be responsible for the damage differences between farms.

Keywords

• Colletotrichum
• lenticelosis
• next-generation sequencing
• Persea americana
• Pseudocercospora