Fungal communities associated with postharvest strawberries in Western Australia

Abstract

Spoilage of postharvest strawberries by fungal pathogens is a major global concern. This study employed culture-dependent and culture-independent methods to identify postharvest fungal communities of strawberries in Western Australia (WA). Ripe strawberries from eight varieties were sampled twice, early and late in the growing season, from 20 farms in two growing regions. At the first sampling time, traditional isolation and identification demonstrated a high abundance of Botrytis and Cladosporium in Region 1. Mucor was abundant at the second sampling time in Region 1 and both times in Region 2. Metabarcoding confirmed variety-specific fungal communities in WA strawberries. Botrytis and Cladosporium were predominant in Region 1 and Region 2 samples with more than 50% read abundance except on variety Suncoast. No Mucor sequences were detected using metabarcoding, although they were isolated from all samples using culture-based methods. Sisquoc, a hydroponic variety, had a significantly higher fungal diversity than the soil-grown varieties. Varieties Suncoast and Albion exhibited the lowest fungal diversity compared to others. This study demonstrated the value of using culture-dependent and culture-independent methods to investigate the complexity of fungal microbiomes of postharvest strawberries.