Pulsed light reduces postharvest losses of Chinese bayberries by affecting fungal microbiota during cold storage

Abstract

Non-thermal sterilization technology is considered a safe and effective approach in controlling postharvest losses of fruit. In this study, the effects of pulsed light (PL) on qualities of Chinese bayberries during storage at 10 °C, 95% RH for 12 d were investigated. At the same time, high-throughput sequencing was operated to identify fungal microbiota on Chinese bayberries. The results showed that PL treatment could inhibit the decay incidence and polyphenol oxidase (PPO) activity, maintain fruit firmness and enhance phenylalanine ammonia-lyase (PAL) activity, with no effect on titratable acid (TA), total soluble solids (TSS), malondialdehyde (MDA) content and superoxide dismutase (SOD) activity. Additionally, the PL treatment maintained alpha diversity and altered beta diversity. At the species level, the abundance of Monographella nivalis and Colletotrichum cordylinicota were reduced in PL samples, while Hanseniaspora uvarum and Diaporthe spp were enriched. M. nivalis and C. cordylinicota were positively correlated with weight loss and decay index according to canonical correspondence analysis (CCA). The data of microbial correlation network indicated that PL treatment reduced pathogenic fungal microbiotas and made fungal community more complex and steadier. This study demonstrated that PL affects fungal community by inhibiting plant pathogens, increasing the amounts of endophytes and consolidating microbial networks. It provides new insights into the dynamics of the microbiome of Chinese bayberries after PL treatment.