During storage and transportation after harvest, the
jujube fruit is susceptible to black spot rot, which is caused by Alternaria alternata. The present study aimed to evaluate the effectiveness of the yeast Meyerozyma caribbica in controlling A. alternata in postharvest jujube fruits, and to explore the biofilm formation mechanism. The results showed that M. caribbica treatment significantly reduced the A. alternata decay in jujube fruits. M. caribbica could rapidly colonize
jujube fruit wounds, adhering tightly to hyphae of A. alternata, and accompanied by the production of extracellular secretions. In in vitro experiments, we identified that M. caribbica adhered to
polystyrene plates, indicating a strong biofilm-forming ability. Furthermore, we demonstrated that M. caribbica can secrete
phenylethanol, a quorum sensing molecule which can affect biofilm development.
Phenylalanine (a precursor substance for
phenylethanol synthesis) enhanced the secretion of
phenylethanol and promoted the formation of M. caribbica biofilms. Meanwhile,
phenylalanine enhanced the
biological control performance of M. caribbica against jujube black spot rot. Our study provided new insights that enhance the
biological control performance of antagonistic yeast.