Application of stressed and microencapsulated Meyerozyma caribbica for the control of Colletotrichum gloeosporioides in avocado (Persea americana Mill. cv. Hass)

The antagonistic capacity of Meyerozyma caribbica subjected to hydric and thermal stress and microencapsulated by spray drying against Colletotrichum gloeosporioides was evaluated. M. caribbica grown in medium modified with 1.5 M NaCl and 38 °C increased its viability to 126.36 and 108.78% at a water activity (aw) = 0.98 and 0.96, respectively, compared to the control (100%, aw = 1.0) after 48 h of incubation. Under the same conditions, yeast enhanced its antagonistic activity from 49.27 up to 75.11%. Then, the biocontrol efficacy of different treatments with fresh, stressed, or microencapsulated yeast was evaluated on the incidence and severity of anthracnose disease in avocado fruits. All treatments showed 100% incidence at 10 d of storage at 27 °C; however, all treatments reduced the severity of the disease compared with the control treatment. The best results were obtained with the microencapsulated stressed yeast, which reduced the lesion diameter by 45.43% compared with the control. This study demonstrated the capacity of M. caribbica subject to hydric and thermal stress to increase its viability, improve biocontrol efficacy, and show potential for future preharvest stage applications in avocado fruits.