Yeasts from the Peruvian native cacao (Theobroma cacao L.) phyllosphere and their biocontrol potential against Moniliophthora roreri

Abstract Moniliophthora roreri is the causal agent of frosty pod rot, one of the most yield-reducing diseases of cacao ( Theobroma cacao L.) in Latin America. However, there is currently no effective control method for this disease. The objective of this research was to isolate and identify the natural diversity of yeasts present in the phyllosphere of native cacao and to evaluate these isolates for potential antagonistic interactions against M. roreri . Fruits and leaves from Peruvian native cacao were collected and epiphytic yeasts were isolated and purified. Single-colony isolates were characterized by macro and micromorphological characteristics, and molecularly based on sequences of the D1/D2 and ITS1-5.8S-ITS2 regions of the rRNA gene. A total of thirty species distributed in sixteen genera were found. Moreover, the yeasts Wickerhamomyces anomalus KLG-014 and Candida sorboxylosa KLG-104 showed high biocontrol potential against M. roreri as revealed by antibiosis in vitro assays. These results demonstrate, for the first time, the high diversity of yeasts present in the phyllosphere of native Peruvian cacao, and the discovery of species with potential for biocontrol of M. roreri .