Clonostachys chloroleuca: A novel pathogen causing cassava root rot disease in Misiones Province, Argentina

Abstract

Cassava (Manihot esculenta) is a crucial food source facing a threat from Cassava Root Rot Disease (CRRD), often caused by fungi like Fusarium, Lasiodiplodia, Phytophthora, among others. In this study, roots from cassava plants displaying CRRD symptoms were collected in Argentina. The isolated fungus, identified as Clonostachys chloroleuca through morphological and molecular methods, was confirmed as the cause of CRRD. In vitro severity tests revealed a high severity value of 22%. The fungus exhibited vigorous growth on root surfaces, causing deep dark coloration and dry pulp consistency. In vivo assays on cassava plants supported the manifestation of typical CRRD symptoms. This study marks the first report of C. chloroleuca causing CRRD, emphasizing its potential threat to cassava production. Further research is essential to understand its pathogenic mechanisms and validate findings in real-world conditions.