FILAMENTOUS FUNGI ASSOCIATED TO CASSAVA ROOT ROT DISEASE (CRRD) IN MISIONES PROVINCE (ARGENTINA)

MADRASSI, LUCAS M.; ALVARENGA, ADRIANA E.; MÓNACO, CECILIA ; ZAPATA, PEDRO D.

Congreso; Reunión Conjunta SAIB-SAMIGE 2020; 2020

Sociedad Argentina de Microbiología General

In Argentina, cassava´s main production is located in NEA provinces, especially in Misiones. Mayor yield lost are often related to root phytosanitary problems; they become rot, whether dry or soft, and lose their commercial value. These symptoms are known cassava root rot disease (CRRD) and their causal agent have not being recognize in Argentina. Causal agent´s recognition is a primary step toward disease control, because, otherwise, no specific products can be applied to counter them. In this work, we aimed to isolate filamentous fungi from cassava root rot samples taken from two crops whose presented characteristic CRRD symptoms. Root´s visible soil particles were removed using tap water. Roots were surface sterilized by submerging them in 70% alcohol solution for 5 minutes and then in 10% NaClO solution for 5 minutes. Periderm, cortex, pith, xylem bundles were carefully separated using sterilized bistoury. Pieces´ surface particles were removed centrifugation. Samples were cultivated in Petri dishes containing 20ml of potato dextrose, malt extract or malaquite green agar with antibiotics, for one week at 28ºC ±2 in darkness. Several fungal genera were found, mainly Fusarium spp., Geotrichum spp., Rhizopus spp., etc.These results indicate the preponderance of common soil filamentous fungi that might cause CRRD in Misiones. Further analysis might include strains´ molecular identification and virulence capability determination in order to determine whether these fungi are pathogenic or not.