First report of Berkeleyomyces basicola (synonymous: Thielaviopsis basicola) on roots of sweet potato (Ipomoea batatas (L.) Lam) in Argentina

PACCIORETTI M; MARTINO J.; CONTARDI C.; DI FEO L.; PASTOR S. E.

REVISTA DE LA FACULTAD DE CIENCIAS AGRARIAS DE LA UNIVERSIDAD NACIONAL DE CUYO

UNIV NACIONAL CUYO

Lugar: Mendoza; Año: 2021 vol. 53 p. 283 - 287

0370-4661

Symptomatic sweet potato cv Arapey INIA samples were collected from a commercialproduction field in Colonia Molina, Guaymallén department, Mendoza province, Argentina.They showed dark rounded lesions, sometimes coalescing with white granular mycelium.Fungus was obtained from symptomatic sweet potatoes, which represented the generalizedinfection that affected the crop. They were seeded in PDA with streptomycin sulfate andincubated for seven days at 21°C, alternating white/black (UV400nm) light. Observationswith an optical microscope revealed the presence of hyaline, not septated, cylindricalendoconidia with rounded ends. They were 8-16 μm length and 4?6 μm width. Phialideswere 43-46 μm length, rounded bases (7-9 μm width) and tapering to the neck´s tip (4-6 μmwidth). Brown chlamydospores (aleuriospores), 9-13 μm length and 8-12 μm width, inchains of 2-8 spores were observed. For molecular identification, total genomic DNA wasextracted. ITS fragment of 565 pb was amplified using ITS5/ITS4 primers and sequenced.The sequence indicated 99% identity with Berkeleyomyces basicola (synonymous:Thielaviopsis basicola). This was deposited in GenBank as (KX580957) (CBS: C430.74, GenBank accession number AF275482.1). This is the first report of B. basicola in sweet potatoin Argentina, a potential threat to storage root yields