Fusarium species and moniliformin occurrence in sorghum grains used as ingredient for animal feed in Argentina

PENA G.,; FUMERO V; CAVAGLIERI L.R.,; CHULZE S.,

Feising

Workshop; International Commission on Food Microbiology.; 2016

International Commission on Food Microbiology.

Sorghum (Sorghum bicolour L) is the fourth most important summer crop in Argentina after soybean, corn andsunflower. In our country, its importance lies in the use of grains and fodder as a supplement for animal feed.Argentina ranks second as sorghum exporter in the world. Fusarium species usually associate with sorghum belongto Fusarium fijikuroi species complex and can produce mycotoxins that are harmful to both humans and animals.The aims of this study were to determine Fusarium species and the moniliformin (MON) contamination in48 sorghum grain samples collected from two fields located in Córdoba, Argentina. The Fusarium species wereisolated on Nash Snyder medium. A total of 688 Fusarium strains were randomly taken and transferred to SNAagar. After single-spore culturing, 201 isolates were identified to species level by morphological characteristics oncarnation leaf agar (CLA) and potato dextrose agar (PDA). Translation elongation factor- 1 alpha (EF-1α) gene wasamplified in selected strains showing morphological characteristics of F. verticillioides. Moniliformin was detectedby UV HPLC coupled to SPE column clean up. All samples showed Fusarium contamination with infection levelsranging from 82.5 to 99%. Among the Fusarium fijikuroi species complex identified, F. verticillioides was the mostfrequently recovered (46.4%) followed by F. proliferatum (13.9%) and F. subglutinans (8.2%). Based on the EF-1αgene sequences the strains were F. thapsinum and F. andiyazi. Species within the Fusarium graminearum speciescomplex also were isolated in a high frequency (26.3%). Other Fusarium species identified were: F. semitectum,F. oxysporum and F. sporotrichioides. Natural occurrence of MON was observed. The toxin levels detected rangedfrom 363.2 to 914.2 ng/g (mean value: 605.06 ng/g).