Identification, mycotoxin risk and pathogenicity of Fusarium species associated to fig endosepsis in Apulia.

Antonio Moretti (1) , Lia Ferracane (2) , Stefania Somma (3) , Vincenzo Ricci (1) , Giuseppina Mule , Antonia Susca (1) , Alberto Ritieni (4, 5) , Antonio Logrieco (3)

1 ISPA - Istituto Scienze delle Produzioni Alimentari
2 Department of Sciences of Fodd
3 ISPA - Institute of Sciences of Food Production
4 Department of Food Science
5 Department of Food Science

In a survey carried out on 87 rotted fig fruits samples collected in Apulia region, we isolated 126 Fusarium strains identified as F. ramigenum (69 strains), F. solani (49 strains), F. proliferatum (5 strains) and 3 not identified strains. Investigation on the fertility of the strains belonging to F. proliferatum and F. ramigenum revealed that only strains of F. proliferatum were fertile. The identity of F. ramigenum strains was confirmed by sequencing a portion of the translation elongation factor gene. When Fusarium species were analyzed for their toxigenicity, F. ramigenum (69 strains) produced fusaric acid (FA), 37 strains up to 525 mg/kg; beauvericin (BEA), 30 strains up to 190 mg/kg; fumonisin B1 (FB1) and fumonisin B2 (FB2), 60 strains up to 1,575 mg/kg of total FBs; and fusaproliferin (FUP), 2 strains up to 345 mg/kg; F. proliferatum (5 strains) produced FA, all strains at low levels; BEA, 2 strains up to 205 mg/kg; FB1 and FB2, 1 strain 1,100 and 470 mg/kg, respectively; and FUP, 1 strain 820 mg/kg; F. solani (30 strains) produced FA, 13 strains up to 215 mg/kg. Few fungal extracts showed high toxicity toward brine shrimp larvae and in some cases in relation to BEA and FA content. A pathogenic assay on fig fruits showed that all three species were pathogenic, with higher virulence by F. ramigenum. These data report for the first time the production of BEA and FB1/FB2 by F. ramigenum and show that it is a main agent of fig endosepsis in Apulia and can contribute to the fumonisin contamination of fresh and dried figs.

Mots clés: Life Sciences

Antonio Moretti, Lia Ferracane, Stefania Somma, Vincenzo Ricci, Giuseppina Mule, et al.. Identification, mycotoxin risk and pathogenicity of Fusarium species associated to fig endosepsis in Apulia.. Food Additives and Contaminants, 2010, 27 (05), pp.718-728. ⟨10.1080/19440040903573040⟩. ⟨hal-00591177⟩