Survey and toxigenic abilities of , , and fungi from wheat and paddy grains in Shanghai, China.

A systematic study was carried out on 638 wheat and paddy grains (including fresh and stored samples) collected in 2021 from Shanghai, China, to identify the major mycobiota and their toxigenic abilities. A total of 349 fungi, namely, 252 , 53 , and 44 , were characterized by morphological and molecular identification. and were more frequently isolated in paddy with species complex and section as the predominant species, respectively. The genus was the most frequently isolated fungal species in wheat. The toxin-producing potentials of the identified fungi were further evaluated . Deoxynevalenol (DON) was produced by 34.5% of isolates and zearalenone (ZEN) was produced by 47.6% of them, and one isolate also processed the abilities for fumonisin B (FB), B (FB), and B (FB) productions. Aflatoxin B (AFB), B (AFB), and G (AFG) were only generated by section , with the production rate of 65.5%, 27.6%, and 13.8%, respectively. Alternariol (AOH) was the most prevalent toxin, which could be produced by 95.5% of the isolates, followed by alternariol monomethyl ether (AME) (72.7%), altenuene (ALT) (52.3%), tenuazonic acid (TeA) (45.5%), tentoxin (TEN) (29.5%), and altenusin (ALS) (4.5%). A combinational analysis of mycobiota and toxigenic ability allowed us to provide comprehensive information about the production mechanisms of mycotoxins in wheat and paddy in a specific geographic area, and will be helpful for developing efficient prevention and control programs.