Diversity in Beauvericin and Enniatins H, I, and MK1688 by Fusarium oxysporum isolated from potato.

Beauvericins and enniatins are cyclohexadepsipeptide mycotoxins that exhibit phytotoxicity and insecticidal activities. In the present study, the production of beauvericin and newly found enniatins (H, I, and MK1688) was characterized in 28 Fusarium strains isolated from potato samples in Korea. The predominant Fusarium species in potato was F. oxysporum (53.6%). Fifteen strains of F. oxysporum and two strains of other Fusarium species produced beauvericin (at concentrations from 3.1 to 743.2 microg/g) in culture on rice. Enniatins H and I were produced by 3 and 11 strains at concentrations from 33.1 to 781.3 microg/g and from 6.5 to 730.3 microg/g, respectively. Five isolates produced enniatin MK1688 at concentrations from 4.6 to 432.6 microg/g. In particular, one isolate (No. 1501) identified as F. oxysporum and two other Fusarium strains (Nos. 804 and 910) produced all of the tested toxins. These results indicate that enniatins H, I, and MK1688 and beauvericin are produced by Fusarium isolates occurring on potato. We do not know if the toxins can accumulate in the environment since it was not demonstrated.