Fungal Endophytes of Vitis vinifera- Plant Growth Promoters or Potentially Toxinogenic Agents?

Fungal endophytes occurring in grapevine ( L.) are usually important sources of various compounds with biological activities with great potential for use in agriculture. Nevertheless, many species isolated from this plant belong to the genera , , or all of which are well-known to produce mycotoxins. Our study is focused on the assessment of the toxinogenic potential of fungal endophytes isolated from vineyards in the Czech Republic. In total, 20 endophytic fungal species were cultivated in wine must, and 57 mycotoxins of different classes were analysed by liquid chromatography coupled with mass spectrometry. As a result, alternariol, tentoxin, meleagrin, roquefortine C, gliotoxin, and verruculogen were detected in the culture medium, of which verruculogen followed by gliotoxin were the most frequent (present in 90 and 40% of samples, respectively) and most concentrated (up to thousands ng/mL). The alternaria mycotoxins alternariol and tentoxin were detected not only in sp. cultures, but traces of these mycotoxins were also quantified in the and cultures. Meleagrin and roquefortine C were detected in and gliotoxin was detected in sp., sp., , , and , and verruculogen was quantified in 99% of endophytic isolates investigated. The potential of endophytes to produce mycotoxins should be carefully checked, specifically in cases where they are intended for the purpose of growing.