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

Abstract

Fungal endophytes occurring in grapevine (Vitis vinifera 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 Fusarium, Alternaria, or Aspergillus, 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 Alternaria sp. cultures, but traces of these mycotoxins were also quantified in the Diatripe and Epicoccum cultures. Meleagrin and roquefortine C were detected in Didymella sancta and Penicillium crustosum, gliotoxin was detected in Alternaria sp., Didymella sp., Aureobasidium pullulans, Cladosporium herbarum, Penicillium crustosum and Pleurophoma ossicola, 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 V. vinifera growing.

A Novel Seimatosporium and Other Sporocadaceae Species Associated with Grapevine Trunk Diseases in Cyprus

“…Seimatosporium and Sporocadus consist predominately of endophytes and saprobes of woody plants [ 17 , 33 , 34 , 43 ], although some species are pathogens of different plant hosts, such as eucalypt, blackberry, and grapevine [ 13 , 54 , 55 ]. More specifically, out of the nine Seimatosporium species previously reported from diseased or dead grapevine wood worldwide, only five ( Seim.…”

“…In the present study, Seimatosporium and Sporocadus isolates were retrieved from wood cankers either solely or in combination with other known trunk pathogens, such as Ph. chlamydospora, P. minimum , and B. dothidea , while they have also been recovered from asymptomatic vine tissues [ 11 , 12 , 43 , 65 ]. Recent studies, that investigated the effect of dual inoculations between Sporocadaceae from grapevines and known GTD pathogens, report synergistic, as well as antagonistic interactions, confirming their involvement in the GTD complex [ 38 , 65 ].…”

“…rosigena F. Liu, L. Cai and Crous [ 26 , 27 , 34 ], that have also been associated with V. vinifera . However, limited information is available regarding their pathogenic potential, mainly reported as endophytic saprobes of grapevine and other hosts [ 11 , 12 , 18 , 41 , 42 , 43 ].…”

Introduction to This Special Issue of Toxins: Reduction and Control of Mycotoxins along Entire Food and Feed Chain

“…The safety of biological agents is discussed in the paper by Stranska et al [ 4 ]. Fungal endophytes, on the one hand, promote the growth of the plant and produce bioactive substances needed for better ripening, while on the other, they represent a source of mycotoxins.…”

“…The toxicogenic potential of fungal endophytes isolated from vineyards was assessed, and most of the isolates were able to produce mycotoxins. Therefore, the effect of the endophyte used for growing Vitis vinifera on mycotoxin production should always be properly investigated [ 4 ].…”