AUTHOR=Silva-Valderrama Isidora , Toapanta Diana , Miccono Maria de los Angeles , Lolas Mauricio , Díaz Gonzalo A. , Cantu Dario , Castro Alvaro 

TITLE=Biocontrol Potential of Grapevine Endophytic and Rhizospheric Fungi Against Trunk Pathogens

JOURNAL=Frontiers in Microbiology

VOLUME=11

YEAR=2021

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2020.614620

DOI=10.3389/fmicb.2020.614620

ISSN=1664-302X

ABSTRACT=<p>Grapevine Trunk Diseases (GTDs) are a major challenge to the grape industry worldwide. GTDs are responsible for considerable loss of quality, production, and vineyard longevity. Seventy-five percent of Chilean vineyards are estimated to be affected by GTDs. GTDs are complex diseases caused by several fungi species, including members of the Botryosphaeriaceae family and <italic>Phaeomoniella chlamydospora</italic>, considered some of the most important causal agents for these diseases in Chile. In this study, we isolated 169 endophytic and 209 rhizospheric fungi from grapevines grown under organic and conventional farming in Chile. Multiple isolates of <italic>Chaetomium</italic> sp., <italic>Cladosporium</italic> sp., <italic>Clonostachys rosea, Epicoccum nigrum, Purpureocillium lilacinum</italic>, and <italic>Trichoderma</italic> sp. were evaluated for their potential of biocontrol activity against <italic>Diplodia seriata</italic>, <italic>Neofusicoccum parvum</italic>, and <italic>Pa. chlamydospora.</italic> Tests of antagonism were carried out using two dual-culture-plate methods with multiple media types, including agar containing grapevine wood extract to simulate <italic>in planta</italic> nutrient conditions. Significant pathogen growth inhibition was observed by all isolates tested. <italic>Clonostachys rosea</italic> showed 98.2% inhibition of all pathogens in the presence of grapevine wood extract. We observed 100% pathogen growth inhibition when autoclaved lignified grapevine shoots were pre-inoculated with either <italic>C. rosea</italic> strains or <italic>Trichoderma</italic> sp. Overall, these results show that <italic>C. rosea</italic> strains isolated from grapevines are promising biocontrol agents against GTDs.</p>