The management of grapevine downy mildew: from anti-resistance strategies to innovative approaches for fungicide resistance monitoring

• DOI: 10.1007/s41348-024-00867-4
• Publication Date: 2024-02-10T12:02:13Z
• Authors: Silvia Laura Toff...; Beatrice Lecchi; Giuliana Maddalena; Demetrio Marcianò; Milda Stuknytė; Stefania Arioli; Diego Mora; Piero Attilio Bianco; Paolo Borsa; Mauro Coatti; Maya Waldner-Zulauf; Lorenzo Borghi; Stefano FF Torriani
• Keywords: Plasmopara viticola; Disease management; Venturia inaequalis; Systemic Acquired Resistance; Vineyard

Abstract Efficient grapevine downy mildew control necessitates the implementation of anti-resistance strategies to ensure ongoing efficacy available substances and optimal disease control. With gradual disappearance multi-site fungicides from market, reliance on single-site poses a long-term risk selecting strains resistant multiple modes action. Challenges in management encompass spray programs monitoring field population sensitivity. This study evaluated strategies, including two (mandipropamid oxathiapiprolin), fungicide sensitivity through combination trials laboratory tests for biological molecular characterization pathogen populations over three-year period (2019–2021). Mandipropamid, cellulose synthase inhibitor, is used since long time control, while oxathiapiprolin, an OxySterol Binding Protein homologue Inhibitor, was introduced recently. Field demonstrated effective even presence mandipropamid-resistant (with G1105S/V mutations PvCesA3 ) revealed pronounced selection spread resistance both vineyard where pressure higher. Characterizing remained significant obstacle monitoring, hindering precise determination frequencies related programs. Traditional techniques, fact, lack resolution required high-throughput isolation individuals. To address this challenge, we propose utilizing flow cytometry fluorescence-activated cell sorting sporangia populations, method able determine number isolates isolate single assay.