Diversity of Botryosphaeriaceae Species Associated With Grapevine Dieback in France: Life Traits and Aggressiveness

Members of the Botryosphaeriaceae are ubiquitous and are involved in the decline of many woody plants, including grapevine. They pose a particular threat to the quality and quantity of grape harvests and affect the longevity of vineyards worldwide. Understanding the diversity, distribution and life traits of these pathogens is crucial for improving disease management. In this study, we analysed Botryosphaeriaceae isolates from symptomatic or asymptomatic vines in six wine‐growing regions of France. Seven species of Botryosphaeriaceae were found, belonging to the genera Botryosphaeria, Diplodia, Lasiodiplodia, Neofusicoccum and Dothiorella . The most prevalent species were Diplodia seriata and Neofusicoccum parvum . Selected French isolates and reference isolates (from the Fungal Biodiversity Centre) were characterised molecularly with different primers (LSU/28S, ITS, EF1, Tub2); also, their ability to grow at different temperatures (15°C, 28°C and 33°C) and to cause cankers and necrosis in Vitis vinifera were evaluated. Neofusicoccum and Lasiodiplodia isolates exhibited greater aggressiveness than Diplodia , Botryosphaeria and Dothiorella . Building on previous published virome characterisations, we attempted to evaluate the potential impact of mycoviruses on the measured life traits. The findings suggest that some of the mycoviruses identified might affect certain life traits (e.g., the ability to grow at 33°C and canker size), depending on the virus–fungal species combination. This study provides a molecular and biological characterisation baseline for Botryosphaeriaceae species circulating in French vineyards, together with a first attempt to evaluate the impact of their associated virome, laying the groundwork for a better understanding of the interactions between Botryosphaeriaceae and grapevine.