Survival of Trichoderma atroviride SC1 on grapevine pruning woundsand efficacy against Esca disease agents

Abstract: Esca disease is causing damage in vineyards in several parts of the world. The diseaseis caused by three different fungi (Phaeomoniella chlamydospora, Phaeoacremonium aleophilumand Fomitiporia mediterranea), On the whole these pathogen affects the shoot of the trunk andthe branches with chronic or acute evolution. At the moment the prevention of pruning woundsinfection by following correct cultural practices remains the main way to manage the disease butthe possibility of introducing microorganisms as biological control seems to represent analternative or a complementary strategy. We studied the survival of Trichoderma atroviride SC1on pruning wound vineyard (107 conidia/ml) applied during winter at two different stages (BBCH00 and 01), and its efficacy to reduce the colonization of Pal and Pch of grapevine pruningwounds in potted plants. T. atroviride SC1 can survive in the wood for several months, but thepercentage of colonised wounds decreases during time, probably because of the temperature risein the vineyard. For this reason, 45 different ingredients (wetting agents, UV protectors,nutritional factors, etc.) were tested in the formulation of a semi-commercial product based onT. atroviride SC1 with the aim to improve its germination and persistence on pruning wounds.T. atroviride SC1 can successfully control wound infections of Pch and, at lower extent, of Pal.