SEAWINES: Use of macroalgae as biostimulants against fungal diseases in grapevines

¹ Department of Genetics, Physical anthropology and Animal physiology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Leioa (Bizkaia), Spain
² IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
³ IFAPA Rancho de la Merced, Consejería de Agricultura, Pesca, Agua y Desarrollo Rural, Junta de Andalucía, 11471 Jerez de la Frontera, Spain
⁴ Neiker, Plant Protection and Production department, Campus Agroalimentario de Arkaute, 01080 Vitoria-Gasteiz, Spain
⁵ Department of Plant Biology and Ecology, Faculty of Pharmacy, University of the Basque Country (UPV/EHU), Vitoria-Gasteiz (Araba), Spain
⁶ VIENAP Group, ICVV, Carretera de Burgos, Km. 6, 26007 Logroño, Spain
⁷ Univ. Bordeaux, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, 33140 Villenave d´Ornon, France
⁸ Bordeaux Sciences Agro, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, 33170 Gradignan, France
⁹ The Council for Agricultural Research and Economics (CREA), Research Centre for Viticulture and Enology, 31015 Conegliano, Italy
¹⁰ Department of Plant Biology and Ecology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Leioa (Bizkaia), Spain
¹¹ IFAPA El Toruño, Consejería de Agricultura, Pesca, Agua y Desarrollo Rural, Junta de Andalucía, 11500 Puerto de Santa Maria, Spain

Abstract

The outlook for climate change foresees major impacts on vineyards worldwide, shifting pathogens distribution and dynamics demanding more intense plant protection measures in certain regions, increasing viticulture's dependence on phytochemicals and pesticides. However, the European Commission is applying restrictions on their use, encouraging the development of more sustainable strategies efficient for disease control. Seaweeds represent an ecological alternative for a more sustainable production. Previous studies have shown that algae extracts contain compounds capable of reducing the abundance of plant fungal pathogens. Despite it, little is known about the molecular mechanism underlying this response.

SEAWINES project is evaluating the efficacy of the foliar application of Ulva ohnoi and Rugulopteryx okamurae extracts to control powdery and downy mildew, in addition to testing their effect on grape and wine quality. To our knowledge, this is the first study evaluating R. okamurae biostimulant capacity and fungicidal effect in viticulture. This macroalgae is relevant since it is an invasive species in our coasts, causing incalculable economic and environmental burdens. We aim to 1- Reduce the usage of chemicals in grapevines; 2- Reduce fungal diseases in viticulture; 3- Valorize polysaccharides from seaweeds; 4- Increase the added-value to wines (ecological and quality); and 5- Provide an alternative use to seaweed biomass, contributing to bio-circular economy and reducing its accumulation in our coasts.