Oral Presentation Australasian Plant Pathology Society Conference 2025

Challenges in European and Italian viticulture for management of grapevine diseases (123712)

Laura Mugnai 1
  1. University of Florence, FIRENZE, Italy

Grapevine is a long-established and important fruit crop in Europe, which requires large scale pesticide use for vine protection. This region has recently reviewed regulations for pesticide use reduction, and for developing safe alternatives. Following directive 2009/128/EC, individual countries have established National Action Plans for Sustainable Use of Plant Protection Products. If the optimistic aim to reduce pesticide use by 50% is far to be achieved, pressure remains for crop production systems to develop and apply prevention and effective disease control with a lower environmental and human health impact. This requires increasing use ofcultural practices that reduce grapevine susceptibility to pathogens, common use of predictive models, and increased targeting in product application. The use of alternatives to chemical disease management, including biocontrol, strengtheners, basic substances, and defence inducers, particularly for the classic threats from downy and powdery mildews is encouraged. Climate change is also making fungicide-only strategies difficult, and increases requirement to apply multi-method disease control. Another big issue in Italy and Europe remains trunk diseases – considered by growers the one most damaging and difficult to manage. Spread of esca disease, and of the dieback agents Botryosphaeriaceae spp., Eutypa, and Diaporthe, leads to important losses in grape yields, and, from esca, product quality. Increasing European attention is being given to the role of pruning management from year 1 of vine growth as it influences host responses to colonisation by aggressive wood pathogens. Wound protection with Trichoderma species and strains is slowly becoming popular and endotherapy is studied and applied in different ways in order to reduce esca impact on production. Foliar applications with defence inducers are also used to reduce esca incidence and the role of soil and nutrients is investigated. But this is not yet enough: two invasive vector-borne pathogens are also becoming important on grapevine. Flavescence dorée has recently spread in Southern Europe, including Italy, up to Tuscany, causing devastating damages. Pierce disease by Xylella fastidiosa subsp. fastidiosa also threatens, as it has been recently found in Apulia (the same areas where another Xylella subspecies has caused severe damage to olive trees). On both diseases, control is based on reducing infection through inoculum management, with monitoring and mandatory removal of infected plants, vector control, and strict vineyard rules. New research approaches for management of all these grapevine diseases include development of precision techniques for disease monitoring and management that reduce pesticide applications while improving disease control.