SOS HERBICIDE RESISTANCES IN VINEYARDS

The repeated use of an increasingly narrow range of herbicides, as a consequence of the withdrawal of many herbicides from the EU market due to strict regulations (Reg EC/1107/2009), and the lack of herbicides with new modes of action (MoA) have led to the evolution of resistance, representing an upcoming problem for weed management. In the vineyard, too, recent years have seen the evolution of weed populations resistant to the most commonly used herbicides, such as glyphosate. In the framework of the NODES project, funded by the MUR – M4C2 1.5 of PNRR funded by the European Union - NextGenerationEU (Grant agreement no. ECS00000036), the assessment of different herbicide resistance types (target site resistance – TSR, non-target site resistance – NTSR and resistances regulated by epigenetic mechanisms) in vineyards in the Oltrepo Pavese wine-growing area (Lombardy, Italy) is performed using genetic and omics-based approaches, also considering the main ecological factors influencing epigenetic mechanisms. Through a preliminary flora-vegetation survey (Braun-Blanquet approach), some problematic weeds such as Echinochloa crus-galli (L.) P. Beauv., Conyza canadensis (L.) Cronq., Sorghum halepense (L.) Pers. and Cynodon dactylon (L.) Pers. have been identified. For the next studies, seeds collected from plants survived herbicide application will be grown under controlled conditions and herbicide administration trials will be performed in order to discriminate resistant and sensitive biotypes. Herbicide resistances will be classified through specific molecular analyses investigating the presence of DNA missense mutations and/or epigenetic mechanisms regulating the expression of genes involved in herbicide detoxification. With the aim of optimizing precision weed management (PWM), a better understanding of the nature of resistance can help, taking into account genetic-environmental interactions, to plan more targeted and sustainable management strategies, reducing inputs and improving environmental and food health.