Nanoparticle Treatments Show Promise Against Deadly Grapevine Trunk Diseases

An international research team has reported promising results in the fight against grapevine trunk diseases, a group of fungal infections that threaten vineyards worldwide. The study, published in August in Pest Management Science, involved scientists from several European institutions, including the BIOTIVIS group at the Institute of Grapevine and Wine Sciences (ICVV) in Spain. Over two growing seasons, the researchers tested silver-selenium nanoparticles (AgSe NPs) and four chemical compounds on grapevines infected with three major pathogens: Diaporthe eres, Diplodia seriata, and Eutypa lata.

The experiments took place in a net house at Mendel University in Brno, Czech Republic, using Sauvignon Blanc vines known for their susceptibility to trunk diseases. The team selected AgSe NPs and four chemicals—sodium arsenite, 8-hydroxyquinoline, silver nitrate, and a silver thiosulfate complex—based on previous laboratory tests showing strong antifungal activity. Each treatment was applied directly to wounds on the grapevine stems, which were then inoculated with one of the target fungi. The researchers monitored plant growth, internal wood necrosis, and the ability to re-isolate the pathogens from treated plants. They also analyzed changes in the expression of grapevine defense genes.

Results showed that all treatments reduced disease progression compared to untreated controls. Silver-selenium nanoparticles were particularly effective against D. eres and E. lata, achieving inhibition rates between 55% and 87%. The nanoparticles did not cause any visible phytotoxic effects at the concentrations used. Among the chemical treatments, 8-hydroxyquinoline and silver nitrate also demonstrated high levels of inhibition against some pathogens. Sodium arsenite, a compound previously banned in many countries due to toxicity concerns, showed strong antifungal effects but is unlikely to return to widespread use.

The study found that treated vines generally had less internal necrosis and better root development than untreated controls. In some cases, treated plants grew taller or developed longer roots than those exposed only to water and fungal infection. Pathogen re-isolation confirmed that infections were successfully established in most cases, allowing for reliable assessment of treatment efficacy.

Gene expression analysis revealed that different treatments triggered distinct responses in grapevine defense pathways. For example, some compounds downregulated NPR1, a gene involved in systemic acquired resistance, while others affected genes related to chitinase production or stilbene synthesis—both important for plant defense against fungi. The response varied depending on both the treatment and the pathogen involved.

Grapevine trunk diseases are a major concern for wine producers around the world. These diseases are caused by a complex of fungi that invade woody tissues, leading to cankers, dieback, and eventual vine death. Control options are limited because curative treatments are largely ineffective once infection is established. Many traditional fungicides are restricted or banned due to environmental and health concerns.

The use of nanoparticles represents a new approach to plant protection. Nanomaterials like AgSe NPs have unique properties that allow them to interact with pathogens at very small scales while potentially reducing overall chemical use in agriculture. In this study, AgSe NPs provided strong antifungal activity without harming the grapevines at tested doses.

The research team notes that while these results are encouraging, further studies are needed before nanoparticle-based treatments can be widely adopted in commercial vineyards. Field trials under real-world conditions will be necessary to confirm efficacy and safety over multiple seasons and across different grape varieties. Regulatory approval processes will also need to address questions about environmental impact and human health.

This work highlights ongoing efforts by scientists to find sustainable alternatives to conventional pesticides in viticulture. As restrictions on chemical use tighten across Europe and other wine-producing regions, growers are seeking new tools to protect their crops from devastating trunk diseases. Nanotechnology may offer one such tool if future research continues to support its effectiveness and safety.

The study was led by researchers from Mendel University in Brno with contributions from Spanish scientist David Gramaje at ICVV. It adds to a growing body of evidence suggesting that targeted nanomaterials could play a role in integrated disease management strategies for vineyards facing persistent fungal threats.