Research projects

Maize is one of the most important crops in Slovenia, making crop health essential for the stability of agricultural production. One of the potential threats is Stewart’s wilt of maize, caused by the bacterium Pantoea stewartii subsp. stewartii, which can cause significant yield losses.

The bacterium originates from the Americas, where it is efficiently transmitted by the corn flea beetle (Chaetocnema pulicaria), a small beetle that feeds on maize leaves and spreads the infection to healthy plants. Although the corn flea beetle is not present in Europe, the bacterium is a regulated harmful organism in the EU, as its establishment could have serious consequences. Over long distances, the bacterium is primarily spread through infected seed, while insect vectors play an important role in its spread within fields. Maize is the main host, with sweet corn being particularly susceptible, although sorghum, grasses and weeds can also become infected.

Since 2017, Slovenia has implemented monitoring and diagnostic programmes coordinated by the Administration of the Republic of Slovenia for Food Safety, Veterinary Sector and Plant Protection (UVHVVR), in cooperation with inspectors of the Plant Protection Service and the laboratory of the National Institute of Biology (NIB). Since 2018, infections with Pantoea stewartii subsp. stewartii have also been confirmed in Slovenia, mostly in the Vipava Valley and primarily in maize intended for silage. The main risk is the establishment of the bacterium in Slovenia and its spread to the major maize-growing areas in north-eastern Slovenia.

At present, Slovenia is protected from the rapid spread of the disease mainly by the absence of an efficient vector capable of overwintering the bacterium. However, the risk could increase if the corn flea beetle were introduced from the Americas or if native insect species became capable of transmitting the bacterium.

The research project MapQuest – Advanced Strategies for Managing Quarantine Bacterial Wilt of Maize in Slovenia therefore focuses on developing knowledge and strategies for the effective management of risks associated with bacterial wilt of maize and preventing its spread and establishment in Slovenia.

Partnership

• National Institute of Biology
• Institute of agriculture and forestry Maribor
• Agricultural Institute of Slovenia
• Institute of agriculture and forestry Nova Gorica