Potential Invasion risk of the rice stem borer, Chilo suppressalis, in Europe using CLIMEX.

Invasive pest species are the most serious threat to the resilience of agroecosystems. They cause direct damage by reducing crop yield and increasing management costs, and indirect damage through agroecosystem disturbances. To mitigate the risks posed by invasive pests, identifying their potential distribution is a crucial prerequisite. This study predicted the climatic suitability of the rice stem borer (RSB), Chilo suppressalis, within Europe using a species distribution model, CLIMEX. RSB first invaded Spain in the 1930s and has since caused significant damage, with reports of its presence in France, Hungary, and near the Caspian Sea in Russia. The overall suitability for RSB in Europe, while lower than its native region in East Asia, is predicted to be habitable across the European mainland. Notably, the climates of Mediterranean countries (e.g., Greece, Italy, France, Spain, Croatia, etc.) are expected to be sufficiently suitable for RSB habitation. Currently, RSB is also reported in Hungary, but the exact route of invasion is unclear; thus, it is necessary to investigate whether these are extensions of the existing populations in Spain and France or the result of accidental introduction through trade. Moreover, in southern Europe, where rice production is high, there is a risk of significant damage similar to that in Spain. Therefore, quarantine and prevention measures against RSB invasion are required.